diff options
| author | Christophe Fergeau <cfergeau@redhat.com> | 2013-04-10 13:59:34 +0200 |
|---|---|---|
| committer | Christophe Fergeau <cfergeau@redhat.com> | 2016-01-08 15:31:38 +0100 |
| commit | 6b86c1a510f333f53a6955cd09da16fd98731d02 (patch) | |
| tree | f8c35622162abf129c9d33668e2333f241678aff | |
| parent | cffb8baee117710087445c968acc55654f74f508 (diff) | |
Use gcc builtin rather than asm for memory barriers
This should make things more portable.
On my machine, __sync_synchronize() uses mfence rather than lock; addl;
Looking at the kernel memory barriers, this should be fine:
http://lxr.free-electrons.com/source/arch/x86/um/asm/barrier.h
The kernel favours using mfence, but falls back to lock; addl; when it's
not available (32 bit non-SSE machines).
https://bugs.freedesktop.org/show_bug.cgi?id=86997
| -rw-r--r-- | spice/barrier.h | 7 |
1 files changed, 1 insertions, 6 deletions
diff --git a/spice/barrier.h b/spice/barrier.h index 710da09..7d63721 100644 --- a/spice/barrier.h +++ b/spice/barrier.h @@ -34,12 +34,7 @@ #ifdef __GNUC__ -#ifdef __i386__ -#define spice_mb() __asm__ __volatile__ ("lock; addl $0,0(%%esp)": : :"memory") -#else -//mfence -#define spice_mb() __asm__ __volatile__ ("lock; addl $0,0(%%rsp)": : :"memory") -#endif +#define spice_mb() __sync_synchronize () #else |