From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric B Munson Subject: [PATCH 2/6] Add functions to check if the host has stopped the vm Date: Tue, 25 Oct 2011 15:26:15 -0400 Message-ID: <1319570779-8907-3-git-send-email-emunson@mgebm.net> References: <1319570779-8907-1-git-send-email-emunson@mgebm.net> Return-path: In-Reply-To: <1319570779-8907-1-git-send-email-emunson@mgebm.net> Sender: linux-kernel-owner@vger.kernel.org To: avi@redhat.com Cc: mingo@redhat.com, x86@kernel.org, hpa@zytor.com, mtosatti@redhat.com, arnd@arndb.de, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-arch@vger.kernel.org, ryanh@linux.vnet.ibm.com, aliguori@us.ibm.com, Eric B Munson List-Id: linux-arch.vger.kernel.org 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 --- arch/x86/include/asm/pvclock.h | 2 ++ arch/x86/kernel/kvmclock.c | 19 +++++++++++++++++++ 2 files changed, 21 insertions(+), 0 deletions(-) diff --git a/arch/x86/include/asm/pvclock.h b/arch/x86/include/asm/pvclock.h index c59cc97..7d3ba41 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..8ddcfaf 100644 --- a/arch/x86/kernel/kvmclock.c +++ b/arch/x86/kernel/kvmclock.c @@ -113,6 +113,25 @@ 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; + + /* + * per_cpu() is safe here because this function is only called from + * timer functions where preemption is already disabled. + */ + WARN_ON(!in_atomic()); + 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, -- 1.7.5.4 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from oz.csail.mit.edu ([128.30.30.239]:57248 "EHLO ozymandias.localdomain" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752934Ab1JYT0Z (ORCPT ); Tue, 25 Oct 2011 15:26:25 -0400 From: Eric B Munson Subject: [PATCH 2/6] Add functions to check if the host has stopped the vm Date: Tue, 25 Oct 2011 15:26:15 -0400 Message-ID: <1319570779-8907-3-git-send-email-emunson@mgebm.net> In-Reply-To: <1319570779-8907-1-git-send-email-emunson@mgebm.net> References: <1319570779-8907-1-git-send-email-emunson@mgebm.net> Sender: linux-arch-owner@vger.kernel.org List-ID: To: avi@redhat.com Cc: mingo@redhat.com, x86@kernel.org, hpa@zytor.com, mtosatti@redhat.com, arnd@arndb.de, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-arch@vger.kernel.org, ryanh@linux.vnet.ibm.com, aliguori@us.ibm.com, Eric B Munson Message-ID: <20111025192615.zyiRiZuR9RznobNkHGzq8rNKdbk7NCUEjgMIvCTSQRo@z> 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 --- arch/x86/include/asm/pvclock.h | 2 ++ arch/x86/kernel/kvmclock.c | 19 +++++++++++++++++++ 2 files changed, 21 insertions(+), 0 deletions(-) diff --git a/arch/x86/include/asm/pvclock.h b/arch/x86/include/asm/pvclock.h index c59cc97..7d3ba41 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..8ddcfaf 100644 --- a/arch/x86/kernel/kvmclock.c +++ b/arch/x86/kernel/kvmclock.c @@ -113,6 +113,25 @@ 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; + + /* + * per_cpu() is safe here because this function is only called from + * timer functions where preemption is already disabled. + */ + WARN_ON(!in_atomic()); + 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, -- 1.7.5.4