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 46CA2E77188 for ; Fri, 10 Jan 2025 22:14:29 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C8D2F6B00A0; Fri, 10 Jan 2025 17:14:28 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id C3BC16B00B0; Fri, 10 Jan 2025 17:14:28 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A8F456B00B1; Fri, 10 Jan 2025 17:14:28 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 897186B00A0 for ; Fri, 10 Jan 2025 17:14:28 -0500 (EST) Received: from smtpin23.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 326D1120E86 for ; Fri, 10 Jan 2025 22:14:28 +0000 (UTC) X-FDA: 82992947016.23.705A278 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.223.131]) by imf30.hostedemail.com (Postfix) with ESMTP id B1E8280014 for ; Fri, 10 Jan 2025 22:14:25 +0000 (UTC) Authentication-Results: imf30.hostedemail.com; dkim=pass header.d=suse.cz header.s=susede2_rsa header.b="Uz++8OA/"; dkim=pass header.d=suse.cz header.s=susede2_ed25519 header.b=nutB2144; dkim=pass header.d=suse.cz header.s=susede2_rsa header.b=OoIKBSBW; dkim=pass header.d=suse.cz header.s=susede2_ed25519 header.b=9Vzcdyqn; spf=pass (imf30.hostedemail.com: domain of vbabka@suse.cz designates 195.135.223.131 as permitted sender) smtp.mailfrom=vbabka@suse.cz; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1736547266; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=9fCOLrPZKmNtYtn9PSY8KZegUu8wjK4R3eSGZGp0IZ8=; b=kuO40mIg7NcygY2g7uWe7LLclvafK5Wj0p4wLp1kp3cdarATd5o1DuMe47qaOpVDTmCxqM PkHEYaMM7rnOZx2tyvYwVly2JMwALZCeC45j3hr8c5B7knIfC+Z8trozFSJmLsk5n67OcU qKt6esf6LyrbFJ2sFyMC3AKL/SnxJZU= ARC-Authentication-Results: i=1; imf30.hostedemail.com; dkim=pass header.d=suse.cz header.s=susede2_rsa header.b="Uz++8OA/"; dkim=pass header.d=suse.cz header.s=susede2_ed25519 header.b=nutB2144; dkim=pass header.d=suse.cz header.s=susede2_rsa header.b=OoIKBSBW; dkim=pass header.d=suse.cz header.s=susede2_ed25519 header.b=9Vzcdyqn; spf=pass (imf30.hostedemail.com: domain of vbabka@suse.cz designates 195.135.223.131 as permitted sender) smtp.mailfrom=vbabka@suse.cz; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1736547266; a=rsa-sha256; cv=none; b=T2sgkXeVODtvIKwU2tgTuWF/OQRmxi82GNajB3+bAXdjVbp6q9jLK6RBA8dYp3BOOfBt+H HJdGlzblUyIXdhHE95L4zqbQ9FAmYfObvTi/yCMzderOhiG+aiSNdVHQr6Zrne9zGL2UPe 9dO8FNlhafeFLFie6T4QWlhq7856ZDY= Received: from imap1.dmz-prg2.suse.org (imap1.dmz-prg2.suse.org [IPv6:2a07:de40:b281:104:10:150:64:97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id DA1111F37C; Fri, 10 Jan 2025 