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[46.135.71.44]) by smtp.gmail.com with ESMTPSA id 4fb4d7f45d1cf-5e4c3bb747csm8691328a12.42.2025.03.04.10.35.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 04 Mar 2025 10:35:18 -0800 (PST) From: Mateusz Guzik To: brauner@kernel.org, viro@zeniv.linux.org.uk Cc: jack@suse.cz, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Mateusz Guzik Subject: [PATCH v2 1/4] file: add fput and file_ref_put routines optimized for use when closing a fd Date: Tue, 4 Mar 2025 19:35:03 +0100 Message-ID: <20250304183506.498724-2-mjguzik@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250304183506.498724-1-mjguzik@gmail.com> References: <20250304183506.498724-1-mjguzik@gmail.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Vast majority of the time closing a file descriptor also operates on the last reference, where a regular fput usage will result in 2 atomics. This can be changed to only suffer 1. See commentary above file_ref_put_close() for more information. Signed-off-by: Mateusz Guzik --- fs/file.c | 75 ++++++++++++++++++++++++++++++---------- fs/file_table.c | 72 +++++++++++++++++++++++++++----------- include/linux/file.h | 2 ++ include/linux/file_ref.h | 1 + 4 files changed, 111 insertions(+), 39 deletions(-) diff --git a/fs/file.c b/fs/file.c index 44efdc8c1e27..ea753f9c8e08 100644 --- a/fs/file.c +++ b/fs/file.c @@ -26,6 +26,28 @@ #include "internal.h" +static bool __file_ref_put_badval(file_ref_t *ref, unsigned long cnt) +{ + /* + * If the reference count was already in the dead zone, then this + * put() operation is imbalanced. Warn, put the reference count back to + * DEAD and tell the caller to not deconstruct the object. + */ + if (WARN_ONCE(cnt >= FILE_REF_RELEASED, "imbalanced put on file reference count")) { + atomic_long_set(&ref->refcnt, FILE_REF_DEAD); + return false; + } + + /* + * This is a put() operation on a saturated refcount. Restore the + * mean saturation value and tell the caller to not deconstruct the + * object. + */ + if (cnt > FILE_REF_MAXREF) + atomic_long_set(&ref->refcnt, FILE_REF_SATURATED); + return false; +} + /** * __file_ref_put - Slowpath of file_ref_put() * @ref: Pointer to the reference count @@ -67,27 +89,44 @@ bool __file_ref_put(file_ref_t *ref, unsigned long cnt) return true; } - /* - * If the reference count was already in the dead zone, then this - * put() operation is imbalanced. Warn, put the reference count back to - * DEAD and tell the caller to not deconstruct the object. - */ - if (WARN_ONCE(cnt >= FILE_REF_RELEASED, "imbalanced put on file reference count")) { - atomic_long_set(&ref->refcnt, FILE_REF_DEAD); - return false; - } - - /* - * This is a put() operation on a saturated refcount. Restore the - * mean saturation value and tell the caller to not deconstruct the - * object. - */ - if (cnt > FILE_REF_MAXREF) - atomic_long_set(&ref->refcnt, FILE_REF_SATURATED); - return false; + return __file_ref_put_badval(ref, cnt); } EXPORT_SYMBOL_GPL(__file_ref_put); +/** + * file_ref_put_close - drop a reference expecting it would