diff options
author | Russell King <rmk@dyn-67.arm.linux.org.uk> | 2009-03-28 20:29:51 +0000 |
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committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2009-03-28 20:29:51 +0000 |
commit | ed40d0c472b136682b2fcba05f89762859c7374f (patch) | |
tree | 076b83a26bcd63d6158463735dd34c10bbc591dc /kernel/sched_clock.c | |
parent | 9e495834e59ca9b29f1a1f63b9f5533bb022ac49 (diff) | |
parent | 5d80f8e5a9dc9c9a94d4aeaa567e219a808b8a4a (diff) |
Merge branch 'origin' into devel
Conflicts:
sound/soc/pxa/pxa2xx-i2s.c
Diffstat (limited to 'kernel/sched_clock.c')
-rw-r--r-- | kernel/sched_clock.c | 30 |
1 files changed, 17 insertions, 13 deletions
diff --git a/kernel/sched_clock.c b/kernel/sched_clock.c index a0b0852414c..390f33234bd 100644 --- a/kernel/sched_clock.c +++ b/kernel/sched_clock.c @@ -24,11 +24,11 @@ * The clock: sched_clock_cpu() is monotonic per cpu, and should be somewhat * consistent between cpus (never more than 2 jiffies difference). */ -#include <linux/sched.h> -#include <linux/percpu.h> #include <linux/spinlock.h> -#include <linux/ktime.h> #include <linux/module.h> +#include <linux/percpu.h> +#include <linux/ktime.h> +#include <linux/sched.h> /* * Scheduler clock - returns current time in nanosec units. @@ -43,6 +43,7 @@ unsigned long long __attribute__((weak)) sched_clock(void) static __read_mostly int sched_clock_running; #ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK +__read_mostly int sched_clock_stable; struct sched_clock_data { /* @@ -87,7 +88,7 @@ void sched_clock_init(void) } /* - * min,max except they take wrapping into account + * min, max except they take wrapping into account */ static inline u64 wrap_min(u64 x, u64 y) @@ -111,15 +112,13 @@ static u64 __update_sched_clock(struct sched_clock_data *scd, u64 now) s64 delta = now - scd->tick_raw; u64 clock, min_clock, max_clock; - WARN_ON_ONCE(!irqs_disabled()); - if (unlikely(delta < 0)) delta = 0; /* * scd->clock = clamp(scd->tick_gtod + delta, - * max(scd->tick_gtod, scd->clock), - * scd->tick_gtod + TICK_NSEC); + * max(scd->tick_gtod, scd->clock), + * scd->tick_gtod + TICK_NSEC); */ clock = scd->tick_gtod + delta; @@ -148,12 +147,13 @@ static void lock_double_clock(struct sched_clock_data *data1, u64 sched_clock_cpu(int cpu) { - struct sched_clock_data *scd = cpu_sdc(cpu); u64 now, clock, this_clock, remote_clock; + struct sched_clock_data *scd; - if (unlikely(!sched_clock_running)) - return 0ull; + if (sched_clock_stable) + return sched_clock(); + scd = cpu_sdc(cpu); WARN_ON_ONCE(!irqs_disabled()); now = sched_clock(); @@ -195,14 +195,18 @@ u64 sched_clock_cpu(int cpu) void sched_clock_tick(void) { - struct sched_clock_data *scd = this_scd(); + struct sched_clock_data *scd; u64 now, now_gtod; + if (sched_clock_stable) + return; + if (unlikely(!sched_clock_running)) return; WARN_ON_ONCE(!irqs_disabled()); + scd = this_scd(); now_gtod = ktime_to_ns(ktime_get()); now = sched_clock(); @@ -250,7 +254,7 @@ u64 sched_clock_cpu(int cpu) return sched_clock(); } -#endif +#endif /* CONFIG_HAVE_UNSTABLE_SCHED_CLOCK */ unsigned long long cpu_clock(int cpu) { |