From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta1.migadu.com (out-200.mta1.migadu.com [95.215.58.200]) (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 77E85355F4E for ; Thu, 13 Aug 2026 03:26:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.200 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786591606; cv=none; b=NzG2x1CbwFWmtJ6qyi+1KOKGqocdJnJ8gnuwdItyNS1vEHBjAU5z5hqqkAhTh/nCm8LXChMkIR0+RMyWDWHXD7glAxOD+hLkMaXqO4hH9LFPGU8ctReBj8iX6YB70tp+p7v83+DSyWBPrzaxqv/PLuiOLUcZwEK8ofEk+P74pPY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786591606; c=relaxed/simple; bh=zXqX3xtuvlWxgzbVzwt5N7dofujH4OIOZtshciguoJg=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=CVGwHlZKvo2xdqELVkzqtMM6RiScCdQV7BTDwpxkM0odzv6Ad1u6QkJY2Iaj5geIb/BpKuZnW31aiYGI2SkOO955PBdWbapysq61LTYOGAIRAbeRfBV09jHHtUAikXdZcGkDr00zuvU8gtmeu0xv3iJu6/2it6p/CVFgPtIdIMs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=X1cnMHYr; arc=none smtp.client-ip=95.215.58.200 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="X1cnMHYr" X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=zXqX3xtuvlWxgzbVzwt5N7dofujH4OIOZtshciguoJg=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1786591600; v=1; x=1787196400; b=X1cnMHYrl9+2SjI9i+QXogKRA66Mp4SADc430fKkaqSvJOD3s1rEI5rpfjcPtM9ZLtor8Xbi E3819XHHTVyCX+3lidDvIK3wTSeBd+boRNxt2MbhFxEsBf0PR22IyVkecxX9FThKli501Mzm8go 1Y06OHj+YPRGfxsLT8enAGFw= X-Envelope-To: linux-kernel@vger.kernel.org Received: from localhost.localdomain (223.70.159.239) by smtp.migadu.com with ESMTPS id a81e386923b95674; Thu, 13 Aug 2026 03:26:40 +0000 X-Migadu-Flow: FLOW_OUT From: Ye Liu To: Michal Hocko , Andrew Morton Cc: Ye Liu , David Rientjes , Shakeel Butt , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH] mm/oom_kill: simplify remaining RCU sections with guard(rcu) Date: Thu, 13 Aug 2026 11:26:33 +0800 Message-Id: <20260813032634.344946-1-ye.liu@linux.dev> X-Mailer: git-send-email 2.25.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Ye Liu Replace the remaining manual rcu_read_lock()/rcu_read_unlock() pairs in oom_cpuset_eligible(), select_bad_process(), dump_tasks(), task_will_free_mem(), and __oom_kill_process() with guard(rcu)() for consistency and simpler control flow. Signed-off-by: Ye Liu --- mm/oom_kill.c | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-) diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 4b5c70aaece4..8bbb5ca00bb6 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -94,7 +94,7 @@ static bool oom_cpuset_eligible(struct task_struct *start, bool ret = false; const nodemask_t *mask = oc->nodemask; - rcu_read_lock(); + guard(rcu)(); for_each_thread(start, tsk) { if (mask) { /* @@ -114,7 +114,6 @@ static bool oom_cpuset_eligible(struct task_struct *start, if (ret) break; } - rcu_read_unlock(); return ret; } @@ -368,11 +367,10 @@ static void select_bad_process(struct oom_control *oc) else { struct task_struct *p; - rcu_read_lock(); + guard(rcu)(); for_each_process(p) if (oom_evaluate_task(p, oc)) break; - rcu_read_unlock(); } } @@ -430,14 +428,13 @@ static void dump_tasks(struct oom_control *oc) struct task_struct *p; int i = 0; - rcu_read_lock(); + guard(rcu)(); for_each_process(p) { /* Avoid potential softlockup warning */ if ((++i & 1023) == 0) touch_softlockup_watchdog(); dump_task(p, oc); } - rcu_read_unlock(); } } @@ -894,7 +891,7 @@ static bool task_will_free_mem(struct task_struct *task) * are dying as well to make sure that a) nobody pins its mm and * b) the task is also reapable by the oom reaper. */ - rcu_read_lock(); + guard(rcu)(); for_each_process(p) { if (!process_shares_mm(p, mm)) continue; @@ -904,7 +901,6 @@ static bool task_will_free_mem(struct task_struct *task) if (!ret) break; } - rcu_read_unlock(); return ret; } @@ -960,7 +956,7 @@ static void __oom_kill_process(struct task_struct *victim, const char *message) * That thread will now get access to memory reserves since it has a * pending fatal signal. */ - rcu_read_lock(); + guard(rcu)(); for_each_process(p) { if (!process_shares_mm(p, mm)) continue; @@ -982,7 +978,6 @@ static void __oom_kill_process(struct task_struct *victim, const char *message) continue; do_send_sig_info(SIGKILL, SEND_SIG_PRIV, p, PIDTYPE_TGID); } - rcu_read_unlock(); if (can_oom_reap) queue_oom_reaper(victim); -- 2.25.1