Messages in this thread Patch in this message | | | From | Thomas Gleixner <> | Subject | [patch V5 60/72] futex: Remove bogus condition for requeue PI | Date | Sun, 15 Aug 2021 23:29:09 +0200 (CEST) |
| |
For requeue PI it's required to establish PI state for the PI futex to which waiters are requeued. This either acquires the user space futex on behalf of the top most waiter on the inner 'waitqueue' futex or attaches to the PI state of an existing waiter or creates on attached to the owner of the futex.
This code can retry in case of failure, but retry can never happen when the pi state was successfully created. The condition to run this code is:
(task_count - nr_wake) < nr_requeue
which is always true because:
task_count = 0 nr_wake = 1 nr_requeue >= 0
Remove it all together.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> --- V4: New patch --- kernel/futex.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/kernel/futex.c +++ b/kernel/futex.c @@ -2000,7 +2000,7 @@ static int futex_requeue(u32 __user *uad } } - if (requeue_pi && (task_count - nr_wake < nr_requeue)) { + if (requeue_pi) { struct task_struct *exiting = NULL; /*
| |