From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="BhZjDEmW" Received: from mail-wr1-x434.google.com (mail-wr1-x434.google.com [IPv6:2a00:1450:4864:20::434]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 87C1DB7; Sun, 19 Nov 2023 23:41:47 -0800 (PST) Received: by mail-wr1-x434.google.com with SMTP id ffacd0b85a97d-32fd7fc9f19so2671575f8f.2; Sun, 19 Nov 2023 23:41:47 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1700466106; x=1701070906; darn=vger.kernel.org; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date:from:to :cc:subject:date:message-id:reply-to; bh=UcnRCn9RBtyZwzYZjL7Mal3df0TOYaoALw3ajoI8ruo=; b=BhZjDEmWA6rMhy2zRLDgfrKFAF8a/S/0etGDujI+e4o+gnbFdJPTUaqIY6ZnnC/B30 TeI4s+w4PXARxXrma6rn9lLXI/mggcJHvq6m8DRQgJ9csaGCgzDnQjLx4a8SvTw6muwf q5HZOe4asiYuZflkKWeKhTZsoSwO5fnMoIiKci2SqpEd71J+smJw0ltd56BvTNk98XdT DiLuiOgegCreNJJU1F8T56KVn1Mr4VQbwWfTEAEICGi3Jv+pZhXkp2sHesE1wJPd6w3J IaS5KU+x49OeJ92wQm+lv39uwnD3XrP+/v4eyJaCmBvoGhOHx1igMi8TTYuteO3BGri8 55cQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1700466106; x=1701070906; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=UcnRCn9RBtyZwzYZjL7Mal3df0TOYaoALw3ajoI8ruo=; b=owbAUT75hoLH873t3p7i22kikH65MPqktXNGW0ZnRGYpcYXCEV7G5+oriFcMKpCbjA hkZ1Fpq2XFE1EqpQOZkCcpiC+/QWTz9Hj6dBwUXW2bj8ZJWfwEx5p5c/5u2evFd9R7h6 UGuyOTeITPMP2DYe2ByQKjgeWMM6TC11fIOGYASESQJVFeD7jUe30Zk/b6qoJ7cHcCEc tOOARoy4ceO/ICAa3er1RwOlvPiYQz7fqkMGkXqc8+r8uRNog6yp5Vp9DglOQkepmG1e Ho3TJ5PtFi40raDrfiw0TtZGzawNPsUjVACGHZOoWeOy+GEy+7VDzXre3IUQxNM9Smfh ImUA== X-Gm-Message-State: AOJu0YzF1SiOipm9gnwkkyvm9TDvSaO6TWcCJOTZVUaNIVlwtA0yZ+up JsSU/8J0PueXQ6C9JhO33IlvnGB7WFMctA== X-Google-Smtp-Source: AGHT+IGLxhKtp3IKpPAJiweTS4UYRDByB4GjdiKC0IaFf2a6rUb8Hh+cAbWkEb3mZscgg4QSavm/EA== X-Received: by 2002:a5d:48c9:0:b0:331:6ad3:853 with SMTP id p9-20020a5d48c9000000b003316ad30853mr3683767wrs.41.1700466105720; Sun, 19 Nov 2023 23:41:45 -0800 (PST) Received: from f (cst-prg-3-109.cust.vodafone.cz. [46.135.3.109]) by smtp.gmail.com with ESMTPSA id i13-20020a5d55cd000000b003313426f136sm10142299wrw.39.2023.11.19.23.41.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 19 Nov 2023 23:41:45 -0800 (PST) Date: Mon, 20 Nov 2023 08:41:06 +0100 From: Mateusz Guzik To: kernel test robot Cc: Christian Brauner , oe-lkp@lists.linux.dev, lkp@intel.com, linux-kernel@vger.kernel.org, Jann Horn , Linus Torvalds , linux-doc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, intel-gfx@lists.freedesktop.org, linux-fsdevel@vger.kernel.org, gfs2@lists.linux.dev, bpf@vger.kernel.org, ying.huang@intel.com, feng.tang@intel.com, fengwei.yin@intel.com Subject: Re: [linus:master] [file] 0ede61d858: will-it-scale.per_thread_ops -2.9% regression Message-ID: References: <202311201406.2022ca3f-oliver.sang@intel.