22:14:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1736547264; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:autocrypt:autocrypt; bh=9fCOLrPZKmNtYtn9PSY8KZegUu8wjK4R3eSGZGp0IZ8=; b=Uz++8OA/Z3v+N/USU2yJaUB+Dp6QOTIh7YpPH7M8J9CGZiU1QXZfir7N40VkVDbUmMf9dt uOw4+HKj2dsq/Hf1hJ77d2VjXQ3FHXJL67Ty1DDwkBxxou3vamhVSsLZ5nNihVuQDnvhC9 MurR/VBGGuaMSabd/suNpUERBspPlgY= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1736547264; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:autocrypt:autocrypt; bh=9fCOLrPZKmNtYtn9PSY8KZegUu8wjK4R3eSGZGp0IZ8=; b=nutB21443HQpUNvP+mheRsFd7LsQIBE/iRSwWwjhT4Usn2B2setpJzvTEJhyaM0I0xB+Rc Do2E+ZTQCmBx0fBw== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1736547263; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:autocrypt:autocrypt; bh=9fCOLrPZKmNtYtn9PSY8KZegUu8wjK4R3eSGZGp0IZ8=; b=OoIKBSBWn1SWG3G2LpDoCAyKQ5DtY2xUnk00opNYLbrATp+FhbaehMEMygATV5Q+mMVfKq iIpgEodH95byrEO3UX8gHa2b2hKY/di8GXPlbAVbZR8gmKef8LVjJkAD+7Yyrw2zxgfrup D7VvxmWQt5eTCrOcKymbckr7clYC4M8= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1736547263; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:autocrypt:autocrypt; bh=9fCOLrPZKmNtYtn9PSY8KZegUu8wjK4R3eSGZGp0IZ8=; b=9Vzcdyqn567AjNS5qM3fWPpRyJvKKhcAAXqqDmaF05ljjE4o/XJjb803Bq0GTBnQDYiTGa 5wufc09LSgBbCHAA== Received: from imap1.dmz-prg2.suse.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by imap1.dmz-prg2.suse.org (Postfix) with ESMTPS id 95EF213A86; Fri, 10 Jan 2025 22:14:23 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id GNPTI7+bgWe6dwAAD6G6ig (envelope-from ); Fri, 10 Jan 2025 22:14:23 +0000 Message-ID: <2d0029de-146b-41fe-86d3-7a3472bf3607@suse.cz> Date: Fri, 10 Jan 2025 23:14:23 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v8 15/16] mm: make vma cache SLAB_TYPESAFE_BY_RCU To: Suren Baghdasaryan Cc: akpm@linux-foundation.org, peterz@infradead.org, willy@infradead.org, liam.howlett@oracle.com, lorenzo.stoakes@oracle.com, mhocko@suse.com, hannes@cmpxchg.org, mjguzik@gmail.com, oliver.sang@intel.com, mgorman@techsingularity.net, david@redhat.com, peterx@redhat.com, oleg@redhat.com, dave@stgolabs.net, paulmck@kernel.org, brauner@kernel.org, dhowells@redhat.com, hdanton@sina.com, hughd@google.com, lokeshgidra@google.com, minchan@google.com, jannh@google.com, shakeel.butt@linux.dev, souravpanda@google.com, pasha.tatashin@soleen.com, klarasmodin@gmail.com, richard.weiyang@gmail.com, corbet@lwn.net, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-team@android.com References: <20250109023025.2242447-1-surenb@google.com> <20250109023025.2242447-16-surenb@google.com> <41ebce1a-9cc0-471e-ac20-25efea9a933a@suse.cz> Content-Language: en-US From: Vlastimil Babka