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| author | Bitao Hu <yaoma@linux.alibaba.com> | 2024-04-11 15:41:31 +0800 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2024-04-12 17:08:05 +0200 |
| commit | 99cf63c56661be0a0c42f79b56f37a4aa34b4779 (patch) | |
| tree | 10cdfb0ae0ed029482ac5f33efcaad5092fc7ffb /include/linux/kernel_stat.h | |
| parent | 86d2a2f51fbada84e377665df06b5a479a1edc99 (diff) | |
| download | linux-99cf63c56661be0a0c42f79b56f37a4aa34b4779.tar.gz linux-99cf63c56661be0a0c42f79b56f37a4aa34b4779.tar.bz2 linux-99cf63c56661be0a0c42f79b56f37a4aa34b4779.zip | |
genirq: Provide a snapshot mechanism for interrupt statistics
The soft lockup detector lacks a mechanism to identify interrupt storms as
root cause of a lockup. To enable this the detector needs a mechanism to
snapshot the interrupt count statistics on a CPU when the detector observes
a potential lockup scenario and compare that against the interrupt count
when it warns about the lockup later on. The number of interrupts in that
period give a hint whether the lockup might have been caused by an interrupt
storm.
Instead of having extra storage in the lockup detector and accessing the
internals of the interrupt descriptor directly, add a snapshot member to
the per CPU irq_desc::kstat_irq structure and provide interfaces to take a
snapshot of all interrupts on the current CPU and to retrieve the delta of
a specific interrupt later on.
Originally-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Bitao Hu <yaoma@linux.alibaba.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240411074134.30922-3-yaoma@linux.alibaba.com
Diffstat (limited to 'include/linux/kernel_stat.h')
| -rw-r--r-- | include/linux/kernel_stat.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/include/linux/kernel_stat.h b/include/linux/kernel_stat.h index 9935f7ecbfb9..9c042c6384bb 100644 --- a/include/linux/kernel_stat.h +++ b/include/linux/kernel_stat.h @@ -79,6 +79,14 @@ static inline unsigned int kstat_cpu_softirqs_sum(int cpu) return sum; } +#ifdef CONFIG_GENERIC_IRQ_STAT_SNAPSHOT +extern void kstat_snapshot_irqs(void); +extern unsigned int kstat_get_irq_since_snapshot(unsigned int irq); +#else +static inline void kstat_snapshot_irqs(void) { } +static inline unsigned int kstat_get_irq_since_snapshot(unsigned int irq) { return 0; } +#endif + /* * Number of interrupts per specific IRQ source, since bootup */ |