transition to FILE_REF_NOREF + * @ref: Pointer to the reference count + * + * Semantically it is equivalent to calling file_ref_put(), but it trades lower + * performance in face of other CPUs also modifying the refcount for higher + * performance when this happens to be the last reference. + * + * For the last reference file_ref_put() issues 2 atomics. One to drop the + * reference and another to transition it to FILE_REF_DEAD. This routine does + * the work in one step, but in order to do it has to pre-read the variable which + * decreases scalability. + * + * Use with close() et al, stick to file_ref_put() by default. + */ +bool file_ref_put_close(file_ref_t *ref) +{ + long old, new; + + old = atomic_long_read(&ref->refcnt); + do { + if (unlikely(old < 0)) + return __file_ref_put_badval(ref, old); + + if (old == FILE_REF_ONEREF) + new = FILE_REF_DEAD; + else + new = old - 1; + } while (!atomic_long_try_cmpxchg(&ref->refcnt, &old, new)); + + return new == FILE_REF_DEAD; +} +EXPORT_SYMBOL_GPL(file_ref_put_close); + unsigned int sysctl_nr_open __read_mostly = 1024*1024; unsigned int sysctl_nr_open_min = BITS_PER_LONG; /* our min() is unusable in constant expressions ;-/ */ diff --git a/fs/file_table.c b/fs/file_table.c index 5c00dc38558d..4189c682eb06 100644 --- a/fs/file_table.c +++ b/fs/file_table.c @@ -511,31 +511,37 @@ void flush_delayed_fput(void) } EXPORT_SYMBOL_GPL(flush_delayed_fput); -void fput(struct file *file) +static void __fput_defer_free(struct file *file) { - if (file_ref_put(&file->f_ref)) { - struct task_struct *task = current; + struct task_struct *task = current; - if (unlikely(!(file->f_mode & (FMODE_BACKING | FMODE_OPENED)))) { - file_free(file); + if (unlikely(!(file->f_mode & (FMODE_BACKING | FMODE_OPENED)))) { + file_free(file); + return; + } + if (likely(!in_interrupt() && !(task->flags & PF_KTHREAD))) { + init_task_work(&file->f_task_work, ____fput); + if (!task_work_add(task, &file->f_task_work, TWA_RESUME)) return; - } - if (likely(!in_interrupt() && !(task->flags & PF_KTHREAD))) { - init_task_work(&file->f_task_work, ____fput); - if (!task_work_add(task, &file->f_task_work, TWA_RESUME)) - return; - /* - * After this task has run exit_task_work(), - * task_work_add() will fail. Fall through to delayed - * fput to avoid leaking *file. - */ - } - - if (llist_add(&file->f_llist, &delayed_fput_list)) - schedule_delayed_work(&delayed_fput_work, 1); + /* + * After this task has run exit_task_work(), + * task_work_add() will fail. Fall through to delayed + * fput to avoid leaking *file. + */ } + + if (llist_add(&file->f_llist, &delayed_fput_list)) + schedule_delayed_work(&delayed_fput_work, 1); } +void fput(struct file *file) +{ + if (unlikely(file_ref_put(&file->f_ref))) { + __fput_defer_free(file); + } +} +EXPORT_SYMBOL(fput); + /* * synchronous analog of fput(); for kernel threads that might be needed * in some umount() (and thus can't use flush_delayed_fput() without @@ -549,10 +555,34 @@ void __fput_sync(struct file *file) if (file_ref_put(&file->f_ref)) __fput(file); } - -EXPORT_SYMBOL(fput); EXPORT_SYMBOL(__fput_sync); +/* + * Equivalent