| Message ID | 1475792203-230942-2-git-send-email-babu.moger@oracle.com |
|---|---|
| State | Superseded |
| Delegated to: | David Miller |
| Headers | show |
On Thu, Oct 06, 2016 at 03:16:42PM -0700, Babu Moger wrote: > Currently we do not have a way to enable/disable arch specific > watchdog handlers if it was implemented by any of the architectures. > > This patch introduces new function update_arch_nmi_watchdog > which can be used to enable/disable architecture specific NMI > watchdog handlers. Also exposes watchdog_enabled variable outside > so that arch specific nmi watchdogs can use it to implement > enalbe/disable behavour. > > Signed-off-by: Babu Moger <babu.moger@oracle.com> > --- > include/linux/nmi.h | 1 + > kernel/watchdog.c | 16 +++++++++++++--- > 2 files changed, 14 insertions(+), 3 deletions(-) > > diff --git a/include/linux/nmi.h b/include/linux/nmi.h > index 4630eea..01b4830 100644 > --- a/include/linux/nmi.h > +++ b/include/linux/nmi.h > @@ -66,6 +66,7 @@ static inline bool trigger_allbutself_cpu_backtrace(void) > > #ifdef CONFIG_LOCKUP_DETECTOR > u64 hw_nmi_get_sample_period(int watchdog_thresh); > +extern unsigned long watchdog_enabled; The extern is within an #ifdef, but the definition later is valid alway. So extern definition should be outside the #ifdef to match the actual implementation. To manipulate / read watchdog_enabled two constants are used: NMI_WATCHDOG_ENABLED, SOFT_WATCHDOG_ENABLED They should be visible too, so uses do not fall into the trap and uses constants (like in patch 2). Sam -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 10/6/2016 11:34 PM, Sam Ravnborg wrote: > On Thu, Oct 06, 2016 at 03:16:42PM -0700, Babu Moger wrote: >> Currently we do not have a way to enable/disable arch specific >> watchdog handlers if it was implemented by any of the architectures. >> >> This patch introduces new function update_arch_nmi_watchdog >> which can be used to enable/disable architecture specific NMI >> watchdog handlers. Also exposes watchdog_enabled variable outside >> so that arch specific nmi watchdogs can use it to implement >> enalbe/disable behavour. >> >> Signed-off-by: Babu Moger <babu.moger@oracle.com> >> --- >> include/linux/nmi.h | 1 + >> kernel/watchdog.c | 16 +++++++++++++--- >> 2 files changed, 14 insertions(+), 3 deletions(-) >> >> diff --git a/include/linux/nmi.h b/include/linux/nmi.h >> index 4630eea..01b4830 100644 >> --- a/include/linux/nmi.h >> +++ b/include/linux/nmi.h >> @@ -66,6 +66,7 @@ static inline bool trigger_allbutself_cpu_backtrace(void) >> >> #ifdef CONFIG_LOCKUP_DETECTOR >> u64 hw_nmi_get_sample_period(int watchdog_thresh); >> +extern unsigned long watchdog_enabled; > The extern is within an #ifdef, but the definition later is > valid alway. > So extern definition should be outside the #ifdef to match the > actual implementation. Ok. Sure. > > To manipulate / read watchdog_enabled two constants are used: > NMI_WATCHDOG_ENABLED, SOFT_WATCHDOG_ENABLED Sure. I will bring these definitions to nmi.h from watchdog.c > They should be visible too, so uses do not fall into the trap > and uses constants (like in patch 2). Will re-post v2 version with these changes. Thanks for the comments. > > Sam -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/include/linux/nmi.h b/include/linux/nmi.h index 4630eea..01b4830 100644 --- a/include/linux/nmi.h +++ b/include/linux/nmi.h @@ -66,6 +66,7 @@ static inline bool trigger_allbutself_cpu_backtrace(void) #ifdef CONFIG_LOCKUP_DETECTOR u64 hw_nmi_get_sample_period(int watchdog_thresh); +extern unsigned long watchdog_enabled; extern int nmi_watchdog_enabled; extern int soft_watchdog_enabled; extern int watchdog_user_enabled; diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 9acb29f..1ac2814 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -46,16 +46,21 @@ static DEFINE_MUTEX(watchdog_proc_mutex); -#ifdef CONFIG_HARDLOCKUP_DETECTOR -static unsigned long __read_mostly watchdog_enabled = SOFT_WATCHDOG_ENABLED|NMI_WATCHDOG_ENABLED; +#if defined(CONFIG_HARDLOCKUP_DETECTOR) || defined(CONFIG_HAVE_NMI_WATCHDOG) +unsigned long __read_mostly watchdog_enabled = SOFT_WATCHDOG_ENABLED|NMI_WATCHDOG_ENABLED; #else -static unsigned long __read_mostly watchdog_enabled = SOFT_WATCHDOG_ENABLED; +unsigned long __read_mostly watchdog_enabled = SOFT_WATCHDOG_ENABLED; #endif int __read_mostly nmi_watchdog_enabled; int __read_mostly soft_watchdog_enabled; int __read_mostly watchdog_user_enabled; int __read_mostly watchdog_thresh = 10; +/* + * Implemented by arch specific handlers if it defines CONFIG_HAVE_NMI_WATCHDOG + */ +void __weak update_arch_nmi_watchdog(void) {} + #ifdef CONFIG_SMP int __read_mostly sysctl_softlockup_all_cpu_backtrace; int __read_mostly sysctl_hardlockup_all_cpu_backtrace; @@ -842,6 +847,11 @@ static int proc_watchdog_update(void) int err = 0; /* + * Enable/Disable arch specific nmi watchdogs if there is one + */ + update_arch_nmi_watchdog(); + + /* * Watchdog threads won't be started if they are already active. * The 'watchdog_running' variable in watchdog_*_all_cpus() takes * care of this. If those threads are already active, the sample
Currently we do not have a way to enable/disable arch specific watchdog handlers if it was implemented by any of the architectures. This patch introduces new function update_arch_nmi_watchdog which can be used to enable/disable architecture specific NMI watchdog handlers. Also exposes watchdog_enabled variable outside so that arch specific nmi watchdogs can use it to implement enalbe/disable behavour. Signed-off-by: Babu Moger <babu.moger@oracle.com> --- include/linux/nmi.h | 1 + kernel/watchdog.c | 16 +++++++++++++--- 2 files changed, 14 insertions(+), 3 deletions(-)