From: Jason Low <jason.low2@hpe.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: jason.low2@hpe.com, Ingo Molnar <mingo@redhat.com>,
imre.deak@intel.com, linux-kernel@vger.kernel.org,
Waiman Long <Waiman.Long@hpe.com>,
Davidlohr Bueso <dave@stgolabs.net>,
Tim Chen <tim.c.chen@linux.intel.com>,
terry.rudd@hpe.com, "Paul E. McKenney" <paulmck@us.ibm.com>
Subject: Re: [PATCH v2] locking/mutex: Prevent lock starvation when spinning is enabled
Date: Wed, 10 Aug 2016 19:30:26 -0700 [thread overview]
Message-ID: <1470882626.17361.18.camel@j-VirtualBox> (raw)
In-Reply-To: <1470854648.17361.9.camel@j-VirtualBox>
On Wed, 2016-08-10 at 11:44 -0700, Jason Low wrote:
> @@ -917,11 +976,12 @@ EXPORT_SYMBOL(mutex_trylock);
> int __sched
> __ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
> {
> - int ret;
> + int ret = 1;
>
> might_sleep();
>
> - ret = __mutex_fastpath_lock_retval(&lock->base.count);
> + if (!need_yield_to_waiter(lock))
> + ret = __mutex_fastpath_lock_retval(&lock->base.count);
>
> if (likely(!ret)) {
> ww_mutex_set_context_fastpath(lock, ctx);
> @@ -935,11 +995,12 @@ EXPORT_SYMBOL(__ww_mutex_lock);
> int __sched
> __ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
> {
> - int ret;
> + int ret = 1;
>
> might_sleep();
>
> - ret = __mutex_fastpath_lock_retval(&lock->base.count);
> + if (!need_yield_to_waiter(lock))
And we would need to pass &lock->base instead of lock since lock is
struct ww_mutex * here.
next prev parent reply other threads:[~2016-08-11 2:39 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-08-10 18:44 [PATCH v2] locking/mutex: Prevent lock starvation when spinning is enabled Jason Low
2016-08-10 20:00 ` kbuild test robot
2016-08-10 20:01 ` kbuild test robot
2016-08-16 20:19 ` Jason Low
2016-08-10 22:07 ` Jason Low
2016-08-11 2:30 ` Jason Low [this message]
2016-08-11 15:40 ` Waiman Long
2016-08-16 19:44 ` Jason Low
2016-08-17 1:41 ` Wanpeng Li
2016-08-17 18:30 ` Jason Low
2016-08-18 0:38 ` Wanpeng Li
2016-08-18 14:14 ` Peter Zijlstra
2016-08-18 15:22 ` Waiman Long
2016-08-18 14:27 ` Peter Zijlstra
2016-08-18 15:18 ` Peter Zijlstra
2016-08-18 15:30 ` Peter Zijlstra
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