From patchwork Wed Nov 15 16:30:05 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ryan Roberts X-Patchwork-Id: 165472 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b909:0:b0:403:3b70:6f57 with SMTP id t9csp2657326vqg; Wed, 15 Nov 2023 08:33:12 -0800 (PST) X-Google-Smtp-Source: AGHT+IFK5ofX+A/Lcx1MjEeIg0GU17yjWmWsmWE5VmEcB90POVlBiFS9lXKPLyR4TJnDwrzVwDSk X-Received: by 2002:a17:903:2ce:b0:1ca:a07b:36d with SMTP id s14-20020a17090302ce00b001caa07b036dmr7685667plk.48.1700065991862; Wed, 15 Nov 2023 08:33:11 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1700065991; cv=none; d=google.com; s=arc-20160816; b=XFmqY3mCsCWTjDL1JSCfqpuof/G6hYygMul7d9JkoHmDvYfLnQGmGUWbmqkRMU9gD6 Fo/GFlaUWVFm2lS4KpDwc3SV6gZV/X1sM5j4vTNmSi2WzyrD20cxJ6POq21iVp358is2 phDsZOdOmqBstZJ7J4KhObJiPdF+/eAv0oR6eosSH/Da64aY8WS1pAfJBORzhPKwFtOo VXEdgAFHsS0VSB7T8H+ycMO5by0kZKeMH4OSybOqI3RwsTLIerwW3E/9GEIHb0CThsBd 6MLya8dswfRIAB/pBFVj9CY9JMsw1e3wARy0JKwqMitRRKbWGjmo/1u8mFkVfL/huBFc g50g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from; bh=UA2ixjHApskUia+IBoCjlNEhJLPlTkaoxaoP9EiJlwk=; fh=CVYMMnwSLqNeTtsgqDZkAN2xp/CPaSWpO0DiPqQVZ5w=; b=XBoJMDNmhxkfBtbF/wMLaOQJc6vYad/eYf/3yEs74cQRImy2MpFmVg4a87WmdwMr+Y T/NtjP2hDICNSaH9b9ycCH0FKFj3qXN99PK05tJul/+wwBJWUB1XPV+1p3ZYxzfvLQQD RTyO9imxiXzeTklUJywSzuOBS6Sq5wdVwL55Iu8Rapex9e/XirKl/pQ1Y5XDN8aDCqGF XXknVQ/0nIo8iYl73X9fCzZC7q5fUQOuhuuR6SYDRscrTD3jpdCnbTvHYUZUck6SDjzg hug3so0eLIqoGz97mIix9FSqovfbKY3P+mPf65X7Iifq26DAGJv76WF4HdMTBTUhpzJz hHqQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.37 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from snail.vger.email (snail.vger.email. [23.128.96.37]) by mx.google.com with ESMTPS id m18-20020a170902db1200b001cc0e39373bsi10562854plx.32.2023.11.15.08.33.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Nov 2023 08:33:11 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.37 as permitted sender) client-ip=23.128.96.37; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.37 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by snail.vger.email (Postfix) with ESMTP id 2BF6280A5F8D; Wed, 15 Nov 2023 08:31:15 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at snail.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232336AbjKOQaw (ORCPT + 29 others); Wed, 15 Nov 2023 11:30:52 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32932 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232414AbjKOQap (ORCPT ); Wed, 15 Nov 2023 11:30:45 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 68FB298 for ; Wed, 15 Nov 2023 08:30:41 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C680D15DB; Wed, 15 Nov 2023 08:31:26 -0800 (PST) Received: from e125769.cambridge.arm.com (e125769.cambridge.arm.com [10.1.196.26]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id F0A573F641; Wed, 15 Nov 2023 08:30:32 -0800 (PST) From: Ryan Roberts To: Catalin Marinas , Will Deacon , Ard Biesheuvel , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Zenghui Yu , Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Andrew Morton , Anshuman Khandual , Matthew Wilcox , Yu Zhao , Mark Rutland , David Hildenbrand , Kefeng Wang , John Hubbard , Zi Yan Cc: Ryan Roberts , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 01/14] mm: Batch-copy PTE ranges during fork() Date: Wed, 15 Nov 2023 16:30:05 +0000 Message-Id: <20231115163018.1303287-2-ryan.roberts@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231115163018.1303287-1-ryan.roberts@arm.com> References: <20231115163018.1303287-1-ryan.roberts@arm.com> MIME-Version: 1.0 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_BLOCKED,SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (snail.vger.email [0.0.0.0]); Wed, 15 Nov 2023 08:31:15 -0800 (PST) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1782648397583674316 X-GMAIL-MSGID: 1782648397583674316 Convert copy_pte_range() to copy a set of ptes in a batch. A given batch maps a physically contiguous block of memory, all belonging to the same folio, with the same permissions, and for shared mappings, the same dirty state. This will likely improve performance by a tiny amount due to batching the folio reference count management and calling set_ptes() rather than making individual calls to set_pte_at(). However, the primary motivation for this change is to reduce the number of tlb maintenance operations that the arm64 backend has to perform during fork, as it is about to add transparent support for the "contiguous bit" in its ptes. By write-protecting the parent using the new ptep_set_wrprotects() (note the 's' at the end) function, the backend can avoid having to unfold contig ranges of PTEs, which is expensive, when all ptes in the range are being write-protected. Similarly, by using set_ptes() rather than set_pte_at() to set up ptes in the child, the backend does not need to fold a contiguous range once they are all populated - they can be initially populated as a contiguous range in the first place. This change addresses the core-mm refactoring only, and introduces ptep_set_wrprotects() with a default implementation that calls ptep_set_wrprotect() for each pte in the range. A separate change will implement ptep_set_wrprotects() in the arm64 backend to realize the performance improvement as part of the work to enable contpte mappings. Signed-off-by: Ryan Roberts --- include/linux/pgtable.h | 13 +++ mm/memory.c | 175 +++++++++++++++++++++++++++++++--------- 2 files changed, 150 insertions(+), 38 deletions(-) diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h index af7639c3b0a3..1c50f8a0fdde 100644 --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -622,6 +622,19 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addres } #endif +#ifndef ptep_set_wrprotects +struct mm_struct; +static inline void ptep_set_wrprotects(struct mm_struct *mm, + unsigned long address, pte_t *ptep, + unsigned int nr) +{ + unsigned int i; + + for (i = 0; i < nr; i++, address += PAGE_SIZE, ptep++) + ptep_set_wrprotect(mm, address, ptep); +} +#endif + /* * On some architectures hardware does not set page access bit when accessing * memory page, it is responsibility of software setting this bit. It brings diff --git a/mm/memory.c b/mm/memory.c index 1f18ed4a5497..b7c8228883cf 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -921,46 +921,129 @@ copy_present_page(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma /* Uffd-wp needs to be delivered to dest pte as well */ pte = pte_mkuffd_wp(pte); set_pte_at(dst_vma->vm_mm, addr, dst_pte, pte); - return 0; + return 1; +} + +static inline unsigned long page_cont_mapped_vaddr(struct page *page, + struct page *anchor, unsigned long anchor_vaddr) +{ + unsigned long offset; + unsigned long vaddr; + + offset = (page_to_pfn(page) - page_to_pfn(anchor)) << PAGE_SHIFT; + vaddr = anchor_vaddr + offset; + + if (anchor > page) { + if (vaddr > anchor_vaddr) + return 0; + } else { + if (vaddr < anchor_vaddr) + return ULONG_MAX; + } + + return vaddr; +} + +static int folio_nr_pages_cont_mapped(struct folio *folio, + struct page *page, pte_t *pte, + unsigned long addr, unsigned long end, + pte_t ptent, bool *any_dirty) +{ + int floops; + int i; + unsigned long pfn; + pgprot_t prot; + struct page *folio_end; + + if (!folio_test_large(folio)) + return 1; + + folio_end = &folio->page + folio_nr_pages(folio); + end = min(page_cont_mapped_vaddr(folio_end, page, addr), end); + floops = (end - addr) >> PAGE_SHIFT; + pfn = page_to_pfn(page); + prot = pte_pgprot(pte_mkold(pte_mkclean(ptent))); + + *any_dirty = pte_dirty(ptent); + + pfn++; + pte++; + + for (i = 1; i < floops; i++) { + ptent = ptep_get(pte); + ptent = pte_mkold(pte_mkclean(ptent)); + + if (!pte_present(ptent) || pte_pfn(ptent) != pfn || + pgprot_val(pte_pgprot(ptent)) != pgprot_val(prot)) + break; + + if (pte_dirty(ptent)) + *any_dirty = true; + + pfn++; + pte++; + } + + return i; } /* - * Copy one pte. Returns 0 if succeeded, or -EAGAIN if one preallocated page - * is required to copy this pte. + * Copy set of contiguous ptes. Returns number of ptes copied if succeeded + * (always gte 1), or -EAGAIN if one preallocated page is required to copy the + * first pte. */ static inline int -copy_present_pte(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma, - pte_t *dst_pte, pte_t *src_pte, unsigned long addr, int *rss, - struct folio **prealloc) +copy_present_ptes(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma, + pte_t *dst_pte, pte_t *src_pte, + unsigned long addr, unsigned long end, + int *rss, struct folio **prealloc) { struct mm_struct *src_mm = src_vma->vm_mm; unsigned long vm_flags = src_vma->vm_flags; pte_t pte = ptep_get(src_pte); struct page *page; struct folio *folio; + int nr = 1; + bool anon; + bool any_dirty = pte_dirty(pte); + int i; page = vm_normal_page(src_vma, addr, pte); - if (page) + if (page) { folio = page_folio(page); - if (page && folio_test_anon(folio)) { - /* - * If this page may have been pinned by the parent process, - * copy the page immediately for the child so that we'll always - * guarantee the pinned page won't be randomly replaced in the - * future. - */ - folio_get(folio); - if (unlikely(page_try_dup_anon_rmap(page, false, src_vma))) { - /* Page may be pinned, we have to copy. */ - folio_put(folio); - return copy_present_page(dst_vma, src_vma, dst_pte, src_pte, - addr, rss, prealloc, page); + anon = folio_test_anon(folio); + nr = folio_nr_pages_cont_mapped(folio, page, src_pte, addr, + end, pte, &any_dirty); + + for (i = 0; i < nr; i++, page++) { + if (anon) { + /* + * If this page may have been pinned by the + * parent process, copy the page immediately for + * the child so that we'll always guarantee the + * pinned page won't be randomly replaced in the + * future. + */ + if (unlikely(page_try_dup_anon_rmap( + page, false, src_vma))) { + if (i != 0) + break; + /* Page may be pinned, we have to copy. */ + return copy_present_page( + dst_vma, src_vma, dst_pte, + src_pte, addr, rss, prealloc, + page); + } + rss[MM_ANONPAGES]++; + VM_BUG_ON(PageAnonExclusive(page)); + } else { + page_dup_file_rmap(page, false); + rss[mm_counter_file(page)]++; + } } - rss[MM_ANONPAGES]++; - } else if (page) { - folio_get(folio); - page_dup_file_rmap(page, false); - rss[mm_counter_file(page)]++; + + nr = i; + folio_ref_add(folio, nr); } /* @@ -968,24 +1051,28 @@ copy_present_pte(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma, * in the parent and the child */ if (is_cow_mapping(vm_flags) && pte_write(pte)) { - ptep_set_wrprotect(src_mm, addr, src_pte); + ptep_set_wrprotects(src_mm, addr, src_pte, nr); pte = pte_wrprotect(pte); } - VM_BUG_ON(page && folio_test_anon(folio) && PageAnonExclusive(page)); /* - * If it's a shared mapping, mark it clean in - * the child + * If it's a shared mapping, mark it clean in the child. If its a + * private mapping, mark it dirty in the child if _any_ of the parent + * mappings in the block were marked dirty. The contiguous block of + * mappings are all backed by the same folio, so if any are dirty then + * the whole folio is dirty. This allows us to determine the batch size + * without having to ever consider the dirty bit. See + * folio_nr_pages_cont_mapped(). */ - if (vm_flags & VM_SHARED) - pte = pte_mkclean(pte); - pte = pte_mkold(pte); + pte = pte_mkold(pte_mkclean(pte)); + if (!(vm_flags & VM_SHARED) && any_dirty) + pte = pte_mkdirty(pte); if (!userfaultfd_wp(dst_vma)) pte = pte_clear_uffd_wp(pte); - set_pte_at(dst_vma->vm_mm, addr, dst_pte, pte); - return 0; + set_ptes(dst_vma->vm_mm, addr, dst_pte, pte, nr); + return nr; } static inline struct folio *page_copy_prealloc(struct mm_struct *src_mm, @@ -1087,15 +1174,28 @@ copy_pte_range(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma, */ WARN_ON_ONCE(ret != -ENOENT); } - /* copy_present_pte() will clear `*prealloc' if consumed */ - ret = copy_present_pte(dst_vma, src_vma, dst_pte, src_pte, - addr, rss, &prealloc); + /* copy_present_ptes() will clear `*prealloc' if consumed */ + ret = copy_present_ptes(dst_vma, src_vma, dst_pte, src_pte, + addr, end, rss, &prealloc); + /* * If we need a pre-allocated page for this pte, drop the * locks, allocate, and try again. */ if (unlikely(ret == -EAGAIN)) break; + + /* + * Positive return value is the number of ptes copied. + */ + VM_WARN_ON_ONCE(ret < 1); + progress += 8 * ret; + ret--; + dst_pte += ret; + src_pte += ret; + addr += ret << PAGE_SHIFT; + ret = 0; + if (unlikely(prealloc)) { /* * pre-alloc page cannot be reused by next time so as @@ -1106,7 +1206,6 @@ copy_pte_range(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma, folio_put(prealloc); prealloc = NULL; } - progress += 8; } while (dst_pte++, src_pte++, addr += PAGE_SIZE, addr != end); arch_leave_lazy_mmu_mode(); From patchwork Wed Nov 15 16:30:06 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ryan Roberts X-Patchwork-Id: 165467 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b909:0:b0:403:3b70:6f57 with SMTP id t9csp2656290vqg; Wed, 15 Nov 2023 08:31:38 -0800 (PST) X-Google-Smtp-Source: AGHT+IHs7AY9Ddwtc2SFuHybPzUPFGBDiTY8l/EaajcGj/twcmglBlDUKpCZchokr/w3hLFMBUAh X-Received: by 2002:a17:90b:1804:b0:283:22f0:33a6 with SMTP id lw4-20020a17090b180400b0028322f033a6mr13582963pjb.42.1700065898037; Wed, 15 Nov 2023 08:31:38 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1700065898; cv=none; d=google.com; s=arc-20160816; b=FB982jZz50kHO6sd4yaXpred9ZQN6rRR/IgYAk+qFKSVtALbZ2eqhTajY58VMqjj9g wtSHUpXHjgE2xneIrPZ6kO+DAAliVGUd0O+sFsFF5S5SsvaW4u1bBOy69Pl+45PNU2f6 trR7QrFM2myGamU5r4h23zpvOfuRuyLtowZiVU+JfSIWDpdssQf6dhdFTMnTTYWBkl00 GKZebvOjA5A/pfRw5L+0M/N6J2p2/9g6FL3giGXyxrh8t0VIqzkifXcTq3OQQ0daaZCo 83aipmqCDOMgTwvpLIcaulw+KwCFHlk6gik/8TV8IKknaeD9RMSsvGF2DciFtdSNx7XJ /VfQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from; bh=xsNAviUmR5F8SYwTUIrOFJJg1yOMZo9+rbtTxHdvUqw=; fh=CVYMMnwSLqNeTtsgqDZkAN2xp/CPaSWpO0DiPqQVZ5w=; b=TUuHQ8wkCpxaprFy3VMaeGLD8Bt59IYBhvD7UosPJy/J2KhyUq16HKo20k8PtOlt85 k6w84NcSB4//kWV+4T9gBDZ327ctjqzKQ1NOQu4G/6ntnl+tOGNhBaIf4Cr1JpfIHBec ER5GW2TxlBt1dh9t02+lKCsk/tGxcqlaaBYqthzssftPyzfyTvYoW6IkVCstdbNTheF6 C68/hYbJwvwk9UB5aeXZVJTVHEtGimhXd30R7A0lJmckACEKOJ7pr2WxF5I5mMakiJbX uB6Yho86TSItWFT0WQ/mC63H53AstGrlowwS/L2Dg8nFvfOTpy7DiCTZ8zlVc2OaD70i x+3w== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.33 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from lipwig.vger.email (lipwig.vger.email. [23.128.96.33]) by mx.google.com with ESMTPS id oo5-20020a17090b1c8500b0028018c82e52si82583pjb.183.2023.11.15.08.31.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Nov 2023 08:31:38 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.33 as permitted sender) client-ip=23.128.96.33; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.33 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by lipwig.vger.email (Postfix) with ESMTP id 443F88160383; Wed, 15 Nov 2023 08:31:26 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at lipwig.