From patchwork Thu Jan 5 10:18:16 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Houghton X-Patchwork-Id: 39455 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a5d:4e01:0:0:0:0:0 with SMTP id p1csp228030wrt; Thu, 5 Jan 2023 02:23:25 -0800 (PST) X-Google-Smtp-Source: AMrXdXvRiLDpbWrQQih8CNFzgov3byYh/V7gQgyRnZWk3LTVPcQLDdfmURXK6kSjTtRS7eXFeAmK X-Received: by 2002:a05:6a20:4655:b0:aa:23f9:7314 with SMTP id eb21-20020a056a20465500b000aa23f97314mr52326938pzb.46.1672914205472; Thu, 05 Jan 2023 02:23:25 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1672914205; cv=none; d=google.com; s=arc-20160816; b=x9QMfYMAhyvNrfZ7ccV5MRHB2pA0vQyMkS2wE0xrrRI+qSMSucuXyPPPW04w0MS4uB 3IrgTR5Wobi6cWhyqdLBQpAXzbe0/rubNIB5BzPWzATQREZjSp8jSnWKDHVhnWjbKovm KvT1aCur6LeANouS3A8i0fPzVx6Df6SOcxEHcgLaYm129xo15/NlsW80lZZjKiWoHo/R YysV1dS0ljf9dmLAASoPTFe34pteExRqg+8Hgnu1B95mtrP3LpoCY4LEhqXdfh2NwZ9V tt2i30V7+0+h7ZUTcJLrMUYdqd0/taRCEB4flbygNiAYudkZLPpfsugdn03lgPZvy9gg ziRA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:cc:to:from:subject:message-id:references :mime-version:in-reply-to:date:dkim-signature; bh=lp3NkrzzsDy9ah3gYP7Di6ebFhCh/hI0r9EhbhKs3qA=; b=P0QSsHEpQFx9hEqvcXwBjoMSjAHWy4CaMnsqky5lUQn7xSgXtxARLIrzEpQpAavb1o ZqV+vJcnqDqa1MS1FH0HHy0j0Me1ahSVKUiUzhbmUkrmANzKII5UQjwgQvBqaci7fc99 6so405tnfvZMyWUAMCOKjlSpfH72JMWJq1uNXXDAVaJhRmyJuRhUYmA1v+6eJmCsOvho vi2e543Yy1yhp+1xpziUqDEJYZUfEzVofpBrZnQ6q5fuc3hlgK3nsR3EGaa1smkP2lB8 noAkGb90S5tmEi3AnMDZNRujUIWD/vo7grdvGWib4x36O7m6BdPK48cP81TD5L1krNry /Hkg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@google.com header.s=20210112 header.b=gcqO4fum; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id k23-20020a63ba17000000b004626957c3c7si39553255pgf.193.2023.01.05.02.23.12; Thu, 05 Jan 2023 02:23:25 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20210112 header.b=gcqO4fum; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232650AbjAEKVK (ORCPT + 99 others); Thu, 5 Jan 2023 05:21:10 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40490 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232741AbjAEKT5 (ORCPT ); Thu, 5 Jan 2023 05:19:57 -0500 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 44A63559C2 for ; Thu, 5 Jan 2023 02:19:22 -0800 (PST) Received: by mail-yb1-xb49.google.com with SMTP id y66-20020a25c845000000b00733b5049b6fso36235986ybf.3 for ; Thu, 05 Jan 2023 02:19:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=lp3NkrzzsDy9ah3gYP7Di6ebFhCh/hI0r9EhbhKs3qA=; b=gcqO4fumRx0zgQZPFIbbvhj2RDn3uzOiEjenn5HSn/KoUqOlS6cvCBPlQZqdnokXAv yuBgbgVdZ68dWkcgWO302Mw9PxijLJ23xw6JxoY2ObqFFf3QxAWs1BdbmgNwKsp6kjEu 8GFqq0LZlvusyfldGmkc6FfTZZ/RbptJV8SUrxL5hGv7ZFxVYZY2rxA32ezUN4HQKndZ n4NkO1TfQAKi7YjlKvn942sD0+vyg8DNgNqttkJLun2/ieyUyjjedHWOdKf/Toc3RDXd NYkM9a5g7CgZdcmSy/hZ0BvTwMl6CAeI0KwuHwV/HKzTEVBfjxeq4ELE0Z8GmCd1b9Ya 6emg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=lp3NkrzzsDy9ah3gYP7Di6ebFhCh/hI0r9EhbhKs3qA=; b=R8SICv1wYg3x3KFPJulWGMRhG124aXwkCJfttKj8x6001atFQHIAFFnfjSoFWLBE4Q HONNi0Hny5r5CpD125qflLBxc2dL0BP6WHOPRK6LXM2R3G1Y6/00MQIuIjTLVcQ6UhxV