Peter Zijlstra 35bdb300ca locking/mutex: Remove wakeups from under mutex::wait_lock ...

[ Upstream commit 894d1b3db4 ]

In preparation to nest mutex::wait_lock under rq::lock we need
to remove wakeups from under it.

Do this by utilizing wake_qs to defer the wakeup until after the
lock is dropped.

[Heavily changed after 55f036ca7e ("locking: WW mutex cleanup") and
08295b3b5b ("locking: Implement an algorithm choice for Wound-Wait
mutexes")]
[jstultz: rebased to mainline, added extra wake_up_q & init
 to avoid hangs, similar to Connor's rework of this patch]

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: John Stultz <jstultz@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Metin Kaya <metin.kaya@arm.com>
Acked-by: Davidlohr Bueso <dave@stgolabs.net>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Tested-by: Metin Kaya <metin.kaya@arm.com>
Link: https://lore.kernel.org/r/20241009235352.1614323-2-jstultz@google.com
Stable-dep-of: 40a25d59e8 ("locking/rtmutex: Skip remove_waiter() when waiter is not enqueued")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2026-07-04 13:43:26 +02:00

..

irqflag-debug.c

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lock_events_list.h

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lock_events.c

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lock_events.h

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lockdep_internals.h

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lockdep_proc.c

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lockdep_states.h

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lockdep.c

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locktorture.c

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Makefile

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mcs_spinlock.h

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mutex-debug.c

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mutex.c

locking/mutex: Remove wakeups from under mutex::wait_lock

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mutex.h

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osq_lock.c

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percpu-rwsem.c

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qrwlock.c

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qspinlock_paravirt.h

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qspinlock_stat.h

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qspinlock.c

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rtmutex_api.c

locking/mutex: Remove wakeups from under mutex::wait_lock

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rtmutex_common.h

locking/mutex: Remove wakeups from under mutex::wait_lock

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rtmutex.c

locking/mutex: Remove wakeups from under mutex::wait_lock

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rwbase_rt.c

locking/mutex: Remove wakeups from under mutex::wait_lock

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rwsem.c

locking/mutex: Remove wakeups from under mutex::wait_lock

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semaphore.c

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spinlock_debug.c

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spinlock_rt.c

locking/mutex: Remove wakeups from under mutex::wait_lock

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spinlock.c

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test-ww_mutex.c

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ww_mutex.h

locking/mutex: Remove wakeups from under mutex::wait_lock

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ww_rt_mutex.c

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