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232296AbjKOQau (ORCPT + 29 others); Wed, 15 Nov 2023 11:30:50 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32898 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232319AbjKOQam (ORCPT ); Wed, 15 Nov 2023 11:30:42 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id A658898 for ; Wed, 15 Nov 2023 08:30:39 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 14F6A1595; Wed, 15 Nov 2023 08:31:25 -0800 (PST) Received: from e125769.cambridge.arm.com (e125769.cambridge.arm.com [10.1.196.26]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 5ABF03F73F; Wed, 15 Nov 2023 08:30:36 -0800 (PST) From: Ryan Roberts To: Catalin Marinas , Will Deacon , Ard Biesheuvel , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Zenghui Yu , Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Andrew Morton , Anshuman Khandual , Matthew Wilcox , Yu Zhao , Mark Rutland , David Hildenbrand , Kefeng Wang , John Hubbard , Zi Yan Cc: Ryan Roberts , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 02/14] arm64/mm: set_pte(): New layer to manage contig bit Date: Wed, 15 Nov 2023 16:30:06 +0000 Message-Id: <20231115163018.1303287-3-ryan.roberts@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231115163018.1303287-1-ryan.roberts@arm.com> References: <20231115163018.1303287-1-ryan.roberts@arm.com> MIME-Version: 1.0 X-Spam-Status: No, score=-0.8 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lipwig.vger.email Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (lipwig.vger.email [0.0.0.0]); Wed, 15 Nov 2023 08:31:26 -0800 (PST) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1782648299147544437 X-GMAIL-MSGID: 1782648299147544437 Create a new layer for the in-table PTE manipulation APIs. For now, The existing API is prefixed with double underscore to become the arch-private API and the public API is just a simple wrapper that calls the private API. The public API implementation will subsequently be used to transparently manipulate the contiguous bit where appropriate. But since there are already some contig-aware users (e.g. hugetlb, kernel mapper), we must first ensure those users use the private API directly so that the future contig-bit manipulations in the public API do not interfere with those existing uses. Signed-off-by: Ryan Roberts --- arch/arm64/include/asm/pgtable.h | 12 ++++++++---- arch/arm64/kernel/efi.c | 2 +- arch/arm64/mm/fixmap.c | 2 +- arch/arm64/mm/kasan_init.c | 4 ++-- arch/arm64/mm/mmu.c | 2 +- arch/arm64/mm/pageattr.c | 2 +- arch/arm64/mm/trans_pgd.c | 4 ++-- 7 files changed, 16 insertions(+), 12 deletions(-) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index b19a8aee684c..650d4f4bb6dc 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -93,7 +93,8 @@ static inline pteval_t __phys_to_pte_val(phys_addr_t phys) __pte(__phys_to_pte_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)) #define pte_none(pte) (!pte_val(pte)) -#define pte_clear(mm,addr,ptep) set_pte(ptep, __pte(0)) +#define pte_clear(mm, addr, ptep) \ + __set_pte(ptep, __pte(0)) #define pte_page(pte) (pfn_to_page(pte_pfn(pte))) /* @@ -261,7 +262,7 @@ static inline pte_t pte_mkdevmap(pte_t pte) return set_pte_bit(pte, __pgprot(PTE_DEVMAP | PTE_SPECIAL)); } -static inline void set_pte(pte_t *ptep, pte_t pte) +static inline void __set_pte(pte_t *ptep, pte_t pte) { WRITE_ONCE(*ptep, pte); @@ -350,7 +351,7 @@ static inline void set_ptes(struct mm_struct *mm, for (;;) { __check_safe_pte_update(mm, ptep, pte); - set_pte(ptep, pte); + __set_pte(ptep, pte); if (--nr == 0) break; ptep++; @@ -534,7 +535,7 @@ static inline void __set_pte_at(struct mm_struct *mm, { __sync_cache_and_tags(pte, nr); __check_safe_pte_update(mm, ptep, pte); - set_pte(ptep, pte); + __set_pte(ptep, pte); } static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr, @@ -1118,6 +1119,9 @@ extern pte_t ptep_modify_prot_start(struct vm_area_struct *vma, extern void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep, pte_t old_pte, pte_t new_pte); + +#define set_pte __set_pte + #endif /* !__ASSEMBLY__ */ #endif /* __ASM_PGTABLE_H */ diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c index 0228001347be..44288a12fc6c 100644 --- a/arch/arm64/kernel/efi.c +++ b/arch/arm64/kernel/efi.c @@ -111,7 +111,7 @@ static int __init set_permissions(pte_t *ptep, unsigned long addr, void *data) pte = set_pte_bit(pte, __pgprot(PTE_PXN)); else if (system_supports_bti_kernel() && spd->has_bti) pte = set_pte_bit(pte, __pgprot(PTE_GP)); - set_pte(ptep, pte); + __set_pte(ptep, pte); return 0; } diff --git a/arch/arm64/mm/fixmap.c b/arch/arm64/mm/fixmap.c index c0a3301203bd..51cd4501816d 100644 --- a/arch/arm64/mm/fixmap.c +++ b/arch/arm64/mm/fixmap.c @@ -121,7 +121,7 @@ void __set_fixmap(enum fixed_addresses idx, ptep = fixmap_pte(addr); if (pgprot_val(flags)) { - set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, flags)); + __set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, flags)); } else { pte_clear(&init_mm, addr, ptep); flush_tlb_kernel_range(addr, addr+PAGE_SIZE); diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c index 555285ebd5af..5eade712e9e5 100644 --- a/arch/arm64/mm/kasan_init.c +++ b/arch/arm64/mm/kasan_init.c @@ -112,7 +112,7 @@ static void __init kasan_pte_populate(pmd_t *pmdp, unsigned long addr, if (!early) memset(__va(page_phys), KASAN_SHADOW_INIT, PAGE_SIZE); next = addr + PAGE_SIZE; - set_pte(ptep, pfn_pte(__phys_to_pfn(page_phys), PAGE_KERNEL)); + __set_pte(ptep, pfn_pte(__phys_to_pfn(page_phys), PAGE_KERNEL)); } while (ptep++, addr = next, addr != end && pte_none(READ_ONCE(*ptep))); } @@ -266,7 +266,7 @@ static void __init kasan_init_shadow(void) * so we should make sure that it maps the zero page read-only. */ for (i = 0; i < PTRS_PER_PTE; i++) - set_pte(&kasan_early_shadow_pte[i], + __set_pte(&kasan_early_shadow_pte[i], pfn_pte(sym_to_pfn(kasan_early_shadow_page), PAGE_KERNEL_RO)); diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 15f6347d23b6..e884279b268e 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -178,7 +178,7 @@ static void init_pte(pmd_t *pmdp, unsigned long addr, unsigned long end, do { pte_t old_pte = READ_ONCE(*ptep); - set_pte(ptep, pfn_pte(__phys_to_pfn(phys), prot)); + __set_pte(ptep, pfn_pte(__phys_to_pfn(phys), prot)); /* * After the PTE entry has been populated once, we diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c index 8e2017ba5f1b..057097acf9e0 100644 --- a/arch/arm64/mm/pageattr.c +++ b/arch/arm64/mm/pageattr.c @@ -41,7 +41,7 @@ static int change_page_range(pte_t *ptep, unsigned long addr, void *data) pte = clear_pte_bit(pte, cdata->clear_mask); pte = set_pte_bit(pte, cdata->set_mask); - set_pte(ptep, pte); + __set_pte(ptep, pte); return 0; } diff --git a/arch/arm64/mm/trans_pgd.c b/arch/arm64/mm/trans_pgd.c index 7b14df3c6477..230b607cf881 100644 --- a/arch/arm64/mm/trans_pgd.c +++ b/arch/arm64/mm/trans_pgd.c @@ -41,7 +41,7 @@ static void _copy_pte(pte_t *dst_ptep, pte_t *src_ptep, unsigned long addr) * read only (code, rodata). Clear the RDONLY bit from * the temporary mappings we use during restore. */ - set_pte(dst_ptep, pte_mkwrite_novma(pte)); + __set_pte(dst_ptep, pte_mkwrite_novma(pte)); } else if ((debug_pagealloc_enabled() || is_kfence_address((void *)addr)) && !pte_none(pte)) { /* @@ -55,7 +55,7 @@ static void _copy_pte(pte_t *dst_ptep, pte_t *src_ptep, unsigned long addr) */ BUG_ON(!pfn_valid(pte_pfn(pte))); - set_pte(dst_ptep, pte_mkpresent(pte_mkwrite_novma(pte))); + __set_pte(dst_ptep, pte_mkpresent(pte_mkwrite_novma(pte))); } } From patchwork Wed Nov 15 16:30:07 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ryan Roberts X-Patchwork-Id: 165468 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b909:0:b0:403:3b70:6f57 with SMTP id t9csp2656622vqg; Wed, 15 Nov 2023 08:32:03 -0800 (PST) X-Google-Smtp-Source: AGHT+IELnma7FDSzz+NxPuVke7HMKMT14jm7ZmoLhvd35oYVxCSAITTBlKc63rvJWgMb5iOREHxv X-Received: by 2002:a05:6a00:1593:b0:6be:2649:8c6b with SMTP id u19-20020a056a00159300b006be26498c6bmr14257690pfk.32.1700065923605; Wed, 15 Nov 2023 08:32:03 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1700065923; cv=none; d=google.com; s=arc-20160816; b=jjYX4FlCnw+EeJjAjanX3HDJW9p93oL8x8IxVlkfApIW3/kaWy27AaI3YWrHczK1L9 GNHN1OrZKv4cR/+/eAXY01K39C5GPxEIR7JKTuzDHpNCNJJpbZSwzRF0W5amXfYvyDAT mlcw7PUlXNy2suQD+0FBvAwfCDQHddK2kE/Mwkm600jyQV3I3PIi6b396+B3aKjJEBUW tdCsL08v0GpH3B3KneqRIpO/vupnWVPBmTGuZarDTJ4l3sFLW+lspdLgkQTcokfW6YiF GnmqmQGLsJ0qC5+3paFZBCgohvoYd2I/Hgbpn/e8pCStKj6b/TR9t0JbFmHFjX9eCLM4 fssw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from; bh=nX6cppQWykzFlGLv1/MzIfjs0FHZmU2vVGTO0jGCe+w=; fh=CVYMMnwSLqNeTtsgqDZkAN2xp/CPaSWpO0DiPqQVZ5w=; b=L4ZuAJ5VFmnhfRLTZS69hyoC18W6NPucGZNyQSc2UgYpnASVAZbZoByKt62cUdJ6AM 6zO9EdXB/OYHv0DPQhBYCE1caaVz43YPVl5FRZYWBgpYJfBSRGPQ47YzV0lPe2Mt1yIh GsSgv3hg9+BRfQkak3ppXKvY5Gp1SoxDfNf9p+ePjcS5IZHKvAZAci5VsMykoqLisLqN kT+ndkKM85csmtYtZM82x0fpPQcAE+TGS3gbRZqqiSMaLndy5rEbQv9U6Hf+P/xdh0EY FRx+QdnatcBqkBG0sYpMAIDf3Wsyom9gbgdRSP1PNbvbvcHE/YMl6ldeb5O6zF2cOkwt olXQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.32 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from agentk.vger.email (agentk.vger.email. [23.128.96.32]) by mx.google.com with ESMTPS id h16-20020a056a00231000b0068c7033a5f5si10769761pfh.74.2023.11.15.08.32.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Nov 2023 08:32:03 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.32 as permitted sender) client-ip=23.128.96.32; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.32 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by agentk.vger.email (Postfix) with ESMTP id 0E93A80C9DA7; Wed, 15 Nov 2023 08:31:53 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at agentk.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232307AbjKOQaz (ORCPT + 29 others); Wed, 15 Nov 2023 11:30:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32966 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232267AbjKOQar (ORCPT ); Wed, 15 Nov 2023 11:30:47 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id E965BE6 for ; Wed, 15 Nov 2023 08:30:42 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 573671650; Wed, 15 Nov 2023 08:31:28 -0800 (PST) Received: from e125769.cambridge.arm.com (e125769.cambridge.arm.com [10.1.196.26]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9D64E3F73F; Wed, 15 Nov 2023 08:30:39 -0800 (PST) From: Ryan Roberts To: Catalin Marinas , Will Deacon , Ard Biesheuvel , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Zenghui Yu , Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Andrew Morton , Anshuman Khandual , Matthew Wilcox , Yu Zhao , Mark Rutland , David Hildenbrand , Kefeng Wang , John Hubbard , Zi Yan Cc: Ryan Roberts , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 03/14] arm64/mm: set_ptes()/set_pte_at(): New layer to manage contig bit Date: Wed, 15 Nov 2023 16:30:07 +0000 Message-Id: <20231115163018.1303287-4-ryan.roberts@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231115163018.1303287-1-ryan.roberts@arm.com> References: <20231115163018.1303287-1-ryan.roberts@arm.com> MIME-Version: 1.0 X-Spam-Status: No, score=-0.8 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on agentk.vger.email Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (agentk.vger.email [0.0.0.0]); Wed, 15 Nov 2023 08:31:53 -0800 (PST) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1782648325981782958 X-GMAIL-MSGID: 1782648325981782958 Create a new layer for the in-table PTE manipulation APIs. For now, The existing API is prefixed with double underscore to become the arch-private API and the public API is just a simple wrapper that calls the private API. The public API implementation will subsequently be used to transparently manipulate the contiguous bit where appropriate. But since there are already some contig-aware users (e.g. hugetlb, kernel mapper), we must first ensure those users use the private API directly so that the future contig-bit manipulations in the public API do not interfere with those existing uses. set_pte_at() is a core macro that forwards to set_ptes() (with nr=1). Instead of creating a __set_pte_at() internal macro, convert all arch users to use set_ptes()/__set_ptes() directly, as appropriate. Callers in hugetlb may benefit from calling __set_ptes() once for their whole range rather than managing their own loop. This is left for future improvement. Signed-off-by: Ryan Roberts --- arch/arm64/include/asm/pgtable.h | 10 +++++----- arch/arm64/kernel/mte.c | 2 +- arch/arm64/kvm/guest.c | 2 +- arch/arm64/mm/fault.c | 2 +- arch/arm64/mm/hugetlbpage.c | 10 +++++----- 5 files changed, 13 insertions(+), 13 deletions(-) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 650d4f4bb6dc..323ec91add60 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -342,9 +342,9 @@ static inline void __sync_cache_and_tags(pte_t pte, unsigned int nr_pages) mte_sync_tags(pte, nr_pages); } -static inline void set_ptes(struct mm_struct *mm, - unsigned long __always_unused addr, - pte_t *ptep, pte_t pte, unsigned int nr) +static inline void __set_ptes(struct mm_struct *mm, + unsigned long __always_unused addr, + pte_t *ptep, pte_t pte, unsigned int nr) { page_table_check_ptes_set(mm, ptep, pte, nr); __sync_cache_and_tags(pte, nr); @@ -358,7 +358,6 @@ static inline void set_ptes(struct mm_struct *mm, pte_val(pte) += PAGE_SIZE; } } -#define set_ptes set_ptes /* * Huge pte definitions. @@ -1067,7 +1066,7 @@ static inline void arch_swap_restore(swp_entry_t entry, struct folio *folio) #endif /* CONFIG_ARM64_MTE */ /* - * On AArch64, the cache coherency is handled via the set_pte_at() function. + * On AArch64, the cache coherency is handled via the __set_ptes() function. */ static inline void update_mmu_cache_range(struct vm_fault *vmf, struct vm_area_struct *vma, unsigned long addr, pte_t *ptep, @@ -1121,6 +1120,7 @@ extern void ptep_modify_prot_commit(struct vm_area_struct *vma, pte_t old_pte, pte_t new_pte); #define set_pte __set_pte +#define set_ptes __set_ptes #endif /* !__ASSEMBLY__ */ diff --git a/arch/arm64/kernel/mte.c b/arch/arm64/kernel/mte.c index a41ef3213e1e..dcdcccd40891 100644 --- a/arch/arm64/kernel/mte.c +++ b/arch/arm64/kernel/mte.c @@ -67,7 +67,7 @@ int memcmp_pages(struct page *page1, struct page *page2) /* * If the page content is identical but at least one of the pages is * tagged, return non-zero to avoid KSM merging. If only one of the - * pages is tagged, set_pte_at() may zero or change the tags of the + * pages is tagged, __set_ptes() may zero or change the tags of the * other page via mte_sync_tags(). */ if (page_mte_tagged(page1) || page_mte_tagged(page2)) diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index aaf1d4939739..629145fd3161 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -1072,7 +1072,7 @@ int kvm_vm_ioctl_mte_copy_tags(struct kvm *kvm, } else { /* * Only locking to serialise with a concurrent - * set_pte_at() in the VMM but still overriding the + * __set_ptes() in the VMM but still overriding the * tags, hence ignoring the return value. */ try_page_mte_tagging(page); diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index 460d799e1296..a287c1dea871 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -205,7 +205,7 @@ static void show_pte(unsigned long addr) * * It needs to cope with hardware update of the accessed/dirty state by other * agents in the system and can safely skip the __sync_icache_dcache() call as, - * like set_pte_at(), the PTE is never changed from no-exec to exec here. + * like __set_ptes(), the PTE is never changed from no-exec to exec here. * * Returns whether or not the PTE actually changed. */ diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c index f5aae342632c..741cb53672fd 100644 --- a/arch/arm64/mm/hugetlbpage.c +++ b/arch/arm64/mm/hugetlbpage.c @@ -254,12 +254,12 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, if (!pte_present(pte)) { for (i = 0; i < ncontig; i++, ptep++, addr += pgsize) - set_pte_at(mm, addr, ptep, pte); + __set_ptes(mm, addr, ptep, pte, 1); return; } if (!pte_cont(pte)) { - set_pte_at(mm, addr, ptep, pte); + __set_ptes(mm, addr, ptep, pte, 1); return; } @@ -270,7 +270,7 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, clear_flush(mm, addr, ptep, pgsize, ncontig); for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn) - set_pte_at(mm, addr, ptep, pfn_pte(pfn, hugeprot)); + __set_ptes(mm, addr, ptep, pfn_pte(pfn, hugeprot), 1); } pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, @@ -478,7 +478,7 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma, hugeprot = pte_pgprot(pte); for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn) - set_pte_at(mm, addr, ptep, pfn_pte(pfn, hugeprot)); + __set_ptes(mm, addr, ptep, pfn_pte(pfn, hugeprot), 1); return 1; } @@ -507,7 +507,7 @@ void huge_ptep_set_wrprotect(struct mm_struct *mm, pfn = pte_pfn(pte); for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn) - set_pte_at(mm, addr, ptep, pfn_pte(pfn, hugeprot)); + __set_ptes(mm, addr, ptep, pfn_pte(pfn, hugeprot), 1); } pte_t huge_ptep_clear_flush(struct vm_area_struct *vma, From patchwork Wed Nov 15 16:30:08 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ryan Roberts X-Patchwork-Id: 165473 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b909:0:b0:403:3b70:6f57 with SMTP id t9csp2657390vqg; Wed, 15 Nov 2023 08:33:18 -0800 (PST) X-Google-Smtp-Source: AGHT+IE1KsWYewsAp6EFeNmNCN2Ft7x+vvzWVUAR/94umakCceeFdbuS1eTry2/86M4v4wsignoc X-Received: by 2002:aa7:80c8:0:b0:6ca:af85:f07 with SMTP id a8-20020aa780c8000000b006caaf850f07mr940822pfn.20.1700065998488; Wed, 15 Nov 2023 08:33:18 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1700065998; cv=none; d=google.com; s=arc-20160816; b=SLh3xpSBMDQ9oY/20qczHwHb0ZX9VPvP6eD3pMtMS7Bwh2fIjaCNyqBgMk4NfHf2Y0 RYBVb2f/bKq0rFBdrnkU1wuorKTNTEhG/kzBOwdsu91I6Xt5n7fCJ25XlM+rZjQ3Qj8H y7xzDBD7H8r1ZEzl+8cuYYTb+LCX8Vlw92z9nolBJhdMQS/S1VX2kSPkM0xg6rXFPImO GzI38SkmlphjnIxq5qEWmknMDHrtqlDcqpSHGZMU8cdOsAtxfYndMVOvtdR9E4JVL+mr KdYeCr2u58T2k9judcvUiy625ZrQaJsH/8agI9MsSeqm/kP42SnCWFix9l33JrGGF8el 08xg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from; bh=YwPKQQiak6Wq4SeQDrdHtDBJcvIfgSIZ07B41IMN5A0=; fh=CVYMMnwSLqNeTtsgqDZkAN2xp/CPaSWpO0DiPqQVZ5w=; b=xzwOJ4mb7XtqVxNJvUfnlOMS7mPw9FUF74stuDRcDdAQRJkSs/mxI1ea1/JhYHA3MU veT+f0nOIGbbmwuqbb2nZOP5LvdiL0Jye0DgPbK3NYFQo69Zr2ttp17bHxIXzexdUUqi k6GcmceiI0gYnBmdWlV1Sf8zSkhEWF4nAHgEkVao6Nw2st2Y0SXnb058YOX3R3+xfcHg 2MNx2Co12KieSYsilrNBg7O7jCjmq41L+EihHQX+Hs0i1haffW73raqeeB7MqmLEiQ/i zvprBm5qwm6/G+u28FPmf+maM4vGRSkhcwBQwVFMQkB3lFD1ylRukG4g1wEygYqqYkDn lMqQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.37 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from snail.vger.email (snail.vger.email. [23.128.96.37]) by mx.google.com with ESMTPS id v38-20020a634826000000b00577448019b5si10286003pga.276.2023.11.15.08.33.