diff options
| author | Zhen Lei <thunder.leizhen@huawei.com> | 2022-11-19 17:25:05 +0800 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@kernel.org> | 2023-01-05 12:21:11 -0800 |
| commit | 7c182722a0a9447e31f9645de4f311e5bc59b480 (patch) | |
| tree | c394fb7c54824a6bf0eb8c7c45115a73d17ad675 | |
| parent | 3ca0a6ea8f6de0f21a9331ff3596a9c073fbdab0 (diff) | |
sched: Add helper nr_context_switches_cpu()
Add a function nr_context_switches_cpu() that returns number of context
switches since boot on the specified CPU. This information will be used
to diagnose RCU CPU stalls.
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Daniel Bristot de Oliveira <bristot@redhat.com>
Cc: Valentin Schneider <vschneid@redhat.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
| -rw-r--r-- | include/linux/kernel_stat.h | 1 | ||||
| -rw-r--r-- | kernel/sched/core.c | 5 |
2 files changed, 6 insertions, 0 deletions
diff --git a/include/linux/kernel_stat.h b/include/linux/kernel_stat.h index 898076e173a9..9935f7ecbfb9 100644 --- a/include/linux/kernel_stat.h +++ b/include/linux/kernel_stat.h @@ -52,6 +52,7 @@ DECLARE_PER_CPU(struct kernel_cpustat, kernel_cpustat); #define kstat_cpu(cpu) per_cpu(kstat, cpu) #define kcpustat_cpu(cpu) per_cpu(kernel_cpustat, cpu) +extern unsigned long long nr_context_switches_cpu(int cpu); extern unsigned long long nr_context_switches(void); extern unsigned int kstat_irqs_cpu(unsigned int irq, int cpu); diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 25b582b6ee5f..2e40a6c116e1 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -5282,6 +5282,11 @@ bool single_task_running(void) } EXPORT_SYMBOL(single_task_running); +unsigned long long nr_context_switches_cpu(int cpu) +{ + return cpu_rq(cpu)->nr_switches; +} + unsigned long long nr_context_switches(void) { int i; |