[tip: sched/core] sched: Reenable interrupts in do_sched_yield()

[tip-bot2 for Thomas Gleixner]

The following commit has been merged into the sched/core branch of tip:

Commit-ID:     345a957fcc95630bf5535d7668a59ed983eb49a7
Gitweb:        https://git.kernel.org/tip/345a957fcc95630bf5535d7668a59ed983eb49a7
Author:        Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate:    Tue, 20 Oct 2020 16:46:55 +02:00
Committer:     Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Thu, 29 Oct 2020 11:00:31 +01:00

sched: Reenable interrupts in do_sched_yield()

do_sched_yield() invokes schedule() with interrupts disabled which is
not allowed. This goes back to the pre git era to commit a6efb709806c
("[PATCH] irqlock patch 2.5.27-H6") in the history tree.

Reenable interrupts and remove the misleading comment which "explains" it.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/87r1pt7y5c.fsf@xxxxxxxxxxxxxxxxxxxxxxx
---
 kernel/sched/core.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index d2003a7..6f533bb 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -6094,12 +6094,8 @@ static void do_sched_yield(void)
 	schedstat_inc(rq->yld_count);
 	current->sched_class->yield_task(rq);
 
-	/*
-	 * Since we are going to call schedule() anyway, there's
-	 * no need to preempt or enable interrupts:
-	 */
 	preempt_disable();
-	rq_unlock(rq, &rf);
+	rq_unlock_irq(rq, &rf);
 	sched_preempt_enable_no_resched();
 
 	schedule();