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Nov 2023 08:33:18 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.37 as permitted sender) client-ip=23.128.96.37; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.37 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by snail.vger.email (Postfix) with ESMTP id 443B080D7E40; Wed, 15 Nov 2023 08:31:20 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at snail.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232487AbjKOQa5 (ORCPT + 29 others); Wed, 15 Nov 2023 11:30:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32978 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232255AbjKOQat (ORCPT ); Wed, 15 Nov 2023 11:30:49 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 3E9C4AB for ; Wed, 15 Nov 2023 08:30:46 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 9A75DDA7; Wed, 15 Nov 2023 08:31:31 -0800 (PST) Received: from e125769.cambridge.arm.com (e125769.cambridge.arm.com [10.1.196.26]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E084A3F641; Wed, 15 Nov 2023 08:30:42 -0800 (PST) From: Ryan Roberts To: Catalin Marinas , Will Deacon , Ard Biesheuvel , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Zenghui Yu , Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Andrew Morton , Anshuman Khandual , Matthew Wilcox , Yu Zhao , Mark Rutland , David Hildenbrand , Kefeng Wang , John Hubbard , Zi Yan Cc: Ryan Roberts , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 04/14] arm64/mm: pte_clear(): New layer to manage contig bit Date: Wed, 15 Nov 2023 16:30:08 +0000 Message-Id: <20231115163018.1303287-5-ryan.roberts@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231115163018.1303287-1-ryan.roberts@arm.com> References: <20231115163018.1303287-1-ryan.roberts@arm.com> MIME-Version: 1.0 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_BLOCKED,SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (snail.vger.email [0.0.0.0]); Wed, 15 Nov 2023 08:31:20 -0800 (PST) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1782648404386936314 X-GMAIL-MSGID: 1782648404386936314 Create a new layer for the in-table PTE manipulation APIs. For now, The existing API is prefixed with double underscore to become the arch-private API and the public API is just a simple wrapper that calls the private API. The public API implementation will subsequently be used to transparently manipulate the contiguous bit where appropriate. But since there are already some contig-aware users (e.g. hugetlb, kernel mapper), we must first ensure those users use the private API directly so that the future contig-bit manipulations in the public API do not interfere with those existing uses. Signed-off-by: Ryan Roberts --- arch/arm64/include/asm/pgtable.h | 3 ++- arch/arm64/mm/fixmap.c | 2 +- arch/arm64/mm/hugetlbpage.c | 2 +- arch/arm64/mm/mmu.c | 2 +- 4 files changed, 5 insertions(+), 4 deletions(-) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 323ec91add60..1464e990580a 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -93,7 +93,7 @@ static inline pteval_t __phys_to_pte_val(phys_addr_t phys) __pte(__phys_to_pte_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)) #define pte_none(pte) (!pte_val(pte)) -#define pte_clear(mm, addr, ptep) \ +#define __pte_clear(mm, addr, ptep) \ __set_pte(ptep, __pte(0)) #define pte_page(pte) (pfn_to_page(pte_pfn(pte))) @@ -1121,6 +1121,7 @@ extern void ptep_modify_prot_commit(struct vm_area_struct *vma, #define set_pte __set_pte #define set_ptes __set_ptes +#define pte_clear __pte_clear #endif /* !__ASSEMBLY__ */ diff --git a/arch/arm64/mm/fixmap.c b/arch/arm64/mm/fixmap.c index 51cd4501816d..bfc02568805a 100644 --- a/arch/arm64/mm/fixmap.c +++ b/arch/arm64/mm/fixmap.c @@ -123,7 +123,7 @@ void __set_fixmap(enum fixed_addresses idx, if (pgprot_val(flags)) { __set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, flags)); } else { - pte_clear(&init_mm, addr, ptep); + __pte_clear(&init_mm, addr, ptep); flush_tlb_kernel_range(addr, addr+PAGE_SIZE); } } diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c index 741cb53672fd..510b2d4b89a9 100644 --- a/arch/arm64/mm/hugetlbpage.c +++ b/arch/arm64/mm/hugetlbpage.c @@ -400,7 +400,7 @@ void huge_pte_clear(struct mm_struct *mm, unsigned long addr, ncontig = num_contig_ptes(sz, &pgsize); for (i = 0; i < ncontig; i++, addr += pgsize, ptep++) - pte_clear(mm, addr, ptep); + __pte_clear(mm, addr, ptep); } pte_t huge_ptep_get_and_clear(struct mm_struct *mm, diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index e884279b268e..080e9b50f595 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -859,7 +859,7 @@ static void unmap_hotplug_pte_range(pmd_t *pmdp, unsigned long addr, continue; WARN_ON(!pte_present(pte)); - pte_clear(&init_mm, addr, ptep); + __pte_clear(&init_mm, addr, ptep); flush_tlb_kernel_range(addr, addr + PAGE_SIZE); if (free_mapped) free_hotplug_page_range(pte_page(pte), From patchwork Wed Nov 15 16:30:09 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ryan Roberts X-Patchwork-Id: 165474 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b909:0:b0:403:3b70:6f57 with SMTP id t9csp2657402vqg; Wed, 15 Nov 2023 08:33:19 -0800 (PST) X-Google-Smtp-Source: AGHT+IEyMyiiUq74IMY1AzzDanAQJi4r0ZaNj7duiolGei4t5bQ90Fn0y1b/vp4pLsa7P3CTa4HS X-Received: by 2002:a05:6e02:1d13:b0:359:3d9a:2837 with SMTP id i19-20020a056e021d1300b003593d9a2837mr18538621ila.2.1700065999485; Wed, 15 Nov 2023 08:33:19 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1700065999; cv=none; d=google.com; s=arc-20160816; b=MJzjAqJ0iy2XmALwpjgDgeiRXpeYEYZhJfJMVK8qfYG2PFmjxbByypGWLK/MAYlAKh 7icXWa9pOSHSQtQPjZ0aoshCz9AorDG/z9dvaPsmXHUleQ+FuZaDv640i57Yds0C86ws FzXIJNkbYmZB4NVljDyBpbpEWEdU/lbaNTSq7fWDkXQ68tawiM5s1nn4+1njiRM5CsLV N/3XAfCBm/mrhIx5EdYJGSU/uqb+4KkgRq8Xq9GZxyJahLSoZuGBSRNofs82zTHHBKmU pRxpyNctEeKaPn3weXDtb7tQpB7k8GUn6s7zrzqbX5fy4gKz5+3TuDhSl84uJ5u2vQPj wSBA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from; bh=g7RKJubwZGuwzYxXs5rxmgWa6Yt6X+DHtCiVrTsfCrg=; fh=CVYMMnwSLqNeTtsgqDZkAN2xp/CPaSWpO0DiPqQVZ5w=; b=zNX1xyxJSN3d7/pMMMGr4EqYy0g1NSzmL/CEa+Y2K11rjo0mNpe7kGG/UchioXnXrP Jy147sGv0pI1C0+xMsMs+uK0hvmwv4wbT/gm+k/ggm9z1tL78hcmrXp1D7h09ZSLyjb5 7+HzubOMiX7TRrE0BRL9RrbDyu70ccMSG95c/8qJ6X9Xo4zOHkIUFTkkrVO8nmmUnwH1 bP1bDWoJFoeLGVpiCnPwrFgml9BJR8pM2AQrOJmWAMAy00rd1q4BJcp6Lhjt7Aoerx+O pq7UyIRSVyEMt+syB8VpQnV3dsKdmSKD9bKvmC9J66PYXgF7mQLwYNVE+GCA5qtvASFL 2dAQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.37 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from snail.vger.email (snail.vger.email. [23.128.96.37]) by mx.google.com with ESMTPS id x28-20020a634a1c000000b0057828b85afdsi10039474pga.795.2023.11.15.08.33.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Nov 2023 08:33:19 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.37 as permitted sender) client-ip=23.128.96.37; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.37 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by snail.vger.email (Postfix) with ESMTP id ED3EB811F13A; Wed, 15 Nov 2023 08:31:30 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at snail.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232406AbjKOQbG (ORCPT + 29 others); Wed, 15 Nov 2023 11:31:06 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37744 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232414AbjKOQay (ORCPT ); Wed, 15 Nov 2023 11:30:54 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 82B611A4 for ; Wed, 15 Nov 2023 08:30:49 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id DD98E1595; Wed, 15 Nov 2023 08:31:34 -0800 (PST) Received: from e125769.cambridge.arm.com (e125769.cambridge.arm.com [10.1.196.26]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 2F7823F641; Wed, 15 Nov 2023 08:30:46 -0800 (PST) From: Ryan Roberts To: Catalin Marinas , Will Deacon , Ard Biesheuvel , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Zenghui Yu , Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Andrew Morton , Anshuman Khandual , Matthew Wilcox , Yu Zhao , Mark Rutland , David Hildenbrand , Kefeng Wang , John Hubbard , Zi Yan Cc: Ryan Roberts , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 05/14] arm64/mm: ptep_get_and_clear(): New layer to manage contig bit Date: Wed, 15 Nov 2023 16:30:09 +0000 Message-Id: <20231115163018.1303287-6-ryan.roberts@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231115163018.1303287-1-ryan.roberts@arm.com> References: <20231115163018.1303287-1-ryan.roberts@arm.com> MIME-Version: 1.0 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_BLOCKED,SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (snail.vger.email [0.0.0.0]); Wed, 15 Nov 2023 08:31:31 -0800 (PST) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1782648405864519875 X-GMAIL-MSGID: 1782648405864519875 Create a new layer for the in-table PTE manipulation APIs. For now, The existing API is prefixed with double underscore to become the arch-private API and the public API is just a simple wrapper that calls the private API. The public API implementation will subsequently be used to transparently manipulate the contiguous bit where appropriate. But since there are already some contig-aware users (e.g. hugetlb, kernel mapper), we must first ensure those users use the private API directly so that the future contig-bit manipulations in the public API do not interfere with those existing uses. Signed-off-by: Ryan Roberts --- arch/arm64/include/asm/pgtable.h | 5 +++-- arch/arm64/mm/hugetlbpage.c | 6 +++--- 2 files changed, 6 insertions(+), 5 deletions(-) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 1464e990580a..994597a0bb0f 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -941,8 +941,7 @@ static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma, } #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ -#define __HAVE_ARCH_PTEP_GET_AND_CLEAR -static inline pte_t ptep_get_and_clear(struct mm_struct *mm, +static inline pte_t __ptep_get_and_clear(struct mm_struct *mm, unsigned long address, pte_t *ptep) { pte_t pte = __pte(xchg_relaxed(&pte_val(*ptep), 0)); @@ -1122,6 +1121,8 @@ extern void ptep_modify_prot_commit(struct vm_area_struct *vma, #define set_pte __set_pte #define set_ptes __set_ptes #define pte_clear __pte_clear +#define __HAVE_ARCH_PTEP_GET_AND_CLEAR +#define ptep_get_and_clear __ptep_get_and_clear #endif /* !__ASSEMBLY__ */ diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c index 510b2d4b89a9..c2a753541d13 100644 --- a/arch/arm64/mm/hugetlbpage.c +++ b/arch/arm64/mm/hugetlbpage.c @@ -188,7 +188,7 @@ static pte_t get_clear_contig(struct mm_struct *mm, unsigned long i; for (i = 0; i < ncontig; i++, addr += pgsize, ptep++) { - pte_t pte = ptep_get_and_clear(mm, addr, ptep); + pte_t pte = __ptep_get_and_clear(mm, addr, ptep); /* * If HW_AFDBM is enabled, then the HW could turn on @@ -236,7 +236,7 @@ static void clear_flush(struct mm_struct *mm, unsigned long i, saddr = addr; for (i = 0; i < ncontig; i++, addr += pgsize, ptep++) - ptep_clear(mm, addr, ptep); + __ptep_get_and_clear(mm, addr, ptep); flush_tlb_range(&vma, saddr, addr); } @@ -411,7 +411,7 @@ pte_t huge_ptep_get_and_clear(struct mm_struct *mm, pte_t orig_pte = ptep_get(ptep); if (!pte_cont(orig_pte)) - return ptep_get_and_clear(mm, addr, ptep); + return __ptep_get_and_clear(mm, addr, ptep); ncontig = find_num_contig(mm, addr, ptep, &pgsize); From patchwork Wed Nov 15 16:30:10 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ryan Roberts X-Patchwork-Id: 165469 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b909:0:b0:403:3b70:6f57 with SMTP id t9csp2657117vqg; Wed, 15 Nov 2023 08:32:50 -0800 (PST) X-Google-Smtp-Source: AGHT+IFtTg/7nq6u3rMaapDexTDl+8QqPvd228C/jddVS5D86RHe7itQVDVv9iijpbspS/gvfqkM X-Received: by 2002:a17:902:b788:b0:1c9:e2ed:66fe with SMTP id e8-20020a170902b78800b001c9e2ed66femr4504823pls.52.1700065970619; Wed, 15 Nov 2023 08:32:50 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1700065970; cv=none; d=google.com; s=arc-20160816; b=hRtjKMGSNExXnfTxGa3iFBLG/EyC1PFJzgkVLy2xah7vXi3cipQ0OggNj/j6uQRAiV fnE5jgsYgUoEUESFJk/tlNP3O34ICwyFh8HTceXNHFrxHhQp3no38Sh1XfmeQEmydrdg q4R279tQJKcXQWfmWKehwXCXarlmPKRabVrGOyyJlLku/P4pijmWV4lsaOpba8CiMQXn 0uwArFm5ru264tnw9X6jRXiiki2LSiT3XlquYoov2G309pPU3J+69O30B9KY14I8id7V Wje9jGlVSz+pJbtgSJSxn4dMhJyMclsOY5Skxn9SJ5jktj4V6GDuk6hHi8wJWp9a6Kmb H7zw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from; bh=ah49fTPYg1kjKkibdjx5mHLTxVRVE+SlIK3JQIq5PE4=; fh=CVYMMnwSLqNeTtsgqDZkAN2xp/CPaSWpO0DiPqQVZ5w=; b=iUEaeyt/bazXF/SPFQz+W2JMHoFIAVGaW8AL8O6j4fYFNRPgYMML0Eji1toxASCrQI TqLteOQhQvvVbzgON8EF/gC0kUqNRlU3vSBuNnlSBBk8ytSpefs//pIxozRTC93NMy3Q Pef3bN1PmXCG6FNcFI1kGktoWoluDRy8zvsJ9UOHxOa9T5wW9aETqFwIZcjNhc5sAf02 f1a8A4Jmk8BfhYbXrqyRzOU50lRIW5eILml3GKuPVvfxyUwCjeabhxotyWre2vVuK8bB Vcdz2pnfzmhUC9tVequu5thBPWLOZj9ihR1wow0Uid5BSsWqO1owqPeXvHnSmtAQC332 kfwA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.33 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from lipwig.vger.email (lipwig.vger.email. [23.128.96.33]) by mx.google.com with ESMTPS id lm3-20020a170903298300b001bdd0d0530dsi11076286plb.129.2023.11.15.08.32.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Nov 2023 08:32:50 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.33 as permitted sender) client-ip=23.128.96.33; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.33 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by lipwig.vger.email (Postfix) with ESMTP id 624E381552C1; Wed, 15 Nov 2023 08:32:43 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at lipwig.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232661AbjKOQbJ (ORCPT + 29 others); Wed, 15 Nov 2023 11:31:09 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37670 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232449AbjKOQbE (ORCPT ); Wed, 15 Nov 2023 11:31:04 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id C5B0DFA for ; Wed, 15 Nov 2023 08:30:52 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 2D04FDA7; Wed, 15 Nov 2023 08:31:38 -0800 (PST) Received: from e125769.cambridge.arm.com (e125769.cambridge.arm.com [10.1.196.26]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 72D2D3F641; Wed, 15 Nov 2023 08:30:49 -0800 (PST) From: Ryan Roberts To: Catalin Marinas , Will Deacon , Ard Biesheuvel , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Zenghui Yu , Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Andrew Morton , Anshuman Khandual , Matthew Wilcox , Yu Zhao , Mark Rutland , David Hildenbrand , Kefeng Wang , John Hubbard , Zi Yan Cc: Ryan Roberts , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 06/14] arm64/mm: ptep_test_and_clear_young(): New layer to manage contig bit Date: Wed, 15 Nov 2023 16:30:10 +0000 Message-Id: <20231115163018.1303287-7-ryan.roberts@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231115163018.1303287-1-ryan.roberts@arm.com> References: <20231115163018.1303287-1-ryan.roberts@arm.com> MIME-Version: 1.0 X-Spam-Status: No, score=-0.8 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lipwig.vger.email Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (lipwig.vger.email [0.0.0.0]); Wed, 15 Nov 2023 08:32:43 -0800 (PST) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1782648374751062719 X-GMAIL-MSGID: 1782648374751062719 Create a new layer for the in-table PTE manipulation APIs. For now, The existing API is prefixed with double underscore to become the arch-private API and the public API is just a simple wrapper that calls the private API. The public API implementation will subsequently be used to transparently manipulate the contiguous bit where appropriate. But since there are already some contig-aware users (e.g. hugetlb, kernel mapper), we must first ensure those users use the private API directly so that the future contig-bit manipulations in the public API do not interfere with those existing uses. Signed-off-by: Ryan Roberts --- arch/arm64/include/asm/pgtable.h | 18 +++++++----------- 1 file changed, 7 insertions(+), 11 deletions(-) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 994597a0bb0f..9b4a9909fd5b 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -887,8 +887,9 @@ static inline bool pud_user_accessible_page(pud_t pud) /* * Atomic pte/pmd modifications. */ -#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG -static inline int __ptep_test_and_clear_young(pte_t *ptep) +static inline int __ptep_test_and_clear_young(struct vm_area_struct *vma, + unsigned long address, + pte_t *ptep) { pte_t old_pte, pte; @@ -903,18 +904,11 @@ static inline int __ptep_test_and_clear_young(pte_t *ptep) return pte_young(pte); } -static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, - unsigned long address, - pte_t *ptep) -{ - return __ptep_test_and_clear_young(ptep); -} - #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH static inline int ptep_clear_flush_young(struct vm_area_struct *vma, unsigned long address, pte_t *ptep) { - int young = ptep_test_and_clear_young(vma, address, ptep); + int young = __ptep_test_and_clear_young(vma, address, ptep); if (young) { /* @@ -937,7 +931,7 @@ static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma, unsigned long address, pmd_t *pmdp) { - return ptep_test_and_clear_young(vma, address, (pte_t *)pmdp); + return __ptep_test_and_clear_young(vma, address, (pte_t *)pmdp); } #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ @@ -1123,6 +1117,8 @@ extern void ptep_modify_prot_commit(struct vm_area_struct *vma, #define pte_clear __pte_clear #define __HAVE_ARCH_PTEP_GET_AND_CLEAR #define ptep_get_and_clear __ptep_get_and_clear +#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG +#define ptep_test_and_clear_young __ptep_test_and_clear_young #endif /* !