From patchwork Mon Nov 27 10:32:34 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrea Parri X-Patchwork-Id: 170076 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:ce62:0:b0:403:3b70:6f57 with SMTP id o2csp2992795vqx; Mon, 27 Nov 2023 02:33:00 -0800 (PST) X-Google-Smtp-Source: AGHT+IEcolzlX5WWfklRnGBa4/mukk78SwZaFftQHXSW8W6aR/W9kV27PTd+id+KcjEjxupD8Qga X-Received: by 2002:a17:90b:4a8c:b0:285:b8d2:cad4 with SMTP id lp12-20020a17090b4a8c00b00285b8d2cad4mr3376190pjb.17.1701081179835; Mon, 27 Nov 2023 02:32:59 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1701081179; cv=none; d=google.com; s=arc-20160816; b=DnJt2cINrNdZDxXR6sk7B8c6Tlfirt2/VWK6usvyp8GqmBOvlrwJb2dkcSui3LlFGI kbTQnzpY+1C3veNgTQp+qffaTwZ83OWQ3g2LHqjG+yptCsqHkzH18z4daRm01W+UGjlq 4uLLqEPC3K2twkHRFIh0XU4c+UCu7SiUS1u2QBuY4jZh3sb6JdQ2QAbAkWR2sJ8lUc4q O3hO8QLIZTuRrm15XPWlOMYzRp7Yv8IUwqWFgGTBjTAQ2ILYVK8Jul10eFLLTJYZmDwr M3LXUJbYV4gmkRB/nTikJfMzPDz5O9YBYiGjt4P6Z9DH2W9IKKlTfZ27F9QXAd9jFH8x EGzw== 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 :dkim-signature; bh=dIxf4qA9d3iQNURLT0XW05wJYozIZ97sH6EQJwhq5Vo=; fh=6I8UF0n155JlUMKXPHZEdVXaDDfdWw9idVSmXg1+KEE=; b=NDCKpNoZzZWpMihz0DH9dzlUHqTXyQVYZUX7D1bAw+yCWlrhjYEiUFVLDM4E7wMXzX 0h5wJ38/FgILgihY/DYovMIEUKuz6R+fzJOa7HFSm1SzqPGLc6tzkTUzu33bVUc73XB9 1/NsG9KoNLhgs45uXvmrZuzJzjORh1J+Tf1iy9pFXhmn2WXBdviT9mcJ9g69NZX47lJY qwNyd0wRRHDEOTGhEkXx3iqnyeWk/0f5qbMUigtmweCMflW9yl2BMsllv1yzlV+dqg0j rn0VWCZWRUWNuCaVgclm6MfmFufkn/hecGn4cdOBgXNNcFOms2/V0I9aA62K8h7adKV7 /gWA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@gmail.com header.s=20230601 header.b=mNG2haVO; 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=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: from agentk.vger.email (agentk.vger.email. [23.128.96.32]) by mx.google.com with ESMTPS id u11-20020a17090ae00b00b00280414d7a6bsi9339623pjy.190.2023.11.27.02.32.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 27 Nov 2023 02:32:59 -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; dkim=pass header.i=@gmail.com header.s=20230601 header.b=mNG2haVO; 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=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by agentk.vger.email (Postfix) with ESMTP id 1AD23805ED3F; Mon, 27 Nov 2023 02:32:57 -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 S232941AbjK0Kcr (ORCPT + 99 others); Mon, 27 Nov 2023 05:32:47 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35660 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232973AbjK0Kcm (ORCPT ); Mon, 27 Nov 2023 05:32:42 -0500 Received: from mail-ed1-x529.google.com (mail-ed1-x529.google.com [IPv6:2a00:1450:4864:20::529]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0C0F4EA for ; Mon, 27 Nov 2023 02:32:49 -0800 (PST) Received: by mail-ed1-x529.google.com with SMTP id 4fb4d7f45d1cf-54b532b261bso1353393a12.1 for ; Mon, 27 Nov 2023 02:32:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1701081167; x=1701685967; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=dIxf4qA9d3iQNURLT0XW05wJYozIZ97sH6EQJwhq5Vo=; b=mNG2haVOEUMCQtqqVzdu9hpGrP0xLDGnnmMTfKE9GOZADNqDr9c2Q9Xn6jxrTSSt0D SGcX2cocuCivDt+J+9MUiBIOf6pKCrtFiLdpz4I9dS4h1xE5OQpkjqbU5ihocYCkHGRz