From: Thomas Gleixner <tglx@linutronix.de>
Date: Sat, 18 Dec 2021 09:57:03 +0000 (+0100)
Subject: Merge branch 'locking/urgent' into locking/core
X-Git-Tag: v5.17-rc1~120^2
X-Git-Url: https://repo.jachan.dev/linux.git/commitdiff_plain/f16cc980d649e664b8f41e1bbaba50255d24e5d1?hp=-c

Merge branch 'locking/urgent' into locking/core

Pick up the spin loop condition fix.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---

f16cc980d649e664b8f41e1bbaba50255d24e5d1
diff --combined kernel/locking/rtmutex.c
index 0c1f2e3f019a,1f25a4d7de27..8555c4efe97c
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@@ -1103,11 -1103,8 +1103,11 @@@ static int __sched task_blocks_on_rt_mu
  	 * the other will detect the deadlock and return -EDEADLOCK,
  	 * which is wrong, as the other waiter is not in a deadlock
  	 * situation.
 +	 *
 +	 * Except for ww_mutex, in that case the chain walk must already deal
 +	 * with spurious cycles, see the comments at [3] and [6].
  	 */
 -	if (owner == task)
 +	if (owner == task && !(build_ww_mutex() && ww_ctx))
  		return -EDEADLK;
  
  	raw_spin_lock(&task->pi_lock);
@@@ -1382,8 -1379,9 +1382,8 @@@ static bool rtmutex_spin_on_owner(struc
  		 *    for CONFIG_PREEMPT_RCU=y)
  		 *  - the VCPU on which owner runs is preempted
  		 */
 -		if (!owner->on_cpu || need_resched() ||
 -		    !rt_mutex_waiter_is_top_waiter(lock, waiter) ||
 -		    vcpu_is_preempted(task_cpu(owner))) {
 +		if (!owner_on_cpu(owner) || need_resched() ||
- 		    rt_mutex_waiter_is_top_waiter(lock, waiter)) {
++		    !rt_mutex_waiter_is_top_waiter(lock, waiter)) {
  			res = false;
  			break;
  		}