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <202311201406.2022ca3f-oliver.sang@intel.com> On Mon, Nov 20, 2023 at 03:11:31PM +0800, kernel test robot wrote: > > > Hello, > > kernel test robot noticed a -2.9% regression of will-it-scale.per_thread_ops on: > > > commit: 0ede61d8589cc2d93aa78230d74ac58b5b8d0244 ("file: convert to SLAB_TYPESAFE_BY_RCU") > https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master > > 93faf426e3cc000c 0ede61d8589cc2d93aa78230d74 > ---------------- --------------------------- > %stddev %change %stddev > \ | \ [snip] > 30.90 ± 4% -20.6 10.35 ± 2% perf-profile.self.cycles-pp.__fget_light > 0.00 +26.5 26.48 perf-profile.self.cycles-pp.__get_file_rcu [snip] So __fget_light now got a func call. I don't know if this is worth patching (and benchmarking after), but I if sorting this out is of interest, triviality below is probably the easiest way out: diff --git a/fs/file.c b/fs/file.c index 5fb0b146e79e..d8d3e18800c4 100644 --- a/fs/file.c +++ b/fs/file.c @@ -856,14 +856,14 @@ void do_close_on_exec(struct files_struct *files) spin_unlock(&files->file_lock); } -static struct file *__get_file_rcu(struct file __rcu **f) +static __always_inline struct file *__get_file_rcu(struct file __rcu **f) { struct file __rcu *file; struct file __rcu *file_reloaded; struct file __rcu *file_reloaded_cmp; file = rcu_dereference_raw(*f); - if (!file) + if (unlikely(!file)) return NULL; if (unlikely(!atomic_long_inc_not_zero(&file->f_count))) @@ -891,7 +891,7 @@ static struct file *__get_file_rcu(struct file __rcu **f) * If the pointers don't match the file has been reallocated by * SLAB_TYPESAFE_BY_RCU. */ - if (file == file_reloaded_cmp) + if (likely(file == file_reloaded_cmp)) return file_reloaded; fput(file); 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 0AE0DC4167B for ; Mon, 27 Nov 2023 14:35:36 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A315C10E2DA; Mon, 27 Nov 2023 14:35:31 +0000 (UTC) Received: from mail-wr1-x42e.google.com (mail-wr1-x42e.google.com [IPv6:2a00:1450:4864:20::42e]) by gabe.freedesktop.org (Postfix) with ESMTPS id 957E410E140 for ; Mon, 20 Nov 2023 07:41:47 +0000 (UTC) Received: by mail-wr1-x42e.google.com with SMTP id ffacd0b85a97d-332c46d5988so555612f8f.1 for ; Sun, 19 Nov 2023 23:41:47 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1700466106; x=1701070906; darn=lists.freedesktop.org; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date:from:to :cc:subject:date:message-id:reply-to; bh=UcnRCn9RBtyZwzYZjL7Mal3df0TOYaoALw3ajoI8ruo=; b=LFXow9VCsmp2GoWni2XeKg/V5nwkTeYkPZk1qJYuqMnSKDsDlVfG/5KzTo7bU/PvJh pSLvHgSjVqWff6sSnq6pUZLtX0rFZUDfUI1EeCxN7gt5OpBW/umNQogwM8zyv+8gSn9S nU3IHcPK0ONPLavYO1Q6uxebxjZctE5M2eN5TGH92bwu6hNjr2v7jLsoxdz93TASc36I fQ10l2s1wLSojvnbidRn6tb4x8byJ40dP9yMv6OF922ZbO89T1gU1MnckXIDF79u69ds EkIzKcY8rMWWRrXQhbRqgZxj+7GnXYQpVDPbB2ZOOli45ybKh8uzylZPSSVdn0q26Z71 /xIQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1700466106; x=1701070906; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=UcnRCn9RBtyZwzYZjL7Mal3df0TOYaoALw3ajoI8ruo=; b=Pn85fBLwTcmJPk/4TPWKvMl2bDFv+kK79IIXatMCg17/+qYu0KcQhd9ppv05UoIx+Z