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 1E84EC02180 for ; Wed, 15 Jan 2025 21:46:30 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A8D096B007B; Wed, 15 Jan 2025 16:46:29 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id A3D216B0082; Wed, 15 Jan 2025 16:46:29 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8DD316B0085; Wed, 15 Jan 2025 16:46:29 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 6F2846B007B for ; Wed, 15 Jan 2025 16:46:29 -0500 (EST) Received: from smtpin18.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 01AC11A0343 for ; Wed, 15 Jan 2025 21:46:28 +0000 (UTC) X-FDA: 83011020498.18.56EC47C Received: from mail-qt1-f170.google.com (mail-qt1-f170.google.com [209.85.160.170]) by imf08.hostedemail.com (Postfix) with ESMTP id 1D07C16001C for ; Wed, 15 Jan 2025 21:46:26 +0000 (UTC) Authentication-Results: imf08.hostedemail.com; dkim=pass header.d=google.com header.s=20230601 header.b=wcYZCJ2J; spf=pass (imf08.hostedemail.com: domain of surenb@google.com designates 209.85.160.170 as permitted sender) smtp.mailfrom=surenb@google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1736977587; 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=kG/IausjT1eOPJpJpSmaWqXdjNmS2nF45sOMWzC8YfA=; b=4hRdhVIMDu4O6BKLcQ2jPYA6pHwrSwvWhvQ0/DkFK6gpCx2bkPOeSQQCuGPWNYHVWXs1lm GkLJKOOgAUo7MD2iR1OWfGQ5kzNViTyWHNturBw7IHoDjUQqOidfdeWos4kfz9inRVOWXE 4+7VdfnxnemlrYR+vXZUN5jkSh0/+Lc= ARC-Authentication-Results: i=1; imf08.hostedemail.com; dkim=pass header.d=google.com header.s=20230601 header.b=wcYZCJ2J; spf=pass (imf08.hostedemail.com: domain of surenb@google.com designates 209.85.160.170 as permitted sender) smtp.mailfrom=surenb@google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1736977587; a=rsa-sha256; cv=none; b=GE5TIb2ZZ1XRLvK3k83lNctcTO586XqgxtZm7pGwtcwKfC1jWl/1VZ+d/WYfI9CEOn8DE9 jWXbJ+Vis+Pw49Ox2k8qTVmstkoHBV8EUItvulbCKjz17U8UIpM4SmPrN9BMoRGRfnU6DR fuQKiPRCFzZlHUiUaOBexjg48gNIUUg= Received: by mail-qt1-f170.google.com with SMTP id d75a77b69052e-467896541e1so61491cf.0 for ; Wed, 15 Jan 2025 13:46:26 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1736977586; x=1737582386; darn=kvack.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=kG/IausjT1eOPJpJpSmaWqXdjNmS2nF45sOMWzC8YfA=; b=wcYZCJ2J/zDxUV99ak4fr8nmGoNMAWoeG92zgSeRT00TLayfv26Eazgt8waHhtjY74 RCdn/yTItWY/s74IaiUiUr5Ik6IFgSg8CIVyA6itGhs4UXaHDETEpBZAy11JXFQFS2dh bF9Y4eA0xWJfFWLyDkOZ8WJ6nUt7HFxoxOaJAyQen1dY86MRI6hlFsWUOxb14RQJGLsZ /KmE13Bsvb2q3IonNyXT4AxKjecH0E4wg1IpmipNJnwz6ho5BZAvxCBkkk9SGR74TPzq ml1ksSoJUO54/+SGlCbd3q10+4Um3I9A8Pvaf7U5UOMJwG9huBn7ikPxbub57EqHzUx0 1taA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1736977586; x=1737582386; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=kG/IausjT1eOPJpJpSmaWqXdjNmS2nF45sOMWzC8YfA=; b=eHOZCGTlJCevN5vrpfidC1lrS2esaL+eWg33SvGd6+W82M+JlkDjBcZ0DF8F7tqvF4 