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authorIngo Molnar <mingo@kernel.org>2012-04-14 13:18:27 +0200
committerIngo Molnar <mingo@kernel.org>2012-04-14 13:19:04 +0200
commit6ac1ef482d7ae0c690f1640bf6eb818ff9a2d91e (patch)
tree021cc9f6b477146fcebe6f3be4752abfa2ba18a9 /arch/x86/kernel/tsc.c
parent682968e0c425c60f0dde37977e5beb2b12ddc4cc (diff)
parenta385ec4f11bdcf81af094c03e2444ee9b7fad2e5 (diff)
Merge branch 'perf/core' into perf/uprobes
Merge in latest upstream (and the latest perf development tree), to prepare for tooling changes, and also to pick up v3.4 MM changes that the uprobes code needs to take care of. Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/tsc.c')
-rw-r--r--arch/x86/kernel/tsc.c17
1 files changed, 14 insertions, 3 deletions
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index a62c201c97e..fc0a147e372 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -620,7 +620,8 @@ static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu)
if (cpu_khz) {
*scale = (NSEC_PER_MSEC << CYC2NS_SCALE_FACTOR)/cpu_khz;
- *offset = ns_now - (tsc_now * *scale >> CYC2NS_SCALE_FACTOR);
+ *offset = ns_now - mult_frac(tsc_now, *scale,
+ (1UL << CYC2NS_SCALE_FACTOR));
}
sched_clock_idle_wakeup_event(0);
@@ -629,7 +630,7 @@ static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu)
static unsigned long long cyc2ns_suspend;
-void save_sched_clock_state(void)
+void tsc_save_sched_clock_state(void)
{
if (!sched_clock_stable)
return;
@@ -645,7 +646,7 @@ void save_sched_clock_state(void)
* that sched_clock() continues from the point where it was left off during
* suspend.
*/
-void restore_sched_clock_state(void)
+void tsc_restore_sched_clock_state(void)
{
unsigned long long offset;
unsigned long flags;
@@ -932,6 +933,16 @@ static int __init init_tsc_clocksource(void)
clocksource_tsc.rating = 0;
clocksource_tsc.flags &= ~CLOCK_SOURCE_IS_CONTINUOUS;
}
+
+ /*
+ * Trust the results of the earlier calibration on systems
+ * exporting a reliable TSC.
+ */
+ if (boot_cpu_has(X86_FEATURE_TSC_RELIABLE)) {
+ clocksource_register_khz(&clocksource_tsc, tsc_khz);
+ return 0;
+ }
+
schedule_delayed_work(&tsc_irqwork, 0);
return 0;
}