From: Mateusz Guzik <mjguzik@gmail.com>
Date: Thu, 6 Feb 2025 16:44:11 +0000 (+0100)
Subject: exit: hoist get_pid() in release_task() outside of tasklist_lock
X-Git-Tag: v6.15-rc1~236^2^2~3
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6731cd97e60d6f3a30057c0fc513aed543187104;p=thirdparty%2Flinux.git

exit: hoist get_pid() in release_task() outside of tasklist_lock

Reduces hold time as get_pid() contains an atomic.

Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://lore.kernel.org/r/20250206164415.450051-3-mjguzik@gmail.com
Acked-by: "Liam R. Howlett" <Liam.Howlett@Oracle.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
---

diff --git a/kernel/exit.c b/kernel/exit.c
index a00273db024b3..ebc1c5bec5122 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -240,9 +240,10 @@ repeat:
 
 	cgroup_release(p);
 
+	thread_pid = get_pid(p->thread_pid);
+
 	write_lock_irq(&tasklist_lock);
 	ptrace_release_task(p);
-	thread_pid = get_pid(p->thread_pid);
 	__exit_signal(p);
 
 	/*