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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id DC70AC433EF for ; Thu, 28 Apr 2022 16:09:53 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 42ADF6B00BA; Thu, 28 Apr 2022 12:09:53 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 3B3196B00BC; Thu, 28 Apr 2022 12:09:53 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 206D28D0002; Thu, 28 Apr 2022 12:09:53 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.a.hostedemail.com [64.99.140.24]) by kanga.kvack.org (Postfix) with ESMTP id 0BB116B00BA for ; Thu, 28 Apr 2022 12:09:53 -0400 (EDT) Received: from smtpin17.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id C36812ABD0 for ; Thu, 28 Apr 2022 16:09:52 +0000 (UTC) X-FDA: 79406773824.17.428AAF7 Received: from mail-oa1-f43.google.com (mail-oa1-f43.google.com [209.85.160.43]) by imf29.hostedemail.com (Postfix) with ESMTP id 33942120071 for ; Thu, 28 Apr 2022 16:09:49 +0000 (UTC) Received: by mail-oa1-f43.google.com with SMTP id 586e51a60fabf-e68392d626so5612269fac.4 for ; Thu, 28 Apr 2022 09:09:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=nT3t1w9TRCQTEHgFchj44IQlb1iT4EUgGpNoU9tkFsY=; b=gA7bjoCxWh92i/S1XF1eE2xn7QiKAkHhFHKC43aWKcdA7yJ14+7dncrlZhI9vRwUtl YLGV3y+wPDFF0sEqS5Cgc+enP8aoQiEjLPJjxtl3Y24SUc7qkk49DVu0/eOkKfmI/9gw C+2BgS5naRu3SyMowsXtMoq9pcj6EfDXWlvq2vG4g9FP8oiIKH3pKZPqCXTgW02KHwIj ZIMSTHHal5Wv0FGwumWUpnCfiR8FXVo49X2A/juFdw+e7XwNNmxppSxiCX349+WFviEh hgUNacOjrrUsyDGWLqjyfzKSvC2YUqPnJbB2zzwsRdQ0Rm70wcFwy9obpXs1zerbYO70 /jcQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=nT3t1w9TRCQTEHgFchj44IQlb1iT4EUgGpNoU9tkFsY=; b=DgGuJUYqAWKM6O/YAYVgOhnujXpHaHllNHFyTc391XB5gjMrobdALUwSf6oylGDRnv lhVDqZleaFzCZ6qaxS5gfy0+eKq/TZktCyYzt57z2P+OYCbejn40VgU0YX+omuYCLfZ2 rOwU2KGXguwWshkn69BhU3VzuG9+ff3xxCFhko6jaurBcS+eLoWadQfcX9V1bC3Gzxqj L4VFB98g8ULijLGspwaUL9dw4Iify8v+obN24fVkeL5L74ivJl9ZF5lsdZkuZp3xfi8O MzEK5WZt4H0rES3Enj03DGZcDJh51threbOsXo2OOvRdTUTVxMxbN2BDbUbSrUORTgBt iN8A== X-Gm-Message-State: AOAM533Og39cEcRoKpTHnit+T1/TfHfEu/TrqzCAjKZLccmUC3XRQ1tY izBQEsBMIJM2Ez2DUuVZBFA= X-Google-Smtp-Source: ABdhPJy4QuxfXKo3x2RKwtWbQ7/VCsg7jnPYGdn94JBDr1/7gNQeWoBmW9i0Vii2BO1jjuiYtJxzGQ== X-Received: by 2002:a05:6870:e9a0:b0:e6:9d2:ff42 with SMTP id r32-20020a056870e9a000b000e609d2ff42mr14411601oao.7.1651162191312; Thu, 28 Apr 2022 09:09:51 -0700 (PDT) Received: from server.roeck-us.net ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id bt30-20020a0568201a9e00b0035ea84682b9sm181981oob.45.2022.04.28.09.09.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 28 Apr 2022 09:09:50 -0700 (PDT) Date: Thu, 28 Apr 2022 09:09:49 -0700 From: Guenter Roeck To: Liam Howlett Cc: "maple-tree@lists.infradead.org" , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , Andrew Morton , Yu Zhao Subject: Re: [PATCH v8 23/70] mm/mmap: change do_brk_flags() to expand existing VMA and add do_brk_munmap() Message-ID: <20220428160949.GA2923383@roeck-us.net> References: <20220426150616.3937571-1-Liam.Howlett@oracle.com> <20220426150616.3937571-24-Liam.Howlett@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220426150616.3937571-24-Liam.Howlett@oracle.com> Authentication-Results: imf29.