AmT26epBajAFq1rqoud622iTgJpwXh0pPELJMUeGAHf03PfGJjh4QAN7YKgE+IUKvCed tO4RWspeMNNHmGx74a1cio1Lt6ihRf0b+Aq1wKWexH7U7Cl35s7+LcAXqQaeutw/suH9 ox8Swo4g6Qy4TNQDRtGJWUJb3TyTGyYiVGEEAvmsnXQEdxBaes9UJS6oVaLm2fnFJcqC NMAw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1701081167; x=1701685967; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=dIxf4qA9d3iQNURLT0XW05wJYozIZ97sH6EQJwhq5Vo=; b=s6nbrBAsMCAD6VJO+GrtArBehDYACZi48NBSQPX/zRAKLlZQL8ti45Fy6ipvx4M66Q cU1DWwaoWovX4aPWBDipAjPdEJM1J7Axub5ftSicn0gAHaPG3N0XwNYEzLFC18Z4r6Bw jtZ6+Y3jtK52kKLMEaJOxtfdc1fBxyzNIKQshuSsebZUPGVTCkNPrkmUMLk4YWXe5xYE tXnC7MdgnzCw6L5EDLp7eqECQYcLVvR3u0uwzASQjoM42lzM5S9WAcIHHO0P1ryvWkcA YgfriW5mKPN3XoLAuu3suWHJc1ZU/x+FPU6xboovuc7cthrlnNQP3g5Q2vd9Vj7CHWB0 uckw== X-Gm-Message-State: AOJu0Yzz4+1LR8dI5CC1HhzhTPh8rKl2ucuv8JeAjQOfV+TPaeldQljp GVgGXMHVYjQa8+K4CUHR7mw= X-Received: by 2002:a05:6402:751:b0:54b:3edc:180 with SMTP id p17-20020a056402075100b0054b3edc0180mr3517112edy.11.1701081167489; Mon, 27 Nov 2023 02:32:47 -0800 (PST) Received: from andrea.wind3.hub ([31.189.63.178]) by smtp.gmail.com with ESMTPSA id p5-20020a056402044500b00540ea3a25e6sm5142057edw.72.2023.11.27.02.32.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 27 Nov 2023 02:32:47 -0800 (PST) From: Andrea Parri To: mathieu.desnoyers@efficios.com, paulmck@kernel.org, palmer@dabbelt.com, paul.walmsley@sifive.com, aou@eecs.berkeley.edu Cc: mmaas@google.com, hboehm@google.com, striker@us.ibm.com, charlie@rivosinc.com, rehn@rivosinc.com, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Andrea Parri Subject: [PATCH 1/2] locking: Introduce prepare_sync_core_cmd() Date: Mon, 27 Nov 2023 11:32:34 +0100 Message-Id: <20231127103235.28442-2-parri.andrea@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231127103235.28442-1-parri.andrea@gmail.com> References: <20231127103235.28442-1-parri.andrea@gmail.com> MIME-Version: 1.0 X-Spam-Status: No, score=-0.6 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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]); Mon, 27 Nov 2023 02:32:57 -0800 (PST) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1783712899297389675 X-GMAIL-MSGID: 1783712899297389675 Introduce an architecture function that architectures can use to set up ("prepare") SYNC_CORE commands. The function will be used by RISC-V to update its "deferred icache- flush" data structures (icache_stale_mask). Architectures defining prepare_sync_core_cmd() static inline need to select ARCH_HAS_PREPARE_SYNC_CORE_CMD. Signed-off-by: Andrea Parri Suggested-by: Mathieu Desnoyers Reviewed-by: Mathieu Desnoyers --- include/linux/sync_core.h | 16 +++++++++++++++- init/Kconfig | 3 +++ kernel/sched/membarrier.c | 1 + 3 files changed, 19 insertions(+), 1 deletion(-) diff --git a/include/linux/sync_core.h b/include/linux/sync_core.h index 013da4b8b3272..67bb9794b8758 100644 --- a/include/linux/sync_core.h +++ b/include/linux/sync_core.h @@ -17,5 +17,19 @@ static inline void sync_core_before_usermode(void) } #endif -#endif /* _LINUX_SYNC_CORE_H */ +#ifdef CONFIG_ARCH_HAS_PREPARE_SYNC_CORE_CMD +#include +#else +/* + * This is a dummy prepare_sync_core_cmd() implementation that can be used on + * all architectures which provide unconditional