From 8fb0b0ce288d38d78685a9d6f6320339afadf709 Mon Sep 17 00:00:00 2001 From: Riley Andrews Date: Thu, 29 Jun 2017 12:01:37 -0700 Subject: [PATCH] binder: Use wake up hint for synchronous transactions. commit 00b40d613352c623aaae88a44e5ded7c912909d7 upstream. Use wake_up_interruptible_sync() to hint to the scheduler binder transactions are synchronous wakeups. Disable preemption while waking to avoid ping-ponging on the binder lock. Signed-off-by: Todd Kjos Signed-off-by: Omprakash Dhyade Signed-off-by: Greg Kroah-Hartman --- drivers/android/binder.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/android/binder.c b/drivers/android/binder.c index abd10af..5ce7ee9 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -1724,8 +1724,12 @@ static void binder_transaction(struct binder_proc *proc, list_add_tail(&t->work.entry, target_list); tcomplete->type = BINDER_WORK_TRANSACTION_COMPLETE; list_add_tail(&tcomplete->entry, &thread->todo); - if (target_wait) - wake_up_interruptible(target_wait); + if (target_wait) { + if (reply || !(t->flags & TF_ONE_WAY)) + wake_up_interruptible_sync(target_wait); + else + wake_up_interruptible(target_wait); + } return; err_get_unused_fd_failed: -- 2.7.4