to __fput_sync(), but optimized for being called with the last + * reference. + * + * See file_ref_put_close() for details. + */ +void fput_close_sync(struct file *file) +{ + if (unlikely(file_ref_put_close(&file->f_ref))) + __fput(file); +} +EXPORT_SYMBOL(fput_close_sync); + +/* + * Equivalent to fput(), but optimized for being called with the last + * reference. + * + * See file_ref_put_close() for details. + */ +void fput_close(struct file *file) +{ + if (file_ref_put_close(&file->f_ref)) + __fput_defer_free(file); +} +EXPORT_SYMBOL(fput_close); + void __init files_init(void) { struct kmem_cache_args args = { diff --git a/include/linux/file.h b/include/linux/file.h index 302f11355b10..7b04e87cbde6 100644 --- a/include/linux/file.h +++ b/include/linux/file.h @@ -124,6 +124,8 @@ int receive_fd_replace(int new_fd, struct file *file, unsigned int o_flags); extern void flush_delayed_fput(void); extern void __fput_sync(struct file *); +void fput_close_sync(struct file *); +void fput_close(struct file *); extern unsigned int sysctl_nr_open_min, sysctl_nr_open_max; diff --git a/include/linux/file_ref.h b/include/linux/file_ref.h index 9b3a8d9b17ab..f269299941aa 100644 --- a/include/linux/file_ref.h +++ b/include/linux/file_ref.h @@ -62,6 +62,7 @@ static inline void file_ref_init(file_ref_t *ref, unsigned long cnt) } bool __file_ref_put(file_ref_t *ref, unsigned long cnt); +bool file_ref_put_close(file_ref_t *ref); /** * file_ref_get - Acquire one reference on a file From patchwork Tue Mar 4 18:35:04 2025 Content-Type: text/plain; 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(cst-prg-71-44.cust.vodafone.cz. [46.135.71.44]) by smtp.gmail.com with ESMTPSA id 4fb4d7f45d1cf-5e4c3bb747csm8691328a12.42.2025.03.04.10.35.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 04 Mar 2025 10:35:20 -0800 (PST) From: Mateusz Guzik To: brauner@kernel.org, viro@zeniv.linux.org.uk Cc: jack@suse.cz, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Mateusz Guzik Subject: [PATCH v2 2/4] fs: use fput_close_sync() in close() Date: Tue, 4 Mar 2025 19:35:04 +0100 Message-ID: <20250304183506.498724-3-mjguzik@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250304183506.498724-1-mjguzik@gmail.com> References: <20250304183506.498724-1-mjguzik@gmail.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 This bumps open+close rate by 1% on Sapphire Rapids by eliding one atomic. It would be higher if it was not for several other slowdowns of the same nature. Signed-off-by: Mateusz Guzik --- fs/open.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/open.c b/fs/open.c index 57e088c01ea4..fc1c6118eb30 100644 --- a/fs/open.c +++ b/fs/open.c @@ -1615,7 +1615,7 @@ SYSCALL_DEFINE1(close, unsigned int, fd) * We're returning to user space. Don't bother * with any delayed fput() cases. */ - __fput_sync(file); + fput_close_sync(file); if (likely(retval == 0)) return 0; From patchwork Tue Mar 4 18:35:05 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mateusz Guzik X-Patchwork-Id: 14001247 Received: from mail-ed1-f50.google.com (mail-ed1-f50.google.com [209.85.208.50]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CFC7726036C; Tue, 4 Mar 2025 18:35:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.50 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741113326; cv=none; b=NBBUlmqVrJbZaUTW7zzTnydxNr489rZgvFTQq1y//VhTcla1+k6anm9nXTofHeoRs8Z5NwORfcxEsxxctoojHmk8HscLL/efBkltM0xuyKhuTacwuTP/O8bICP1I+VvgqXCZ19TPFGwlEULeBoyVNYHLEUHGypoarm0pMCasTCA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741113326; c=relaxed/simple; bh=Tj/MdgPZ5cCJuJyqipEsMQgzBXtGY6F6q4iEUHpndOo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=FGqI5ysmhr36adBOKxEum4StMAjEC0n1e0nSlM6DEL0DcT2MSTaplsJ03tpo5mL3lWOIgacoWMq38XPmzaYI5iJoEaCdoTnSvtCpARlrX4tmiSWq01oxBdOpOfIeDpzTihcVq23bLtfCVSDT9el7k5iGeRihEezF1glDQwWDkAU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=Qr4gssoa; arc=none smtp.client-ip=209.85.208.50 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Qr4gssoa" Received: by mail-ed1-f50.google.com with SMTP id 4fb4d7f45d1cf-5e04064af07so11116391a12.0; Tue, 04 Mar 2025 10:35:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1741113323; x=1741718123; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=EyDsNpX9HcSDC6V6t1dVpjf3NEtUKhWlmeySG+ENdu8=; b=Qr4gssoazn91fkGY8RdhAuvgWyxQ/Ln19ABxayBzgErbDAvEQT8S6CPEwEGShakG4X HCfO+Z1KWv+5CmG4Dp8ViNLMXcbt6g2I4NFPJfmnhrscjpBc1N+pd0gW89IdnXaT6umv NSfqW8kyw5gX+B5x2w+BRaqUGy1cPWTdL49DFbt4wc3KAhfAVFaK/XxG4V2EBgo1NCb/ vaKsE1dw87GEtA2DvZK10fmgz8BuyCkY+8O1aYSbjAArnx8j1+aZ+o63dj2Ku03A1Anr YiF8w2VwfI4BYMzv1UpHRObwvO5Gh7Wl3EdE+azcA8j4Ak36H4PnIe42rAtOuYscE4Tn niCg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1741113323; x=1741718123; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=EyDsNpX9HcSDC6V6t1dVpjf3NEtUKhWlmeySG+ENdu8=; b=YLTrDP9rVYZDg6Uu3CXT3mNJ19OtKD6qteuoBukYu2F7E50fGE3yNnSDOz3sgotcV3 51SAFnKeUH5y4dJD6RtFVs3tSJ2+S+47cHvC02w6dpJO2lkkq35Ajzalf5bWHnmJMpai 9XhF1ePXxXb/3+rsyTV9RJwiBOS/n3ZzVjB6YfJVDsaSA1iDagiUaSS1rDaZtVoBQBw/ S6k2AAQeAjuqexu2GfjkbYZ6ho0ssVl0u7m1HgaM71NBVfeuPvcrvdA/kk4bUHzXP0qV SX8Z45hIF2TQpovpJ5pn2FuBlsJng+FIt9Uik4TxnUGTJp0mUNO6IXA5VUnngh0FC3Kk 08jg== X-Forwarded-Encrypted: i=1; AJvYcCVNDSBN+MPOBy6Ve8rKeSos7PhCjGziNuRJTgmAWcE03DTXfKgvri7ipUlSjSFGDTRj242oqf9X1+sZAaC/@vger.kernel.org, AJvYcCWN+zxWBrjXH9aj2AE6JU4OP7ELqJc0v/5kM0PLqxmqxv/vVFRby23qZ04bKDthSIgVbkDCZKIBRTMnRH+r@vger.kernel.org X-Gm-Message-State: AOJu0YyYyH63spthe4jIcqIfzE5FXa1EjGscrVjw5Mw2sY0U4ysnUzaG t6P51FGaG+50grULd/CAS/aVJq++5S7k0mu/GWKnflMi3feooY7C X-Gm-Gg: ASbGncscjxLUqtXORW/tDnsrcC/zO4EGEvXKRGyvc3azFa0nCJiIxAXMvPEMKZjQrxo MbbUHX14a08QU47t99PZZ+mtZCsYKFd93ydrFm5h8xp59SmV+QiwcirmoNhN2lPu604+OYr6IGP lcXGUblQhnZdPjbEn7h4fusFau34cgW/dgP9cdpnM2i91u6jNAm0RrMeaU60GB0V/Yb0q2krC+d BYgKtFitQDPfWZJnWhMy5ARX10upSvZIVRzzvWoyeioECkMpBFQ7wM6l8VkQK7C/mT1ux4+fa2H ozkQ8oHB/mb9uxNLEANtFPMc845jpncf4GKCwocLONmOmuGpVaH040NjiXXO X-Google-Smtp-Source: AGHT+IGABG5ux5DyBs31vWizjFg2g8zC/4PRf2kiX5akS7Vj2GWs4WMJ+xD9KZXiN3kx391JN33YOQ== X-Received: by 2002:a05:6402:274e:b0:5d9:a62:32b with SMTP id 4fb4d7f45d1cf-5e59f363d52mr148506a12.7.1741113322607; Tue, 04 Mar 2025 10:35:22 -0800 (PST) Received: from f.. 