idFfCZYPj2qRkigrFOEnM69TNDZjrpEHSEeeSmuUWq/bjuCuKbUp82JyNywbfArniG7S GueWfLjmHGLa7o8R1dtDZ/4FvMD4e4iC42Tr5ALwS7pzxRgganTmbd9BOUBdK6oKWgtd +3DprPyV8GnEEkJqR5D6JlU95yTj2GkSFDimvPHBchNF70rZFc5gkAisOQS86Xcpg2MO M9jA== X-Gm-Message-State: AFqh2krCTcQG4vr4N8fM/breQyUs39o1Rpdm9H9t03bbJFij4/2svi0d 9JQ9RZY9k6qS3h6Ua2u45Z9TiYUO+FIMIp7y X-Received: from jthoughton.c.googlers.com ([fda3:e722:ac3:cc00:14:4d90:c0a8:2a4f]) (user=jthoughton job=sendgmr) by 2002:a25:13c2:0:b0:716:10cb:dc2e with SMTP id 185-20020a2513c2000000b0071610cbdc2emr6990557ybt.530.1672913962037; Thu, 05 Jan 2023 02:19:22 -0800 (PST) Date: Thu, 5 Jan 2023 10:18:16 +0000 In-Reply-To: <20230105101844.1893104-1-jthoughton@google.com> Mime-Version: 1.0 References: <20230105101844.1893104-1-jthoughton@google.com> X-Mailer: git-send-email 2.39.0.314.g84b9a713c41-goog Message-ID: <20230105101844.1893104-19-jthoughton@google.com> Subject: [PATCH 18/46] hugetlb: add HGM support for hugetlb_change_protection From: James Houghton To: Mike Kravetz , Muchun Song , Peter Xu Cc: David Hildenbrand , David Rientjes , Axel Rasmussen , Mina Almasry , "Zach O'Keefe" , Manish Mishra , Naoya Horiguchi , "Dr . David Alan Gilbert" , "Matthew Wilcox (Oracle)" , Vlastimil Babka , Baolin Wang , Miaohe Lin , Yang Shi , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, James Houghton X-Spam-Status: No, score=-9.6 required=5.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1754177685844195303?= X-GMAIL-MSGID: =?utf-8?q?1754177685844195303?= The main change here is to do a high-granularity walk and pulling the shift from the walk (not from the hstate). Signed-off-by: James Houghton --- mm/hugetlb.c | 59 +++++++++++++++++++++++++++++++++------------------- 1 file changed, 38 insertions(+), 21 deletions(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index dfd6c1491ac3..73672d806172 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -6798,15 +6798,15 @@ unsigned long hugetlb_change_protection(struct vm_area_struct *vma, { struct mm_struct *mm = vma->vm_mm; unsigned long start = address; - pte_t *ptep; pte_t pte; struct hstate *h = hstate_vma(vma); - unsigned long pages = 0, psize = huge_page_size(h); + unsigned long base_pages = 0, psize = huge_page_size(h); bool shared_pmd = false; struct mmu_notifier_range range; unsigned long last_addr_mask; bool uffd_wp = cp_flags & MM_CP_UFFD_WP; bool uffd_wp_resolve = cp_flags & MM_CP_UFFD_WP_RESOLVE; + struct hugetlb_pte hpte; /* * In the case of shared PMDs, the area to flush could be beyond @@ -6824,28 +6824,30 @@ unsigned long hugetlb_change_protection(struct vm_area_struct *vma, hugetlb_vma_lock_write(vma); i_mmap_lock_write(vma->vm_file->f_mapping); last_addr_mask = hugetlb_mask_last_page(h); - for (; address < end; address += psize) { + while (address < end) { spinlock_t *ptl; - ptep = hugetlb_walk(vma, address, psize); - if (!ptep) { - address |= last_addr_mask; + + if (hugetlb_full_walk(&hpte, vma, address)) { + address = (address | last_addr_mask) + psize; continue; } - ptl = huge_pte_lock(h, mm, ptep); - if (huge_pmd_unshare(mm, vma, address, ptep)) { + + ptl = hugetlb_pte_lock(&hpte); + if (hugetlb_pte_size(&hpte) == psize && + huge_pmd_unshare(mm, vma, address, hpte.ptep)) { /* * When uffd-wp is enabled on the vma, unshare * shouldn't happen at all. Warn about it if it * happened due to some reason. */ WARN_ON_ONCE(uffd_wp || uffd_wp_resolve); - pages++; + base_pages += psize / PAGE_SIZE; spin_unlock(ptl); shared_pmd = true; - address |= last_addr_mask; + address = (address | last_addr_mask) + psize; continue; } - pte = huge_ptep_get(ptep); + pte = huge_ptep_get(hpte.ptep); if (unlikely(is_hugetlb_entry_hwpoisoned(pte))) { /* Nothing to do. */ } else if (unlikely(is_hugetlb_entry_migration(pte))) { @@ -6861,7 +6863,7 @@ unsigned long hugetlb_change_protection(struct vm_area_struct *vma, entry = make_readable_migration_entry( swp_offset(entry)); newpte = swp_entry_to_pte(entry); - pages++; + base_pages += hugetlb_pte_size(&hpte) / PAGE_SIZE; } if (uffd_wp) @@ -6869,34 +6871,49 @@ unsigned long hugetlb_change_protection(struct vm_area_struct *vma, else if (uffd_wp_resolve) newpte = pte_swp_clear_uffd_wp(newpte); if (!pte_same(pte, newpte)) - set_huge_pte_at(mm, address, ptep, newpte); + set_huge_pte_at(mm, address, hpte.ptep, newpte); } else if (unlikely(is_pte_marker(pte))) { /* No other markers apply for now. */ WARN_ON_ONCE(!pte_marker_uffd_wp(pte)); if (uffd_wp_resolve) /* Safe to modify directly (non-present->none). */ - huge_pte_clear(mm, address, ptep, psize); + huge_pte_clear(mm, address, hpte.ptep, + hugetlb_pte_size(&hpte)); } else if (!huge_pte_none(pte)) { pte_t old_pte; - unsigned int shift = huge_page_shift(hstate_vma(vma)); + unsigned int shift = hpte.shift; - old_pte = huge_ptep_modify_prot_start(vma, address, ptep); + if (unlikely(!hugetlb_pte_present_leaf(&hpte, pte))) { + /* + * Someone split the PTE from under us, so retry + * the walk, + */ + spin_unlock(ptl); + continue; + } + + old_pte = huge_ptep_modify_prot_start( + vma, address, hpte.ptep); pte = huge_pte_modify(old_pte, newprot); - pte = arch_make_huge_pte(pte, shift, vma->vm_flags); + pte = arch_make_huge_pte( + pte, shift, vma->vm_flags); if (uffd_wp) pte = huge_pte_mkuffd_wp(pte); else if (uffd_wp_resolve) pte = huge_pte_clear_uffd_wp(pte); - huge_ptep_modify_prot_commit(vma, address, ptep, old_pte, pte); - pages++; + huge_ptep_modify_prot_commit( + vma, address, hpte.ptep, + old_pte, pte); + base_pages += hugetlb_pte_size(&hpte) / PAGE_SIZE; } else { /* None pte */ if (unlikely(uffd_wp)) /* Safe to modify directly (none->non-present). */ - set_huge_pte_at(mm, address, ptep, + set_huge_pte_at(mm, address, hpte.ptep, make_pte_marker(PTE_MARKER_UFFD_WP)); } spin_unlock(ptl); + address += hugetlb_pte_size(&hpte); } /* * Must flush TLB before releasing i_mmap_rwsem: x86's huge_pmd_unshare @@ -6919,7 +6936,7 @@ unsigned long hugetlb_change_protection(struct vm_area_struct *vma, hugetlb_vma_unlock_write(vma); mmu_notifier_invalidate_range_end(&range); - return pages << h->order; + return base_pages; } /* Return true if reservation was successful, false otherwise. */