core serializing instructions + * in switch_mm(). + * If your architecture doesn't provide such core serializing instructions in + * switch_mm(), you may need to write your own functions. + */ +static inline void prepare_sync_core_cmd(struct mm_struct *mm) +{ +} +#endif +#endif /* _LINUX_SYNC_CORE_H */ diff --git a/init/Kconfig b/init/Kconfig index 9ffb103fc927b..87daf50838f02 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1972,6 +1972,9 @@ source "kernel/Kconfig.locks" config ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE bool +config ARCH_HAS_PREPARE_SYNC_CORE_CMD + bool + config ARCH_HAS_SYNC_CORE_BEFORE_USERMODE bool diff --git a/kernel/sched/membarrier.c b/kernel/sched/membarrier.c index 2ad881d07752c..58f801e013988 100644 --- a/kernel/sched/membarrier.c +++ b/kernel/sched/membarrier.c @@ -320,6 +320,7 @@ static int membarrier_private_expedited(int flags, int cpu_id) MEMBARRIER_STATE_PRIVATE_EXPEDITED_SYNC_CORE_READY)) return -EPERM; ipi_func = ipi_sync_core; + prepare_sync_core_cmd(mm); } else if (flags == MEMBARRIER_FLAG_RSEQ) { if (!IS_ENABLED(CONFIG_RSEQ)) return -EINVAL; From patchwork Mon Nov 27 10:32:35 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrea Parri X-Patchwork-Id: 170077 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:ce62:0:b0:403:3b70:6f57 with SMTP id o2csp2992820vqx; Mon, 27 Nov 2023 02:33:03 -0800 (PST) X-Google-Smtp-Source: AGHT+IFhdxVdmThGZ5j53EXqP9KVlWkVE5RPdFgjBKCENVeyQHmLLn9Pcn21P7p/LWEQG1SLvhL+ X-Received: by 2002:a17:903:11d1:b0:1cc:5db8:7eb1 with SMTP id q17-20020a17090311d100b001cc5db87eb1mr13816942plh.51.1701081183375; Mon, 27 Nov 2023 02:33:03 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1701081183; cv=none; d=google.com; s=arc-20160816; b=WNWr6IOrod/Cj4mEEgGPMi1/h1M8evMhIVPQGns3nbJmDZX6A/N1nMBoXZoFVLY9ve 8biYvea1G+s2SxpPcdESQi/lC4nXa6uOs2BblQSe1nnJeD1yMY4qeYjfwyzrC3gv7NHR N8SGMnKkp8XJnVm4tNDh2RKNiJp3aGOiOsD8VXMe9xrMtCUmQ/nlW+IBern6o9zGtRPk 41gWWhuT47pozDSUwWGNRpZMjSWZPme2fMBnDI756hWnLfk2zGXCQaou+2OOLgDr8TKN 6LscjdbuiTaNODXHhbKnqpzA+UUUmj1TvpNFD8AYBIoLrww4mzQzv6BxSkIZB0Py38c1 8tUg== 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 :dkim-signature; bh=MlWvEkOns6bxM9iRll9a5EQf2qEz96P+1R1KRbDkkn8=; fh=6I8UF0n155JlUMKXPHZEdVXaDDfdWw9idVSmXg1+KEE=; b=VCddTmKDTzIRoAXk1v/rCdZrOSSq5/y3tMNYwDvZpjD2ZSk9VN1mQr+Hr+Ubp0MAZw 3Fj1Bj+2aQ0Y4lwvdbBLhYqYGANiIMN8Ahe8A93de/kd70ZztVRTyboj+urHYzDp+eAQ Z2M31SlYpeevXGKsUwlGCP6yCvEUO15C46DYKKOlxlPQdvQSKoA4219nxB+J0/lZoSc1 o26ETfBb8xGgLCHi90TzLyMowKLJfkYp1zW2aZup0zizpZwRgnDdsumaTGAUm4gEFcSN +Dx1L3rK0lVHA/nQ/ZYq7SifYn0Sfg3GDFdf6QS8iDfznKgohj7Vjp68wMSYyh9cs/fG qsOg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@gmail.com header.s=20230601 header.b=iPsOo0xf; 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=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: from snail.vger.email (snail.vger.email. [23.128.96.37]) by mx.google.com with ESMTPS id h9-20020a170902748900b001cfba7c561fsi4169241pll.249.2023.11.27.02.33.