Signed-off-by: Lai Jiangshan <[email protected]>
---
urcu-wait-lock-impl.h | 17 +++++++++++++++++
urcu/futex.h | 2 ++
2 files changed, 19 insertions(+), 0 deletions(-)
diff --git a/urcu-wait-lock-impl.h b/urcu-wait-lock-impl.h
index 88a21db..4cd70f2 100644
--- a/urcu-wait-lock-impl.h
+++ b/urcu-wait-lock-impl.h
@@ -22,6 +22,12 @@
#include <assert.h>
+#ifdef URCU_BOOST_READER
+#define urcu_boost_reader() (1)
+#else
+#define urcu_boost_reader() (0)
+#endif
+
static inline int32_t uwl_onwer(int32_t *lock)
{
return _CMM_LOAD_SHARED(*lock) & ~FUTEX_WAITERS;
@@ -54,6 +60,12 @@ static void uwl_lock(int32_t *lock, int32_t self)
return;
}
+ if (urcu_boost_reader()) {
+ if (futex_async(lock, FUTEX_LOCK_PI, 0, NULL, NULL, 0)
== 0)
+ return;
+ continue;
+ }
+
if ((o & FUTEX_WAITERS) == 0) {
if (uatomic_cmpxchg(lock, o, o | FUTEX_WAITERS) != o)
continue;
@@ -91,6 +103,11 @@ static int uwl_try_unlock(int32_t *lock, int32_t self)
static void uwl_slow_unlock(int32_t *lock)
{
+ if (urcu_boost_reader()) {
+ futex_async(lock, FUTEX_UNLOCK_PI, 0, NULL, NULL, 0);
+ return;
+ }
+
uwl_set_unlock(lock);
futex_async(lock, FUTEX_WAKE, 1, NULL, NULL, 0);
}
diff --git a/urcu/futex.h b/urcu/futex.h
index e47c307..cbcd967 100644
--- a/urcu/futex.h
+++ b/urcu/futex.h
@@ -30,6 +30,8 @@ extern "C" {
#define FUTEX_WAIT 0
#define FUTEX_WAKE 1
+#define FUTEX_LOCK_PI 6
+#define FUTEX_UNLOCK_PI 7
#define FUTEX_WAITERS 0x80000000
--
1.7.4.4
_______________________________________________
ltt-dev mailing list
[email protected]
http://lists.casi.polymtl.ca/cgi-bin/mailman/listinfo/ltt-dev