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[46.135.71.44]) by smtp.gmail.com with ESMTPSA id 4fb4d7f45d1cf-5e4c3bb747csm8691328a12.42.2025.03.04.10.35.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 04 Mar 2025 10:35:21 -0800 (PST) From: Mateusz Guzik To: brauner@kernel.org, viro@zeniv.linux.org.uk Cc: jack@suse.cz, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Mateusz Guzik Subject: [PATCH v2 3/4] fs: use fput_close() in filp_close() Date: Tue, 4 Mar 2025 19:35:05 +0100 Message-ID: <20250304183506.498724-4-mjguzik@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250304183506.498724-1-mjguzik@gmail.com> References: <20250304183506.498724-1-mjguzik@gmail.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 When tracing a kernel build over refcounts seen this is a wash: @[kprobe:filp_close]: [0] 32195 |@@@@@@@@@@ | [1] 164567 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@| I verified vast majority of the skew comes from do_close_on_exec() which could be changed to use a different variant instead. Even without changing that, the 19.5% of calls which got here still can save the extra atomic. Calls here are borderline non-existent compared to fput (over 3.2 mln!), so they should not negatively affect scalability. Signed-off-by: Mateusz Guzik --- fs/open.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/open.c b/fs/open.c index fc1c6118eb30..ffb7e2e5e1ef 100644 --- a/fs/open.c +++ b/fs/open.c @@ -1589,7 +1589,7 @@ int filp_close(struct file *filp, fl_owner_t id) int retval; retval = filp_flush(filp, id); - fput(filp); + fput_close(filp); return retval; } From patchwork Tue Mar 4 18:35:06 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mateusz Guzik X-Patchwork-Id: 14001248 Received: from mail-ed1-f43.google.com (mail-ed1-f43.google.com [209.85.208.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0B5AC2780EC; Tue, 4 Mar 2025 18:35:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.43 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741113327; cv=none; b=jrqQrYfCcUEoPTtHMvhl+W9FRxKyOoLJnDyyXCs9yZsD4JSDesJokwaLZz9i1wANipS4rQkQYZUDCiJHbASCQAJPciSrpPZ6TXep5LVGCAwq1/V3FQAwrd15m830SXQ62DzhJgsa5i2DUqV+Cv9fG9QBIzTH+7RGQBPScj/UGgc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741113327; c=relaxed/simple; bh=P0A0PEjdHHsIeWGrtdLnPuAjyL2aLXxzIEmswgZCJmE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=NTZK3OxomEmiqetP3n1SJrLcugD6ZtcTRgl3NrfpkpGrtfOmFas0aU8Tevpg7aoEfH5q9bGlKyr22iNDCXfQ59FX1DiyJW2VIGobE25vEHWVPyTXTN0Ydk2hFcV9XXU+FvsxP9UZdlMw/DBp5BVYrWg/pmTPSjAVt+4jfk7AL20= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=flO358Uq; arc=none smtp.client-ip=209.85.208.43 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="flO358Uq" Received: by mail-ed1-f43.google.com with SMTP id 4fb4d7f45d1cf-5e0373c7f55so9206727a12.0; Tue, 04 Mar 2025 10:35:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1741113324; x=1741718124; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=t0Cp/31N26M2IM0Uo/PPMwOObDDtMQe4/t93mqj0N+s=; b=flO358UqzcucVXcRjtMH6RCUYEh1lUjUzf9F/0Rn0H5LE1ylJ438QAKhi8LedBmEz8 