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 27 Nov 2023 02:33:03 -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; dkim=pass header.i=@gmail.com header.s=20230601 header.b=iPsOo0xf; 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=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by snail.vger.email (Postfix) with ESMTP id B1EA58092D8B; Mon, 27 Nov 2023 02:33:01 -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 S233067AbjK0Kcv (ORCPT + 99 others); Mon, 27 Nov 2023 05:32:51 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35724 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233057AbjK0Kcp (ORCPT ); Mon, 27 Nov 2023 05:32:45 -0500 Received: from mail-lf1-x136.google.com (mail-lf1-x136.google.com [IPv6:2a00:1450:4864:20::136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AB5FDE1 for ; Mon, 27 Nov 2023 02:32:51 -0800 (PST) Received: by mail-lf1-x136.google.com with SMTP id 2adb3069b0e04-50aab20e828so5764250e87.2 for ; Mon, 27 Nov 2023 02:32:51 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1701081170; x=1701685970; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=MlWvEkOns6bxM9iRll9a5EQf2qEz96P+1R1KRbDkkn8=; b=iPsOo0xfotl+oYMGstYFj+BqF+SaRQTvd9D8SFWpGP62fwk9yKjPzLh9N6aO+sc39K CWIFsjQksqwr6OU7fNO65lMcMqdikApBWfTggDuzsM5x9g6jnctuKQ2isbMPhI34r+bl Q5cPnGJ6zXfGE0Y3A/QgznQE8DHQj2d81jM0trXjCpnUvdGOiQKPmqlZdBDr9T3uoNj0 HV3k3IeJ8ai+k94DAn9cWFUqntRzTlsFC7OTVyXAZh6ntJc/a8oX6yshKBWSSBKNSrqj eCNwJO1Ae/iiHJJ7NdX1+8G2INd4621oWtcq3HcwzIt0hcLzGfqJrt26O9T79/7m3MNt Qzkg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1701081170; x=1701685970; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=MlWvEkOns6bxM9iRll9a5EQf2qEz96P+1R1KRbDkkn8=; b=SOpqElASBSCwe0x+2Cm/Jdv7/2r+3aWjB+OKMukATiqQxUirU6iDUNxPMksP8o2+kY ztW9Zie0G5e0e9z2sEXfUZ3VFeBM493Q95vrKz1x4VdHvGUMgxvWzLRDgrZXqIgKrIql CH6k+aApv/EVoVetDMXbk11JDpKgQm6jYUQFgEx7K4dlpU81LZZR+bPuE8aHxa747toT wLrMreTW0Lgv1/ZmUjIfm6c3AzXVIbEWahLrAEEoEU/kyO7Baw4P0Vi3FF3mqA3SfU25 F6Gs6F8j/yqPh3Z+lAbeYxuJ4i5ZCqh2RTKkTFXtlAz0A9lJ2hy+aSyffKYDZ59ZejNn lYZQ== X-Gm-Message-State: AOJu0YzOUVIaWlIu4+VMRMXz0pP7dFkif9h35azzsgFgJpUid868SUn/ GCZ99CR3fnBPFx1eFGZFBc8= X-Received: by 2002:a05:6512:3903:b0:500:9f7b:e6a4 with SMTP id a3-20020a056512390300b005009f7be6a4mr5841895lfu.32.1701081169590; Mon, 27 Nov 2023 02:32:49 -0800 (PST) Received: from andrea.wind3.hub ([31.189.63.178]) by smtp.gmail.com with ESMTPSA id p5-20020a056402044500b00540ea3a25e6sm5142057edw.72.2023.11.27.02.32.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 27 Nov 2023 02:32:49 -0800 (PST) From: Andrea Parri To: mathieu.desnoyers@efficios.com, paulmck@kernel.org, palmer@dabbelt.com, paul.walmsley@sifive.com, aou@eecs.berkeley.edu Cc: mmaas@google.com, hboehm@google.com, striker@us.ibm.com, charlie@rivosinc.com, rehn@rivosinc.com, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Andrea Parri Subject: [PATCH 2/2] membarrier: riscv: Provide core serializing command Date: Mon, 27 Nov 2023 11:32:35 +0100 Message-Id: <20231127103235.28442-3-parri.andrea@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231127103235.28442-1-parri.andrea@gmail.com> References: <20231127103235.28442-1-parri.andrea@gmail.com> MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM, RCVD_IN_DNSWL_BLOCKED,SPF_HELO_NONE,SPF_PASS,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]); Mon, 27 Nov 2023 02:33:01 -0800 (PST) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1783712896511671914 X-GMAIL-MSGID: 1783712902831856673 RISC-V uses xRET instructions on return from interrupt and to go back to user-space; the xRET instruction is not core serializing. Use FENCE.I for providing core serialization as follows: - by calling sync_core_before_usermode() on return from interrupt (cf. ipi_sync_core()), - via switch_mm() and sync_core_before_usermode() (respectively, for uthread->uthread and kthread->uthread transitions) to go back to user-space. On RISC-V, the serialization in switch_mm() is activated by resetting the icache_stale_mask of the mm at prepare_sync_core_cmd(). Signed-off-by: Andrea Parri Suggested-by: Palmer Dabbelt --- .../membarrier-sync-core/arch-support.txt | 2 +- arch/riscv/Kconfig | 3 ++ arch/riscv/include/asm/sync_core.h | 29 +++++++++++++++++++ 3 files changed, 33 insertions(+), 1 deletion(-) create mode 100644 arch/riscv/include/asm/sync_core.h diff --git a/Documentation/features/sched/membarrier-sync-core/arch-support.txt b/Documentation/features/sched/membarrier-sync-core/arch-support.txt index d96b778b87ed8..f6f0bd871a578 100644 --- a/Documentation/features/sched/membarrier-sync-core/arch-support.txt +++ b/Documentation/features/sched/membarrier-sync-core/arch-support.txt @@ -43,7 +43,7 @@ | openrisc: | TODO | | parisc: | TODO | | powerpc: | ok | - | riscv: | TODO | + | riscv: | ok | | s390: | ok | | sh: | TODO | | sparc: | TODO | diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 95a2a06acc6a6..3e2734a3f2957 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -27,14 +27,17 @@ config RISCV select ARCH_HAS_GCOV_PROFILE_ALL select ARCH_HAS_GIGANTIC_PAGE select ARCH_HAS_KCOV + select ARCH_HAS_MEMBARRIER_SYNC_CORE select ARCH_HAS_MMIOWB select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE select ARCH_HAS_PMEM_API + select ARCH_HAS_PREPARE_SYNC_CORE_CMD select ARCH_HAS_PTE_SPECIAL select ARCH_HAS_SET_DIRECT_MAP if MMU select ARCH_HAS_SET_MEMORY if MMU select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL select ARCH_HAS_STRICT_MODULE_RWX if MMU && !XIP_KERNEL + select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE select ARCH_HAS_SYSCALL_WRAPPER select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST select ARCH_HAS_UBSAN_SANITIZE_ALL diff --git a/arch/riscv/include/asm/sync_core.h b/arch/riscv/include/asm/sync_core.h new file mode 100644 index 0000000000000..9153016da8f14 --- /dev/null +++ b/arch/riscv/include/asm/sync_core.h @@ -0,0 +1,29 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_RISCV_SYNC_CORE_H +#define _ASM_RISCV_SYNC_CORE_H + +/* + * RISC-V implements return to user-space through an xRET instruction, + * which is not core serializing. + */ +static inline void sync_core_before_usermode(void) +{ + asm volatile ("fence.i" ::: "memory"); +} + +#ifdef CONFIG_SMP +/* + * Ensure the next switch_mm() on every CPU issues a core serializing + * instruction for the given @mm. + */ +static inline void prepare_sync_core_cmd(struct mm_struct *mm) +{ + cpumask_setall(&mm->context.icache_stale_mask); +} +#else +static inline void prepare_sync_core_cmd(struct mm_struct *mm) +{ +} +#endif /* CONFIG_SMP */ + +#endif /* _ASM_RISCV_SYNC_CORE_H */