From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 034A663CF for ; Fri, 25 Apr 2025 00:28:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745540908; cv=none; b=ImCzObPYdj68vJ6bQrOhGCFZHrSqKIOly8S+rn8kL4eAIPf7C2/nj175kDQ6cKFytyXKM3PYFKAHMBENqAkDmD2nlvomtIhS68RLH8u2VnPqC2MvA4p0NIUwGww8TFC5bm4W9h1OxazGZa71lpw5ROK3U0zbeIfcCzh+ew7SFoA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745540908; c=relaxed/simple; bh=4wqrZS8w8y2/rj1FFojJ0UAmC8rCc5qzsJcrtlx4m+c=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=jSZ972FgYEai42vkgjVh9RbkviCpUb4+otR9PrQ2y5qqflCKXJMSX28xDAwCMHSqXzjhs1tI69iXPJBH0eY/3LMwwHIyXZyqedXgESOdS/mh21wm1x2iWyl/zzG4dy0SV9Dx9UWPl6t9/18ynSpF+PJRd6G9SSb2/7IgnOS43ts= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Dq9Ij3tC; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Dq9Ij3tC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C5AB7C4CEF3; Fri, 25 Apr 2025 00:28:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1745540907; bh=4wqrZS8w8y2/rj1FFojJ0UAmC8rCc5qzsJcrtlx4m+c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Dq9Ij3tCC+LdKkmjVzyS6GOA3/i+t1JBs/ajvrmahgbynTFpPFLXUjo369R54Z1yf 0CLziiLcGq7xl5vG6KE3XCZoi1b+YDAlBYD6M2APjp/1iFU1LW6UQtsv0B6ERPcm2N FJlcLcB6TWjiilMDeEy99x+3dLVu2lkXDBih5Bbi2+ahgg06mt3Q/VsPqdxPlRLNqV QZm/FeSVvp34lwTZNBqahzbaYj9JG0BBTMk2/d5lZaPIdI6tUow93YYIh2wbfqjjLv UCgORPSipuwBaN5yzVoBUPvHODyOiW4dO8tj73Si+RJPsG9Ssc9t130pkE139QUfFE uBXsaKhyxntMQ== Received: by paulmck-ThinkPad-P17-Gen-1.home (Postfix, from userid 1000) id 319E5CE19CE; Thu, 24 Apr 2025 17:28:27 -0700 (PDT) From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: kernel-team@meta.com, Andrew Morton , Kuniyuki Iwashima , Mateusz Guzik , Petr Mladek , Steven Rostedt , John Ogness , Sergey Senozhatsky , Jon Pan-Doh , Bjorn Helgaas , Karolina Stolarek , "Paul E. McKenney" Subject: [PATCH v3 06/20] ratelimit: Convert the ->missed field to atomic_t Date: Thu, 24 Apr 2025 17:28:12 -0700 Message-Id: <20250425002826.3431914-6-paulmck@kernel.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <72ee57b8-9e2a-4cad-aaa0-1e3353d146d8@paulmck-laptop> References: <72ee57b8-9e2a-4cad-aaa0-1e3353d146d8@paulmck-laptop> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The ratelimit_state structure's ->missed field is sometimes incremented locklessly, and it would be good to avoid lost counts. This is also needed to count the number of misses due to try-lock failure. Therefore, convert the rratelimit_state structure's ->missed field to atomic_t. Link: https://lore.kernel.org/all/fbe93a52-365e-47fe-93a4-44a44547d601@paulmck-laptop/ Link: https://lore.kernel.org/all/20250423115409.3425-1-spasswolf@web.de/ Signed-off-by: Paul E. McKenney Reviewed-by: Petr Mladek Cc: Andrew Morton Cc: Kuniyuki Iwashima Cc: Mateusz Guzik Cc: Steven Rostedt Cc: John Ogness Cc: Sergey Senozhatsky --- include/linux/ratelimit.h | 9 +++------ include/linux/ratelimit_types.h | 2 +- lib/ratelimit.c | 2 +- 3 files changed, 5 insertions(+), 8 deletions(-) diff --git a/include/linux/ratelimit.h b/include/linux/ratelimit.h index 8400c5356c187..c78b92b3e5cd8 100644 --- a/include/linux/ratelimit.h +++ b/include/linux/ratelimit.h @@ -24,20 +24,17 @@ static inline void ratelimit_default_init(struct ratelimit_state *rs) static inline void ratelimit_state_inc_miss(struct ratelimit_state *rs) { - rs->missed++; + atomic_inc(&rs->missed); } static inline int ratelimit_state_get_miss(struct ratelimit_state *rs) { - return rs->missed; + return atomic_read(&rs->missed); } static inline int ratelimit_state_reset_miss(struct ratelimit_state *rs) { - int ret = rs->missed; - - rs->missed = 0; - return ret; + return atomic_xchg_relaxed(&rs->missed, 0); } static inline void ratelimit_state_reset_interval(struct ratelimit_state *rs, int interval_init) diff --git a/include/linux/ratelimit_types.h b/include/linux/ratelimit_types.h index 765232ce0b5e9..d21fe82b67f67 100644 --- a/include/linux/ratelimit_types.h +++ b/include/linux/ratelimit_types.h @@ -18,7 +18,7 @@ struct ratelimit_state { int interval; int burst; int printed; - int missed; + atomic_t missed; unsigned int flags; unsigned long begin; }; diff --git a/lib/ratelimit.c b/lib/ratelimit.c index 85e22f00180c5..18703f92d73e7 100644 --- a/lib/ratelimit.c +++ b/lib/ratelimit.c @@ -66,7 +66,7 @@ int ___ratelimit(struct ratelimit_state *rs, const char *func) rs->printed++; ret = 1; } else { - rs->missed++; + ratelimit_state_inc_miss(rs); ret = 0; } raw_spin_unlock_irqrestore(&rs->lock, flags); -- 2.40.1