[waffle] [PATCH v3 2/3] wcore: rework non-compatible mutex initialization
Emil Velikov
emil.l.velikov at gmail.com
Fri Mar 27 16:28:37 PDT 2015
C11 does not specify a static initializer, based on the idea that the
a mutex will be platform and/or implementation dependent. As such the
alternative solution is to initialize the mutex with call_once/mtx_init.
This will allow us to remove the transition hack, and in due time move
to the system's C11 threads implementation.
v2: Actually use call_once() to prevent the possibility of multiple
threads hitting the mtx_init() at the same time. Suggested by Jose.
v3: Do not destroy the mutex. Suggested by Chad.
Cc: Jose Fonseca <jfonseca at vmware.com>
Signed-off-by: Emil Velikov <emil.l.velikov at gmail.com>
---
src/waffle/core/wcore_display.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/src/waffle/core/wcore_display.c b/src/waffle/core/wcore_display.c
index 2feeeba..40f98cf 100644
--- a/src/waffle/core/wcore_display.c
+++ b/src/waffle/core/wcore_display.c
@@ -29,16 +29,25 @@
#include "wcore_display.h"
+static mtx_t mutex;
+
+static void
+wcore_display_init_once(void)
+{
+ mtx_init(&mutex, mtx_plain);
+}
+
bool
wcore_display_init(struct wcore_display *self,
struct wcore_platform *platform)
{
static size_t id_counter = 0;
- static mtx_t mutex = _MTX_INITIALIZER_NP;
+ static once_flag flag = ONCE_FLAG_INIT;
assert(self);
assert(platform);
+ call_once(&flag, wcore_display_init_once);
mtx_lock(&mutex);
self->api.display_id = ++id_counter;
mtx_unlock(&mutex);
--
2.3.1
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