[PATCH v3 5/5] pid: use pid_has_task() in pidfd_open()
From: Christian Brauner <hidden>
Date: 2019-10-17 10:19:17
Also in:
linux-kselftest, lkml
Subsystem:
the rest · Maintainer:
Linus Torvalds
Use the new pid_has_task() helper in pidfd_open(). This simplifies the
code and avoids taking rcu_read_{lock,unlock}() and leads to overall
nicer code.
Signed-off-by: Christian Brauner <redacted>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
---
/* pidfd selftests */
passed
/* v1 */
patch not present
/* v2 */
Link: https://lore.kernel.org/r/20191016153606.2326-5-christian.brauner@ubuntu.com (local)
patch introduced
/* v3 */
- Oleg Nesterov [off-list ref]:
- s/task_alive/pid_has_task/
---
kernel/pid.c | 12 +++++-------
1 file changed, 5 insertions(+), 7 deletions(-)
diff --git a/kernel/pid.c b/kernel/pid.c
index 124d40b239b1..7b5f6c963d72 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c@@ -497,7 +497,7 @@ static int pidfd_create(struct pid *pid) */ SYSCALL_DEFINE2(pidfd_open, pid_t, pid, unsigned int, flags) { - int fd, ret; + int fd; struct pid *p; if (flags)
@@ -510,13 +510,11 @@ SYSCALL_DEFINE2(pidfd_open, pid_t, pid, unsigned int, flags) if (!p) return -ESRCH; - ret = 0; - rcu_read_lock(); - if (!pid_task(p, PIDTYPE_TGID)) - ret = -EINVAL; - rcu_read_unlock(); + if (pid_has_task(p, PIDTYPE_TGID)) + fd = pidfd_create(p); + else + fd = -EINVAL; - fd = ret ?: pidfd_create(p); put_pid(p); return fd; }
--
2.23.0