UL9FipcfU96VwoPcS524Qj/lRZD84t8smykAavcqNjbZ+u7aV/Y15NzO0tHIPgBZqgSA IyPIKm+SGv7N4QxL0THC7wt8i0yBTNetErtKkRgm9H3KyPAaI4xfti+al2FF654alrNt OWSkH1Iw85xTmycS7cKefrm/Ks1QNmfhYLv6zaCbRJ/V9pH9nDMqKM/KuoDiKX+wpUkb yZrg4u6GEF3tvn73/LHQXoTlHTiMc8AKS7gshDR6bR+lOFcdKHlgM4PsExfKTO7h5FZT /iqg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1741113324; x=1741718124; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=t0Cp/31N26M2IM0Uo/PPMwOObDDtMQe4/t93mqj0N+s=; b=v4rJsSm9emspZHdhT7ac9GtragHUfl4chcix1CQgU6qG6uepAqALoLtogMWKutNRir ZkaKRPZUEvCUhiRXqo02jSlBl7i2en/cIALHVCZirTfWPqgE7v7GER8H4NLzo5pn8I9K 84Jx4dFHtsalc0N8YVohEqApXQe7Woeyt9EYVjM62FYi1g3ZqLVmVTzeEV6vJ5EyCkBb 0On/OQ1gVX+xIST9vuDB7N6yS545vuy8eJFAoiPGBFUV2OS/w6BlYBUAiQMk/MvUkwrj F2A8IdUMjS9NdOmh8wpz12MwfM9P8CiQjs5CNmYHiDtZ9Hb538c0pswDWPXlECEuiD22 2b4A== X-Forwarded-Encrypted: i=1; AJvYcCWHF1vRtBHSlTK7sOh5q9fXhk4ynQaJfB41gJfNgwb23vj6N8xdn9rwPquJasEK6iL6B04sN7TweMaqjfQJ@vger.kernel.org, AJvYcCXWg5FG/E12NIi06r9Uiqv/J/Fq5kcQ0kx07/9Fo585h/JmwLxEhBmmsNreoMbW6uqJfcvkHmsRQ6nfLr6l@vger.kernel.org X-Gm-Message-State: AOJu0YzfAKTA3Mm6kwdOrD4ubkOX78AMTUR7gyEleFF/OZ9Z8yeb3hlg WuPfgL5YbFXp59B/B/1x7ten+yY/2mIGYs+0tuq1kFMaEVV5JpKv X-Gm-Gg: ASbGncsmXIMoX4xNMIxJzC+eKu9Lh8Hvhs2Fodp0IrHKlNvqiWzJkMvKa2gUx6B0B2p qyj6mOHcNX69dJ5hdslpUkZMNt9q31+pfmXdB5GedrtOyFI6DuOe88Y0y3a+vGnChObD+v941/z pgaAGnCGoSIk9sVqA1zRlZYJE/HjLrO+do3ojbhzaha5CSGlk8YBTHCgteOodQYmErjtqldjuGk HVrhxOe2uWkWYt632TYQ5e4X3GYswjW10rmeyBZrGscG8x8hHlQys+aGGpZYqlcA2I7RWTYE9PY OirITul/UrtIMfh+fETnwXOjYGKs1H7uyAQ46Yo0b83kxk3Lx9lyt0DuSWK0 X-Google-Smtp-Source: AGHT+IEFtGkcRCG36c6CxhgM4PPufjS2PQKe2hotX1hKro6brhz9YbPJ17OkASe0bM1AkzzAUuqLDw== X-Received: by 2002:a05:6402:5c8:b0:5d4:1ac2:277f with SMTP id 4fb4d7f45d1cf-5e59f389103mr129462a12.9.1741113324136; Tue, 04 Mar 2025 10:35:24 -0800 (PST) Received: from f.. (cst-prg-71-44.cust.vodafone.cz. [46.135.71.44]) by smtp.gmail.com with ESMTPSA id 4fb4d7f45d1cf-5e4c3bb747csm8691328a12.42.2025.03.04.10.35.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 04 Mar 2025 10:35:23 -0800 (PST) From: Mateusz Guzik To: brauner@kernel.org, viro@zeniv.linux.org.uk Cc: jack@suse.cz, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Mateusz Guzik Subject: [PATCH v2 4/4] fs: use fput_close() in path_openat() Date: Tue, 4 Mar 2025 19:35:06 +0100 Message-ID: <20250304183506.498724-5-mjguzik@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250304183506.498724-1-mjguzik@gmail.com> References: <20250304183506.498724-1-mjguzik@gmail.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 This bumps failing open rate by 1.7% on Sapphire Rapids by avoiding one atomic. Signed-off-by: Mateusz Guzik --- fs/namei.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/namei.c b/fs/namei.c index 8ce8e6038346..d38b8dc16b4b 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -4014,7 +4014,7 @@ static struct file *path_openat(struct nameidata *nd, WARN_ON(1); error = -EINVAL; } - fput(file); + fput_close(file); if (error == -EOPENSTALE) { if (flags & LOOKUP_RCU) error = -ECHILD;