diff options
| author | Ingo Molnar <mingo@elte.hu> | 2008-12-31 08:31:57 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-12-31 08:31:57 +0100 |
| commit | a9de18eb761f7c1c860964b2e5addc1a35c7e861 (patch) | |
| tree | 886e75fdfd09690cd262ca69cb7f5d1d42b48602 /arch/x86/kernel/tsc_sync.c | |
| parent | b2aaf8f74cdc84a9182f6cabf198b7763bcb9d40 (diff) | |
| parent | 6a94cb73064c952255336cc57731904174b2c58f (diff) | |
Merge branch 'linus' into stackprotector
Conflicts:
arch/x86/include/asm/pda.h
kernel/fork.c
Diffstat (limited to 'arch/x86/kernel/tsc_sync.c')
| -rw-r--r-- | arch/x86/kernel/tsc_sync.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/arch/x86/kernel/tsc_sync.c b/arch/x86/kernel/tsc_sync.c index 9ffb01c31c40..bf36328f6ef9 100644 --- a/arch/x86/kernel/tsc_sync.c +++ b/arch/x86/kernel/tsc_sync.c @@ -46,7 +46,9 @@ static __cpuinit void check_tsc_warp(void) cycles_t start, now, prev, end; int i; + rdtsc_barrier(); start = get_cycles(); + rdtsc_barrier(); /* * The measurement runs for 20 msecs: */ @@ -61,7 +63,9 @@ static __cpuinit void check_tsc_warp(void) */ __raw_spin_lock(&sync_lock); prev = last_tsc; + rdtsc_barrier(); now = get_cycles(); + rdtsc_barrier(); last_tsc = now; __raw_spin_unlock(&sync_lock); @@ -108,6 +112,12 @@ void __cpuinit check_tsc_sync_source(int cpu) if (unsynchronized_tsc()) return; + if (boot_cpu_has(X86_FEATURE_TSC_RELIABLE)) { + printk(KERN_INFO + "Skipping synchronization checks as TSC is reliable.\n"); + return; + } + printk(KERN_INFO "checking TSC synchronization [CPU#%d -> CPU#%d]:", smp_processor_id(), cpu); @@ -161,7 +171,7 @@ void __cpuinit check_tsc_sync_target(void) { int cpus = 2; - if (unsynchronized_tsc()) + if (unsynchronized_tsc() || boot_cpu_has(X86_FEATURE_TSC_RELIABLE)) return; /* |