forked from Minki/linux
8d53fa1904
While going over the code I noticed that xchg_tail() is a RELEASE but had no obvious pairing commented. It pairs with a somewhat unique address dependency through decode_tail(). So the store-release of xchg_tail() is paired by the address dependency of the load of xchg_tail followed by the dereference from the pointer computed from that load. The @old -> @prev transformation itself is pure, and therefore does not depend on external state, so that is immaterial wrt. ordering. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Waiman Long <waiman.long@hpe.com> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> |
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| .. | ||
| lglock.c | ||
| 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 | ||