[PATCH 2/4] Add functions to check if the host has stopped the vm
From: Eric B Munson <hidden>
Date: 2011-08-29 23:27:51
Also in:
linux-arch, lkml
Subsystem:
kvm paravirt (kvm/paravirt), the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Paolo Bonzini, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
When a host stops or suspends a VM it will set a flag to show this. The watchdog will use these functions to determine if a softlockup is real, or the result of a suspended VM. Signed-off-by: Eric B Munson <redacted> --- arch/x86/include/asm/pvclock.h | 2 ++ arch/x86/kernel/kvmclock.c | 14 ++++++++++++++ 2 files changed, 16 insertions(+), 0 deletions(-)
diff --git a/arch/x86/include/asm/pvclock.h b/arch/x86/include/asm/pvclock.h
index a518c0a..dd59ad0 100644
--- a/arch/x86/include/asm/pvclock.h
+++ b/arch/x86/include/asm/pvclock.h@@ -13,6 +13,8 @@ void pvclock_read_wallclock(struct pvclock_wall_clock *wall, struct timespec *ts); void pvclock_resume(void); +bool kvm_check_and_clear_host_stopped(int cpu); + /* * Scale a 64-bit delta by scaling and multiplying by a 32-bit fraction, * yielding a 64-bit result.
diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c
index c1a0188..5f60d2b 100644
--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c@@ -113,6 +113,20 @@ static void kvm_get_preset_lpj(void) preset_lpj = lpj; } +bool kvm_check_and_clear_host_stopped(int cpu) +{ + bool ret = false; + struct pvclock_vcpu_time_info *src; + + src = &per_cpu(hv_clock, cpu); + if ((src->flags & PVCLOCK_GUEST_STOPPED) != 0) { + src->flags = src->flags & (~PVCLOCK_GUEST_STOPPED); + ret = true; + } + + return ret; +} + static struct clocksource kvm_clock = { .name = "kvm-clock", .read = kvm_clock_get_cycles,
--
1.7.4.1