From patchwork Mon Apr 10 13:43:51 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yicong Yang X-Patchwork-Id: 13206384 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id EAB37C77B70 for ; Mon, 10 Apr 2023 13:45:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=BVb8bTYMCfo0MHIKALS0KdWXFRl/0k8Jn4i8VgQwDZQ=; b=qVgDup5Fli+LA9 5hzfypCmOPYF7OJhhW0Gr869p0rXl/l0heM19B22jPlK+OdtXrQMWsYCWA+Nf18aJ/6S4rcXbUCMT 5KnRcuoQOY7L03ujJ89bebi0qtkb72ZtZlgi2v6DIPe/41AqixTqUX2sdaZs9boIbxs4eJ5Jia7o8 FaZt89X1GaSpG83aGurwcQ9ooJ6uSAhBVe2NeLNQMUgCJ1OwHsYW1UVMkcHySRC0XncydeMxaMTtt K9gVXvxFEXS5eV83Aoc+L1WHWy5BSUO3cM6dF2S4bXUwm/+6lC2pcT6F5VL9oFeJt8YW8cOIXvIfO T88YRahBVPlr7Kl0NQVw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1plrpF-00FJEB-0w; Mon, 10 Apr 2023 13:44:53 +0000 Received: from szxga08-in.huawei.com ([45.249.212.255]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1plrp9-00FJ9h-09; Mon, 10 Apr 2023 13:44:49 +0000 Received: from canpemm500009.china.huawei.com (unknown [172.30.72.56]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4Pw99M0wYdz17RLS; Mon, 10 Apr 2023 21:41:11 +0800 (CST) Received: from localhost.localdomain (10.50.163.32) by canpemm500009.china.huawei.com (7.192.105.203) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.23; Mon, 10 Apr 2023 21:44:42 +0800 From: Yicong Yang To: , , , , , , , CC: , , , , , , , , , , , , , , , , , Barry Song <21cnbao@gmail.com>, , , , , Anshuman Khandual , Barry Song Subject: [PATCH v9 1/2] mm/tlbbatch: Introduce arch_tlbbatch_should_defer() Date: Mon, 10 Apr 2023 21:43:51 +0800 Message-ID: <20230410134352.4519-2-yangyicong@huawei.com> X-Mailer: git-send-email 2.31.0 In-Reply-To: <20230410134352.4519-1-yangyicong@huawei.com> References: <20230410134352.4519-1-yangyicong@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.50.163.32] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To canpemm500009.china.huawei.com (7.192.105.203) X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230410_064448_124243_321A8BA4 X-CRM114-Status: GOOD ( 10.62 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Anshuman Khandual The entire scheme of deferred TLB flush in reclaim path rests on the fact that the cost to refill TLB entries is less than flushing out individual entries by sending IPI to remote CPUs. But architecture can have different ways to evaluate that. Hence apart from checking TTU_BATCH_FLUSH in the TTU flags, rest of the decision should be architecture specific. Signed-off-by: Anshuman Khandual [https://lore.kernel.org/linuxppc-dev/20171101101735.2318-2-khandual@linux.vnet.ibm.com/] Signed-off-by: Yicong Yang [Rebase and fix incorrect return value type] Reviewed-by: Kefeng Wang Reviewed-by: Anshuman Khandual Reviewed-by: Barry Song Reviewed-by: Xin Hao Tested-by: Punit Agrawal --- arch/x86/include/asm/tlbflush.h | 12 ++++++++++++ mm/rmap.c | 9 +-------- 2 files changed, 13 insertions(+), 8 deletions(-) diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h index cda3118f3b27..8a497d902c16 100644 --- a/arch/x86/include/asm/tlbflush.h +++ b/arch/x86/include/asm/tlbflush.h @@ -240,6 +240,18 @@ static inline void flush_tlb_page(struct vm_area_struct *vma, unsigned long a) flush_tlb_mm_range(vma->vm_mm, a, a + PAGE_SIZE, PAGE_SHIFT, false); } +static inline bool arch_tlbbatch_should_defer(struct mm_struct *mm) +{ + bool should_defer = false; + + /* If remote CPUs need to be flushed then defer batch the flush */ + if (cpumask_any_but(mm_cpumask(mm), get_cpu()) < nr_cpu_ids) + should_defer = true; + put_cpu(); + + return should_defer; +} + static inline u64 inc_mm_tlb_gen(struct mm_struct *mm) { /* diff --git a/mm/rmap.c b/mm/rmap.c index 8632e02661ac..38ccb700748c 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -686,17 +686,10 @@ static void set_tlb_ubc_flush_pending(struct mm_struct *mm, bool writable) */ static bool should_defer_flush(struct mm_struct *mm, enum ttu_flags flags) { - bool should_defer = false; - if (!(flags & TTU_BATCH_FLUSH)) return false; - /* If remote CPUs need to be flushed then defer batch the flush */ - if (cpumask_any_but(mm_cpumask(mm), get_cpu()) < nr_cpu_ids) - should_defer = true; - put_cpu(); - - return should_defer; + return arch_tlbbatch_should_defer(mm); } /*