__ASSEMBLY__ */ From patchwork Wed Nov 15 16:30:11 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ryan Roberts X-Patchwork-Id: 165470 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b909:0:b0:403:3b70:6f57 with SMTP id t9csp2657159vqg; Wed, 15 Nov 2023 08:32:55 -0800 (PST) X-Google-Smtp-Source: AGHT+IF04bw9w9uXiMRGF8YL3C+gxvITqKTf/Hf67kqFZV2scutZokZWS9zP7++tvkJbIcVMb9gi X-Received: by 2002:a05:6a21:9988:b0:186:10d6:cc64 with SMTP id ve8-20020a056a21998800b0018610d6cc64mr11732765pzb.44.1700065975119; Wed, 15 Nov 2023 08:32:55 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1700065975; cv=none; d=google.com; s=arc-20160816; b=rlUP0egOgIvHRfxbBLbN9zrsh0l+BBrxfRauHX3nvdfkGG0WeQfV1Mbadxy5YitJA+ akqek2wG5Fr3PYyD8VmS8c3y8HMz1/iV1x5Zcac4U99x+iipg2nGc2bxwCVtmcxNLnyb sVvPy2D+26ptU7TYJ6322Ur2cOaGTGyJSBl2eSTdTemxJV5QVOuQPFbpQRoif107+z5c fQQuwqPyzdOn9nk1yVirtcWJhEHLS/wuhlToH10xkt8++X0GDp93Jc/NSPzPNAmEaxCW Xbv+P1iJI1mgyGBVjwp6wd+5cwHDEmDOdV5e3fDaSJPK8awaVzLRnYSEMy3h/dqk8Rhb tFsQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from; bh=eY6NiicJ90X6+1Q0eg6fxYOX0IQ4OXMtCPZ2hrvQ55c=; fh=CVYMMnwSLqNeTtsgqDZkAN2xp/CPaSWpO0DiPqQVZ5w=; b=UEMh1jyxPJ64+UrBRmmvc6mZyvnwtJO8cCNBfBDtZxSuXgX44oLFBGTpywi4ErOCN3 MoXlVXjk44LY/QH/F5lH2u4Yq6OQ56L+mQ+hW2Lc651hZoS3HzGy+ocOuTXu0XSL28l1 GrXNnXPPs1L+fhYMp5Shqr8+HMSMuOTN+4zH+kmQKcZo+QBJv0qaLWXQaKA5t8ABwtxC UM2uNhjTlTNsnYTdhctRMschbF4pPZqi806B/dNmCGvwg6fJqVJP/hm+cQYzN7zO00iT o2l8Lrmtoh7/jOB5hIv5Khgt081v/13vGZUfmgQzDyqnPYp7NFuufCObAbC4Cl5NYpw0 Qycw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:3 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from lipwig.vger.email (lipwig.vger.email. [2620:137:e000::3:3]) by mx.google.com with ESMTPS id fh13-20020a056a00390d00b006933e8fec67si10827415pfb.227.2023.11.15.08.32.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Nov 2023 08:32:55 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:3 as permitted sender) client-ip=2620:137:e000::3:3; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:3 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by lipwig.vger.email (Postfix) with ESMTP id 4A23E802617B; Wed, 15 Nov 2023 08:32:51 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at lipwig.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232465AbjKOQbO (ORCPT + 29 others); Wed, 15 Nov 2023 11:31:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37616 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232476AbjKOQbF (ORCPT ); Wed, 15 Nov 2023 11:31:05 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 0FAF6D5D for ; Wed, 15 Nov 2023 08:30:56 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 70C3115DB; Wed, 15 Nov 2023 08:31:41 -0800 (PST) Received: from e125769.cambridge.arm.com (e125769.cambridge.arm.com [10.1.196.26]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id B6F783F641; Wed, 15 Nov 2023 08:30:52 -0800 (PST) From: Ryan Roberts To: Catalin Marinas , Will Deacon , Ard Biesheuvel , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Zenghui Yu , Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Andrew Morton , Anshuman Khandual , Matthew Wilcox , Yu Zhao , Mark Rutland , David Hildenbrand , Kefeng Wang , John Hubbard , Zi Yan Cc: Ryan Roberts , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 07/14] arm64/mm: ptep_clear_flush_young(): New layer to manage contig bit Date: Wed, 15 Nov 2023 16:30:11 +0000 Message-Id: <20231115163018.1303287-8-ryan.roberts@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231115163018.1303287-1-ryan.roberts@arm.com> References: <20231115163018.1303287-1-ryan.roberts@arm.com> MIME-Version: 1.0 X-Spam-Status: No, score=-0.8 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lipwig.vger.email Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (lipwig.vger.email [0.0.0.0]); Wed, 15 Nov 2023 08:32:51 -0800 (PST) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1782648379656164500 X-GMAIL-MSGID: 1782648379656164500 Create a new layer for the in-table PTE manipulation APIs. For now, The existing API is prefixed with double underscore to become the arch-private API and the public API is just a simple wrapper that calls the private API. The public API implementation will subsequently be used to transparently manipulate the contiguous bit where appropriate. But since there are already some contig-aware users (e.g. hugetlb, kernel mapper), we must first ensure those users use the private API directly so that the future contig-bit manipulations in the public API do not interfere with those existing uses. Signed-off-by: Ryan Roberts --- arch/arm64/include/asm/pgtable.h | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 9b4a9909fd5b..fc1005222ee4 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -138,7 +138,7 @@ static inline pteval_t __phys_to_pte_val(phys_addr_t phys) * so that we don't erroneously return false for pages that have been * remapped as PROT_NONE but are yet to be flushed from the TLB. * Note that we can't make any assumptions based on the state of the access - * flag, since ptep_clear_flush_young() elides a DSB when invalidating the + * flag, since __ptep_clear_flush_young() elides a DSB when invalidating the * TLB. */ #define pte_accessible(mm, pte) \ @@ -904,8 +904,7 @@ static inline int __ptep_test_and_clear_young(struct vm_area_struct *vma, return pte_young(pte); } -#define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH -static inline int ptep_clear_flush_young(struct vm_area_struct *vma, +static inline int __ptep_clear_flush_young(struct vm_area_struct *vma, unsigned long address, pte_t *ptep) { int young = __ptep_test_and_clear_young(vma, address, ptep); @@ -1119,6 +1118,8 @@ extern void ptep_modify_prot_commit(struct vm_area_struct *vma, #define ptep_get_and_clear __ptep_get_and_clear #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG #define ptep_test_and_clear_young __ptep_test_and_clear_young +#define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH +#define ptep_clear_flush_young __ptep_clear_flush_young #endif /* !__ASSEMBLY__ */ From patchwork Wed Nov 15 16:30:12 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ryan Roberts X-Patchwork-Id: 165471 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b909:0:b0:403:3b70:6f57 with SMTP id t9csp2657162vqg; Wed, 15 Nov 2023 08:32:55 -0800 (PST) X-Google-Smtp-Source: AGHT+IGmr8J+ySrvzqZIrfaC2hJjzp30QQNw5kPTS3EjO4oET5iLhOG++wZCl866WmmLZAW4ucj3 X-Received: by 2002:a17:90b:4f41:b0:27d:63ae:f378 with SMTP id pj1-20020a17090b4f4100b0027d63aef378mr13957056pjb.42.1700065975438; Wed, 15 Nov 2023 08:32:55 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1700065975; cv=none; d=google.com; s=arc-20160816; b=CxkZ6vuHkdYgDWv5++4EwKoocoXEPA58E1jkbC611Wm5HaqvvXqsnYYgUbaB4407lL rSga7JrcXwWEc+4U2pkkilFgI00jHfpSrPbbzc7E+MW36KUJIcIdcK+oXmSAqggxUqdq k2Ewn0a154KNLf3rzJLxuvjaOhkaV1YoiCCBNKFde0VioW3CVlJXLEsSnB97RbwisCRr Id8XNDDV7r+C7rVZE4lsyHPLE+TSe5C7XuOrT0R6N/viK2pvJIAmQXMdeVRtQBgdQvv0 Bv9xa8vgHaVuXDgeaQRK+Kb4HFP2lgZ5sbZYUN9rAtxpBR+PCnqk/4U4DYLD50AyD/pp DxjA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from; bh=2IQirIHWGTN0C5ucPumITjyI4YT5MYNWep5+T8WG/E4=; fh=CVYMMnwSLqNeTtsgqDZkAN2xp/CPaSWpO0DiPqQVZ5w=; b=KWaY8h8/uSGBiCDyw7FOzWR2QI9Avy/5dfmtB/PvsnvtWUrKNpty079R6ZWB5iSkl6 y+SifczIYeB3q1ltgW06MdabupCu/bFC+8iqzFiGgrK/1wOUDFvNMf4WiZTVjhtiXsDY qCpbS7opkNHqe035h5l8pyk8Moc6dFtvZlQS02ShXOAKxBAJvipQpesO5lWjR+binn6P /36Z3pICALcVys5NPhMEtfQM3eitXjkjjJsBy9o/J3Kx4oXYX3lMuK9KGVwKZoxzRWAf G/onfm17JJBeU2tYgAtFdEXBT9pVCIRw1+ooY59ZrJLia23AKvY7XbpA15vGXcH00hqj 1dHg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.33 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from lipwig.vger.email (lipwig.vger.email. [23.128.96.33]) by mx.google.com with ESMTPS id a4-20020a17090a854400b00274a5edad0csi87089pjw.139.2023.11.15.08.32.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Nov 2023 08:32:55 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.33 as permitted sender) client-ip=23.128.96.33; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.33 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by lipwig.vger.email (Postfix) with ESMTP id 660D780226BE; Wed, 15 Nov 2023 08:32:51 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at lipwig.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232665AbjKOQb0 (ORCPT + 29 others); Wed, 15 Nov 2023 11:31:26 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37962 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232561AbjKOQbJ (ORCPT ); Wed, 15 Nov 2023 11:31:09 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 638851730 for ; Wed, 15 Nov 2023 08:30:59 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B3D151595; Wed, 15 Nov 2023 08:31:44 -0800 (PST) Received: from e125769.cambridge.arm.com (e125769.cambridge.arm.com [10.1.196.26]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 05EED3F641; Wed, 15 Nov 2023 08:30:55 -0800 (PST) From: Ryan Roberts To: Catalin Marinas , Will Deacon , Ard Biesheuvel , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Zenghui Yu , Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Andrew Morton , Anshuman Khandual , Matthew Wilcox , Yu Zhao , Mark Rutland , David Hildenbrand , Kefeng Wang , John Hubbard , Zi Yan Cc: Ryan Roberts , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 08/14] arm64/mm: ptep_set_wrprotect(): New layer to manage contig bit Date: Wed, 15 Nov 2023 16:30:12 +0000 Message-Id: <20231115163018.1303287-9-ryan.roberts@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231115163018.1303287-1-ryan.roberts@arm.com> References: <20231115163018.1303287-1-ryan.roberts@arm.com> MIME-Version: 1.0 X-Spam-Status: No, score=-0.8 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lipwig.vger.email Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (lipwig.vger.email [0.0.0.0]); Wed, 15 Nov 2023 08:32:51 -0800 (PST) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1782648380175226931 X-GMAIL-MSGID: 1782648380175226931 Create a new layer for the in-table PTE manipulation APIs. For now, The existing API is prefixed with double underscore to become the arch-private API and the public API is just a simple wrapper that calls the private API. The public API implementation will subsequently be used to transparently manipulate the contiguous bit where appropriate. But since there are already some contig-aware users (e.g. hugetlb, kernel mapper), we must first ensure those users use the private API directly so that the future contig-bit manipulations in the public API do not interfere with those existing uses. Signed-off-by: Ryan Roberts --- arch/arm64/include/asm/pgtable.h | 10 ++++++---- arch/arm64/mm/hugetlbpage.c | 2 +- 2 files changed, 7 insertions(+), 5 deletions(-) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index fc1005222ee4..423cc32b2777 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -958,11 +958,11 @@ static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm, #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ /* - * ptep_set_wrprotect - mark read-only while trasferring potential hardware + * __ptep_set_wrprotect - mark read-only while trasferring potential hardware * dirty status (PTE_DBM && !PTE_RDONLY) to the software PTE_DIRTY bit. */ -#define __HAVE_ARCH_PTEP_SET_WRPROTECT -static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long address, pte_t *ptep) +static inline void __ptep_set_wrprotect(struct mm_struct *mm, + unsigned long address, pte_t *ptep) { pte_t old_pte, pte; @@ -980,7 +980,7 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addres static inline void pmdp_set_wrprotect(struct mm_struct *mm, unsigned long address, pmd_t *pmdp) { - ptep_set_wrprotect(mm, address, (pte_t *)pmdp); + __ptep_set_wrprotect(mm, address, (pte_t *)pmdp); } #define pmdp_establish pmdp_establish @@ -1120,6 +1120,8 @@ extern void ptep_modify_prot_commit(struct vm_area_struct *vma, #define ptep_test_and_clear_young __ptep_test_and_clear_young #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH #define ptep_clear_flush_young __ptep_clear_flush_young +#define __HAVE_ARCH_PTEP_SET_WRPROTECT +#define ptep_set_wrprotect __ptep_set_wrprotect #endif /* !__ASSEMBLY__ */ diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c index c2a753541d13..952462820d9d 100644 --- a/arch/arm64/mm/hugetlbpage.c +++ b/arch/arm64/mm/hugetlbpage.c @@ -493,7 +493,7 @@ void huge_ptep_set_wrprotect(struct mm_struct *mm, pte_t pte; if (!pte_cont(READ_ONCE(*ptep))) { - ptep_set_wrprotect(mm, addr, ptep); + __ptep_set_wrprotect(mm, addr, ptep); return; } From patchwork Wed Nov 15 16:30:13 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ryan Roberts X-Patchwork-Id: 165476 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b909:0:b0:403:3b70:6f57 with SMTP id t9csp2657453vqg; Wed, 15 Nov 2023 08:33:24 -0800 (PST) X-Google-Smtp-Source: AGHT+IGf1d8GaJCp+iDBtfaTjTAwxNrsksVjY5SRO0XfG0NuB/u4phZ708QBrX/TscSSzj0PNaoM X-Received: by 2002:a05:6a20:7486:b0:15e:dc75:66a7 with SMTP id p6-20020a056a20748600b0015edc7566a7mr11576725pzd.24.1700066004432; Wed, 15 Nov 2023 08:33:24 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1700066004; cv=none; d=google.com; s=arc-20160816; b=LDKB8mm6cRAS2rlS4YxjK5XSYReA2gCZSWeK24feXHrmxoDRMrs9NRRGNXio6PCe6B MU6L4YkQJmQW250nIWAagTl6pV8ANW/5xuKUHJH2LiBtG9QdDz1D9pQ5UCcAreCTHHFg 3w/vDiAx3CJhwuzhB+LCchJtGxz5x6yc3CPSkRX4uGFKUTzIeggMxxYVgxZGZLBOCqpl a0k1LWxhyWsFuwHT72+KoS+XjSr8DBvZXopl4yDeXsRHrtMRG8PcSgrj94B8MqzFTV+b IxL7N7l571Dy0o/BX6i2u94d6+MK9e8JSHfd04UPVMOTtQ+eBJbk4R9mtyZ/3VSOEslZ +VTg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from; bh=H0BwGCXMY0Jm/jIsiVmBBtVJvXghyud81fHEkKj7GCo=; fh=CVYMMnwSLqNeTtsgqDZkAN2xp/CPaSWpO0DiPqQVZ5w=; b=xxRCn7xvnVVs8xAQlrQTiFK8jU03ZxPb0xRZTApG6FG9pUpQSJ9ECuzMjz+CYbs2V/ w64Y85Rw6fppfkRYcrU8dYrd6Tfn2TqvoGoO7/n3JuAxMlHFcZaWKfzz6aWTP7SJB7QE Lryo+/bJdOgiV96GlvdcfG50FKVk3QRtZUCX6IBoePz1GrDVQPr7IZVnAHldBjYhxa6H L5PiFQ/DhUUpMKMgLRjm8mBE8OzRSNnbVBSeHv4c8bFbFJobDakORCykZrUUs9EUtc8q A/RqM2K5zgbnEFAvvaOBCPSuMu4qjC2AFHmKNFcChRCPDt4m5c80I+eVESceVZOvDLzG xK3A== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.37 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from snail.vger.email (snail.vger.email. [23.128.96.37]) by mx.google.com with ESMTPS id e2-20020a635442000000b005bd39be60b3si9864375pgm.390.2023.11.15.08.33.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Nov 2023 08:33:24 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.37 as permitted sender) client-ip=23.128.96.37; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.37 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by snail.vger.email (Postfix) with ESMTP id 7048281444D8; Wed, 15 Nov 2023 08:31:40 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at snail.