jcs.org
qemu with hax to log dma reads & writes
jcs.org/2018/11/12/vfio
coroutine: Add qemu_co_mutex_assert_locked()
Some functions require that the caller holds a certain CoMutex for them
to operate correctly. Add a function so that they can assert the lock is
really held.
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Tested-by: Michael Weiser <michael.weiser@gmx.de>
Reviewed-by: Michael Weiser <michael.weiser@gmx.de>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Max Reitz <mreitz@redhat.com>
+15
+15
include/qemu/coroutine.h
+15
include/qemu/coroutine.h
···
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*/
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void coroutine_fn qemu_co_mutex_unlock(CoMutex *mutex);
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/**
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* Assert that the current coroutine holds @mutex.
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*/
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static inline coroutine_fn void qemu_co_mutex_assert_locked(CoMutex *mutex)
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{
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/*
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* mutex->holder doesn't need any synchronisation if the assertion holds
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* true because the mutex protects it. If it doesn't hold true, we still
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* don't mind if another thread takes or releases mutex behind our back,
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* because the condition will be false no matter whether we read NULL or
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* the pointer for any other coroutine.
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*/
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assert(atomic_read(&mutex->locked) &&
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mutex->holder == qemu_coroutine_self());
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}
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/**
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* CoQueues are a mechanism to queue coroutines in order to continue executing