The following commit has been merged into the irq/core branch of tip: Commit-ID: d2da74d1278a1b51ef18beafa9da770f0db1c617 Gitweb: https://git.kernel.org/tip/d2da74d1278a1b51ef18beafa9da770f0db1c617 Author: Thomas Gleixner <[email protected]> AuthorDate: Tue, 09 Mar 2021 09:42:04 +01:00 Committer: Thomas Gleixner <[email protected]> CommitterDate: Wed, 17 Mar 2021 16:33:51 +01:00
tasklets: Replace barrier() with cpu_relax() in tasklet_unlock_wait() A barrier() in a tight loop which waits for something to happen on a remote CPU is a pointless exercise. Replace it with cpu_relax() which allows HT siblings to make progress. Signed-off-by: Thomas Gleixner <[email protected]> Tested-by: Sebastian Andrzej Siewior <[email protected]> Acked-by: Peter Zijlstra (Intel) <[email protected]> Link: https://lore.kernel.org/r/[email protected] --- include/linux/interrupt.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h index 2b98156..d689fd7 100644 --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -672,7 +672,8 @@ static inline void tasklet_unlock(struct tasklet_struct *t) static inline void tasklet_unlock_wait(struct tasklet_struct *t) { - while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); } + while (test_bit(TASKLET_STATE_RUN, &t->state)) + cpu_relax(); } #else #define tasklet_trylock(t) 1
