[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-devel] [patch 20/33] xen: Implement xen_sched_clock
Implement xen_sched_clock, which returns the number of ns the current vcpu has been actually in an unstolen state (ie, running or blocked, vs runnable-but-not-running, or offline) since boot. Signed-off-by: Jeremy Fitzhardinge <jeremy@xxxxxxxxxxxxx> Acked-by: Chris Wright <chrisw@xxxxxxxxxxxx> Cc: john stultz <johnstul@xxxxxxxxxx> --- arch/i386/xen/enlighten.c | 2 +- arch/i386/xen/time.c | 27 ++++++++++++++++++++++++++- arch/i386/xen/xen-ops.h | 3 +-- 3 files changed, 28 insertions(+), 4 deletions(-) =================================================================== --- a/arch/i386/xen/enlighten.c +++ b/arch/i386/xen/enlighten.c @@ -679,7 +679,7 @@ static const struct paravirt_ops xen_par .set_wallclock = xen_set_wallclock, .get_wallclock = xen_get_wallclock, .get_cpu_khz = xen_cpu_khz, - .sched_clock = xen_clocksource_read, + .sched_clock = xen_sched_clock, .cpuid = xen_cpuid, =================================================================== --- a/arch/i386/xen/time.c +++ b/arch/i386/xen/time.c @@ -26,6 +26,8 @@ #define TIMER_SLOP 100000 /* Xen may fire a timer up to this many ns early */ #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 */ @@ -258,7 +283,7 @@ static u64 get_nsec_offset(struct 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; =================================================================== --- a/arch/i386/xen/xen-ops.h +++ b/arch/i386/xen/xen-ops.h @@ -2,7 +2,6 @@ #define XEN_OPS_H #include <linux/init.h> -#include <linux/clocksource.h> DECLARE_PER_CPU(struct vcpu_info *, xen_vcpu); DECLARE_PER_CPU(unsigned long, xen_cr3); @@ -18,7 +17,7 @@ void __init xen_time_init(void); void __init xen_time_init(void); unsigned long xen_get_wallclock(void); int xen_set_wallclock(unsigned long time); -cycle_t xen_clocksource_read(void); +unsigned long long xen_sched_clock(void); void xen_mark_init_mm_pinned(void); -- _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxxxxxxxx http://lists.xensource.com/xen-devel
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