RKzbCFOBDOkoQgWVo4W0XdfSNNQCUuwhx1ZrEdtwJrad1b87YWuti9r+6rBlqZ/TO8Fn 9gb5vaW3y+BKic3aTTwUJ95+yB3eCxYNu9H3lqmkoj9gsHSuG4rReplVpO/PLrcSDcEu KolIbqTObTXyWxDDb+jUlu7By9LAeJOoU6Bw6MxhoGQKu0iJo6hbbUoCmqJPTZgX+rsM qAfvnH7AfGyuOLhmvn+Tps01isL9sPTxSBudc8UIj0+bT+jdoiHffjXlfKBB+5qh7QkL uDOw== X-Forwarded-Encrypted: i=1; AJvYcCUx23iZ1CmBc4fjHEOe4X1+C1dLdxFGXxNYMZw63BrQeHMdiFZzg68tnVy+PClZch4YxzrdmLEbUA==@kvack.org X-Gm-Message-State: AOJu0YwLVJUlrQbZIk5y2XVPTvteKHm3qZ7v9HpmddeU8rkKvadE2ScI 2Oze3BUqIh748kOJZbTl5QnOnYj2Srxsl05ODkgvUw08OvoeLRBgC2HBHfKwOTN8lmD9SwboVlO JPhh4O/wKC54Q/Y3QtQZRJLFfaGOiLr3MH/BF X-Gm-Gg: ASbGncuCdGvmyYfWuyKGovvUAZ0klU4pMTsBpIgf4EmpMeCKTI/a88Vqei1v0C6+2Gw RJDEaBa29ECn2XpfZ9uoYsPmE23VEMNCBPyGJigH1qnrtpI9iSjK4Ixz2yTfMXXgat0E= X-Google-Smtp-Source: AGHT+IFE1Zown3D3qGPwAAJZHA33xl0d59VJvU2bb7jFRbeQNvKPpdPNS9ZSkNetglibCOVY9W52Aa5UIbolNqm9vkE= X-Received: by 2002:a05:622a:178b:b0:46d:f29d:4173 with SMTP id d75a77b69052e-46e04186a53mr989191cf.16.1736977585910; Wed, 15 Jan 2025 13:46:25 -0800 (PST) MIME-Version: 1.0 References: <20250111042604.3230628-1-surenb@google.com> <20250111042604.3230628-17-surenb@google.com> <20250115022703.hqbqdqawvqgrfgxb@master> <20250115121729.al7sxmpqutmhaxod@master> In-Reply-To: <20250115121729.al7sxmpqutmhaxod@master> From: Suren Baghdasaryan Date: Wed, 15 Jan 2025 13:46:14 -0800 X-Gm-Features: AbW1kva--QFLsx6XOwxGB9xKaHXReW5_CE0WTclZ5S6s_fvXChfK4C4r2avyMvI Message-ID: Subject: Re: [PATCH v9 16/17] mm: make vma cache SLAB_TYPESAFE_BY_RCU To: Wei Yang Cc: akpm@linux-foundation.org, peterz@infradead.org, willy@infradead.org, liam.howlett@oracle.com, lorenzo.stoakes@oracle.com, david.laight.linux@gmail.com, mhocko@suse.com, vbabka@suse.cz, 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, corbet@lwn.net, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-team@android.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: 1D07C16001C X-Rspam-User: X-Rspamd-Server: rspam11 X-Stat-Signature: ywjp5wbsqtbbgeq445i783t599y5epam X-HE-Tag: 1736977586-328719 X-HE-Meta: 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 YUmuEah8 Dg93Ig61zgszMWyMGbhiyWVjxxg0SAU1+hEHJXehsuKYKv0K6ZT1hJ+GGnt7jhskPYJVPGP2BgWHXlvQNK3fUKRucPko+w9MyHfSKZ651fM1RQkVIV8W+rHXQKlhqFaOBEenB+X4IvSH0UehOCyCyuc1jMeO1U4qSggLgzVdS65Gf26PxJMgq1WVimMY7Nq1uvn5esf4gXenIOiC8/jbz54a5ElTGeVHG/kf+zz8/YO4RnCLOr2Z4IccCntVshyfyC/f8vrPMQbOz/RDQYzkbW+Fgme8WKxal91aBgMPg5vhhZsu9sOKEnmnxhOk3dNcAgD0L+WlI2OgYy0gdJlqBeeKNSQ== 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: List-Subscribe: List-Unsubscribe: On Wed, Jan 15, 2025 at 4:17=E2=80=AFAM Wei Yang wrote: > > On Tue, Jan 14, 2025 at 07:15:05PM -0800, Suren