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232739AbjKOQbf (ORCPT + 29 others); Wed, 15 Nov 2023 11:31:35 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38598 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232740AbjKOQbV (ORCPT ); Wed, 15 Nov 2023 11:31:21 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id C48C819D for ; Wed, 15 Nov 2023 08:31:02 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 02C4DDA7; Wed, 15 Nov 2023 08:31:48 -0800 (PST) Received: from e125769.cambridge.arm.com (e125769.cambridge.arm.com [10.1.196.26]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 48AB23F641; Wed, 15 Nov 2023 08:30:59 -0800 (PST) From: Ryan Roberts To: Catalin Marinas , Will Deacon , Ard Biesheuvel , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Zenghui Yu , Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Andrew Morton , Anshuman Khandual , Matthew Wilcox , Yu Zhao , Mark Rutland , David Hildenbrand , Kefeng Wang , John Hubbard , Zi Yan Cc: Ryan Roberts , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 09/14] arm64/mm: ptep_set_access_flags(): New layer to manage contig bit Date: Wed, 15 Nov 2023 16:30:13 +0000 Message-Id: <20231115163018.1303287-10-ryan.roberts@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231115163018.1303287-1-ryan.roberts@arm.com> References: <20231115163018.1303287-1-ryan.roberts@arm.com> MIME-Version: 1.0 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_BLOCKED,SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (snail.vger.email [0.0.0.0]); Wed, 15 Nov 2023 08:31:40 -0800 (PST) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1782648410530445153 X-GMAIL-MSGID: 1782648410530445153 Create a new layer for the in-table PTE manipulation APIs. For now, The existing API is prefixed with double underscore to become the arch-private API and the public API is just a simple wrapper that calls the private API. The public API implementation will subsequently be used to transparently manipulate the contiguous bit where appropriate. But since there are already some contig-aware users (e.g. hugetlb, kernel mapper), we must first ensure those users use the private API directly so that the future contig-bit manipulations in the public API do not interfere with those existing uses. Signed-off-by: Ryan Roberts --- arch/arm64/include/asm/pgtable.h | 10 ++++++---- arch/arm64/mm/fault.c | 6 +++--- arch/arm64/mm/hugetlbpage.c | 2 +- 3 files changed, 10 insertions(+), 8 deletions(-) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 423cc32b2777..85010c2d4dfa 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -312,7 +312,7 @@ static inline void __check_safe_pte_update(struct mm_struct *mm, pte_t *ptep, /* * Check for potential race with hardware updates of the pte - * (ptep_set_access_flags safely changes valid ptes without going + * (__ptep_set_access_flags safely changes valid ptes without going * through an invalid entry). */ VM_WARN_ONCE(!pte_young(pte), @@ -842,8 +842,7 @@ static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot) return pte_pmd(pte_modify(pmd_pte(pmd), newprot)); } -#define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS -extern int ptep_set_access_flags(struct vm_area_struct *vma, +extern int __ptep_set_access_flags(struct vm_area_struct *vma, unsigned long address, pte_t *ptep, pte_t entry, int dirty); @@ -853,7 +852,8 @@ static inline int pmdp_set_access_flags(struct vm_area_struct *vma, unsigned long address, pmd_t *pmdp, pmd_t entry, int dirty) { - return ptep_set_access_flags(vma, address, (pte_t *)pmdp, pmd_pte(entry), dirty); + return __ptep_set_access_flags(vma, address, (pte_t *)pmdp, + pmd_pte(entry), dirty); } static inline int pud_devmap(pud_t pud) @@ -1122,6 +1122,8 @@ extern void ptep_modify_prot_commit(struct vm_area_struct *vma, #define ptep_clear_flush_young __ptep_clear_flush_young #define __HAVE_ARCH_PTEP_SET_WRPROTECT #define ptep_set_wrprotect __ptep_set_wrprotect +#define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS +#define ptep_set_access_flags __ptep_set_access_flags #endif /* !__ASSEMBLY__ */ diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index a287c1dea871..7cebd9847aae 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -209,9 +209,9 @@ static void show_pte(unsigned long addr) * * Returns whether or not the PTE actually changed. */ -int ptep_set_access_flags(struct vm_area_struct *vma, - unsigned long address, pte_t *ptep, - pte_t entry, int dirty) +int __ptep_set_access_flags(struct vm_area_struct *vma, + unsigned long address, pte_t *ptep, + pte_t entry, int dirty) { pteval_t old_pteval, pteval; pte_t pte = READ_ONCE(*ptep); diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c index 952462820d9d..627a9717e98c 100644 --- a/arch/arm64/mm/hugetlbpage.c +++ b/arch/arm64/mm/hugetlbpage.c @@ -459,7 +459,7 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma, pte_t orig_pte; if (!pte_cont(pte)) - return ptep_set_access_flags(vma, addr, ptep, pte, dirty); + return __ptep_set_access_flags(vma, addr, ptep, pte, dirty); ncontig = find_num_contig(mm, addr, ptep, &pgsize); dpfn = pgsize >> PAGE_SHIFT; From patchwork Wed Nov 15 16:30:14 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ryan Roberts X-Patchwork-Id: 165477 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b909:0:b0:403:3b70:6f57 with SMTP id t9csp2657598vqg; Wed, 15 Nov 2023 08:33:36 -0800 (PST) X-Google-Smtp-Source: AGHT+IFb+481S+25+Xhvi6D9edXVlDizQIY2BREZIIAZvMPNYHjK3zdEuNscHdIBNCCRhCWj2rMg X-Received: by 2002:a17:902:db07:b0:1cc:5dd4:7ce5 with SMTP id m7-20020a170902db0700b001cc5dd47ce5mr7761581plx.19.1700066016398; Wed, 15 Nov 2023 08:33:36 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1700066016; cv=none; d=google.com; s=arc-20160816; b=vfv6+1zDFIjSEIOwsFsxW7qi6zhitSUD0ZBElIgKgKCAE61NinSZZkb+XG9tA+sjGq gbR30EPJXhCwrSQjtLnVks2g31T7u+Uh50mUjBUna6pP7zMJ9NL8wNx7N+myH0jZn11t AB+SA6eDvmcq30TWXJWGxqE/xJ1jqa6xGI0uii7q6W7njzlRxXVRwFIo3TXevvmDEAvR ANeB7IT4MU3ek4NQkSGP0NdxW4qI9S6YWq9whqnNvB7xyFiP18nURuhxON3Hx4hDV5yI KA4jW0IT1zsKXSzlTnldR2v2v9QqT7UTKoLEpVFW7SZokAIjlFbqAfHCBxXCz5647cd7 9law== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from; bh=/VxtEV8E64tqDjSTd4uv2FQfTUg5XNfrhh1313bOMIY=; fh=CVYMMnwSLqNeTtsgqDZkAN2xp/CPaSWpO0DiPqQVZ5w=; b=xbK0FPW9omFhPxBW3Fx/xgoaDixsVkMScTUhEmpOZiQ6JaUFcGEV5kwXW1hqU4uw+T VHiAgy5c/0QyyWOARGevwL3GgkYhwSvEhYjslKQGI8pOQCSyUGAMmuQFmxSpPG6v4P5w 5oy8VL3rYo+OluipnCgSM1l0VqzNf3mBzi45O6jKltSYZXE+UWHh0BeOXQLlvHzj0128 kNegJCC9z+xPmagyeQRB03O/aaJxMoQyihFRosJOV8upHxCLZZPGsrRLOgX3yljyyTza a+0FXfNUNUPqZvAmBLIQxP6S7k93k9nzkVVS0TqiRuqmahte4ULRxZwpGkcQatOMkgoY OObw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from snail.vger.email (snail.vger.email. [2620:137:e000::3:7]) by mx.google.com with ESMTPS id d24-20020a170902b71800b001cc6101208asi10063325pls.569.2023.11.15.08.33.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Nov 2023 08:33:36 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) client-ip=2620:137:e000::3:7; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by snail.vger.email (Postfix) with ESMTP id 481288212AAE; Wed, 15 Nov 2023 08:32:07 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at snail.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232781AbjKOQbl (ORCPT + 29 others); Wed, 15 Nov 2023 11:31:41 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37728 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232774AbjKOQbX (ORCPT ); Wed, 15 Nov 2023 11:31:23 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 10A5898 for ; Wed, 15 Nov 2023 08:31:06 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 46B5A15DB; Wed, 15 Nov 2023 08:31:51 -0800 (PST) Received: from e125769.cambridge.arm.com (e125769.cambridge.arm.com [10.1.196.26]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8C2583F641; Wed, 15 Nov 2023 08:31:02 -0800 (PST) From: Ryan Roberts To: Catalin Marinas , Will Deacon , Ard Biesheuvel , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Zenghui Yu , Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Andrew Morton , Anshuman Khandual , Matthew Wilcox , Yu Zhao , Mark Rutland , David Hildenbrand , Kefeng Wang , John Hubbard , Zi Yan Cc: Ryan Roberts , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 10/14] arm64/mm: ptep_get(): New layer to manage contig bit Date: Wed, 15 Nov 2023 16:30:14 +0000 Message-Id: <20231115163018.1303287-11-ryan.roberts@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231115163018.1303287-1-ryan.roberts@arm.com> References: <20231115163018.1303287-1-ryan.roberts@arm.com> MIME-Version: 1.0 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_BLOCKED,SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (snail.vger.email [0.0.0.0]); Wed, 15 Nov 2023 08:32:07 -0800 (PST) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1782648423191970519 X-GMAIL-MSGID: 1782648423191970519 Create a new layer for the in-table PTE manipulation APIs. For now, The existing API is prefixed with double underscore to become the arch-private API and the public API is just a simple wrapper that calls the private API. The public API implementation will subsequently be used to transparently manipulate the contiguous bit where appropriate. But since there are already some contig-aware users (e.g. hugetlb, kernel mapper), we must first ensure those users use the private API directly so that the future contig-bit manipulations in the public API do not interfere with those existing uses. arm64 did not previously define an arch-specific ptep_get(), so override the default version in the arch code, and also define the private __ptep_get() version. Currently they both do the same thing that the default version does (READ_ONCE()). Some arch users (hugetlb) were already using ptep_get() so convert those to the private API. While other callsites were doing direct READ_ONCE(), so convert those to use the appropriate (public/private) API too. Signed-off-by: Ryan Roberts --- arch/arm64/include/asm/pgtable.h | 12 +++++++++--- arch/arm64/kernel/efi.c | 2 +- arch/arm64/mm/fault.c | 4 ++-- arch/arm64/mm/hugetlbpage.c | 18 +++++++++--------- arch/arm64/mm/kasan_init.c | 2 +- arch/arm64/mm/mmu.c | 12 ++++++------ arch/arm64/mm/pageattr.c | 4 ++-- arch/arm64/mm/trans_pgd.c | 2 +- 8 files changed, 31 insertions(+), 25 deletions(-) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 85010c2d4dfa..6930c14f062f 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -276,6 +276,11 @@ static inline void __set_pte(pte_t *ptep, pte_t pte) } } +static inline pte_t __ptep_get(pte_t *ptep) +{ + return READ_ONCE(*ptep); +} + extern void __sync_icache_dcache(pte_t pteval); bool pgattr_change_is_safe(u64 old, u64 new); @@ -303,7 +308,7 @@ static inline void __check_safe_pte_update(struct mm_struct *mm, pte_t *ptep, if (!IS_ENABLED(CONFIG_DEBUG_VM)) return; - old_pte = READ_ONCE(*ptep); + old_pte = __ptep_get(ptep); if (!pte_valid(old_pte) || !pte_valid(pte)) return; @@ -893,7 +898,7 @@ static inline int __ptep_test_and_clear_young(struct vm_area_struct *vma, { pte_t old_pte, pte; - pte = READ_ONCE(*ptep); + pte = __ptep_get(ptep); do { old_pte = pte; pte = pte_mkold(pte); @@ -966,7 +971,7 @@ static inline void __ptep_set_wrprotect(struct mm_struct *mm, { pte_t old_pte, pte; - pte = READ_ONCE(*ptep); + pte = __ptep_get(ptep); do { old_pte = pte; pte = pte_wrprotect(pte); @@ -1111,6 +1116,7 @@ extern void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep, pte_t old_pte, pte_t new_pte); +#define ptep_get __ptep_get #define set_pte __set_pte #define set_ptes __set_ptes #define pte_clear __pte_clear diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c index 44288a12fc6c..9afcc690fe73 100644 --- a/arch/arm64/kernel/efi.c +++ b/arch/arm64/kernel/efi.c @@ -103,7 +103,7 @@ static int __init set_permissions(pte_t *ptep, unsigned long addr, void *data) { struct set_perm_data *spd = data; const efi_memory_desc_t *md = spd->md; - pte_t pte = READ_ONCE(*ptep); + pte_t pte = __ptep_get(ptep); if (md->attribute & EFI_MEMORY_RO) pte = set_pte_bit(pte, __pgprot(PTE_RDONLY)); diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index 7cebd9847aae..d63f3a0a7251 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -191,7 +191,7 @@ static void show_pte(unsigned long addr) if (!ptep) break; - pte = READ_ONCE(*ptep); + pte = __ptep_get(ptep); pr_cont(", pte=%016llx", pte_val(pte)); pte_unmap(ptep); } while(0); @@ -214,7 +214,7 @@ int __ptep_set_access_flags(struct vm_area_struct *vma, pte_t entry, int dirty) { pteval_t old_pteval, pteval; - pte_t pte = READ_ONCE(*ptep); + pte_t pte = __ptep_get(ptep); if (pte_same(pte, entry)) return 0; diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c index 627a9717e98c..52fb767607e0 100644 --- a/arch/arm64/mm/hugetlbpage.c +++ b/arch/arm64/mm/hugetlbpage.c @@ -152,14 +152,14 @@ pte_t huge_ptep_get(pte_t *ptep) { int ncontig, i; size_t pgsize; - pte_t orig_pte = ptep_get(ptep); + pte_t orig_pte = __ptep_get(ptep); if (!pte_present(orig_pte) || !pte_cont(orig_pte)) return orig_pte; ncontig = num_contig_ptes(page_size(pte_page(orig_pte)), &pgsize); for (i = 0; i < ncontig; i++, ptep++) { - pte_t pte = ptep_get(ptep); + pte_t pte = __ptep_get(ptep); if (pte_dirty(pte)) orig_pte = pte_mkdirty(orig_pte); @@ -184,7 +184,7 @@ static pte_t get_clear_contig(struct mm_struct *mm, unsigned long pgsize, unsigned long ncontig) { - pte_t orig_pte = ptep_get(ptep); + pte_t orig_pte = __ptep_get(ptep); unsigned long i; for (i = 0; i < ncontig; i++, addr += pgsize, ptep++) { @@ -408,7 +408,7 @@ pte_t huge_ptep_get_and_clear(struct mm_struct *mm, { int ncontig; size_t pgsize; - pte_t orig_pte = ptep_get(ptep); + pte_t orig_pte = __ptep_get(ptep); if (!pte_cont(orig_pte)) return __ptep_get_and_clear(mm, addr, ptep); @@ -431,11 +431,11 @@ static int __cont_access_flags_changed(pte_t *ptep, pte_t pte, int ncontig) { int i; - if (pte_write(pte) != pte_write(ptep_get(ptep))) + if (pte_write(pte) != pte_write(__ptep_get(ptep))) return 1; for (i = 0; i < ncontig; i++) { - pte_t orig_pte = ptep_get(ptep + i); + pte_t orig_pte = __ptep_get(ptep + i); if (pte_dirty(pte) != pte_dirty(orig_pte)) return 1; @@ -492,7 +492,7 @@ void huge_ptep_set_wrprotect(struct mm_struct *mm, size_t pgsize; pte_t pte; - if (!pte_cont(READ_ONCE(*ptep))) { + if (!pte_cont(__ptep_get(ptep))) { __ptep_set_wrprotect(mm, addr, ptep); return; } @@ -517,7 +517,7 @@ pte_t huge_ptep_clear_flush(struct vm_area_struct *vma, size_t pgsize; int ncontig; - if (!pte_cont(READ_ONCE(*ptep))) + if (!pte_cont(__ptep_get(ptep))) return ptep_clear_flush(vma, addr, ptep); ncontig = find_num_contig(mm, addr, ptep, &pgsize); @@ -550,7 +550,7 @@ pte_t huge_ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr * when the permission changes from executable to non-executable * in cases where cpu is affected with errata #2645198. */ - if (pte_user_exec(READ_ONCE(*ptep))) + if (pte_user_exec(__ptep_get(ptep))) return huge_ptep_clear_flush(vma, addr, ptep); } return huge_ptep_get_and_clear(vma->vm_mm, addr, ptep); diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c index 5eade712e9e5..5274c317d775 100644 --- a/arch/arm64/mm/kasan_init.c +++ b/arch/arm64/mm/kasan_init.c @@ -113,7 +113,7 @@ static void __init kasan_pte_populate(pmd_t *pmdp, unsigned long addr, memset(__va(page_phys), KASAN_SHADOW_INIT, PAGE_SIZE); next = addr + PAGE_SIZE; __set_pte(ptep, pfn_pte(__phys_to_pfn(page_phys), PAGE_KERNEL)); - } while (ptep++, addr = next, addr != end && pte_none(READ_ONCE(*ptep))); + } while (ptep++, addr = next, addr != end && pte_none(__ptep_get(ptep))); } static void __init kasan_pmd_populate(pud_t *pudp, unsigned long addr, diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 080e9b50f595..784f1e312447 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -176,7 +176,7 @@ static void init_pte(pmd_t *pmdp, unsigned long addr, unsigned long end, ptep = pte_set_fixmap_offset(pmdp, addr); do { - pte_t old_pte = READ_ONCE(*ptep); + pte_t old_pte = __ptep_get(ptep); __set_pte(ptep, pfn_pte(__phys_to_pfn(phys), prot)); @@ -185,7 +185,7 @@ static void init_pte(pmd_t *pmdp, unsigned long addr, unsigned long end, * only allow updates to the permission attributes. */ BUG_ON(!pgattr_change_is_safe(pte_val(old_pte), - READ_ONCE(pte_val(*ptep)))); + pte_val(__ptep_get(ptep)))); phys += PAGE_SIZE; } while (ptep++, addr += PAGE_SIZE, addr != end); @@ -854,7 +854,7 @@ static void unmap_hotplug_pte_range(pmd_t *pmdp, unsigned long addr, do { ptep = pte_offset_kernel(pmdp, addr); - pte = READ_ONCE(*ptep); + pte = __ptep_get(ptep); if (pte_none(pte)) continue; @@ -987,7 +987,7 @@ static void free_empty_pte_table(pmd_t *pmdp, unsigned long addr, do { ptep = pte_offset_kernel(pmdp, addr); - pte = READ_ONCE(*ptep); + pte = __ptep_get(ptep); /* * This is just a sanity check here which verifies that @@ -1006,7 +1006,7 @@ static void free_empty_pte_table(pmd_t *pmdp, unsigned long addr, */ ptep = pte_offset_kernel(pmdp, 0UL); for (i = 0; i < PTRS_PER_PTE; i++) { - if (!pte_none(READ_ONCE(ptep[i]))) + if (!pte_none(__ptep_get(&ptep[i]))) return; } @@ -1475,7 +1475,7 @@ pte_t ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr, pte * when the permission changes from executable to non-executable * in cases where cpu is affected with errata #2645198. */ - if (pte_user_exec(READ_ONCE(*ptep))) + if (pte_user_exec(ptep_get(ptep))) return ptep_clear_flush(vma, addr, ptep); } return ptep_get_and_clear(vma->vm_mm, addr, ptep); diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c index 057097acf9e0..624b0b0982e3 100644 --- a/arch/arm64/mm/pageattr.c +++ b/arch/arm64/mm/pageattr.c @@ -36,7 +36,7 @@ bool can_set_direct_map(void) static int change_page_range(pte_t *ptep, unsigned long addr, void *data) { struct page_change_data *cdata = data; - pte_t pte = READ_ONCE(*ptep); + pte_t pte = __ptep_get(ptep); pte = clear_pte_bit(pte, cdata->clear_mask); pte = set_pte_bit(pte, cdata->set_mask); @@ -246,5 +246,5 @@ bool kernel_page_present(struct page *page) return true; ptep = pte_offset_kernel(pmdp, addr); - return pte_valid(READ_ONCE(*ptep)); + return pte_valid(__ptep_get(ptep)); } diff --git a/arch/arm64/mm/trans_pgd.c b/arch/arm64/mm/trans_pgd.c index 230b607cf881..5139a28130c0 100644 --- a/arch/arm64/mm/trans_pgd.c +++ b/arch/arm64/mm/trans_pgd.c @@ -33,7 +33,7 @@ static void *trans_alloc(struct trans_pgd_info *info) static void _copy_pte(pte_t *dst_ptep, pte_t *src_ptep, unsigned long addr) { - pte_t pte = READ_ONCE(*src_ptep); + pte_t pte = __ptep_get(src_ptep); if (pte_valid(pte)) { /* From patchwork Wed Nov 15 16:30:15 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ryan Roberts X-Patchwork-Id: 165480 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b909:0:b0:403:3b70:6f57 with SMTP id t9csp2657915vqg; Wed, 15 Nov 2023 08:34:04 -0800 (PST) X-Google-Smtp-Source: AGHT+IE0wGFznb1Bj7GWElVrqkFJpkQFDwhTwcRM3fUN5uzl9UqbrdcrlrL+ir5n+aLfnYGQTjmk X-Received: by 2002:a05:6a00:8c02:b0:6be:acc:8973 with SMTP id ih2-20020a056a008c0200b006be0acc8973mr12662645pfb.20.1700066044336; 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[23.128.96.35]) by mx.google.com with ESMTPS id d17-20020a056a00245100b006b8e367ed42si10810242pfj.54.2023.11.15.08.34.