alistair23-linux/arch/x86/xen/suspend.c
Boris Ostrovsky 2b953a5e99 xen: Suspend ticks on all CPUs during suspend
Commit 77e32c89a7 ("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 <boris.ostrovsky@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-04-29 17:10:05 +01:00

105 lines
2.1 KiB
C

#include <linux/types.h>
#include <linux/tick.h>
#include <xen/interface/xen.h>
#include <xen/grant_table.h>
#include <xen/events.h>
#include <asm/xen/hypercall.h>
#include <asm/xen/page.h>
#include <asm/fixmap.h>
#include "xen-ops.h"
#include "mmu.h"
static void xen_pv_pre_suspend(void)
{
xen_mm_pin_all();
xen_start_info->store_mfn = mfn_to_pfn(xen_start_info->store_mfn);
xen_start_info->console.domU.mfn =
mfn_to_pfn(xen_start_info->console.domU.mfn);
BUG_ON(!irqs_disabled());
HYPERVISOR_shared_info = &xen_dummy_shared_info;
if (HYPERVISOR_update_va_mapping(fix_to_virt(FIX_PARAVIRT_BOOTMAP),
__pte_ma(0), 0))
BUG();
}
static void xen_hvm_post_suspend(int suspend_cancelled)
{
#ifdef CONFIG_XEN_PVHVM
int cpu;
xen_hvm_init_shared_info();
xen_callback_vector();
xen_unplug_emulated_devices();
if (xen_feature(XENFEAT_hvm_safe_pvclock)) {
for_each_online_cpu(cpu) {
xen_setup_runstate_info(cpu);
}
}
#endif
}
static void xen_pv_post_suspend(int suspend_cancelled)
{
xen_build_mfn_list_list();
xen_setup_shared_info();
if (suspend_cancelled) {
xen_start_info->store_mfn =
pfn_to_mfn(xen_start_info->store_mfn);
xen_start_info->console.domU.mfn =
pfn_to_mfn(xen_start_info->console.domU.mfn);
} else {
#ifdef CONFIG_SMP
BUG_ON(xen_cpu_initialized_map == NULL);
cpumask_copy(xen_cpu_initialized_map, cpu_online_mask);
#endif
xen_vcpu_restore();
}
xen_mm_unpin_all();
}
void xen_arch_pre_suspend(void)
{
if (xen_pv_domain())
xen_pv_pre_suspend();
}
void xen_arch_post_suspend(int cancelled)
{
if (xen_pv_domain())
xen_pv_post_suspend(cancelled);
else
xen_hvm_post_suspend(cancelled);
}
static void xen_vcpu_notify_restore(void *data)
{
/* Boot processor notified via generic timekeeping_resume() */
if (smp_processor_id() == 0)
return;
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);
}