Gf9xcjWcfYCVo+W0c5TQ0mRD2Yr/fFhuopn6IQp6bFAJwzKoaU2Yhf9e/fGqa61HkzWF vSFgnZVGPHmGNcxIovbHCYlJ4WFQ/Z6Vm36Ea0ocWVFnFHk/6tfSkKvh4aS1OHxfyXPQ ROuJEU3u+xKSw7kht1XR5HIDcyVBUtgjadmlo5qzaE9PjaQfXxfpgKNlzy/O8ErKSN6z F93U8l2p5/Wf7c8h4LegQhdklb9TRiwEPko2spB6mrJh8KUVoY+iSrj+Aq0sL7xWKwXO eAzg== X-Gm-Message-State: AOJu0Yx74B4OBbJjFPOG40YsdHJyRvKvDpTGuqisWg/G3IImSp/OrTKw mcwmjd+FQtxgSYTi1HWie2Y= X-Google-Smtp-Source: AGHT+IGLxhKtp3IKpPAJiweTS4UYRDByB4GjdiKC0IaFf2a6rUb8Hh+cAbWkEb3mZscgg4QSavm/EA== X-Received: by 2002:a5d:48c9:0:b0:331:6ad3:853 with SMTP id p9-20020a5d48c9000000b003316ad30853mr3683767wrs.41.1700466105720; Sun, 19 Nov 2023 23:41:45 -0800 (PST) Received: from f (cst-prg-3-109.cust.vodafone.cz. [46.135.3.109]) by smtp.gmail.com with ESMTPSA id i13-20020a5d55cd000000b003313426f136sm10142299wrw.39.2023.11.19.23.41.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 19 Nov 2023 23:41:45 -0800 (PST) Date: Mon, 20 Nov 2023 08:41:06 +0100 From: Mateusz Guzik To: kernel test robot Message-ID: References: <202311201406.2022ca3f-oliver.sang@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <202311201406.2022ca3f-oliver.sang@intel.com> X-Mailman-Approved-At: Mon, 27 Nov 2023 14:35:29 +0000 Subject: Re: [Intel-gfx] [linus:master] [file] 0ede61d858: will-it-scale.per_thread_ops -2.9% regression X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Christian Brauner , Jann Horn , linuxppc-dev@lists.ozlabs.org, intel-gfx@lists.freedesktop.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, fengwei.yin@intel.com, gfs2@lists.linux.dev, linux-fsdevel@vger.kernel.org, feng.tang@intel.com, ying.huang@intel.com, oe-lkp@lists.linux.dev, bpf@vger.kernel.org, Linus Torvalds Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Mon, Nov 20, 2023 at 03:11:31PM +0800, kernel test robot wrote: > > > Hello, > > kernel test robot noticed a -2.9% regression of will-it-scale.per_thread_ops on: > > > commit: 0ede61d8589cc2d93aa78230d74ac58b5b8d0244 ("file: convert to SLAB_TYPESAFE_BY_RCU") > https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master > > 93faf426e3cc000c 0ede61d8589cc2d93aa78230d74 > ---------------- --------------------------- > %stddev %change %stddev > \ | \ [snip] > 30.90 ± 4% -20.6 10.35 ± 2% perf-profile.self.cycles-pp.__fget_light > 0.00 +26.5 26.48 perf-profile.self.cycles-pp.__get_file_rcu [snip] So __fget_light now got a func call. I don't know if this is worth patching (and benchmarking after), but I if sorting this out is of interest, triviality below is probably the easiest way out: diff --git a/fs/file.c b/fs/file.c index 5fb0b146e79e..d8d3e18800c4 100644 --- a/fs/file.c +++ b/fs/file.c @@ -856,14 +856,14 @@ void do_close_on_exec(struct files_struct *files) spin_unlock(&files->file_lock); } -static struct file *__get_file_rcu(struct file __rcu **f) +static __always_inline struct file *__get_file_rcu(struct file __rcu **f) { struct file __rcu *file; struct file __rcu *file_reloaded; struct file __rcu *file_reloaded_cmp; file = rcu_dereference_raw(*f); - if (!file) + if (unlikely(!file)) return NULL; if (unlikely(!atomic_long_inc_not_zero(&file->f_count))) @@ -891,7 +891,7 @@ static struct file *__get_file_rcu(struct file __rcu **f) * If the pointers don't match the file has been reallocated by * SLAB_TYPESAFE_BY_RCU. */ - if (file == file_reloaded_cmp) + if (likely(file == file_reloaded_cmp)) return file_reloaded; fput(file); 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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (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 80578C54FB9 for ; Mon, 20 Nov 2023 07:42:51 +0000 (UTC) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20230601 header.b=h2XjvTAP; dkim-atps=neutral Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4SYfcT6M56z3cgg for ; Mon, 20 Nov 2023 18:42:49 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20230601 header.b=h2XjvTAP; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=gmail.com (client-ip=2a00:1450:4864:20::436; helo=mail-wr1-x436.google.com; envelope-from=mjguzik@gmail.com; receiver=lists.ozlabs.org) Received: from mail-wr1-x436.google.com (mail-wr1-x436.google.com [IPv6:2a00:1450:4864:20::436]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4SYfbT63Lmz3cJW for ; Mon, 20 Nov 2023 18:41:56 +1100 (AEDT) Received: by mail-wr1-x436.google.com with SMTP id ffacd0b85a97d-32f7abbb8b4so2681550f8f.0 for ; Sun, 19 Nov 2023 23:41:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1700466106; x=1701070906; darn=lists.ozlabs.org; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date:from:to :cc:subject:date:message-id:reply-to; bh=UcnRCn9RBtyZwzYZjL7Mal3df0TOYaoALw3ajoI8ruo=; b=h2XjvTAPYGJmE+pSNGl4LAjhlFxtPMRl16C8/C2GbKdc9kOeJGrqdV38sdd7+gNEG5 bi9L9bSx6jVR7DHMED6mKpoxeAluAi/gjNbg/z5Wr36g8t9SiV0BZTsWn7wg5TdDojAl IQOTKvD9XnRUinPMs+RWTYYtkil6E4CP2etvRhOofHx+nY+JYH2HmpbpT1mXksiLckI+ /L9FW40M4gRUDFeZpTzZ/CutX0eCZqLhl5XGscuddNCM87OcJ249VK9bbSQwLKzhD3wY vOrGQueEdtEiRKuTpkUwsFpaTnR24kKWcLQYwewJ7wVmYAE7P/GPlpKqVwg63Qzl9ZKQ K3kQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1700466106; x=1701070906; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=UcnRCn9RBtyZwzYZjL7Mal3df0TOYaoALw3ajoI8ruo=; b=xUpFiCcwavTnb7lIu1SdkerIe5+VLLtsZScg4bgSheLUYDEq0rC7rexQTs8N4P30J6 8PraTfh3kSZ5CfvTDuHMuio3ARURll+RomrHBDeP89KFGwLis7yOSac/yEeOwc9mZJOo +1QcomGQhTLFaa1+Klga9C+YPeDtcDFWQZUZiIIX8e70Q8aBfwjy2r3SRUCnwkpAScRM s6gGRnBUF2GUjZ3VT7M/eoQRTEsf4tttThyeXO9oRILYZIW6hgYsDxXlhfz0h+RmzSY3 2zY0f/eWVYfGiI770nSWmo59V4xIz/1NvXiz8SJ6M5ftjlqzMWM0z+7RIqW5y+YEJATg OGjw== X-Gm-Message-State: AOJu0Yyi4/YeVEIxTrwGCLIhXArXlBpGP5o2dMTCbDkASGFNigq5Btn1 GP5xz6XPVldMbCIofriiWz0= X-Google-Smtp-Source: AGHT+IGLxhKtp3IKpPAJiweTS4UYRDByB4GjdiKC0IaFf2a6rUb8Hh+cAbWkEb3mZscgg4QSavm/EA== X-Received: by 2002:a5d:48c9:0:b0:331:6ad3:853 with SMTP id p9-20020a5d48c9000000b003316ad30853mr3683767wrs.41.1700466105720; Sun, 19 Nov 2023 23:41:45 -0800 (PST) Received: from f (cst-prg-3-109.cust.vodafone.cz. [46.135.3.109]) by smtp.gmail.com with ESMTPSA id i13-20020a5d55cd000000b003313426f136sm10142299wrw.39.2023.11.19.23.41.