Implementations of NMI watchdogs that use a single piece of hardware to monitor all the CPUs in the system (as opposed to per-CPU implementations such as perf) need to know which CPUs the watchdog is allowed to monitor. In this manner, non-maskable interrupts are directed only to the monitored CPUs.
Cc: "H. Peter Anvin" <[email protected]> Cc: Ashok Raj <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Tony Luck <[email protected]> Cc: "Rafael J. Wysocki" <[email protected]> Cc: Don Zickus <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Frederic Weisbecker <[email protected]> Cc: Alexei Starovoitov <[email protected]> Cc: Babu Moger <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Mathieu Desnoyers <[email protected]> Cc: Masami Hiramatsu <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Philippe Ombredanne <[email protected]> Cc: Colin Ian King <[email protected]> Cc: Byungchul Park <[email protected]> Cc: "Paul E. McKenney" <[email protected]> Cc: "Luis R. Rodriguez" <[email protected]> Cc: Waiman Long <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Randy Dunlap <[email protected]> Cc: Davidlohr Bueso <[email protected]> Cc: Christoffer Dall <[email protected]> Cc: Marc Zyngier <[email protected]> Cc: Kai-Heng Feng <[email protected]> Cc: Konrad Rzeszutek Wilk <[email protected]> Cc: David Rientjes <[email protected]> Cc: "Ravi V. Shankar" <[email protected]> Cc: [email protected] Cc: "David S. Miller" <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: [email protected] Cc: [email protected] Signed-off-by: Ricardo Neri <[email protected]> --- include/linux/nmi.h | 1 + kernel/watchdog.c | 7 ++++++- 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/include/linux/nmi.h b/include/linux/nmi.h index bf5ebcfdd590..b563fb6ef21d 100644 --- a/include/linux/nmi.h +++ b/include/linux/nmi.h @@ -83,6 +83,7 @@ static inline void reset_hung_task_detector(void) { } #if defined(CONFIG_HARDLOCKUP_DETECTOR) extern void hardlockup_detector_disable(void); +extern struct cpumask *watchdog_get_allowed_cpumask(void); extern unsigned int hardlockup_panic; #else static inline void hardlockup_detector_disable(void) {} diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 8fbfda94a67b..367aa81294ef 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -44,7 +44,7 @@ int __read_mostly soft_watchdog_user_enabled = 1; int __read_mostly watchdog_thresh = 10; int __read_mostly nmi_watchdog_available; -struct cpumask watchdog_allowed_mask __read_mostly; +static struct cpumask watchdog_allowed_mask __read_mostly; struct cpumask watchdog_cpumask __read_mostly; unsigned long *watchdog_cpumask_bits = cpumask_bits(&watchdog_cpumask); @@ -92,6 +92,11 @@ static int __init hardlockup_all_cpu_backtrace_setup(char *str) } __setup("hardlockup_all_cpu_backtrace=", hardlockup_all_cpu_backtrace_setup); # endif /* CONFIG_SMP */ + +struct cpumask *watchdog_get_allowed_cpumask(void) +{ + return &watchdog_allowed_mask; +} #endif /* CONFIG_HARDLOCKUP_DETECTOR */ /* -- 2.17.1
