Replace spinlock with mutex as pix_lock implementation

The spinlocks used implementing pix-locks have been replaced with
mutexes since they perform better during heavy contention.

2 files changed, 8 insertions, 8 deletions

diff --git a/erts/emulator/beam/erl_process_lock.c b/erts/emulator/beam/erl_process_lock.c
index 83379d7352..da97523dd0 100644
--- a/erts/emulator/beam/erl_process_lock.c
+++ b/erts/emulator/beam/erl_process_lock.c
@@ -123,10 +123,10 @@ erts_init_proc_lock(int cpus)
     erts_smp_spinlock_init(&qs_lock, "proc_lck_qs_alloc");
     for (i = 0; i < ERTS_NO_OF_PIX_LOCKS; i++) {
 #ifdef ERTS_ENABLE_LOCK_COUNT
-	erts_smp_spinlock_init_x(&erts_pix_locks[i].u.spnlck,
-				 "pix_lock", make_small(i));
+	erts_mtx_init_x(&erts_pix_locks[i].u.mtx,
+			"pix_lock", make_small(i));
 #else
-	erts_smp_spinlock_init(&erts_pix_locks[i].u.spnlck, "pix_lock");
+	erts_mtx_init(&erts_pix_locks[i].u.mtx, "pix_lock");
 #endif
     }
     queue_free_list = NULL;
diff --git a/erts/emulator/beam/erl_process_lock.h b/erts/emulator/beam/erl_process_lock.h
index 97f250138e..97e554914e 100644
--- a/erts/emulator/beam/erl_process_lock.h
+++ b/erts/emulator/beam/erl_process_lock.h
@@ -255,8 +255,8 @@ void erts_proc_lc_unrequire_lock(Process *p, ErtsProcLocks locks);
 
 typedef struct {
     union {
-	erts_smp_spinlock_t spnlck;
-	char buf[64]; /* Try to get locks in different cache lines */
+	erts_mtx_t mtx;
+	char buf[ERTS_ALC_CACHE_LINE_ALIGN_SIZE(sizeof(erts_mtx_t))];
     } u;
 } erts_pix_lock_t;
 
@@ -380,18 +380,18 @@ ERTS_GLB_INLINE void erts_proc_lock_op_debug(Process *, ErtsProcLocks, int);
 ERTS_GLB_INLINE void erts_pix_lock(erts_pix_lock_t *pixlck)
 {
     ERTS_LC_ASSERT(pixlck);
-    erts_smp_spin_lock(&pixlck->u.spnlck);
+    erts_mtx_lock(&pixlck->u.mtx);
 }
 
 ERTS_GLB_INLINE void erts_pix_unlock(erts_pix_lock_t *pixlck)
 {
     ERTS_LC_ASSERT(pixlck);
-    erts_smp_spin_unlock(&pixlck->u.spnlck);
+    erts_mtx_unlock(&pixlck->u.mtx);
 }
 
 ERTS_GLB_INLINE int erts_lc_pix_lock_is_locked(erts_pix_lock_t *pixlck)
 {
-    return erts_smp_lc_spinlock_is_locked(&pixlck->u.spnlck);
+    return erts_lc_mtx_is_locked(&pixlck->u.mtx);
 }
 
 /*