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[46.135.95.94]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-ab6e47d06e5sm1167625566b.63.2025.02.05.11.32.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 05 Feb 2025 11:32:58 -0800 (PST) From: Mateusz Guzik To: ebiederm@xmission.com, oleg@redhat.com Cc: brauner@kernel.org, akpm@linux-foundation.org, Liam.Howlett@oracle.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Mateusz Guzik Subject: [PATCH v4 2/5] exit: hoist get_pid() in release_task() outside of tasklist_lock Date: Wed, 5 Feb 2025 20:32:18 +0100 Message-ID: <20250205193221.402150-3-mjguzik@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250205193221.402150-1-mjguzik@gmail.com> References: <20250205193221.402150-1-mjguzik@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" reduces hold time as get_pid() contains an atomic Reviewed-by: Oleg Nesterov Signed-off-by: Mateusz Guzik --- kernel/exit.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/exit.c b/kernel/exit.c index c79b41509cd3..b5c0cbc6bdfb 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -248,9 +248,10 @@ void release_task(struct task_struct *p) =20 cgroup_release(p); =20 + thread_pid =3D get_pid(p->thread_pid); + write_lock_irq(&tasklist_lock); ptrace_release_task(p); - thread_pid =3D get_pid(p->thread_pid); __exit_signal(p); =20 /* --=20 2.43.0