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Nov 2023 08:34:04 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.35 as permitted sender) client-ip=23.128.96.35; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.35 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by groat.vger.email (Postfix) with ESMTP id 5AAD4805FD6B; Wed, 15 Nov 2023 08:33:58 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at groat.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232647AbjKOQbt (ORCPT + 29 others); Wed, 15 Nov 2023 11:31:49 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37972 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232807AbjKOQbZ (ORCPT ); Wed, 15 Nov 2023 11:31:25 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 58C8419B0 for ; Wed, 15 Nov 2023 08:31:09 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 88BC9DA7; Wed, 15 Nov 2023 08:31:54 -0800 (PST) Received: from e125769.cambridge.arm.com (e125769.cambridge.arm.com [10.1.196.26]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id CF1963F641; Wed, 15 Nov 2023 08:31:05 -0800 (PST) From: Ryan Roberts To: Catalin Marinas , Will Deacon , Ard Biesheuvel , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Zenghui Yu , Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Andrew Morton , Anshuman Khandual , Matthew Wilcox , Yu Zhao , Mark Rutland , David Hildenbrand , Kefeng Wang , John Hubbard , Zi Yan Cc: Ryan Roberts , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 11/14] arm64/mm: Split __flush_tlb_range() to elide trailing DSB Date: Wed, 15 Nov 2023 16:30:15 +0000 Message-Id: <20231115163018.1303287-12-ryan.roberts@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231115163018.1303287-1-ryan.roberts@arm.com> References: <20231115163018.1303287-1-ryan.roberts@arm.com> MIME-Version: 1.0 X-Spam-Status: No, score=-0.8 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on groat.vger.email Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (groat.vger.email [0.0.0.0]); Wed, 15 Nov 2023 08:33:58 -0800 (PST) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1782648452366252515 X-GMAIL-MSGID: 1782648452366252515 Split __flush_tlb_range() into __flush_tlb_range_nosync() + __flush_tlb_range(), in the same way as the existing flush_tlb_page() arrangement. This allows calling __flush_tlb_range_nosync() to elide the trailing DSB. Forthcoming "contpte" code will take advantage of this when clearing the young bit from a contiguous range of ptes. Signed-off-by: Ryan Roberts --- arch/arm64/include/asm/tlbflush.h | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/arch/arm64/include/asm/tlbflush.h b/arch/arm64/include/asm/tlbflush.h index bb2c2833a987..925ef3bdf9ed 100644 --- a/arch/arm64/include/asm/tlbflush.h +++ b/arch/arm64/include/asm/tlbflush.h @@ -399,7 +399,7 @@ do { \ #define __flush_s2_tlb_range_op(op, start, pages, stride, tlb_level) \ __flush_tlb_range_op(op, start, pages, stride, 0, tlb_level, false) -static inline void __flush_tlb_range(struct vm_area_struct *vma, +static inline void __flush_tlb_range_nosync(struct vm_area_struct *vma, unsigned long start, unsigned long end, unsigned long stride, bool last_level, int tlb_level) @@ -431,10 +431,19 @@ static inline void __flush_tlb_range(struct vm_area_struct *vma, else __flush_tlb_range_op(vae1is, start, pages, stride, asid, tlb_level, true); - dsb(ish); mmu_notifier_arch_invalidate_secondary_tlbs(vma->vm_mm, start, end); } +static inline void __flush_tlb_range(struct vm_area_struct *vma, + unsigned long start, unsigned long end, + unsigned long stride, bool last_level, + int tlb_level) +{ + __flush_tlb_range_nosync(vma, start, end, stride, + last_level, tlb_level); + dsb(ish); +} + static inline void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end) { From patchwork Wed Nov 15 16:30:16 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ryan Roberts X-Patchwork-Id: 165479 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b909:0:b0:403:3b70:6f57 with SMTP id t9csp2657652vqg; Wed, 15 Nov 2023 08:33:41 -0800 (PST) X-Google-Smtp-Source: AGHT+IFs2RRARq0v6sZd8hSbc3tbIZML5KAGHmmaJGGhcP58OEjrTlDwrJnr1A1U5IyL2Q/qxDxg X-Received: by 2002:a05:6a21:1f05:b0:180:d33d:9256 with SMTP id ry5-20020a056a211f0500b00180d33d9256mr9671693pzb.58.1700066021558; Wed, 15 Nov 2023 08:33:41 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1700066021; cv=none; d=google.com; s=arc-20160816; b=WWsFJDcidEpz6sqFASUv/BD/Jvjo2UScQ/Wla45kvGZeAb6ozIAtg9YiHOmkPSWuvJ LFjB9LFboriDWwOJDosJWtddL+L9obnUNwmrWzfbiuSNS6I2WXTheRQgjkMZamzAiQc/ vFVTxQEwNaX1unMcPHhNBJDQ8HmMW574QxZySE3FSB8uUgq+BPEsDNNgdEmkN2U4BeJR 5xSGIUcsdUeFtzWnUAcQfmMsFWUoq8jw85Z8W7XaqFd7UKjhcBfn/bMFz1eTWjyt4jma mxaUZCXgX1NaOxlLTrvMLi8d85BPzJjYxJHSKU0ktKuDDlnOBvVls8iiX4U7JZOT0y/C dU0g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from; bh=lCThfSyxcur1NkX+DVvNdNU1p/7yWg6Uho5SoX3w+rY=; fh=CVYMMnwSLqNeTtsgqDZkAN2xp/CPaSWpO0DiPqQVZ5w=; b=azl2pKdqKBvea+jDL+qRI8iwt0nCR2EaoXAyWvoPh5zEBLq051p4TU2opzHvtgFSMJ 7laEubT7P/W+5xEKqFAUriT84pOFckLfU0QSA1BB+vH3GIYpHon85qgWDYpzlczZFS37 RcY+HKnF22V6Zf3Httqf4N25+ZUncxiG08l/rjwrgNiW8vid9WLEhhc6GByx7NOPDpXX TQptULQY45ExYZ5lIoUX+ApzjMIngj/bmZNaIBlxGIszvG4SoTw2Qacjxj7Zygz0hvLy STiOzI/9jp4oKZw/TrlDyCnN0O3BkRL8t895KFlZJIAWaW7gGVV+51tx+La/GcweZUQf sDPw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from snail.vger.email (snail.vger.email. [2620:137:e000::3:7]) by mx.google.com with ESMTPS id i186-20020a639dc3000000b0058afac51c12si10914659pgd.545.2023.11.15.08.33.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Nov 2023 08:33:41 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) client-ip=2620:137:e000::3:7; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by snail.vger.email (Postfix) with ESMTP id 62BBD8212AB1; Wed, 15 Nov 2023 08:32:14 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at snail.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232609AbjKOQcA (ORCPT + 29 others); Wed, 15 Nov 2023 11:32:00 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38598 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232707AbjKOQbd (ORCPT ); Wed, 15 Nov 2023 11:31:33 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id AA3D71BD1 for ; Wed, 15 Nov 2023 08:31:12 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id E6ED91595; Wed, 15 Nov 2023 08:31:57 -0800 (PST) Received: from e125769.cambridge.arm.com (e125769.cambridge.arm.com [10.1.196.26]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 1E9903F641; Wed, 15 Nov 2023 08:31:09 -0800 (PST) From: Ryan Roberts To: Catalin Marinas , Will Deacon , Ard Biesheuvel , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Zenghui Yu , Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Andrew Morton , Anshuman Khandual , Matthew Wilcox , Yu Zhao , Mark Rutland , David Hildenbrand , Kefeng Wang , John Hubbard , Zi Yan Cc: Ryan Roberts , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 12/14] arm64/mm: Wire up PTE_CONT for user mappings Date: Wed, 15 Nov 2023 16:30:16 +0000 Message-Id: <20231115163018.1303287-13-ryan.roberts@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231115163018.1303287-1-ryan.roberts@arm.com> References: <20231115163018.1303287-1-ryan.roberts@arm.com> MIME-Version: 1.0 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_BLOCKED,SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (snail.vger.email [0.0.0.0]); Wed, 15 Nov 2023 08:32:14 -0800 (PST) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1782648428770109706 X-GMAIL-MSGID: 1782648428770109706 With the ptep API sufficiently refactored, we can now introduce a new "contpte" API layer, which transparently manages the PTE_CONT bit for user mappings. Whenever it detects a set of PTEs that meet the requirements for a contiguous range, the PTEs are re-painted with the PTE_CONT bit. Use of contpte mappings is intended to be transparent to the core-mm, which continues to interact with individual ptes. Since a contpte block only has a single access and dirty bit, the semantic here changes slightly; when getting a pte (e.g. ptep_get()) that is part of a contpte mapping, the access and dirty information are pulled from the block (so all ptes in the block return the same access/dirty info). When changing the access/dirty info on a pte (e.g. ptep_set_access_flags()) that is part of a contpte mapping, this change will affect the whole contpte block. This is works fine in practice since we guarrantee that only a single folio is mapped by a contpte block, and the core-mm tracks access/dirty information per folio. This initial change provides a baseline that can be optimized in future commits. That said, fold/unfold operations (which imply tlb invalidation) are avoided where possible with a few tricks for access/dirty bit management. Write-protect modifications for contpte mappings are currently non-optimal, and incure a regression in fork() performance. This will be addressed in follow-up changes. In order for the public functions, which used to be pure inline, to continue to be callable by modules, export all the contpte_* symbols that are now called by those public inline functions. The feature is enabled/disabled with the ARM64_CONTPTE Kconfig parameter at build time. It defaults to enabled as long as its dependency, TRANSPARENT_HUGEPAGE is also enabled. The core-mm depends upon TRANSPARENT_HUGEPAGE to be able to allocate large folios, so if its not enabled, then there is no chance of meeting the physical contiguity requirement for contpte mappings. Signed-off-by: Ryan Roberts --- arch/arm64/Kconfig | 10 +- arch/arm64/include/asm/pgtable.h | 202 ++++++++++++++++++ arch/arm64/mm/Makefile | 1 + arch/arm64/mm/contpte.c | 351 +++++++++++++++++++++++++++++++ 4 files changed, 563 insertions(+), 1 deletion(-) create mode 100644 arch/arm64/mm/contpte.c diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 7b071a00425d..de76e484ff3a 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -2209,6 +2209,15 @@ config UNWIND_PATCH_PAC_INTO_SCS select UNWIND_TABLES select DYNAMIC_SCS +config ARM64_CONTPTE + bool "Contiguous PTE mappings for user memory" if EXPERT + depends on TRANSPARENT_HUGEPAGE + default y + help + When enabled, user mappings are configured using the PTE contiguous + bit, for any mappings that meet the size and alignment requirements. + This reduces TLB pressure and improves performance. + endmenu # "Kernel Features" menu "Boot options" @@ -2318,4 +2327,3 @@ endmenu # "CPU Power Management" source "drivers/acpi/Kconfig" source "arch/arm64/kvm/Kconfig" - diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 6930c14f062f..15bc9cf1eef4 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -133,6 +133,10 @@ static inline pteval_t __phys_to_pte_val(phys_addr_t phys) */ #define pte_valid_not_user(pte) \ ((pte_val(pte) & (PTE_VALID | PTE_USER | PTE_UXN)) == (PTE_VALID | PTE_UXN)) +/* + * Returns true if the pte is valid and has the contiguous bit set. + */ +#define pte_valid_cont(pte) (pte_valid(pte) && pte_cont(pte)) /* * Could the pte be present in the TLB? We must check mm_tlb_flush_pending * so that we don't erroneously return false for pages that have been @@ -1116,6 +1120,202 @@ extern void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep, pte_t old_pte, pte_t new_pte); +#ifdef CONFIG_ARM64_CONTPTE + +/* + * The contpte APIs are used to transparently manage the contiguous bit in ptes + * where it is possible and makes sense to do so. The PTE_CONT bit is considered + * a private implementation detail of the public ptep API (see below). + */ +extern void __contpte_try_fold(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, pte_t pte); +extern void __contpte_try_unfold(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, pte_t pte); +extern pte_t contpte_ptep_get(pte_t *ptep, pte_t orig_pte); +extern pte_t contpte_ptep_get_lockless(pte_t *orig_ptep); +extern void contpte_set_ptes(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, pte_t pte, unsigned int nr); +extern int contpte_ptep_test_and_clear_young(struct vm_area_struct *vma, + unsigned long addr, pte_t *ptep); +extern int contpte_ptep_clear_flush_young(struct vm_area_struct *vma, + unsigned long addr, pte_t *ptep); +extern int contpte_ptep_set_access_flags(struct vm_area_struct *vma, + unsigned long addr, pte_t *ptep, + pte_t entry, int dirty); + +static inline pte_t *contpte_align_down(pte_t *ptep) +{ + return (pte_t *)(ALIGN_DOWN((unsigned long)ptep >> 3, CONT_PTES) << 3); +} + +static inline bool contpte_is_enabled(struct mm_struct *mm) +{ + /* + * Don't attempt to apply the contig bit to kernel mappings, because + * dynamically adding/removing the contig bit can cause page faults. + * These racing faults are ok for user space, since they get serialized + * on the PTL. But kernel mappings can't tolerate faults. + */ + + return mm != &init_mm; +} + +static inline void contpte_try_fold(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, pte_t pte) +{ + /* + * Only bother trying if both the virtual and physical addresses are + * aligned and correspond to the last entry in a contig range. The core + * code mostly modifies ranges from low to high, so this is the likely + * the last modification in the contig range, so a good time to fold. + * We can't fold special mappings, because there is no associated folio. + */ + + bool valign = ((unsigned long)ptep >> 3) % CONT_PTES == CONT_PTES - 1; + bool palign = pte_pfn(pte) % CONT_PTES == CONT_PTES - 1; + + if (contpte_is_enabled(mm) && valign && palign && + pte_valid(pte) && !pte_cont(pte) && !pte_special(pte)) + __contpte_try_fold(mm, addr, ptep, pte); +} + +static inline void contpte_try_unfold(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, pte_t pte) +{ + if (contpte_is_enabled(mm) && pte_valid_cont(pte)) + __contpte_try_unfold(mm, addr, ptep, pte); +} + +/* + * The below functions constitute the public API that arm64 presents to the + * core-mm to manipulate PTE entries within the their page tables (or at least + * this is the subset of the API that arm64 needs to implement). These public + * versions will automatically and transparently apply the contiguous bit where + * it makes sense to do so. Therefore any users that are contig-aware (e.g. + * hugetlb, kernel mapper) should NOT use these APIs, but instead use the + * private versions, which are prefixed with double underscore. All of these + * APIs except for ptep_get_lockless() are expected to be called with the PTL + * held. + */ + +#define ptep_get ptep_get +static inline pte_t ptep_get(pte_t *ptep) +{ + pte_t pte = __ptep_get(ptep); + + if (!pte_valid_cont(pte)) + return pte; + + return contpte_ptep_get(ptep, pte); +} + +#define ptep_get_lockless ptep_get_lockless +static inline pte_t ptep_get_lockless(pte_t *ptep) +{ + pte_t pte = __ptep_get(ptep); + + if (!pte_valid_cont(pte)) + return pte; + + return contpte_ptep_get_lockless(ptep); +} + +static inline void set_pte(pte_t *ptep, pte_t pte) +{ + /* + * We don't have the mm or vaddr so cannot unfold or fold contig entries + * (since it requires tlb maintenance). set_pte() is not used in core + * code, so this should never even be called. Regardless do our best to + * service any call and emit a warning if there is any attempt to set a + * pte on top of an existing contig range. + */ + pte_t orig_pte = __ptep_get(ptep); + + WARN_ON_ONCE(pte_valid_cont(orig_pte)); + __set_pte(ptep, pte_mknoncont(pte)); +} + +#define set_ptes set_ptes +static inline void set_ptes(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, pte_t pte, unsigned int nr) +{ + pte = pte_mknoncont(pte); + + if (!contpte_is_enabled(mm)) + __set_ptes(mm, addr, ptep, pte, nr); + else if (nr == 1) { + contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep)); + __set_ptes(mm, addr, ptep, pte, nr); + contpte_try_fold(mm, addr, ptep, pte); + } else + contpte_set_ptes(mm, addr, ptep, pte, nr); +} + +static inline void pte_clear(struct mm_struct *mm, + unsigned long addr, pte_t *ptep) +{ + contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep)); + __pte_clear(mm, addr, ptep); +} + +#define __HAVE_ARCH_PTEP_GET_AND_CLEAR +static inline pte_t ptep_get_and_clear(struct mm_struct *mm, + unsigned long addr, pte_t *ptep) +{ + contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep)); + return __ptep_get_and_clear(mm, addr, ptep); +} + +#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG +static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, + unsigned long addr, pte_t *ptep) +{ + pte_t orig_pte = __ptep_get(ptep); + + if (!pte_valid_cont(orig_pte)) + return __ptep_test_and_clear_young(vma, addr, ptep); + + return contpte_ptep_test_and_clear_young(vma, addr, ptep); +} + +#define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH +static inline int ptep_clear_flush_young(struct vm_area_struct *vma, + unsigned long addr, pte_t *ptep) +{ + pte_t orig_pte = __ptep_get(ptep); + + if (!pte_valid_cont(orig_pte)) + return __ptep_clear_flush_young(vma, addr, ptep); + + return contpte_ptep_clear_flush_young(vma, addr, ptep); +} + +#define __HAVE_ARCH_PTEP_SET_WRPROTECT +static inline void ptep_set_wrprotect(struct mm_struct *mm, + unsigned long addr, pte_t *ptep) +{ + contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep)); + __ptep_set_wrprotect(mm, addr, ptep); + contpte_try_fold(mm, addr, ptep, __ptep_get(ptep)); +} + +#define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS +static inline int ptep_set_access_flags(struct vm_area_struct *vma, + unsigned long addr, pte_t *ptep, + pte_t entry, int dirty) +{ + pte_t orig_pte = __ptep_get(ptep); + + entry = pte_mknoncont(entry); + + if (!pte_valid_cont(orig_pte)) + return __ptep_set_access_flags(vma, addr, ptep, entry, dirty); + + return contpte_ptep_set_access_flags(vma, addr, ptep, entry, dirty); +} + +#else /* CONFIG_ARM64_CONTPTE */ + #define ptep_get __ptep_get #define set_pte __set_pte #define set_ptes __set_ptes @@ -1131,6 +1331,8 @@ extern void ptep_modify_prot_commit(struct vm_area_struct *vma, #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS #define ptep_set_access_flags __ptep_set_access_flags +#endif /* CONFIG_ARM64_CONTPTE */ + #endif /* !