Autocrypt: addr=vbabka@suse.cz; keydata= xsFNBFZdmxYBEADsw/SiUSjB0dM+vSh95UkgcHjzEVBlby/Fg+g42O7LAEkCYXi/vvq31JTB KxRWDHX0R2tgpFDXHnzZcQywawu8eSq0LxzxFNYMvtB7sV1pxYwej2qx9B75qW2plBs+7+YB 87tMFA+u+L4Z5xAzIimfLD5EKC56kJ1CsXlM8S/LHcmdD9Ctkn3trYDNnat0eoAcfPIP2OZ+ 9oe9IF/R28zmh0ifLXyJQQz5ofdj4bPf8ecEW0rhcqHfTD8k4yK0xxt3xW+6Exqp9n9bydiy tcSAw/TahjW6yrA+6JhSBv1v2tIm+itQc073zjSX8OFL51qQVzRFr7H2UQG33lw2QrvHRXqD Ot7ViKam7v0Ho9wEWiQOOZlHItOOXFphWb2yq3nzrKe45oWoSgkxKb97MVsQ+q2SYjJRBBH4 8qKhphADYxkIP6yut/eaj9ImvRUZZRi0DTc8xfnvHGTjKbJzC2xpFcY0DQbZzuwsIZ8OPJCc LM4S7mT25NE5kUTG/TKQCk922vRdGVMoLA7dIQrgXnRXtyT61sg8PG4wcfOnuWf8577aXP1x 6mzw3/jh3F+oSBHb/GcLC7mvWreJifUL2gEdssGfXhGWBo6zLS3qhgtwjay0Jl+kza1lo+Cv BB2T79D4WGdDuVa4eOrQ02TxqGN7G0Biz5ZLRSFzQSQwLn8fbwARAQABzSBWbGFzdGltaWwg QmFia2EgPHZiYWJrYUBzdXNlLmN6PsLBlAQTAQoAPgIbAwULCQgHAwUVCgkICwUWAgMBAAIe AQIXgBYhBKlA1DSZLC6OmRA9UCJPp+fMgqZkBQJkBREIBQkRadznAAoJECJPp+fMgqZkNxIQ ALZRqwdUGzqL2aeSavbum/VF/+td+nZfuH0xeWiO2w8mG0+nPd5j9ujYeHcUP1edE7uQrjOC Gs9sm8+W1xYnbClMJTsXiAV88D2btFUdU1mCXURAL9wWZ8Jsmz5ZH2V6AUszvNezsS/VIT87 AmTtj31TLDGwdxaZTSYLwAOOOtyqafOEq+gJB30RxTRE3h3G1zpO7OM9K6ysLdAlwAGYWgJJ V4JqGsQ/lyEtxxFpUCjb5Pztp7cQxhlkil0oBYHkudiG8j1U3DG8iC6rnB4yJaLphKx57NuQ PIY0Bccg+r9gIQ4XeSK2PQhdXdy3UWBr913ZQ9AI2usid3s5vabo4iBvpJNFLgUmxFnr73SJ KsRh/2OBsg1XXF/wRQGBO9vRuJUAbnaIVcmGOUogdBVS9Sun/Sy4GNA++KtFZK95U7J417/J Hub2xV6Ehc7UGW6fIvIQmzJ3zaTEfuriU1P8ayfddrAgZb25JnOW7L1zdYL8rXiezOyYZ8Fm ZyXjzWdO0RpxcUEp6GsJr11Bc4F3aae9OZtwtLL/jxc7y6pUugB00PodgnQ6CMcfR/HjXlae h2VS3zl9+tQWHu6s1R58t5BuMS2FNA58wU/IazImc/ZQA+slDBfhRDGYlExjg19UXWe/gMcl De3P1kxYPgZdGE2eZpRLIbt+rYnqQKy8UxlszsBNBFsZNTUBCACfQfpSsWJZyi+SHoRdVyX5 J6rI7okc4+b571a7RXD5UhS9dlVRVVAtrU9ANSLqPTQKGVxHrqD39XSw8hxK61pw8p90pg4G /N3iuWEvyt+t0SxDDkClnGsDyRhlUyEWYFEoBrrCizbmahOUwqkJbNMfzj5Y7n7OIJOxNRkB IBOjPdF26dMP69BwePQao1M8Acrrex9sAHYjQGyVmReRjVEtv9iG4DoTsnIR3amKVk6si4Ea X/mrapJqSCcBUVYUFH8M7bsm4CSxier5ofy8jTEa/CfvkqpKThTMCQPNZKY7hke5qEq1CBk2 wxhX48ZrJEFf1v3NuV3OimgsF2odzieNABEBAAHCwXwEGAEKACYCGwwWIQSpQNQ0mSwujpkQ PVAiT6fnzIKmZAUCZAUSmwUJDK5EZgAKCRAiT6fnzIKmZOJGEACOKABgo9wJXsbWhGWYO7mD 8R8mUyJHqbvaz+yTLnvRwfe/VwafFfDMx5GYVYzMY9TWpA8psFTKTUIIQmx2scYsRBUwm5VI EurRWKqENcDRjyo+ol59j0FViYysjQQeobXBDDE31t5SBg++veI6tXfpco/UiKEsDswL1WAr tEAZaruo7254TyH+gydURl2wJuzo/aZ7Y7PpqaODbYv727Dvm5eX64HCyyAH0s6sOCyGF5/p eIhrOn24oBf67KtdAN3H9JoFNUVTYJc1VJU3R1JtVdgwEdr+NEciEfYl0O19VpLE/PZxP4wX PWnhf5WjdoNI1Xec+RcJ5p/pSel0jnvBX8L2cmniYnmI883NhtGZsEWj++wyKiS4NranDFlA HdDM3b4lUth1pTtABKQ1YuTvehj7EfoWD3bv9kuGZGPrAeFNiHPdOT7DaXKeHpW9homgtBxj 8aX/UkSvEGJKUEbFL9cVa5tzyialGkSiZJNkWgeHe+jEcfRT6pJZOJidSCdzvJpbdJmm+eED