Commit f2f09a4c authored by Christian Borntraeger's avatar Christian Borntraeger Committed by Ingo Molnar

locking/core: Remove cpu_relax_lowlatency() users

With the s390 special case of a yielding cpu_relax() implementation gone,
we can now remove all users of cpu_relax_lowlatency() and replace them
with cpu_relax().
Signed-off-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1477386195-32736-5-git-send-email-borntraeger@de.ibm.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 22b6430d
......@@ -723,7 +723,7 @@ bool __i915_spin_request(const struct drm_i915_gem_request *req,
if (busywait_stop(timeout_us, cpu))
break;
cpu_relax_lowlatency();
cpu_relax();
} while (!need_resched());
return false;
......
......@@ -342,7 +342,7 @@ static int vhost_net_tx_get_vq_desc(struct vhost_net *net,
endtime = busy_clock() + vq->busyloop_timeout;
while (vhost_can_busy_poll(vq->dev, endtime) &&
vhost_vq_avail_empty(vq->dev, vq))
cpu_relax_lowlatency();
cpu_relax();
preempt_enable();
r = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov),
out_num, in_num, NULL, NULL);
......@@ -533,7 +533,7 @@ static int vhost_net_rx_peek_head_len(struct vhost_net *net, struct sock *sk)
while (vhost_can_busy_poll(&net->dev, endtime) &&
!sk_has_rx_data(sk) &&
vhost_vq_avail_empty(&net->dev, vq))
cpu_relax_lowlatency();
cpu_relax();
preempt_enable();
......
......@@ -28,7 +28,7 @@ struct mcs_spinlock {
#define arch_mcs_spin_lock_contended(l) \
do { \
while (!(smp_load_acquire(l))) \
cpu_relax_lowlatency(); \
cpu_relax(); \
} while (0)
#endif
......@@ -108,7 +108,7 @@ void mcs_spin_unlock(struct mcs_spinlock **lock, struct mcs_spinlock *node)
return;
/* Wait until the next pointer is set */
while (!(next = READ_ONCE(node->next)))
cpu_relax_lowlatency();
cpu_relax();
}
/* Pass lock to next waiter. */
......
......@@ -369,7 +369,7 @@ bool mutex_spin_on_owner(struct mutex *lock, struct task_struct *owner)
break;
}
cpu_relax_lowlatency();
cpu_relax();
}
rcu_read_unlock();
......@@ -492,7 +492,7 @@ static bool mutex_optimistic_spin(struct mutex *lock,
* memory barriers as we'll eventually observe the right
* values at the cost of a few extra spins.
*/
cpu_relax_lowlatency();
cpu_relax();
}
if (!waiter)
......
......@@ -75,7 +75,7 @@ osq_wait_next(struct optimistic_spin_queue *lock,
break;
}
cpu_relax_lowlatency();
cpu_relax();
}
return next;
......@@ -122,7 +122,7 @@ bool osq_lock(struct optimistic_spin_queue *lock)
if (need_resched())
goto unqueue;
cpu_relax_lowlatency();
cpu_relax();
}
return true;
......@@ -148,7 +148,7 @@ bool osq_lock(struct optimistic_spin_queue *lock)
if (smp_load_acquire(&node->locked))
return true;
cpu_relax_lowlatency();
cpu_relax();
/*
* Or we race against a concurrent unqueue()'s step-B, in which
......
......@@ -54,7 +54,7 @@ static __always_inline void
rspin_until_writer_unlock(struct qrwlock *lock, u32 cnts)
{
while ((cnts & _QW_WMASK) == _QW_LOCKED) {
cpu_relax_lowlatency();
cpu_relax();
cnts = atomic_read_acquire(&lock->cnts);
}
}
......@@ -130,7 +130,7 @@ void queued_write_lock_slowpath(struct qrwlock *lock)
(cmpxchg_relaxed(&l->wmode, 0, _QW_WAITING) == 0))
break;
cpu_relax_lowlatency();
cpu_relax();
}
/* When no more readers, set the locked flag */
......@@ -141,7 +141,7 @@ void queued_write_lock_slowpath(struct qrwlock *lock)
_QW_LOCKED) == _QW_WAITING))
break;
cpu_relax_lowlatency();
cpu_relax();
}
unlock:
arch_spin_unlock(&lock->wait_lock);
......
......@@ -368,7 +368,7 @@ static noinline bool rwsem_spin_on_owner(struct rw_semaphore *sem)
return false;
}
cpu_relax_lowlatency();
cpu_relax();
}
rcu_read_unlock();
out:
......@@ -423,7 +423,7 @@ static bool rwsem_optimistic_spin(struct rw_semaphore *sem)
* memory barriers as we'll eventually observe the right
* values at the cost of a few extra spins.
*/
cpu_relax_lowlatency();
cpu_relax();
}
osq_unlock(&sem->osq);
done:
......
......@@ -20,7 +20,7 @@
if (likely(old.lock_count == prev.lock_count)) { \
SUCCESS; \
} \
cpu_relax_lowlatency(); \
cpu_relax(); \
} \
} while (0)
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment