On bare metail, the pvqspinlock event counts will always be 0. So there
is no point in showing their corresponding debugfs files. So they are
skipped in this case.
Signed-off-by: Waiman Long <long...@redhat.com>
Acked-by: Davidlohr Bueso <dbu...@suse.de>
---
kernel/locking/lock_events.c | 28 +++++++++++++++++++++++++++-
1 file changed, 27 insertions(+), 1 deletion(-)
diff --git a/kernel/locking/lock_events.c b/kernel/locking/lock_events.c
index 71c36d1fb834..fa2c2f951c6b 100644
--- a/kernel/locking/lock_events.c
+++ b/kernel/locking/lock_events.c
@@ -115,6 +115,29 @@ static const struct file_operations fops_lockevent = {
.llseek = default_llseek,
};
+#ifdef CONFIG_PARAVIRT_SPINLOCKS
+#include <asm/paravirt.h>
+
+static bool __init skip_lockevent(const char *name)
+{
+ static int pv_on __initdata = -1;
+
+ if (pv_on < 0)
+ pv_on = !pv_is_native_spin_unlock();
+ /*
+ * Skip PV qspinlock events on bare metal.
+ */
+ if (!pv_on && !memcmp(name, "pv_", 3))
+ return true;
+ return false;
+}
+#else
+static inline bool skip_lockevent(const char *name)
+{
+ return false;
+}
+#endif
+
/*
* Initialize debugfs for the locking event counts.
*/
@@ -133,10 +156,13 @@ static int __init init_lockevent_counts(void)
* root is allowed to do the read/write to limit impact to system
* performance.
*/
- for (i = 0; i < lockevent_num; i++)
+ for (i = 0; i < lockevent_num; i++) {
+ if (skip_lockevent(lockevent_names[i]))
+ continue;
if (!debugfs_create_file(lockevent_names[i], 0400, d_counts,
(void *)(long)i, &fops_lockevent))
goto fail_undo;
+ }
if (!debugfs_create_file(lockevent_names[LOCKEVENT_reset_cnts], 0200,
d_counts, (void *)(long)LOCKEVENT_reset_cnts,
--
2.18.1
