Wan-Teh Chang
2170017a1c
avutil: fix data race in av_get_cpu_flags() ...
Make the one-time initialization in av_get_cpu_flags() thread-safe. The
static variables |flags|, |cpuflags_mask|, and |checked| in
libavutil/cpu.c are read and written using normal load and store
operations. These are considered as data races. The fix is to use atomic
load and store operations.
Remove the |checked| variable because the invalid value of -1 for
|flags| can be used to indicate the same condition. Rename |flags| to
|cpu_flags| and move it to file scope.
The fix can be verified by running the libavutil/tests/cpu_init.c test
program under ThreadSanitizer:
./configure --toolchain=clang-tsan
make libavutil/tests/cpu_init
libavutil/tests/cpu_init
There should be no warnings from ThreadSanitizer.
Co-author: Dmitry Vyukov of Google, who suggested the data race fix.
Signed-off-by: Wan-Teh Chang <wtc@google.com>
2016-12-08 15:53:58 -05:00
2016-11-10 11:06:08 +02:00
2016-11-24 21:26:22 +01:00
2016-05-04 18:16:21 +02:00
2015-09-29 11:10:37 +02:00
2015-05-31 12:07:11 +02:00
2016-12-08 15:53:58 -05:00
2016-11-03 17:43:55 +01:00
2016-05-13 14:55:56 +02:00
2016-04-07 16:14:42 +02:00
2016-04-07 16:14:42 +02:00
2015-08-28 16:04:27 +02:00
2016-07-21 12:52:19 +03:00
2016-10-27 12:21:46 +02:00
2016-05-04 18:16:21 +02:00
2016-04-07 16:14:42 +02:00
2015-10-03 13:45:37 +02:00
2016-12-07 14:26:21 -05:00
2016-04-07 16:14:42 +02:00
2016-04-07 16:14:42 +02:00
2015-07-31 09:04:09 +02:00
2016-10-02 18:58:04 +02:00
2016-10-02 18:58:04 +02:00
2016-08-11 10:29:23 +02:00
2015-08-23 21:44:38 +02:00
2015-08-23 21:44:38 +02:00
2016-05-10 11:30:25 +02:00
2016-01-11 15:32:56 -05:00
2015-05-31 12:07:11 +02:00
2016-12-08 15:53:58 -05:00
2016-12-08 15:53:58 -05:00
2016-04-07 16:14:42 +02:00
2016-05-13 14:55:56 +02:00
2015-08-31 17:06:32 +02:00
2015-10-12 13:35:01 +02:00
2016-05-04 18:16:21 +02:00
2015-03-23 20:53:28 +00:00
2016-12-07 14:26:21 -05:00
2016-04-07 16:14:42 +02:00
2016-04-07 16:14:42 +02:00
2015-02-14 10:13:49 -08:00
2016-04-07 16:14:42 +02:00
2016-06-21 19:54:42 +02:00
2016-12-07 14:32:17 -05:00
2016-04-07 16:14:42 +02:00
2015-07-29 22:09:16 +03:00
2016-09-22 09:47:48 +02:00
2016-02-14 22:08:33 +01:00
2016-11-18 10:31:53 +01:00
2016-05-17 09:11:25 +02:00
2016-11-03 23:49:01 +00:00
2016-11-07 12:47:40 +01:00
2016-06-21 19:53:37 +02:00
2016-11-26 18:03:05 +00:00
2016-10-02 11:41:45 +02:00
2016-09-14 20:48:36 +01:00
2016-02-14 22:06:04 +01:00
2016-11-03 23:49:01 +00:00
2016-11-21 14:29:11 +01:00
2016-08-31 08:15:47 +02:00
2016-08-31 08:15:47 +02:00
2016-11-21 14:29:10 +01:00
2016-08-03 10:56:52 +02:00
2016-08-02 21:18:18 +03:00
2016-04-07 16:14:42 +02:00
2016-05-29 16:43:11 +02:00
2016-04-07 16:14:42 +02:00
2015-12-14 16:16:55 +01:00
2015-04-20 19:20:57 +01:00
2015-04-19 12:41:59 +01:00
2015-12-14 16:16:55 +01:00
2016-12-08 15:53:58 -05:00
2016-08-17 12:16:42 +02:00
2016-05-04 18:16:21 +02:00
2015-08-28 16:04:27 +02:00
2016-09-03 15:11:29 +02:00
2016-07-21 12:52:19 +03:00
2016-11-03 20:17:12 +01:00
2016-05-04 18:16:21 +02:00
2016-04-07 16:14:42 +02:00
2015-04-07 12:36:11 +02:00
2016-11-08 11:22:29 -05:00
2016-01-25 12:02:20 -05:00
2016-12-02 11:36:46 -05:00
2016-05-04 18:16:21 +02:00
2015-07-31 09:04:12 +02:00
2015-07-31 09:04:12 +02:00
2016-02-18 15:35:30 +01:00
2016-02-18 15:35:30 +01:00
2016-04-07 16:14:42 +02:00
2015-08-28 16:04:27 +02:00
2016-12-07 14:32:17 -05:00
2016-12-08 20:12:23 +01:00
2016-05-17 12:25:27 -04:00
2016-12-07 14:26:21 -05:00
2015-10-14 14:35:34 +02:00
2015-12-14 16:42:35 +01:00
2016-04-07 16:14:42 +02:00
2015-08-28 16:04:27 +02:00
2015-07-02 23:22:53 +02:00
2016-12-07 14:34:34 -05:00
2016-04-07 16:14:42 +02:00
2015-11-13 21:53:54 +02:00
2170017a1c