Commit 595dc54a authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'x86-vdso-for-linus' of...

Merge branch 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: move rdtsc_barrier() into the TSC vread method
parents 9b29e822 7d96fd41
...@@ -710,7 +710,16 @@ static cycle_t read_tsc(struct clocksource *cs) ...@@ -710,7 +710,16 @@ static cycle_t read_tsc(struct clocksource *cs)
#ifdef CONFIG_X86_64 #ifdef CONFIG_X86_64
static cycle_t __vsyscall_fn vread_tsc(void) static cycle_t __vsyscall_fn vread_tsc(void)
{ {
cycle_t ret = (cycle_t)vget_cycles(); cycle_t ret;
/*
* Surround the RDTSC by barriers, to make sure it's not
* speculated to outside the seqlock critical section and
* does not cause time warps:
*/
rdtsc_barrier();
ret = (cycle_t)vget_cycles();
rdtsc_barrier();
return ret >= __vsyscall_gtod_data.clock.cycle_last ? return ret >= __vsyscall_gtod_data.clock.cycle_last ?
ret : __vsyscall_gtod_data.clock.cycle_last; ret : __vsyscall_gtod_data.clock.cycle_last;
......
...@@ -132,15 +132,7 @@ static __always_inline void do_vgettimeofday(struct timeval * tv) ...@@ -132,15 +132,7 @@ static __always_inline void do_vgettimeofday(struct timeval * tv)
return; return;
} }
/*
* Surround the RDTSC by barriers, to make sure it's not
* speculated to outside the seqlock critical section and
* does not cause time warps:
*/
rdtsc_barrier();
now = vread(); now = vread();
rdtsc_barrier();
base = __vsyscall_gtod_data.clock.cycle_last; base = __vsyscall_gtod_data.clock.cycle_last;
mask = __vsyscall_gtod_data.clock.mask; mask = __vsyscall_gtod_data.clock.mask;
mult = __vsyscall_gtod_data.clock.mult; mult = __vsyscall_gtod_data.clock.mult;
......
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