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=gA7bjoCx; spf=pass (imf29.hostedemail.com: domain of groeck7@gmail.com designates 209.85.160.43 as permitted sender) smtp.mailfrom=groeck7@gmail.com; dmarc=none X-Rspam-User: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 33942120071 X-Stat-Signature: y8agp6otf91be6nqw6en3y59cp6jcebn X-HE-Tag: 1651162189-764589 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Apr 26, 2022 at 03:06:35PM +0000, Liam Howlett wrote: > From: "Liam R. Howlett" > > Avoid allocating a new VMA when it a vma modification can occur. When a > brk() can expand or contract a VMA, then the single store operation will > only modify one index of the maple tree instead of causing a node to split > or coalesce. This avoids unnecessary allocations/frees of maple tree > nodes and VMAs. > > Move some limit & flag verifications out of the do_brk_flags() function to > use only relevant checks in the code path of bkr() and vm_brk_flags(). > > Set the vma to check if it can expand in vm_brk_flags() if extra criteria > are met. > > Drop userfaultfd from do_brk_flags() path and only use it in > vm_brk_flags() path since that is the only place a munmap will happen. > > Signed-off-by: Liam R. Howlett This patch results in boot failures on alpha. Trying to revert it results in conflicts, so I was unable to cross-check. Bisect log attached. The failure is silent - boot simply stalls after "random: crng init done", so attaching a boot log doesn't add value. Guenter --- # bad: [bdc61aad77faf67187525028f1f355eff3849f22] Add linux-next specific files for 20220428 # good: [af2d861d4cd2a4da5137f795ee3509e6f944a25b] Linux 5.18-rc4 git bisect start 'HEAD' 'v5.18-rc4' # good: [a6ffa4aa7e81a54632f3370f4c93fce603160192] Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/cryptodev-2.6.git git bisect good a6ffa4aa7e81a54632f3370f4c93fce603160192 # good: [cd63f17e3bb63006f9f88bf7f5947b8e1601bcd9] Merge branch 'edac-for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras.git git bisect good cd63f17e3bb63006f9f88bf7f5947b8e1601bcd9 # good: [cee7bbed3e5cc089b5c364ac8ad4a186c2a28bb6] Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine.git git bisect good cee7bbed3e5cc089b5c364ac8ad4a186c2a28bb6 # good: [d5a23156ea99f10b584221893a6a7d6f6554cde8] Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab.git git bisect good d5a23156ea99f10b584221893a6a7d6f6554cde8 # good: [2f1fde90d983bc404503100c9c4bbbf1e191bcf4] selftests: cgroup: fix alloc_anon_noexit() instantly freeing memory git bisect good 2f1fde90d983bc404503100c9c4bbbf1e191bcf4 # good: [fca1db6ff251278c532231552e840c7dc36dfa76] Merge branch 'bitmap-for-next' of https://github.com/norov/linux.git git bisect good fca1db6ff251278c532231552e840c7dc36dfa76 # bad: [40b39116fe8e6fb66e3166ea40138eec506dfd91] perf: use VMA iterator git bisect bad 40b39116fe8e6fb66e3166ea40138eec506dfd91 # good: [3f2187cf9b93a58343dd01273afdab9df04b0ca3] proc: remove VMA rbtree use from nommu git bisect good 3f2187cf9b93a58343dd01273afdab9df04b0ca3 # bad: [7dbf1873ad5953d8cf732d5fd5a94c1b95c022b0] parisc: remove mmap linked list from cache handling git bisect bad 7dbf1873ad5953d8cf732d5fd5a94c1b95c022b0 # bad: [c6e0b59766907a73be6cb77683f3ba60d0115495] mm/mmap: use advanced maple tree API for mmap_region() git bisect bad c6e0b59766907a73be6cb77683f3ba60d0115495 # good: [f461d9862fdab8e6aea51094e7286f3ec1b25402] mm: optimize find_exact_vma() to use vma_lookup() git bisect good f461d9862fdab8e6aea51094e7286f3ec1b25402 # bad: [c19a5ccbcbc6fe2c422fd85b22b40abed96c6f6b] mm/mmap: change do_brk_flags() to expand existing VMA and add do_brk_munmap() git bisect bad c19a5ccbcbc6fe2c422fd85b22b40abed96c6f6b # good: [993adc76c4d7afb40133be90333b5303b02115b6] mm/khugepaged: optimize collapse_pte_mapped_thp() by using vma_lookup() git bisect good 993adc76c4d7afb40133be90333b5303b02115b6 # first bad commit: [c19a5ccbcbc6fe2c422fd85b22b40abed96c6f6b] mm/mmap: change do_brk_flags() to expand existing VMA and add do_brk_munmap()