diff options
Diffstat (limited to 'arch/i386/xen/time.c')
| -rw-r--r-- | arch/i386/xen/time.c | 27 |
1 files changed, 26 insertions, 1 deletions
diff --git a/arch/i386/xen/time.c b/arch/i386/xen/time.c index acbfd996946..2aab44bec2a 100644 --- a/arch/i386/xen/time.c +++ b/arch/i386/xen/time.c @@ -28,6 +28,8 @@ #define TIMER_SLOP 100000 #define NS_PER_TICK (1000000000LL / HZ) +static cycle_t xen_clocksource_read(void); + /* These are perodically updated in shared_info, and then copied here. */ struct shadow_time_info { u64 tsc_timestamp; /* TSC at last update of time vals. */ @@ -169,6 +171,29 @@ static void do_stolen_accounting(void) account_steal_time(idle_task(smp_processor_id()), ticks); } +/* + * Xen sched_clock implementation. Returns the number of unstolen + * nanoseconds, which is nanoseconds the VCPU spent in RUNNING+BLOCKED + * states. + */ +unsigned long long xen_sched_clock(void) +{ + struct vcpu_runstate_info state; + cycle_t now = xen_clocksource_read(); + s64 offset; + + get_runstate_snapshot(&state); + + WARN_ON(state.state != RUNSTATE_running); + + offset = now - state.state_entry_time; + if (offset < 0) + offset = 0; + + return state.time[RUNSTATE_blocked] + + state.time[RUNSTATE_running] + + offset; +} /* Get the CPU speed from Xen */ @@ -261,7 +286,7 @@ static u64 get_nsec_offset(struct shadow_time_info *shadow) return scale_delta(delta, shadow->tsc_to_nsec_mul, shadow->tsc_shift); } -cycle_t xen_clocksource_read(void) +static cycle_t xen_clocksource_read(void) { struct shadow_time_info *shadow = &get_cpu_var(shadow_time); cycle_t ret; |