locking/pvqspinlock: Enable slowpath locking count tracking
This patch enables the tracking of the number of slowpath locking operations performed. This can be used to compare against the number of lock stealing operations to see what percentage of locks are stolen versus acquired via the regular slowpath. Signed-off-by: Waiman Long <Waiman.Long@hpe.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Douglas Hatch <doug.hatch@hpe.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Scott J Norton <scott.norton@hpe.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1449778666-13593-2-git-send-email-Waiman.Long@hpe.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
parent
cb037fdad6
commit
32d62510f9
|
@ -400,6 +400,11 @@ pv_wait_head_or_lock(struct qspinlock *lock, struct mcs_spinlock *node)
|
|||
if (READ_ONCE(pn->state) == vcpu_hashed)
|
||||
lp = (struct qspinlock **)1;
|
||||
|
||||
/*
|
||||
* Tracking # of slowpath locking operations
|
||||
*/
|
||||
qstat_inc(qstat_pv_lock_slowpath, true);
|
||||
|
||||
for (;; waitcnt++) {
|
||||
/*
|
||||
* Set correct vCPU state to be used by queue node wait-early
|
||||
|
|
|
@ -22,6 +22,7 @@
|
|||
* 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
|
||||
* pv_wait_again - # of vCPU wait's that happened after a vCPU kick
|
||||
|
@ -45,6 +46,7 @@ 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,
|
||||
|
@ -70,6 +72,7 @@ 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",
|
||||
|
|
Loading…
Reference in New Issue