@@ -12,11 +12,11 @@
* GNU General Public License for more details.
*
* (C) Copyright 2013-2015 Hewlett-Packard Development Company, L.P.
- * (C) Copyright 2013-2014 Red Hat, Inc.
+ * (C) Copyright 2013-2014,2018 Red Hat, Inc.
* (C) Copyright 2015 Intel Corp.
* (C) Copyright 2015 Hewlett-Packard Enterprise Development LP
*
- * Authors: Waiman Long <waiman.long@hpe.com>
+ * Authors: Waiman Long <longman@redhat.com>
* Peter Zijlstra <peterz@infradead.org>
*/
@@ -33,6 +33,11 @@
#include <asm/qspinlock.h>
/*
+ * Include queued spinlock statistics code
+ */
+#include "qspinlock_stat.h"
+
+/*
* The basic principle of a queue-based spinlock can best be understood
* by studying a classic queue-based spinlock implementation called the
* MCS lock. The paper below provides a good description for this kind
@@ -295,7 +300,7 @@ void queued_spin_lock_slowpath(struct qspinlock *lock, u32 val)
BUILD_BUG_ON(CONFIG_NR_CPUS >= (1U << _Q_TAIL_CPU_BITS));
if (pv_enabled())
- goto queue;
+ goto pv_queue;
if (virt_spin_lock(lock))
return;
@@ -348,6 +353,7 @@ void queued_spin_lock_slowpath(struct qspinlock *lock, u32 val)
* *,1,0 -> *,0,1
*/
clear_pending_set_locked(lock);
+ qstat_inc(qstat_lock_pending, true);
return;
}
@@ -363,6 +369,8 @@ void queued_spin_lock_slowpath(struct qspinlock *lock, u32 val)
* queuing.
*/
queue:
+ qstat_inc(qstat_lock_slowpath, true);
+pv_queue:
node = this_cpu_ptr(&mcs_nodes[0]);
idx = node->count++;
tail = encode_tail(smp_processor_id(), idx);
@@ -56,11 +56,6 @@ struct pv_node {
};
/*
- * Include queued spinlock statistics code
- */
-#include "qspinlock_stat.h"
-
-/*
* Hybrid PV queued/unfair lock
*
* By replacing the regular queued_spin_trylock() with the function below,
@@ -428,7 +423,7 @@ pv_wait_head_or_lock(struct qspinlock *lock, struct mcs_spinlock *node)
/*
* Tracking # of slowpath locking operations
*/
- qstat_inc(qstat_pv_lock_slowpath, true);
+ qstat_inc(qstat_lock_slowpath, true);
for (;; waitcnt++) {
/*
@@ -22,13 +22,14 @@
* pv_kick_wake - # of vCPU kicks used for computing pv_latency_wake
* pv_latency_kick - average latency (ns) of vCPU kick operation
* pv_latency_wake - average latency (ns) from vCPU kick to wakeup
- * pv_lock_slowpath - # of locking operations via the slowpath
* pv_lock_stealing - # of lock stealing operations
* pv_spurious_wakeup - # of spurious wakeups in non-head vCPUs
* pv_wait_again - # of wait's after a queue head vCPU kick
* pv_wait_early - # of early vCPU wait's
* pv_wait_head - # of vCPU wait's at the queue head
* pv_wait_node - # of vCPU wait's at a non-head queue node
+ * lock_pending - # of locking operations via pending code
+ * lock_slowpath - # of locking operations via MCS lock queue
*
* Writing to the "reset_counters" file will reset all the above counter
* values.
@@ -46,13 +47,14 @@ enum qlock_stats {
qstat_pv_kick_wake,
qstat_pv_latency_kick,
qstat_pv_latency_wake,
- qstat_pv_lock_slowpath,
qstat_pv_lock_stealing,
qstat_pv_spurious_wakeup,
qstat_pv_wait_again,
qstat_pv_wait_early,
qstat_pv_wait_head,
qstat_pv_wait_node,
+ qstat_lock_pending,
+ qstat_lock_slowpath,
qstat_num, /* Total number of statistical counters */
qstat_reset_cnts = qstat_num,
};
@@ -73,12 +75,13 @@ static const char * const qstat_names[qstat_num + 1] = {
[qstat_pv_spurious_wakeup] = "pv_spurious_wakeup",
[qstat_pv_latency_kick] = "pv_latency_kick",
[qstat_pv_latency_wake] = "pv_latency_wake",
- [qstat_pv_lock_slowpath] = "pv_lock_slowpath",
[qstat_pv_lock_stealing] = "pv_lock_stealing",
[qstat_pv_wait_again] = "pv_wait_again",
[qstat_pv_wait_early] = "pv_wait_early",
[qstat_pv_wait_head] = "pv_wait_head",
[qstat_pv_wait_node] = "pv_wait_node",
+ [qstat_lock_pending] = "lock_pending",
+ [qstat_lock_slowpath] = "lock_slowpath",
[qstat_reset_cnts] = "reset_counters",
};