From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CF781C433E9 for ; Sun, 31 Jan 2021 00:16:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A522B64E1A for ; Sun, 31 Jan 2021 00:16:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232493AbhAaAQn (ORCPT ); Sat, 30 Jan 2021 19:16:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50160 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232164AbhAaAQ1 (ORCPT ); Sat, 30 Jan 2021 19:16:27 -0500 Received: from mail-pg1-x52f.google.com (mail-pg1-x52f.google.com [IPv6:2607:f8b0:4864:20::52f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3CEC3C061574 for ; Sat, 30 Jan 2021 16:16:02 -0800 (PST) Received: by mail-pg1-x52f.google.com with SMTP id c132so9446057pga.3 for ; Sat, 30 Jan 2021 16:16:02 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=l25hYkMVDoyooYvVfTs7fc3Z+gKHwtM6S7f1RS+25jI=; b=QWgShbAGwg3wKINOtZylfbSTrKZ7qLVxJ9N5IFviem4ZQZbvt3Qb5FGnEFjaJkKWM8 +N59D/2HoNthkC9KM8y5rri2hSwYvZ3PGjWAtGVOTbVKPODJHb+bNvA2CTILAtcpT2eF h2vKj7f18D9utR+WqRIZocdX9KGJMGNpGDq4OAUv3clGITiSokZvfotFKb0au2qJk83H +vQ3E86+C/gXHYcrJ616SNR0zQDCLX573HjZiqIKyq8Skylj6hd55xtbGDdaDulme6bC qkMuGVJdrJXN1VfTQjQkLNTiMdo9yVwgsqXAzyKwt97zZNMt7qYeioV6GYWPf1kFGeIf 5v9A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=l25hYkMVDoyooYvVfTs7fc3Z+gKHwtM6S7f1RS+25jI=; b=BWVNtrlXpm+zy9HHrFqgviLJWdpL88OggdsgLfNLheOaw+Ocnq1Ay0wIMpP/cxalXw hfVHgHoRIuBuiBz/H1D30RVtg5a1Qqp83YOgBmzPZwwDZFTsBcqfe4B16F88GgEmHhg2 WhhYiuaapRwFYCqpEYdjL/87O8H+domBIXRcnKX4oPUCLLjG9oBq/dBQBS59JMjCihiA 0oqbxw1HXyeZ+sNSBG28ecsPsiJ8lgFa5haowXjN2ho+GivaRMTxBi+cf2Mz1ResvtIN PyhkxLrES3tt5+0OT0cuERt5uxS3u2nKT4ut8xIKetnECihIca4ygErbDuo6ECH52sLz 7wCg== X-Gm-Message-State: AOAM530uMQtRyZ5ZUpEfNO9SuWFrl8+lPl3YowyMLVfkXQtcGVrdmR6L jaKdjLd07UutXauqi3NouIQ= X-Google-Smtp-Source: ABdhPJyd6V4GPxAmmHG/IDX8wnqgvmExjPww3NvYNxqdzTjwzAadbhjaaR3aAin7oAYPZWEG51FDXg== X-Received: by 2002:a63:c148:: with SMTP id p8mr10395437pgi.188.1612052161728; Sat, 30 Jan 2021 16:16:01 -0800 (PST) Received: from sc2-haas01-esx0118.eng.vmware.com ([66.170.99.1]) by smtp.gmail.com with ESMTPSA id e12sm13127365pga.13.2021.01.30.16.16.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 30 Jan 2021 16:16:01 -0800 (PST) From: Nadav Amit X-Google-Original-From: Nadav Amit To: linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: Nadav Amit , Andrea Arcangeli , Andrew Morton , Andy Lutomirski , Dave Hansen , Peter Zijlstra , Thomas Gleixner , Will Deacon , Yu Zhao , Nick Piggin , x86@kernel.org Subject: [RFC 01/20] mm/tlb: fix fullmm semantics Date: Sat, 30 Jan 2021 16:11:13 -0800 Message-Id: <20210131001132.3368247-2-namit@vmware.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210131001132.3368247-1-namit@vmware.com> References: <20210131001132.3368247-1-namit@vmware.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Nadav Amit fullmm in mmu_gather is supposed to indicate that the mm is torn-down (e.g., on process exit) and can therefore allow certain optimizations. However, tlb_finish_mmu() sets fullmm, when in fact it want to say that the TLB should be fully flushed. Change tlb_finish_mmu() to set need_flush_all and check this flag in tlb_flush_mmu_tlbonly() when deciding whether a flush is needed. Signed-off-by: Nadav Amit Cc: Andrea Arcangeli Cc: Andrew Morton Cc: Andy Lutomirski Cc: Dave Hansen Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Will Deacon Cc: Yu Zhao Cc: Nick Piggin Cc: x86@kernel.org --- include/asm-generic/tlb.h | 2 +- mm/mmu_gather.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/include/asm-generic/tlb.h b/include/asm-generic/tlb.h index 2c68a545ffa7..eea113323468 100644 --- a/include/asm-generic/tlb.h +++ b/include/asm-generic/tlb.h @@ -420,7 +420,7 @@ static inline void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb) * these bits. */ if (!(tlb->freed_tables || tlb->cleared_ptes || tlb->cleared_pmds || - tlb->cleared_puds || tlb->cleared_p4ds)) + tlb->cleared_puds || tlb->cleared_p4ds || tlb->need_flush_all)) return; tlb_flush(tlb); diff --git a/mm/mmu_gather.c b/mm/mmu_gather.c index 0dc7149b0c61..5a659d4e59eb 100644 --- a/mm/mmu_gather.c +++ b/mm/mmu_gather.c @@ -323,7 +323,7 @@ void tlb_finish_mmu(struct mmu_gather *tlb) * On x86 non-fullmm doesn't yield significant difference * against fullmm. */ - tlb->fullmm = 1; + tlb->need_flush_all = 1; __tlb_reset_range(tlb); tlb->freed_tables = 1; } -- 2.25.1