Commit-ID: f9c811fac48cfbbfb452b08d1042386947868d07 Gitweb: https://git.kernel.org/tip/f9c811fac48cfbbfb452b08d1042386947868d07 Author: Will Deacon <will.dea...@arm.com> AuthorDate: Thu, 26 Apr 2018 11:34:21 +0100 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Fri, 27 Apr 2018 09:48:49 +0200
locking/qspinlock: Use atomic_cond_read_acquire() Rather than dig into the counter field of the atomic_t inside the qspinlock structure so that we can call smp_cond_load_acquire(), use atomic_cond_read_acquire() instead, which operates on the atomic_t directly. Signed-off-by: Will Deacon <will.dea...@arm.com> Acked-by: Peter Zijlstra (Intel) <pet...@infradead.org> Acked-by: Waiman Long <long...@redhat.com> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Thomas Gleixner <t...@linutronix.de> Cc: boqun.f...@gmail.com Cc: linux-arm-ker...@lists.infradead.org Cc: paul...@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/1524738868-31318-8-git-send-email-will.dea...@arm.com Signed-off-by: Ingo Molnar <mi...@kernel.org> --- kernel/locking/qspinlock.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/kernel/locking/qspinlock.c b/kernel/locking/qspinlock.c index b51494a50b1e..56af1fa9874d 100644 --- a/kernel/locking/qspinlock.c +++ b/kernel/locking/qspinlock.c @@ -337,8 +337,8 @@ void queued_spin_lock_slowpath(struct qspinlock *lock, u32 val) * barriers. */ if (val & _Q_LOCKED_MASK) { - smp_cond_load_acquire(&lock->val.counter, - !(VAL & _Q_LOCKED_MASK)); + atomic_cond_read_acquire(&lock->val, + !(VAL & _Q_LOCKED_MASK)); } /* @@ -441,8 +441,8 @@ queue: * * The PV pv_wait_head_or_lock function, if active, will acquire * the lock and return a non-zero value. So we have to skip the - * smp_cond_load_acquire() call. As the next PV queue head hasn't been - * designated yet, there is no way for the locked value to become + * atomic_cond_read_acquire() call. As the next PV queue head hasn't + * been designated yet, there is no way for the locked value to become * _Q_SLOW_VAL. So both the set_locked() and the * atomic_cmpxchg_relaxed() calls will be safe. * @@ -452,7 +452,7 @@ queue: if ((val = pv_wait_head_or_lock(lock, node))) goto locked; - val = smp_cond_load_acquire(&lock->val.counter, !(VAL & _Q_LOCKED_PENDING_MASK)); + val = atomic_cond_read_acquire(&lock->val, !(VAL & _Q_LOCKED_PENDING_MASK)); locked: /* @@ -469,7 +469,7 @@ locked: /* In the PV case we might already have _Q_LOCKED_VAL set */ if ((val & _Q_TAIL_MASK) == tail) { /* - * The smp_cond_load_acquire() call above has provided the + * The atomic_cond_read_acquire() call above has provided the * necessary acquire semantics required for locking. */ old = atomic_cmpxchg_relaxed(&lock->val, val, _Q_LOCKED_VAL);