Merge commit 'd1a6cb195f610978ba5d2351e60f938f7f261d59'

* commit 'd1a6cb195f610978ba5d2351e60f938f7f261d59': x86: Serialize rdtsc in read_time() Merged-by: Michael Niedermayer <michaelni@gmx.at>
2015-07-09 12:27:55 +02:00 · 2015-07-09 12:27:55 +02:00 · 2ecbf44f21
parent 7e85727b98 d1a6cb195f
commit 2ecbf44f21
1 changed files with 6 additions and 1 deletions
--- a/libavutil/x86/timer.h
+++ b/libavutil/x86/timer.h
@ -31,7 +31,12 @@
 static inline uint64_t read_time(void)
 {
    uint32_t a, d;
-    __asm__ volatile("rdtsc" : "=a" (a), "=d" (d));
+    __asm__ volatile(
+#if ARCH_X86_64 || defined(__SSE2__)
+                     "lfence \n\t"
+#endif
+                     "rdtsc  \n\t"
+                     : "=a" (a), "=d" (d));
    return ((uint64_t)d << 32) + a;
 }