forked from Minki/linux
0aa1125fa8
Rename __down_read() in __down_read_common() and teach it to abort waiting in case of pending signals and killable state argument passed. Note, that we shouldn't wake anybody up in EINTR path, as: We check for signal_pending_state() after (!waiter.task) test and under spinlock. So, current task wasn't able to be woken up. It may be in two cases: a writer is owner of the sem, or a writer is a first waiter of the sem. If a writer is owner of the sem, no one else may work with it in parallel. It will wake somebody, when it call up_write() or downgrade_write(). If a writer is the first waiter, it will be woken up, when the last active reader releases the sem, and sem->count became 0. Also note, that set_current_state() may be moved down to schedule() (after !waiter.task check), as all assignments in this type of semaphore (including wake_up), occur under spinlock, so we can't miss anything. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: arnd@arndb.de Cc: avagin@virtuozzo.com Cc: davem@davemloft.net Cc: fenghua.yu@intel.com Cc: gorcunov@virtuozzo.com Cc: heiko.carstens@de.ibm.com Cc: hpa@zytor.com Cc: ink@jurassic.park.msu.ru Cc: mattst88@gmail.com Cc: rth@twiddle.net Cc: schwidefsky@de.ibm.com Cc: tony.luck@intel.com Link: http://lkml.kernel.org/r/149789533283.9059.9829416940494747182.stgit@localhost.localdomain Signed-off-by: Ingo Molnar <mingo@kernel.org> |
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| .. | ||
| lockdep_internals.h | ||
| lockdep_proc.c | ||
| lockdep_states.h | ||
| lockdep.c | ||
| locktorture.c | ||
| Makefile | ||
| mcs_spinlock.h | ||
| mutex-debug.c | ||
| mutex-debug.h | ||
| mutex.c | ||
| mutex.h | ||
| osq_lock.c | ||
| percpu-rwsem.c | ||
| qrwlock.c | ||
| qspinlock_paravirt.h | ||
| qspinlock_stat.h | ||
| qspinlock.c | ||
| rtmutex_common.h | ||
| rtmutex-debug.c | ||
| rtmutex-debug.h | ||
| rtmutex.c | ||
| rtmutex.h | ||
| rwsem-spinlock.c | ||
| rwsem-xadd.c | ||
| rwsem.c | ||
| rwsem.h | ||
| semaphore.c | ||
| spinlock_debug.c | ||
| spinlock.c | ||
| test-ww_mutex.c | ||