From 692297d8f96887f836d9049a653ed05a71cf48fb Mon Sep 17 00:00:00 2001 From: Ulrich Obergfell Date: Tue, 14 Apr 2015 15:44:19 -0700 Subject: [PATCH] watchdog: introduce the hardlockup_detector_disable() function Have kvm_guest_init() use hardlockup_detector_disable() instead of watchdog_enable_hardlockup_detector(false). Remove the watchdog_hardlockup_detector_is_enabled() and the watchdog_enable_hardlockup_detector() function which are no longer needed. Signed-off-by: Ulrich Obergfell Signed-off-by: Don Zickus Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/x86/kernel/kvm.c | 2 +- include/linux/nmi.h | 9 ++------- kernel/watchdog.c | 21 ++------------------- 3 files changed, 5 insertions(+), 27 deletions(-) diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index e354cc6446ab..9435620062df 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -513,7 +513,7 @@ void __init kvm_guest_init(void) * can get false positives too easily, for example if the host is * overcommitted. */ - watchdog_enable_hardlockup_detector(false); + hardlockup_detector_disable(); } static noinline uint32_t __kvm_cpuid_base(void) diff --git a/include/linux/nmi.h b/include/linux/nmi.h index 0426357297d5..3d46fb4708e0 100644 --- a/include/linux/nmi.h +++ b/include/linux/nmi.h @@ -25,16 +25,11 @@ static inline void touch_nmi_watchdog(void) #endif #if defined(CONFIG_HARDLOCKUP_DETECTOR) -extern void watchdog_enable_hardlockup_detector(bool val); -extern bool watchdog_hardlockup_detector_is_enabled(void); +extern void hardlockup_detector_disable(void); #else -static inline void watchdog_enable_hardlockup_detector(bool val) +static inline void hardlockup_detector_disable(void) { } -static inline bool watchdog_hardlockup_detector_is_enabled(void) -{ - return true; -} #endif /* diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 49d02250aaac..f2be11ab7e08 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -83,8 +83,6 @@ static unsigned long soft_lockup_nmi_warn; #ifdef CONFIG_HARDLOCKUP_DETECTOR static int hardlockup_panic = CONFIG_BOOTPARAM_HARDLOCKUP_PANIC_VALUE; - -static bool hardlockup_detector_enabled = true; /* * We may not want to enable hard lockup detection by default in all cases, * for example when running the kernel as a guest on a hypervisor. In these @@ -93,14 +91,9 @@ static bool hardlockup_detector_enabled = true; * kernel command line parameters are parsed, because otherwise it is not * possible to override this in hardlockup_panic_setup(). */ -void watchdog_enable_hardlockup_detector(bool val) -{ - hardlockup_detector_enabled = val; -} - -bool watchdog_hardlockup_detector_is_enabled(void) +void hardlockup_detector_disable(void) { - return hardlockup_detector_enabled; + watchdog_enabled &= ~NMI_WATCHDOG_ENABLED; } static int __init hardlockup_panic_setup(char *str) @@ -530,15 +523,6 @@ static int watchdog_nmi_enable(unsigned int cpu) if (!(watchdog_enabled & NMI_WATCHDOG_ENABLED)) goto out; - /* - * Some kernels need to default hard lockup detection to - * 'disabled', for example a guest on a hypervisor. - */ - if (!watchdog_hardlockup_detector_is_enabled()) { - event = ERR_PTR(-ENOENT); - goto handle_err; - } - /* is it already setup and enabled? */ if (event && event->state > PERF_EVENT_STATE_OFF) goto out; @@ -553,7 +537,6 @@ static int watchdog_nmi_enable(unsigned int cpu) /* Try to register using hardware perf events */ event = perf_event_create_kernel_counter(wd_attr, cpu, NULL, watchdog_overflow_callback, NULL); -handle_err: /* save cpu0 error for future comparision */ if (cpu == 0 && IS_ERR(event)) cpu0_err = PTR_ERR(event); -- 2.20.1