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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 84F35C433F5 for ; Fri, 30 Sep 2022 23:10:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231248AbiI3XKF (ORCPT ); Fri, 30 Sep 2022 19:10:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45078 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230152AbiI3XKB (ORCPT ); Fri, 30 Sep 2022 19:10:01 -0400 Received: from mail-pj1-x1032.google.com (mail-pj1-x1032.google.com [IPv6:2607:f8b0:4864:20::1032]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CC15F491DF for ; Fri, 30 Sep 2022 16:09:58 -0700 (PDT) Received: by mail-pj1-x1032.google.com with SMTP id gf8so2914087pjb.5 for ; Fri, 30 Sep 2022 16:09:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date; bh=Z4pwa9gyuRqjS+eeSbjJShInrhr7/HchgUX3g2MI7Qo=; b=01waiXwd4MZZ3LxATVL4IG9OwNkJnPrCk6JCJfUK6fYGRGtzxqTn80VoU4hkFv5Bvj tSDZXiVqNe/DfdolbG41gqqxsKHSkdPeDtbNirtpDDbQBgewyvQyx/p8il0/gl6YLHV6 2P9sxjONLCnqVVU1NlApiEDi6364RosQmn+8cKQMnqHIOF0Vd+s/HGwmG9DAiuUq1G+z K1Bj/0xD69fu+X+CnSbrhW/cKk1+t3KKs40AraRyErM/yQmcMHzdEOnkiGBTMYWc51h9 oMFtVbwqRzZre/YbhLC4lL5q3pZPgOCrOLcg9/diNqio32s3NwQ2n+wz6jf/C3N6/Zy5 kawA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date; bh=Z4pwa9gyuRqjS+eeSbjJShInrhr7/HchgUX3g2MI7Qo=; b=wxUkJJrN7cV4nGIYJoYVL57zrAtS3E/IQd6HtRo/7G3KoEFzrwB4PNFFGUrUvCrHN5 CgPm43uM0X+gmwpiD+n1rAnnGSEe/PswzjKbcY0tjaKMe2l6eTi3dYbRMHnBKY38+yRp jZn5S45fgYdxbBX3qBzSbeiRYoDscR0UGrYHE2sbTy3unl5QGzmi02Lqr4KQl5E4Zkig n6HQpwDnwFyj7Wfpm0m0iiLaf/1KQ9tmT9WYlGCpbJA6LKzo05sWegWvQIFGzwzCpXUE amq5AQQOCUkTgLv9deVqcWeMu5VRUdgRNm78fIvYlh+2vFmcIF4pFEW4CgIcdGUqYsKD cOQQ== X-Gm-Message-State: ACrzQf1xhoy8xBh0NOZaoapYlWUqYcso5A/LzMGyg1J6opCsfkZPcVXk HIK9/5tFF+ywBQ9spZ3biYTt4Q== X-Google-Smtp-Source: AMsMyM4TdHJBditr2nIJON4fzX9DhjVKj8xdWhyvXPRvQd0oWhWzm/OKUm1lhy3laeebjv0gu19+kw== X-Received: by 2002:a17:903:1c5:b0:178:44cd:e9c with SMTP id e5-20020a17090301c500b0017844cd0e9cmr11481864plh.132.1664579398319; Fri, 30 Sep 2022 16:09:58 -0700 (PDT) Received: from [10.4.189.225] ([139.177.225.254]) by smtp.gmail.com with ESMTPSA id m13-20020a65564d000000b00442c70b659esm1261782pgs.91.2022.09.30.16.09.53 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 30 Sep 2022 16:09:57 -0700 (PDT) Message-ID: <1a679784-542f-1ab7-7ba8-3d560c264479@bytedance.com> Date: Sat, 1 Oct 2022 07:09:50 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:102.0) Gecko/20100101 Thunderbird/102.3.0 Subject: Re: [PATCH v3 1/2] mm: use update_mmu_tlb() on the second thread Content-Language: en-US To: Andrew Morton Cc: David Hildenbrand , maobibo@loongson.cn, chenhuacai@loongson.cn, songmuchun@bytedance.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, loongarch@lists.linux.dev, chris@zankel.net, jcmvbkbc@gmail.com References: <20220929112318.32393-1-zhengqi.arch@bytedance.com> <20220929112318.32393-2-zhengqi.arch@bytedance.com> <0fecbcdc-7324-2d76-8452-b60b4638d074@redhat.com> <32a53a8f-f6f8-6efc-a5f6-a004ffab8c99@bytedance.com> <673e494c-eb91-470a-026b-59e414d0916e@redhat.com> <20220930153135.164240eadc71ddf94d8200fb@linux-foundation.org> From: Qi Zheng In-Reply-To: <20220930153135.164240eadc71ddf94d8200fb@linux-foundation.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2022/10/1 06:31, Andrew Morton wrote: > On Fri, 30 Sep 2022 10:44:21 +0200 David Hildenbrand wrote: > >>> Oh, this is better. Hi Andrew, do I need to resend the v4? >>> >> >> I assume he can squash it, most probably no need to resend. :) > > > From: Qi Zheng > Subject: mm: use update_mmu_tlb() on the second thread > Date: Thu, 29 Sep 2022 19:23:17 +0800 > > As message in commit 7df676974359 ("mm/memory.c: Update local TLB if PTE > entry exists") said, we should update local TLB only on the second thread. > So in the do_anonymous_page() here, we should use update_mmu_tlb() > instead of update_mmu_cache() on the second thread. > > As David pointed out, this is a performance improvement, not a > correctness fix. > > Link: https://lkml.kernel.org/r/20220929112318.32393-2-zhengqi.arch@bytedance.com > Signed-off-by: Qi Zheng > Reviewed-by: Muchun Song > Acked-by: David Hildenbrand > Cc: Bibo Mao > Cc: Chris Zankel > Cc: Huacai Chen > Cc: Max Filippov > Signed-off-by: Andrew Morton > --- > > mm/memory.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > --- a/mm/memory.c~mm-use-update_mmu_tlb-on-the-second-thread > +++ a/mm/memory.c > @@ -4136,7 +4136,7 @@ static vm_fault_t do_anonymous_page(stru > vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd, vmf->address, > &vmf->ptl); > if (!pte_none(*vmf->pte)) { > - update_mmu_cache(vma, vmf->address, vmf->pte); > + update_mmu_tlb(vma, vmf->address, vmf->pte); > goto release; > } > > _ Thank you very much! :) > -- Thanks, Qi