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| author | Nicholas Piggin <npiggin@gmail.com> | 2018-05-05 09:26:00 +0200 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2018-05-10 15:25:11 +0200 |
| commit | 4e49226ea8e1810d2c14d9e92a290bad239b512b (patch) | |
| tree | 1c54354ad0c32e72d10ae829399407d709235808 /arch/powerpc/kernel | |
| parent | powerpc/watchdog: don't update the watchdog timestamp if a lockup is detected (diff) | |
| download | linux-4e49226ea8e1810d2c14d9e92a290bad239b512b.tar.xz linux-4e49226ea8e1810d2c14d9e92a290bad239b512b.zip | |
powerpc/watchdog: provide more data in watchdog messages
Provide timebase and timebase of last heartbeat in watchdog lockup
messages. Also provide a stack trace of when a CPU becomes un-stuck,
which can be useful -- it could be where irqs are re-enabled, so it
may be the end of the critical section which is responsible for the
latency which is useful information.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/kernel')
| -rw-r--r-- | arch/powerpc/kernel/watchdog.c | 28 |
1 files changed, 25 insertions, 3 deletions
diff --git a/arch/powerpc/kernel/watchdog.c b/arch/powerpc/kernel/watchdog.c index b2d3bdff03aa..1d82274f7e9f 100644 --- a/arch/powerpc/kernel/watchdog.c +++ b/arch/powerpc/kernel/watchdog.c @@ -111,7 +111,13 @@ static inline void wd_smp_unlock(unsigned long *flags) static void wd_lockup_ipi(struct pt_regs *regs) { - pr_emerg("CPU %d Hard LOCKUP\n", raw_smp_processor_id()); + int cpu = raw_smp_processor_id(); + u64 tb = get_tb(); + + pr_emerg("CPU %d Hard LOCKUP\n", cpu); + pr_emerg("CPU %d TB:%lld, last heartbeat TB:%lld (%lldms ago)\n", + cpu, tb, per_cpu(wd_timer_tb, cpu), + tb_to_ns(tb - per_cpu(wd_timer_tb, cpu)) / 1000000); print_modules(); print_irqtrace_events(current); if (regs) @@ -154,6 +160,9 @@ static void watchdog_smp_panic(int cpu, u64 tb) pr_emerg("CPU %d detected hard LOCKUP on other CPUs %*pbl\n", cpu, cpumask_pr_args(&wd_smp_cpus_pending)); + pr_emerg("CPU %d TB:%lld, last SMP heartbeat TB:%lld (%lldms ago)\n", + cpu, tb, wd_smp_last_reset_tb, + tb_to_ns(tb - wd_smp_last_reset_tb) / 1000000); if (!sysctl_hardlockup_all_cpu_backtrace) { /* @@ -194,10 +203,19 @@ static void wd_smp_clear_cpu_pending(int cpu, u64 tb) { if (!cpumask_test_cpu(cpu, &wd_smp_cpus_pending)) { if (unlikely(cpumask_test_cpu(cpu, &wd_smp_cpus_stuck))) { + struct pt_regs *regs = get_irq_regs(); unsigned long flags; - pr_emerg("CPU %d became unstuck\n", cpu); wd_smp_lock(&flags); + + pr_emerg("CPU %d became unstuck TB:%lld\n", + cpu, tb); + print_irqtrace_events(current); + if (regs) + show_regs(regs); + else + dump_stack(); + cpumask_clear_cpu(cpu, &wd_smp_cpus_stuck); wd_smp_unlock(&flags); } @@ -252,7 +270,11 @@ void soft_nmi_interrupt(struct pt_regs *regs) } set_cpu_stuck(cpu, tb); - pr_emerg("CPU %d self-detected hard LOCKUP @ %pS\n", cpu, (void *)regs->nip); + pr_emerg("CPU %d self-detected hard LOCKUP @ %pS\n", + cpu, (void *)regs->nip); + pr_emerg("CPU %d TB:%lld, last heartbeat TB:%lld (%lldms ago)\n", + cpu, tb, per_cpu(wd_timer_tb, cpu), + tb_to_ns(tb - per_cpu(wd_timer_tb, cpu)) / 1000000); print_modules(); print_irqtrace_events(current); show_regs(regs); |