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

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

1 files changed, 12 insertions, 0 deletions

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)
 {