Merge branch 'rickard/win-cs-mutex/OTP-9671'

* rickard/win-cs-mutex/OTP-9671:
  Use critical sections as mutex implementation on Windows

3 files changed, 28 insertions, 2 deletions

diff --git a/erts/emulator/beam/erl_drv_thread.c b/erts/emulator/beam/erl_drv_thread.c
index dc578f6d2a..a49a155701 100644
--- a/erts/emulator/beam/erl_drv_thread.c
+++ b/erts/emulator/beam/erl_drv_thread.c
@@ -158,7 +158,9 @@ erl_drv_mutex_create(char *name)
 				       (sizeof(ErlDrvMutex)
 					+ (name ? sys_strlen(name) + 1 : 0)));
     if (dmtx) {
-	if (ethr_mutex_init(&dmtx->mtx) != 0) {
+	ethr_mutex_opt opt = ETHR_MUTEX_OPT_DEFAULT_INITER;
+	opt.posix_compliant = 1;
+	if (ethr_mutex_init_opt(&dmtx->mtx, &opt) != 0) {
 	    erts_free(ERTS_ALC_T_DRV_MTX, (void *) dmtx);
 	    dmtx = NULL;
 	}
@@ -226,7 +228,9 @@ erl_drv_cond_create(char *name)
 				      (sizeof(ErlDrvCond)
 				       + (name ? sys_strlen(name) + 1 : 0)));
     if (dcnd) {
-	if (ethr_cond_init(&dcnd->cnd) != 0) {
+	ethr_cond_opt opt = ETHR_COND_OPT_DEFAULT_INITER;
+	opt.posix_compliant = 1;
+	if (ethr_cond_init_opt(&dcnd->cnd, &opt) != 0) {
 	    erts_free(ERTS_ALC_T_DRV_CND, (void *) dcnd);
 	    dcnd = NULL;
 	}
diff --git a/erts/emulator/beam/erl_smp.h b/erts/emulator/beam/erl_smp.h
index a89ddfbcc1..63179dfad4 100644
--- a/erts/emulator/beam/erl_smp.h
+++ b/erts/emulator/beam/erl_smp.h
@@ -822,6 +822,16 @@ erts_smp_cnd_wait(erts_smp_cnd_t *cnd, erts_smp_mtx_t *mtx)
 #endif
 }
 
+/*
+ * IMPORTANT note about erts_smp_cnd_signal() and erts_smp_cnd_broadcast()
+ *
+ * POSIX allow a call to `pthread_cond_signal' or `pthread_cond_broadcast'
+ * even though the associated mutex/mutexes isn't/aren't locked by the
+ * caller. Our implementation do not allow that in order to avoid a
+ * performance penalty. That is, all associated mutexes *need* to be
+ * locked by the caller of erts_smp_cnd_signal()/erts_smp_cnd_broadcast()!
+ */
+
 ERTS_GLB_INLINE void
 erts_smp_cnd_signal(erts_smp_cnd_t *cnd)
 {
diff --git a/erts/emulator/beam/erl_threads.h b/erts/emulator/beam/erl_threads.h
index b4b6d0dfd5..065e7077c0 100644
--- a/erts/emulator/beam/erl_threads.h
+++ b/erts/emulator/beam/erl_threads.h
@@ -92,6 +92,8 @@ typedef struct {
 #endif
 } erts_rwmtx_t;
 
+#define ERTS_MTX_OPT_DEFAULT_INITER ETHR_MUTEX_OPT_DEFAULT_INITER
+#define ERTS_CND_OPT_DEFAULT_INITER ETHR_COND_OPT_DEFAULT_INITER
 #define ERTS_RWMTX_OPT_DEFAULT_INITER ETHR_RWMUTEX_OPT_DEFAULT_INITER
 #define ERTS_RWMTX_TYPE_NORMAL ETHR_RWMUTEX_TYPE_NORMAL
 #define ERTS_RWMTX_TYPE_FREQUENT_READ ETHR_RWMUTEX_TYPE_FREQUENT_READ
@@ -1130,6 +1132,16 @@ erts_cnd_wait(erts_cnd_t *cnd, erts_mtx_t *mtx)
 #endif
 }
 
+/*
+ * IMPORTANT note about erts_cnd_signal() and erts_cnd_broadcast()
+ *
+ * POSIX allow a call to `pthread_cond_signal' or `pthread_cond_broadcast'
+ * even though the associated mutex/mutexes isn't/aren't locked by the
+ * caller. Our implementation do not allow that in order to avoid a
+ * performance penalty. That is, all associated mutexes *need* to be
+ * locked by the caller of erts_cnd_signal()/erts_cnd_broadcast()!
+ */
+
 ERTS_GLB_INLINE void
 erts_cnd_signal(erts_cnd_t *cnd)
 {