linux-kernel - [PATCH] once: Don't use a work queue to reset sleepable static key

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Message-ID: <20260108232717.14411-1-tony.luck@intel.com>
Date: Thu,  8 Jan 2026 15:27:17 -0800
From: Tony Luck <tony.luck@...el.com>
To: Andrew Morton <akpm@...ux-foundation.org>
Cc: Eric Dumazet <edumazet@...gle.com>,
	Reinette Chatre <reinette.chatre@...el.com>,
	linux-kernel@...r.kernel.org,
	patches@...ts.linux.dev,
	Tony Luck <tony.luck@...el.com>
Subject: [PATCH] once: Don't use a work queue to reset sleepable static key

Pointless overhead to use a work queue to reset the static key
for a DO_ONCE_SLEEPABLE() invocation.

Reported-by: Reinette Chatre <reinette.chatre@...el.com>
Signed-off-by: Tony Luck <tony.luck@...el.com>
---
 lib/once.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/once.c b/lib/once.c
index 2c306f0e891e..d83bdde78ced 100644
--- a/lib/once.c
+++ b/lib/once.c
@@ -93,6 +93,7 @@ void __do_once_sleepable_done(bool *done, struct static_key_true *once_key,
 {
 	*done = true;
 	mutex_unlock(&once_mutex);
-	once_disable_jump(once_key, mod);
+	BUG_ON(!static_key_enabled(once_key));
+	static_branch_disable(once_key);
 }
 EXPORT_SYMBOL(__do_once_sleepable_done);
-- 
2.52.0