[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-changelog] [xen-unstable] cpuidle: redirect some hpet lock users to a new cpumask_lock
# HG changeset patch # User Keir Fraser <keir.fraser@xxxxxxxxxx> # Date 1276761170 -3600 # Node ID d0ad966b3d1a8653e2d147baf2843f2ca5ea7aed # Parent 47655a695312af43c1dd163b22ab4adb02553f60 cpuidle: redirect some hpet lock users to a new cpumask_lock The hpet channel lock was also used for prevent handle_hpet_broadcast access other cpu's timer_deadline_start/end after other cpu was already waken up. This purpose can be approached via a standalone lock to remove much spins on the hpet channel lock. Signed-off-by: Wei Gang <gang.wei@xxxxxxxxx> --- xen/arch/x86/hpet.c | 11 +++++++---- 1 files changed, 7 insertions(+), 4 deletions(-) diff -r 47655a695312 -r d0ad966b3d1a xen/arch/x86/hpet.c --- a/xen/arch/x86/hpet.c Thu Jun 17 08:52:29 2010 +0100 +++ b/xen/arch/x86/hpet.c Thu Jun 17 08:52:50 2010 +0100 @@ -34,6 +34,7 @@ struct hpet_event_channel int shift; s_time_t next_event; cpumask_t cpumask; + spinlock_t cpumask_lock; spinlock_t lock; void (*event_handler)(struct hpet_event_channel *); @@ -196,7 +197,7 @@ again: /* find all expired events */ for_each_cpu_mask(cpu, ch->cpumask) { - spin_lock_irq(&ch->lock); + spin_lock_irq(&ch->cpumask_lock); if ( cpumask_test_cpu(cpu, ch->cpumask) ) { @@ -206,7 +207,7 @@ again: next_event = per_cpu(timer_deadline_end, cpu); } - spin_unlock_irq(&ch->lock); + spin_unlock_irq(&ch->cpumask_lock); } /* wakeup the cpus which have an expired event. */ @@ -579,6 +580,7 @@ void hpet_broadcast_init(void) hpet_events[i].next_event = STIME_MAX; hpet_events[i].event_handler = handle_hpet_broadcast; spin_lock_init(&hpet_events[i].lock); + spin_lock_init(&hpet_events[i].cpumask_lock); } return; @@ -613,6 +615,7 @@ void hpet_broadcast_init(void) legacy_hpet_event.idx = 0; legacy_hpet_event.flags = 0; spin_lock_init(&legacy_hpet_event.lock); + spin_lock_init(&legacy_hpet_event.cpumask_lock); if ( !force_hpet_broadcast ) pv_rtc_handler = handle_rtc_once; @@ -689,9 +692,9 @@ void hpet_broadcast_exit(void) if ( !reprogram_timer(this_cpu(timer_deadline_start)) ) raise_softirq(TIMER_SOFTIRQ); - spin_lock_irq(&ch->lock); + spin_lock_irq(&ch->cpumask_lock); cpu_clear(cpu, ch->cpumask); - spin_unlock_irq(&ch->lock); + spin_unlock_irq(&ch->cpumask_lock); if ( ch != &legacy_hpet_event ) { _______________________________________________ Xen-changelog mailing list Xen-changelog@xxxxxxxxxxxxxxxxxxx http://lists.xensource.com/xen-changelog
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