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 19 Nov 2023 23:41:45 -0800 (PST) Date: Mon, 20 Nov 2023 08:41:06 +0100 From: Mateusz Guzik To: kernel test robot Subject: Re: [linus:master] [file] 0ede61d858: will-it-scale.per_thread_ops -2.9% regression Message-ID: References: <202311201406.2022ca3f-oliver.sang@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <202311201406.2022ca3f-oliver.sang@intel.com> X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Christian Brauner , lkp@intel.com, Jann Horn , linuxppc-dev@lists.ozlabs.org, intel-gfx@lists.freedesktop.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, fengwei.yin@intel.com, gfs2@lists.linux.dev, linux-fsdevel@vger.kernel.org, feng.tang@intel.com, ying.huang@intel.com, oe-lkp@lists.linux.dev, bpf@vger.kernel.org, Linus Torvalds Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Mon, Nov 20, 2023 at 03:11:31PM +0800, kernel test robot wrote: > > > Hello, > > kernel test robot noticed a -2.9% regression of will-it-scale.per_thread_ops on: > > > commit: 0ede61d8589cc2d93aa78230d74ac58b5b8d0244 ("file: convert to SLAB_TYPESAFE_BY_RCU") > https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master > > 93faf426e3cc000c 0ede61d8589cc2d93aa78230d74 > ---------------- --------------------------- > %stddev %change %stddev > \ | \ [snip] > 30.90 ± 4% -20.6 10.35 ± 2% perf-profile.self.cycles-pp.__fget_light > 0.00 +26.5 26.48 perf-profile.self.cycles-pp.__get_file_rcu [snip] So __fget_light now got a func call. I don't know if this is worth patching (and benchmarking after), but I if sorting this out is of interest, triviality below is probably the easiest way out: diff --git a/fs/file.c b/fs/file.c index 5fb0b146e79e..d8d3e18800c4 100644 --- a/fs/file.c +++ b/fs/file.c @@ -856,14 +856,14 @@ void do_close_on_exec(struct files_struct *files) spin_unlock(&files->file_lock); } -static struct file *__get_file_rcu(struct file __rcu **f) +static __always_inline struct file *__get_file_rcu(struct file __rcu **f) { struct file __rcu *file; struct file __rcu *file_reloaded; struct file __rcu *file_reloaded_cmp; file = rcu_dereference_raw(*f); - if (!file) + if (unlikely(!file)) return NULL; if (unlikely(!atomic_long_inc_not_zero(&file->f_count))) @@ -891,7 +891,7 @@ static struct file *__get_file_rcu(struct file __rcu **f) * If the pointers don't match the file has been reallocated by * SLAB_TYPESAFE_BY_RCU. */ - if (file == file_reloaded_cmp) + if (likely(file == file_reloaded_cmp)) return file_reloaded; fput(file);