__ASSEMBLY__ */ #endif /* __ASM_PGTABLE_H */ diff --git a/arch/arm64/mm/Makefile b/arch/arm64/mm/Makefile index dbd1bc95967d..60454256945b 100644 --- a/arch/arm64/mm/Makefile +++ b/arch/arm64/mm/Makefile @@ -3,6 +3,7 @@ obj-y := dma-mapping.o extable.o fault.o init.o \ cache.o copypage.o flush.o \ ioremap.o mmap.o pgd.o mmu.o \ context.o proc.o pageattr.o fixmap.o +obj-$(CONFIG_ARM64_CONTPTE) += contpte.o obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o obj-$(CONFIG_PTDUMP_CORE) += ptdump.o obj-$(CONFIG_PTDUMP_DEBUGFS) += ptdump_debugfs.o diff --git a/arch/arm64/mm/contpte.c b/arch/arm64/mm/contpte.c new file mode 100644 index 000000000000..667bcf7c3260 --- /dev/null +++ b/arch/arm64/mm/contpte.c @@ -0,0 +1,351 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2023 ARM Ltd. + */ + +#include +#include +#include + +static void ptep_clear_flush_range(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, int nr) +{ + struct vm_area_struct vma = TLB_FLUSH_VMA(mm, 0); + unsigned long start_addr = addr; + int i; + + for (i = 0; i < nr; i++, ptep++, addr += PAGE_SIZE) + __pte_clear(mm, addr, ptep); + + __flush_tlb_range(&vma, start_addr, addr, PAGE_SIZE, true, 3); +} + +static bool ptep_any_valid(pte_t *ptep, int nr) +{ + int i; + + for (i = 0; i < nr; i++, ptep++) { + if (pte_valid(__ptep_get(ptep))) + return true; + } + + return false; +} + +static void contpte_fold(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, pte_t pte, bool fold) +{ + struct vm_area_struct vma = TLB_FLUSH_VMA(mm, 0); + unsigned long start_addr; + pte_t *start_ptep; + int i; + + start_ptep = ptep = contpte_align_down(ptep); + start_addr = addr = ALIGN_DOWN(addr, CONT_PTE_SIZE); + pte = pfn_pte(ALIGN_DOWN(pte_pfn(pte), CONT_PTES), pte_pgprot(pte)); + pte = fold ? pte_mkcont(pte) : pte_mknoncont(pte); + + for (i = 0; i < CONT_PTES; i++, ptep++, addr += PAGE_SIZE) { + pte_t ptent = __ptep_get_and_clear(mm, addr, ptep); + + if (pte_dirty(ptent)) + pte = pte_mkdirty(pte); + + if (pte_young(ptent)) + pte = pte_mkyoung(pte); + } + + __flush_tlb_range(&vma, start_addr, addr, PAGE_SIZE, true, 3); + + __set_ptes(mm, start_addr, start_ptep, pte, CONT_PTES); +} + +void __contpte_try_fold(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, pte_t pte) +{ + /* + * We have already checked that the virtual and pysical addresses are + * correctly aligned for a contpte mapping in contpte_try_fold() so the + * remaining checks are to ensure that the contpte range is fully + * covered by a single folio, and ensure that all the ptes are valid + * with contiguous PFNs and matching prots. We ignore the state of the + * access and dirty bits for the purpose of deciding if its a contiguous + * range; the folding process will generate a single contpte entry which + * has a single access and dirty bit. Those 2 bits are the logical OR of + * their respective bits in the constituent pte entries. In order to + * ensure the contpte range is covered by a single folio, we must + * recover the folio from the pfn, but special mappings don't have a + * folio backing them. Fortunately contpte_try_fold() already checked + * that the pte is not special - we never try to fold special mappings. + * Note we can't use vm_normal_page() for this since we don't have the + * vma. + */ + + struct page *page = pte_page(pte); + struct folio *folio = page_folio(page); + unsigned long folio_saddr = addr - (page - &folio->page) * PAGE_SIZE; + unsigned long folio_eaddr = folio_saddr + folio_nr_pages(folio) * PAGE_SIZE; + unsigned long cont_saddr = ALIGN_DOWN(addr, CONT_PTE_SIZE); + unsigned long cont_eaddr = cont_saddr + CONT_PTE_SIZE; + unsigned long pfn; + pgprot_t prot; + pte_t subpte; + pte_t *orig_ptep; + int i; + + if (folio_saddr > cont_saddr || folio_eaddr < cont_eaddr) + return; + + pfn = pte_pfn(pte) - ((addr - cont_saddr) >> PAGE_SHIFT); + prot = pte_pgprot(pte_mkold(pte_mkclean(pte))); + orig_ptep = ptep; + ptep = contpte_align_down(ptep); + + for (i = 0; i < CONT_PTES; i++, ptep++, pfn++) { + subpte = __ptep_get(ptep); + subpte = pte_mkold(pte_mkclean(subpte)); + + if (!pte_valid(subpte) || + pte_pfn(subpte) != pfn || + pgprot_val(pte_pgprot(subpte)) != pgprot_val(prot)) + return; + } + + contpte_fold(mm, addr, orig_ptep, pte, true); +} +EXPORT_SYMBOL(__contpte_try_fold); + +void __contpte_try_unfold(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, pte_t pte) +{ + /* + * We have already checked that the ptes are contiguous in + * contpte_try_unfold(), so we can unfold unconditionally here. + */ + + contpte_fold(mm, addr, ptep, pte, false); +} +EXPORT_SYMBOL(__contpte_try_unfold); + +pte_t contpte_ptep_get(pte_t *ptep, pte_t orig_pte) +{ + /* + * Gather access/dirty bits, which may be populated in any of the ptes + * of the contig range. We are guarranteed to be holding the PTL, so any + * contiguous range cannot be unfolded or otherwise modified under our + * feet. + */ + + pte_t pte; + int i; + + ptep = contpte_align_down(ptep); + + for (i = 0; i < CONT_PTES; i++, ptep++) { + pte = __ptep_get(ptep); + + if (pte_dirty(pte)) + orig_pte = pte_mkdirty(orig_pte); + + if (pte_young(pte)) + orig_pte = pte_mkyoung(orig_pte); + } + + return orig_pte; +} +EXPORT_SYMBOL(contpte_ptep_get); + +pte_t contpte_ptep_get_lockless(pte_t *orig_ptep) +{ + /* + * Gather access/dirty bits, which may be populated in any of the ptes + * of the contig range. We may not be holding the PTL, so any contiguous + * range may be unfolded/modified/refolded under our feet. Therefore we + * ensure we read a _consistent_ contpte range by checking that all ptes + * in the range are valid and have CONT_PTE set, that all pfns are + * contiguous and that all pgprots are the same (ignoring access/dirty). + * If we find a pte that is not consistent, then we must be racing with + * an update so start again. If the target pte does not have CONT_PTE + * set then that is considered consistent on its own because it is not + * part of a contpte range. + */ + + pte_t orig_pte; + pgprot_t orig_prot; + pte_t *ptep; + unsigned long pfn; + pte_t pte; + pgprot_t prot; + int i; + +retry: + orig_pte = __ptep_get(orig_ptep); + + if (!pte_valid_cont(orig_pte)) + return orig_pte; + + orig_prot = pte_pgprot(pte_mkold(pte_mkclean(orig_pte))); + ptep = contpte_align_down(orig_ptep); + pfn = pte_pfn(orig_pte) - (orig_ptep - ptep); + + for (i = 0; i < CONT_PTES; i++, ptep++, pfn++) { + pte = __ptep_get(ptep); + prot = pte_pgprot(pte_mkold(pte_mkclean(pte))); + + if (!pte_valid_cont(pte) || + pte_pfn(pte) != pfn || + pgprot_val(prot) != pgprot_val(orig_prot)) + goto retry; + + if (pte_dirty(pte)) + orig_pte = pte_mkdirty(orig_pte); + + if (pte_young(pte)) + orig_pte = pte_mkyoung(orig_pte); + } + + return orig_pte; +} +EXPORT_SYMBOL(contpte_ptep_get_lockless); + +void contpte_set_ptes(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, pte_t pte, unsigned int nr) +{ + unsigned long next; + unsigned long end = addr + (nr << PAGE_SHIFT); + unsigned long pfn = pte_pfn(pte); + pgprot_t prot = pte_pgprot(pte); + pte_t orig_pte; + + do { + next = pte_cont_addr_end(addr, end); + nr = (next - addr) >> PAGE_SHIFT; + pte = pfn_pte(pfn, prot); + + if (((addr | next | (pfn << PAGE_SHIFT)) & ~CONT_PTE_MASK) == 0) + pte = pte_mkcont(pte); + else + pte = pte_mknoncont(pte); + + /* + * If operating on a partial contiguous range then we must first + * unfold the contiguous range if it was previously folded. + * Otherwise we could end up with overlapping tlb entries. + */ + if (nr != CONT_PTES) + contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep)); + + /* + * If we are replacing ptes that were contiguous or if the new + * ptes are contiguous and any of the ptes being replaced are + * valid, we need to clear and flush the range to prevent + * overlapping tlb entries. + */ + orig_pte = __ptep_get(ptep); + if (pte_valid_cont(orig_pte) || + (pte_cont(pte) && ptep_any_valid(ptep, nr))) + ptep_clear_flush_range(mm, addr, ptep, nr); + + __set_ptes(mm, addr, ptep, pte, nr); + + addr = next; + ptep += nr; + pfn += nr; + + } while (addr != end); +} +EXPORT_SYMBOL(contpte_set_ptes); + +int contpte_ptep_test_and_clear_young(struct vm_area_struct *vma, + unsigned long addr, pte_t *ptep) +{ + /* + * ptep_clear_flush_young() technically requires us to clear the access + * flag for a _single_ pte. However, the core-mm code actually tracks + * access/dirty per folio, not per page. And since we only create a + * contig range when the range is covered by a single folio, we can get + * away with clearing young for the whole contig range here, so we avoid + * having to unfold. + */ + + int i; + int young = 0; + + ptep = contpte_align_down(ptep); + addr = ALIGN_DOWN(addr, CONT_PTE_SIZE); + + for (i = 0; i < CONT_PTES; i++, ptep++, addr += PAGE_SIZE) + young |= __ptep_test_and_clear_young(vma, addr, ptep); + + return young; +} +EXPORT_SYMBOL(contpte_ptep_test_and_clear_young); + +int contpte_ptep_clear_flush_young(struct vm_area_struct *vma, + unsigned long addr, pte_t *ptep) +{ + int young; + + young = contpte_ptep_test_and_clear_young(vma, addr, ptep); + + if (young) { + /* + * See comment in __ptep_clear_flush_young(); same rationale for + * eliding the trailing DSB applies here. + */ + addr = ALIGN_DOWN(addr, CONT_PTE_SIZE); + __flush_tlb_range_nosync(vma, addr, addr + CONT_PTE_SIZE, + PAGE_SIZE, true, 3); + } + + return young; +} +EXPORT_SYMBOL(contpte_ptep_clear_flush_young); + +int contpte_ptep_set_access_flags(struct vm_area_struct *vma, + unsigned long addr, pte_t *ptep, + pte_t entry, int dirty) +{ + pte_t orig_pte; + int i; + unsigned long start_addr; + + /* + * Gather the access/dirty bits for the contiguous range. If nothing has + * changed, its a noop. + */ + orig_pte = ptep_get(ptep); + if (pte_val(orig_pte) == pte_val(entry)) + return 0; + + /* + * We can fix up access/dirty bits without having to unfold/fold the + * contig range. But if the write bit is changing, we need to go through + * the full unfold/fold cycle. + */ + if (pte_write(orig_pte) == pte_write(entry)) { + /* + * For HW access management, we technically only need to update + * the flag on a single pte in the range. But for SW access + * management, we need to update all the ptes to prevent extra + * faults. Avoid per-page tlb flush in __ptep_set_access_flags() + * and instead flush the whole range at the end. + */ + ptep = contpte_align_down(ptep); + start_addr = addr = ALIGN_DOWN(addr, CONT_PTE_SIZE); + + for (i = 0; i < CONT_PTES; i++, ptep++, addr += PAGE_SIZE) + __ptep_set_access_flags(vma, addr, ptep, entry, 0); + + if (dirty) + __flush_tlb_range(vma, start_addr, addr, + PAGE_SIZE, true, 3); + } else { + __contpte_try_unfold(vma->vm_mm, addr, ptep, orig_pte); + __ptep_set_access_flags(vma, addr, ptep, entry, dirty); + contpte_try_fold(vma->vm_mm, addr, ptep, entry); + } + + return 1; +} +EXPORT_SYMBOL(contpte_ptep_set_access_flags); From patchwork Wed Nov 15 16:30:17 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ryan Roberts X-Patchwork-Id: 165478 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b909:0:b0:403:3b70:6f57 with SMTP id t9csp2657659vqg; Wed, 15 Nov 2023 08:33:42 -0800 (PST) X-Google-Smtp-Source: AGHT+IGfL0OlocKhbLeBoMVC4eUzELmd2tp8GFJAs1oJw3OKXOH8T5OHpyjNp4SRcusy0ub/fqqO X-Received: by 2002:a17:902:7597:b0:1c3:4b24:d89d with SMTP id j23-20020a170902759700b001c34b24d89dmr5852618pll.40.1700066021730; Wed, 15 Nov 2023 08:33:41 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1700066021; cv=none; d=google.com; s=arc-20160816; b=U/LquvL4c6GsDnay+c8Az80b1VTpH2XYb5S/6aRyJ/EuV0UA1XnmxGEZNbneKMYnZO yogRGNrWCgY3Te73FRtwSt2x5W/x1DEd5HWPriF9a/T2UhmgIvKvxpCVe6mUDRvZTAml jCrzhp2vCZ/QJDoou284M65JXab3F60mUd5iDVihRBWXgJESYAFGZRlQZNEeNT2a0ary MkLPTrFcSlGHbBlP6ve1EzIFFJOpJwJw29KFqDaL/3+FxH706Rvk7bPbLTsKqz1/mMiL 19DhA8c+J3FmU07I5JZyL3mTJQ/3YD8BIaNrOGEqM24TJ93u04K1hO7P4z1ath2NqY5G oXFw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from; bh=bsYZKHoCNNIKvSKeL5iLaAvAxp8A686Xb5jxLzFpFHw=; fh=CVYMMnwSLqNeTtsgqDZkAN2xp/CPaSWpO0DiPqQVZ5w=; b=TdXLfxnGAvzLVCKU6+cyJR66/Vx1P7tJZHzN9G1mRjYEjv/Fa1gj8TwB/dqjqRcbr9 i7EdQNIkB/v5sRAOITc6Ak5Nogm51NabVucG4PI51uDFmIsxgoK2utg1s0C+BOHECoBY AoZCBdGKX2bSKYRtQc53payHwm6NDf5uobJwd1YFtdJr9KkQQBudxsLF0ggv072tsIe1 /fc6KgD1JfRp/7q6DRoyD0NcKFXdaGlXImjPf9YRnYj3EGQFGs6xrUEYnedMx8IoidGJ oncnBCXOoh6DGqlLXwZd4Ati1DR5QgyZTB/MUbKcErac7PMhkqKKrq+YwCkax9qPo1ph X1yw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from snail.vger.email (snail.vger.email. [2620:137:e000::3:7]) by mx.google.com with ESMTPS id w13-20020a170902e88d00b001bf5c12ea06si10668634plg.404.2023.11.15.08.33.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Nov 2023 08:33:41 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) client-ip=2620:137:e000::3:7; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by snail.vger.email (Postfix) with ESMTP id 920198212AB7; Wed, 15 Nov 2023 08:32:15 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at snail.