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| author | Waiman Long <Waiman.Long@hpe.com> | 2015-12-10 21:17:45 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2016-02-29 10:02:42 +0100 |
| commit | 32d62510f949d3c8e83b9b3b844a84446611661b (patch) | |
| tree | fd97c000d107276754eca8f522d0a6f818c6e257 /kernel/locking/qspinlock_paravirt.h | |
| parent | locking/qspinlock: Use smp_cond_acquire() in pending code (diff) | |
| download | linux-32d62510f949d3c8e83b9b3b844a84446611661b.tar.xz linux-32d62510f949d3c8e83b9b3b844a84446611661b.zip | |
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>
Diffstat (limited to 'kernel/locking/qspinlock_paravirt.h')
| -rw-r--r-- | kernel/locking/qspinlock_paravirt.h | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/kernel/locking/qspinlock_paravirt.h b/kernel/locking/qspinlock_paravirt.h index 78f04a232d3a..21ede57f68b3 100644 --- a/kernel/locking/qspinlock_paravirt.h +++ b/kernel/locking/qspinlock_paravirt.h @@ -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 |