w9XOLH1IIWh7RURU7G1iOfEfmImFeC3cbbS73LQEFGe1urxvIH5K/7vX+FkNcr9ujwWuPE9b 1C2o4i/yZPLXIVy387EjA6GZMqvQUFuSTs/GeBcv0NjIQi8867H3uLjz+mQy63fAitsDwLmR EP+ylKVEKb0Q2A== In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Action: no action X-Rspamd-Queue-Id: B1E8280014 X-Stat-Signature: aozds1etdnap334dgajzqxtjg18z6re4 X-Rspam-User: X-Rspamd-Server: rspam11 X-HE-Tag: 1736547265-625974 X-HE-Meta: U2FsdGVkX19rLzu3Xe4YXTaTRuYYJbIhQlVHp5t774Wqf5RuAY8oT6bL6mAoAzSsEoke+rDlBr55DYWFdzuHJ33jtJNnLfr+CRcVVOwqF94h3Fn9c7QymEDpAzjGAfTL90xwtIwfWcRm5Zr6kOVTqFDERQhhBvdg6THPr/YZNXSdfxL9wh9s/K5dXDOboSFkpVxY2DGHOHsvl4opbAXlaC7z9vfjcCVSbLB4lIE76kPq12EGcVm4nSNivJQvmvsd3YOb0x0wG8XgK0lkp79gK+x1EzWtz1wLHjOpKBASFVRSHL2OIXXRqGr+zgEh8SYa+mdKJdy3Emj2CbLdmxoFr1ezI+PGzKqaTHuhXfXKsqH409COUzQi7mOUhL5p95DCQp00oWaxb1547Y1fVXKZPlzrmIbXk0+w4BIaF1ic+68CPfBazbFtvnOXFtalg1aRcaPGh5a97/e8rcXkn7rsZYV+JzdOz0gFJcw3eobY5d07mSMG3A1aRFKFcqOcPb19KVexxOUQfGVcx3soRYu5b1pHIBh3iJqlfeL3TkxrDxlvVlua3sPIWJ5qcvEsvrDyyeydAKZT6d5NeYk1Al92WAoMAEG5tYbiOtsGafuqMuUsn6hc1upXP0Ijqc5z/HkfUUHWe8ATVrqdjgk0ZaOSQ+XFQ3LRo1NOqC6N4e78iEtsJ5twQaRYNYpm66uDcNES71WZYp0e6dkkX5J5Of03MH5v0ZFLeX2ky0bPzu6X0Pk4ontmT9nlK/HUvwOXv2GO9nQ/7CutTE4V0VULZECJlQn56S/UdFQIsSgkhwaWU8vAWIe4DOCunBz9HE/BPny0FjD4Ejqnw/kqQttNow9kleFiR9gLASzixtGjSze5aEO8I1o5d5SB0w96x3czKqLciV/HWsap7o0zMdHcTy9x2JJHKW34PbGJEi5XHkYkcwhvDbXLpclEsBicT5XOOfJdlcMsOTq1tc4MeQqA7SJ 8WxPBu5I CqA4bTkrZZgVf63l3iRH9IoMWHMqO/ekhPrtxT9AdVHchGQBtrDJW0AIJ4vOUfqYXeNZMpw4gPFIFGzF0wzbnlmUB4+DzNshntQjZV6+0OCMzGHQzQ1I6WBzW0YzPKvaORlJW5G3XfGgg7cF39Xv0bKFIho4xq1VGj0f+cDHA1LDZP8VTMd8R+UZ4kWqjUjdNN5OUeMowHBy/LnIXOI7Tr2Gr6A5e/UXbODzK4F5ui+5zL1Szm+VPNkR6vnGAkrYJYw00fytniH9INKXApNpxQFhAiej1nA85OlOyHiPZli874xM5jftgthlkk0wjsLTiAKKyf4tiNNrPvCAf/4o2nlZ/T3hauKmOQJdha8yn0DVrudL+c0lAhOJJzUv3GTlY7s6+UKCBk+wA5oNOaRlvJuy9sKFc83v9/cimW4KvgNz4DTPePN3+qzDjDVXX6E6EnBEF2+AuMmDe0Yc= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000027, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 1/10/25 17:07, Suren Baghdasaryan wrote: > On Fri, Jan 10, 2025 at 7:31 AM Vlastimil Babka wrote: > > I see vm_area_dup() being used in dup_mmap() and I think this comment > is about this usage in case the src vma changes from under us. > However, vm_area_dup() is also used when we simply duplicate an > existing vma while holding an mmap_write_lock, like in __split_vma(). > In these cases there is no possibility of a race and copied value > should hold. Maybe I should amend this comment like this: > > /* > * src->shared.rb may be modified concurrently when called from dup_mmap(), > * but the clone will reinitialize it. > */ > > WDYT? Sounds good, thanks! >> >>