From 2b953a5e994ce279904ec70220f7d4f31d380a0a Mon Sep 17 00:00:00 2001 From: Boris Ostrovsky Date: Tue, 28 Apr 2015 18:46:20 -0400 Subject: [PATCH] xen: Suspend ticks on all CPUs during suspend Commit 77e32c89a711 ("clockevents: Manage device's state separately for the core") decouples clockevent device's modes from states. With this change when a Xen guest tries to resume, it won't be calling its set_mode op which needs to be done on each VCPU in order to make the hypervisor aware that we are in oneshot mode. This happens because clockevents_tick_resume() (which is an intermediate step of resuming ticks on a processor) doesn't call clockevents_set_state() anymore and because during suspend clockevent devices on all VCPUs (except for the one doing the suspend) are left in ONESHOT state. As result, during resume the clockevents state machine will assume that device is already where it should be and doesn't need to be updated. To avoid this problem we should suspend ticks on all VCPUs during suspend. Signed-off-by: Boris Ostrovsky Signed-off-by: David Vrabel --- arch/x86/xen/suspend.c | 10 ++++++++++ drivers/xen/manage.c | 9 ++++++--- include/xen/xen-ops.h | 1 + 3 files changed, 17 insertions(+), 3 deletions(-) diff --git a/arch/x86/xen/suspend.c b/arch/x86/xen/suspend.c index d9497698645a..53b4c0811f4f 100644 --- a/arch/x86/xen/suspend.c +++ b/arch/x86/xen/suspend.c @@ -88,7 +88,17 @@ static void xen_vcpu_notify_restore(void *data) tick_resume_local(); } +static void xen_vcpu_notify_suspend(void *data) +{ + tick_suspend_local(); +} + void xen_arch_resume(void) { on_each_cpu(xen_vcpu_notify_restore, NULL, 1); } + +void xen_arch_suspend(void) +{ + on_each_cpu(xen_vcpu_notify_suspend, NULL, 1); +} diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c index bf1940706422..9e6a85104a20 100644 --- a/drivers/xen/manage.c +++ b/drivers/xen/manage.c @@ -131,6 +131,8 @@ static void do_suspend(void) goto out_resume; } + xen_arch_suspend(); + si.cancelled = 1; err = stop_machine(xen_suspend, &si, cpumask_of(0)); @@ -148,11 +150,12 @@ static void do_suspend(void) si.cancelled = 1; } + xen_arch_resume(); + out_resume: - if (!si.cancelled) { - xen_arch_resume(); + if (!si.cancelled) xs_resume(); - } else + else xs_suspend_cancel(); dpm_resume_end(si.cancelled ? PMSG_THAW : PMSG_RESTORE); diff --git a/include/xen/xen-ops.h b/include/xen/xen-ops.h index c643e6a94c9a..0ce4f32017ea 100644 --- a/include/xen/xen-ops.h +++ b/include/xen/xen-ops.h @@ -13,6 +13,7 @@ void xen_arch_post_suspend(int suspend_cancelled); void xen_timer_resume(void); void xen_arch_resume(void); +void xen_arch_suspend(void); void xen_resume_notifier_register(struct notifier_block *nb); void xen_resume_notifier_unregister(struct notifier_block *nb); -- 2.30.2