Baghdasaryan wrote: > >On Tue, Jan 14, 2025 at 6:27=E2=80=AFPM Wei Yang wrote: > >> > >> On Fri, Jan 10, 2025 at 08:26:03PM -0800, Suren Baghdasaryan wrote: > >> > >> >diff --git a/kernel/fork.c b/kernel/fork.c > >> >index 9d9275783cf8..151b40627c14 100644 > >> >--- a/kernel/fork.c > >> >+++ b/kernel/fork.c > >> >@@ -449,6 +449,42 @@ struct vm_area_struct *vm_area_alloc(struct mm_s= truct *mm) > >> > return vma; > >> > } > >> > > >> >+static void vm_area_init_from(const struct vm_area_struct *src, > >> >+ struct vm_area_struct *dest) > >> >+{ > >> >+ dest->vm_mm =3D src->vm_mm; > >> >+ dest->vm_ops =3D src->vm_ops; > >> >+ dest->vm_start =3D src->vm_start; > >> >+ dest->vm_end =3D src->vm_end; > >> >+ dest->anon_vma =3D src->anon_vma; > >> >+ dest->vm_pgoff =3D src->vm_pgoff; > >> >+ dest->vm_file =3D src->vm_file; > >> >+ dest->vm_private_data =3D src->vm_private_data; > >> >+ vm_flags_init(dest, src->vm_flags); > >> >+ memcpy(&dest->vm_page_prot, &src->vm_page_prot, > >> >+ sizeof(dest->vm_page_prot)); > >> >+ /* > >> >+ * src->shared.rb may be modified concurrently when called fro= m > >> >+ * dup_mmap(), but the clone will reinitialize it. > >> >+ */ > >> >+ data_race(memcpy(&dest->shared, &src->shared, sizeof(dest->sha= red))); > >> >+ memcpy(&dest->vm_userfaultfd_ctx, &src->vm_userfaultfd_ctx, > >> >+ sizeof(dest->vm_userfaultfd_ctx)); > >> >+#ifdef CONFIG_ANON_VMA_NAME > >> >+ dest->anon_name =3D src->anon_name; > >> >+#endif > >> >+#ifdef CONFIG_SWAP > >> >+ memcpy(&dest->swap_readahead_info, &src->swap_readahead_info, > >> >+ sizeof(dest->swap_readahead_info)); > >> >+#endif > >> >+#ifndef CONFIG_MMU > >> >+ dest->vm_region =3D src->vm_region; > >> >+#endif > >> >+#ifdef CONFIG_NUMA > >> >+ dest->vm_policy =3D src->vm_policy; > >> >+#endif > >> >+} > >> > >> Would this be difficult to maintain? We should make sure not miss or o= verwrite > >> anything. > > > >Yeah, it is less maintainable than a simple memcpy() but I did not > >find a better alternative. I added a warning above the struct > >vm_area_struct definition to update this function every time we change > >that structure. Not sure if there is anything else I can do to help > >with this. > > > > For !PER_VMA_LOCK, maybe we can use memcpy() as usual. > > For PER_VMA_LOCK, I just come up the same idea with you:-) Missed this comment. Yeah, in one of the previous versions I had different !PER_VMA_LOCK and PER_VMA_LOCK versions of vma_copy() but David raised a question whether it is worth having two versions. From performance POV there is no reason for that and it unnecessarily complicates the code. So, I dropped that in favor of having one version. > > >> > >> -- > >> Wei Yang > >> Help you, Help me > > -- > Wei Yang > Help you, Help me