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232414AbjKOQcD (ORCPT + 29 others); Wed, 15 Nov 2023 11:32:03 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38634 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232718AbjKOQbd (ORCPT ); Wed, 15 Nov 2023 11:31:33 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 02D241BE7 for ; Wed, 15 Nov 2023 08:31:15 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 3633F15DB; Wed, 15 Nov 2023 08:32:01 -0800 (PST) Received: from e125769.cambridge.arm.com (e125769.cambridge.arm.com [10.1.196.26]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 7CAC83F641; Wed, 15 Nov 2023 08:31:12 -0800 (PST) From: Ryan Roberts To: Catalin Marinas , Will Deacon , Ard Biesheuvel , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Zenghui Yu , Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Andrew Morton , Anshuman Khandual , Matthew Wilcox , Yu Zhao , Mark Rutland , David Hildenbrand , Kefeng Wang , John Hubbard , Zi Yan Cc: Ryan Roberts , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 13/14] arm64/mm: Implement ptep_set_wrprotects() to optimize fork() Date: Wed, 15 Nov 2023 16:30:17 +0000 Message-Id: <20231115163018.1303287-14-ryan.roberts@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231115163018.1303287-1-ryan.roberts@arm.com> References: <20231115163018.1303287-1-ryan.roberts@arm.com> MIME-Version: 1.0 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_BLOCKED,SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (snail.vger.email [0.0.0.0]); Wed, 15 Nov 2023 08:32:15 -0800 (PST) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1782648428789157789 X-GMAIL-MSGID: 1782648428789157789 With the core-mm changes in place to batch-copy ptes during fork, we can take advantage of this in arm64 to greatly reduce the number of tlbis we have to issue, and recover the lost fork performance incured when adding support for transparent contiguous ptes. If we are write-protecting a whole contig range, we can apply the write-protection to the whole range and know that it won't change whether the range should have the contiguous bit set or not. For ranges smaller than the contig range, we will still have to unfold, apply the write-protection, then fold if the change now means the range is foldable. This optimization is possible thanks to the tightening of the Arm ARM in respect to the definition and behaviour when 'Misprogramming the Contiguous bit'. See section D21194 at https://developer.arm.com/documentation/102105/latest/ Performance tested with the following test written for the will-it-scale framework: ------- char *testcase_description = "fork and exit"; void testcase(unsigned long long *iterations, unsigned long nr) { int pid; char *mem; mem = malloc(SZ_128M); assert(mem); memset(mem, 1, SZ_128M); while (1) { pid = fork(); assert(pid >= 0); if (!pid) exit(0); waitpid(pid, NULL, 0); (*iterations)++; } } ------- I see huge performance regression when PTE_CONT support was added, then the regression is mostly fixed with the addition of this change. The following shows regression relative to before PTE_CONT was enabled (bigger negative value is bigger regression): | cpus | before opt | after opt | |-------:|-------------:|------------:| | 1 | -10.4% | -5.2% | | 8 | -15.4% | -3.5% | | 16 | -38.7% | -3.7% | | 24 | -57.0% | -4.4% | | 32 | -65.8% | -5.4% | Signed-off-by: Ryan Roberts --- arch/arm64/include/asm/pgtable.h | 30 ++++++++++++++++++++--- arch/arm64/mm/contpte.c | 42 ++++++++++++++++++++++++++++++++ 2 files changed, 69 insertions(+), 3 deletions(-) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 15bc9cf1eef4..9bd2f57a9e11 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -984,6 +984,16 @@ static inline void __ptep_set_wrprotect(struct mm_struct *mm, } while (pte_val(pte) != pte_val(old_pte)); } +static inline void __ptep_set_wrprotects(struct mm_struct *mm, + unsigned long address, pte_t *ptep, + unsigned int nr) +{ + unsigned int i; + + for (i = 0; i < nr; i++, address += PAGE_SIZE, ptep++) + __ptep_set_wrprotect(mm, address, ptep); +} + #ifdef CONFIG_TRANSPARENT_HUGEPAGE #define __HAVE_ARCH_PMDP_SET_WRPROTECT static inline void pmdp_set_wrprotect(struct mm_struct *mm, @@ -1139,6 +1149,8 @@ extern int contpte_ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep); extern int contpte_ptep_clear_flush_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep); +extern void contpte_set_wrprotects(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, unsigned int nr); extern int contpte_ptep_set_access_flags(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep, pte_t entry, int dirty); @@ -1290,13 +1302,25 @@ static inline int ptep_clear_flush_young(struct vm_area_struct *vma, return contpte_ptep_clear_flush_young(vma, addr, ptep); } +#define ptep_set_wrprotects ptep_set_wrprotects +static inline void ptep_set_wrprotects(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, unsigned int nr) +{ + if (!contpte_is_enabled(mm)) + __ptep_set_wrprotects(mm, addr, ptep, nr); + else if (nr == 1) { + contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep)); + __ptep_set_wrprotects(mm, addr, ptep, 1); + contpte_try_fold(mm, addr, ptep, __ptep_get(ptep)); + } else + contpte_set_wrprotects(mm, addr, ptep, nr); +} + #define __HAVE_ARCH_PTEP_SET_WRPROTECT static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep)); - __ptep_set_wrprotect(mm, addr, ptep); - contpte_try_fold(mm, addr, ptep, __ptep_get(ptep)); + ptep_set_wrprotects(mm, addr, ptep, 1); } #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS diff --git a/arch/arm64/mm/contpte.c b/arch/arm64/mm/contpte.c index 667bcf7c3260..426be9cd4dea 100644 --- a/arch/arm64/mm/contpte.c +++ b/arch/arm64/mm/contpte.c @@ -302,6 +302,48 @@ int contpte_ptep_clear_flush_young(struct vm_area_struct *vma, } EXPORT_SYMBOL(contpte_ptep_clear_flush_young); +void contpte_set_wrprotects(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, unsigned int nr) +{ + unsigned long next; + unsigned long end = addr + (nr << PAGE_SHIFT); + + do { + next = pte_cont_addr_end(addr, end); + nr = (next - addr) >> PAGE_SHIFT; + + /* + * If wrprotecting an entire contig range, we can avoid + * unfolding. Just set wrprotect and wait for the later + * mmu_gather flush to invalidate the tlb. Until the flush, the + * page may or may not be wrprotected. After the flush, it is + * guarranteed wrprotected. If its a partial range though, we + * must unfold, because we can't have a case where CONT_PTE is + * set but wrprotect applies to a subset of the PTEs; this would + * cause it to continue to be unpredictable after the flush. + */ + if (nr != CONT_PTES) + contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep)); + + __ptep_set_wrprotects(mm, addr, ptep, nr); + + addr = next; + ptep += nr; + + /* + * If applying to a partial contig range, the change could have + * made the range foldable. Use the last pte in the range we + * just set for comparison, since contpte_try_fold() only + * triggers when acting on the last pte in the contig range. + */ + if (nr != CONT_PTES) + contpte_try_fold(mm, addr - PAGE_SIZE, ptep - 1, + __ptep_get(ptep - 1)); + + } while (addr != end); +} +EXPORT_SYMBOL(contpte_set_wrprotects); + int contpte_ptep_set_access_flags(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep, pte_t entry, int dirty) From patchwork Wed Nov 15 16:30:18 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ryan Roberts X-Patchwork-Id: 165475 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b909:0:b0:403:3b70:6f57 with SMTP id t9csp2657432vqg; Wed, 15 Nov 2023 08:33:23 -0800 (PST) X-Google-Smtp-Source: AGHT+IG+kZXR3pJ87J4RtJ91HTqvodo/qxno5nTBONMTNbUBt+Be5gvi1l20tTjHRbF3MXHepk7b X-Received: by 2002:a17:903:2301:b0:1cc:589d:e584 with SMTP id d1-20020a170903230100b001cc589de584mr6986205plh.16.1700066003133; Wed, 15 Nov 2023 08:33:23 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1700066003; cv=none; d=google.com; s=arc-20160816; b=vh2nwbrjdpSwcrTNSF1Wso0bVGDnwyM6E1GdAtlFR8PU/Q7VXNxzqi3qK47IDmAKk3 G/ONmjZZ8PBPO5Ws8YLJzPVufAFquCZTq1S7V9slImsfz+WYafkMwQTzsdbqAjk9vFm2 TXvSDnZlfTaCTw1BrCIfCH16p9CZxBcYCKvdy+NxlS3OXb8FUU8A/w/VmVcQjtlwaIxd ETw3RHdKc+JEVSyf1G1HvbS0UgxrlQ83GHeIKgiri5Soj8b38oVSZRhURvyqpaJI6Ekv a+aZaYbyVk79mjeQDQPeN0GqTQVrTinRXtjh2V8PiyapryFW9Xp0tWbb09MIVAOzmsJS GBRQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from; bh=h/mVzRBx3ll1YC9aC0+oEdCQl+yNhkPnsqUfdHZE74A=; fh=CVYMMnwSLqNeTtsgqDZkAN2xp/CPaSWpO0DiPqQVZ5w=; b=Rw7J2ABruxlzEHZuJk8GL+iqrBEVoe5yowGff+RpdPyWWGBHhAf7AZ3Mj5ROxi5NG0 t1y+adddiP+TtHi+Qw1iKKD0izdruc8blMHj9oJMvHTKf2ON6OZ+sL6aK6OXQcIHvXcA 1OHd05P8X6WOl2sjnbKEvjEQcTph8dOmzv2Q3J2dVFHnCZwA35N3Ff0FTqOpMPfo6jgA buky3QceX9AWBYV2qxQidl/w9YfQW/u7dPt60j3Prkkv6oA2q2ZpHulo+8F4iw3kxezZ YwRJSELHcmwHsn7m/8enz95oNA8kOr91cjBgAfoYCh9OgnOQyEizOvrH7usa1ovX7XrK w2rg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.35 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from groat.vger.email (groat.vger.email. [23.128.96.35]) by mx.google.com with ESMTPS id bx34-20020a056a02052200b00585a02550e1si11453467pgb.50.2023.11.15.08.33.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Nov 2023 08:33:23 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.35 as permitted sender) client-ip=23.128.96.35; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.35 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by groat.vger.email (Postfix) with ESMTP id 1082D802A03D; Wed, 15 Nov 2023 08:33:04 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at groat.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232626AbjKOQcH (ORCPT + 29 others); Wed, 15 Nov 2023 11:32:07 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36498 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232616AbjKOQbk (ORCPT ); Wed, 15 Nov 2023 11:31:40 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 175DDD57 for ; Wed, 15 Nov 2023 08:31:19 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 7B84FDA7; Wed, 15 Nov 2023 08:32:04 -0800 (PST) Received: from e125769.cambridge.arm.com (e125769.cambridge.arm.com [10.1.196.26]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id C1AE63F641; Wed, 15 Nov 2023 08:31:15 -0800 (PST) From: Ryan Roberts To: Catalin Marinas , Will Deacon , Ard Biesheuvel , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Zenghui Yu , Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Andrew Morton , Anshuman Khandual , Matthew Wilcox , Yu Zhao , Mark Rutland , David Hildenbrand , Kefeng Wang , John Hubbard , Zi Yan Cc: Ryan Roberts , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 14/14] arm64/mm: Add ptep_get_and_clear_full() to optimize process teardown Date: Wed, 15 Nov 2023 16:30:18 +0000 Message-Id: <20231115163018.1303287-15-ryan.roberts@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231115163018.1303287-1-ryan.roberts@arm.com> References: <20231115163018.1303287-1-ryan.roberts@arm.com> MIME-Version: 1.0 X-Spam-Status: No, score=-0.8 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on groat.vger.email Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (groat.vger.email [0.0.0.0]); Wed, 15 Nov 2023 08:33:04 -0800 (PST) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1782648409428361673 X-GMAIL-MSGID: 1782648409428361673 ptep_get_and_clear_full() adds a 'full' parameter which is not present for the fallback ptep_get_and_clear() function. 'full' is set to 1 when a full address space teardown is in progress. We use this information to optimize arm64_sys_exit_group() by avoiding unfolding (and therefore tlbi) contiguous ranges. Instead we just clear the PTE but allow all the contiguous neighbours to keep their contig bit set, because we know we are about to clear the rest too. Before this optimization, the cost of arm64_sys_exit_group() exploded to 32x what it was before PTE_CONT support was wired up, when compiling the kernel. With this optimization in place, we are back down to the original cost. This approach is not perfect though, as for the duration between returning from the first call to ptep_get_and_clear_full() and making the final call, the contpte block in an intermediate state, where some ptes are cleared and others are still set with the PTE_CONT bit. If any other APIs are called for the ptes in the contpte block during that time, we have to be very careful. The core code currently interleaves calls to ptep_get_and_clear_full() with ptep_get() and so ptep_get() must be careful to ignore the cleared entries when accumulating the access and dirty bits - the same goes for ptep_get_lockless(). The only other calls we might resonably expect are to set markers in the previously cleared ptes. (We shouldn't see valid entries being set until after the tlbi, at which point we are no longer in the intermediate state). Since markers are not valid, this is safe; set_ptes() will see the old, invalid entry and will not attempt to unfold. And the new pte is also invalid so it won't attempt to fold. We shouldn't see this for the 'full' case anyway. The last remaining issue is returning the access/dirty bits. That info could be present in any of the ptes in the contpte block. ptep_get() will gather those bits from across the contpte block. We don't bother doing that here, because we know that the information is used by the core-mm to mark the underlying folio as accessed/dirty. And since the same folio must be underpinning the whole block (that was a requirement for folding in the first place), that information will make it to the folio eventually once all the ptes have been cleared. This approach means we don't have to play games with accumulating and storing the bits. It does mean that any interleaved calls to ptep_get() may lack correct access/dirty information if we have already cleared the pte that happened to store it. The core code does not rely on this though. Signed-off-by: Ryan Roberts --- arch/arm64/include/asm/pgtable.h | 18 +++++++++-- arch/arm64/mm/contpte.c | 54 ++++++++++++++++++++++++++++++++ 2 files changed, 70 insertions(+), 2 deletions(-) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 9bd2f57a9e11..ea58a9f4e700 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -1145,6 +1145,8 @@ extern pte_t contpte_ptep_get(pte_t *ptep, pte_t orig_pte); extern pte_t contpte_ptep_get_lockless(pte_t *orig_ptep); extern void contpte_set_ptes(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pte, unsigned int nr); +extern pte_t contpte_ptep_get_and_clear_full(struct mm_struct *mm, + unsigned long addr, pte_t *ptep); extern int contpte_ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep); extern int contpte_ptep_clear_flush_young(struct vm_area_struct *vma, @@ -1270,12 +1272,24 @@ static inline void pte_clear(struct mm_struct *mm, __pte_clear(mm, addr, ptep); } +#define __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL +static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm, + unsigned long addr, pte_t *ptep, int full) +{ + pte_t orig_pte = __ptep_get(ptep); + + if (!pte_valid_cont(orig_pte) || !full) { + contpte_try_unfold(mm, addr, ptep, orig_pte); + return __ptep_get_and_clear(mm, addr, ptep); + } else + return contpte_ptep_get_and_clear_full(mm, addr, ptep); +} + #define __HAVE_ARCH_PTEP_GET_AND_CLEAR static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep)); - return __ptep_get_and_clear(mm, addr, ptep); + return ptep_get_and_clear_full(mm, addr, ptep, 0); } #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG diff --git a/arch/arm64/mm/contpte.c b/arch/arm64/mm/contpte.c index 426be9cd4dea..5d1aaed82d32 100644 --- a/arch/arm64/mm/contpte.c +++ b/arch/arm64/mm/contpte.c @@ -144,6 +144,14 @@ pte_t contpte_ptep_get(pte_t *ptep, pte_t orig_pte) for (i = 0; i < CONT_PTES; i++, ptep++) { pte = __ptep_get(ptep); + /* + * Deal with the partial contpte_ptep_get_and_clear_full() case, + * where some of the ptes in the range may be cleared but others + * are still to do. See contpte_ptep_get_and_clear_full(). + */ + if (pte_val(pte) == 0) + continue; + if (pte_dirty(pte)) orig_pte = pte_mkdirty(orig_pte); @@ -256,6 +264,52 @@ void contpte_set_ptes(struct mm_struct *mm, unsigned long addr, } EXPORT_SYMBOL(contpte_set_ptes); +pte_t contpte_ptep_get_and_clear_full(struct mm_struct *mm, + unsigned long addr, pte_t *ptep) +{ + /* + * When doing a full address space teardown, we can avoid unfolding the + * contiguous range, and therefore avoid the associated tlbi. Instead, + * just get and clear the pte. The caller is promising to call us for + * every pte, so every pte in the range will be cleared by the time the + * tlbi is issued. + * + * This approach is not perfect though, as for the duration between + * returning from the first call to ptep_get_and_clear_full() and making + * the final call, the contpte block in an intermediate state, where + * some ptes are cleared and others are still set with the PTE_CONT bit. + * If any other APIs are called for the ptes in the contpte block during + * that time, we have to be very careful. The core code currently + * interleaves calls to ptep_get_and_clear_full() with ptep_get() and so + * ptep_get() must be careful to ignore the cleared entries when + * accumulating the access and dirty bits - the same goes for + * ptep_get_lockless(). The only other calls we might resonably expect + * are to set markers in the previously cleared ptes. (We shouldn't see + * valid entries being set until after the tlbi, at which point we are + * no longer in the intermediate state). Since markers are not valid, + * this is safe; set_ptes() will see the old, invalid entry and will not + * attempt to unfold. And the new pte is also invalid so it won't + * attempt to fold. We shouldn't see this for the 'full' case anyway. + * + * The last remaining issue is returning the access/dirty bits. That + * info could be present in any of the ptes in the contpte block. + * ptep_get() will gather those bits from across the contpte block. We + * don't bother doing that here, because we know that the information is + * used by the core-mm to mark the underlying folio as accessed/dirty. + * And since the same folio must be underpinning the whole block (that + * was a requirement for folding in the first place), that information + * will make it to the folio eventually once all the ptes have been + * cleared. This approach means we don't have to play games with + * accumulating and storing the bits. It does mean that any interleaved + * calls to ptep_get() may lack correct access/dirty information if we + * have already cleared the pte that happened to store it. The core code + * does not rely on this though. + */ + + return __ptep_get_and_clear(mm, addr, ptep); +} +EXPORT_SYMBOL(contpte_ptep_get_and_clear_full); + int contpte_ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep) {