diff options
Diffstat (limited to 'arch/powerpc/kernel/time.c')
| -rw-r--r-- | arch/powerpc/kernel/time.c | 19 |
1 files changed, 13 insertions, 6 deletions
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index ad876906f847..5862a3611795 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -578,22 +578,29 @@ void timer_interrupt(struct pt_regs *regs) struct pt_regs *old_regs; u64 now; - /* Ensure a positive value is written to the decrementer, or else - * some CPUs will continue to take decrementer exceptions. - */ - set_dec(decrementer_max); - /* Some implementations of hotplug will get timer interrupts while * offline, just ignore these and we also need to set * decrementers_next_tb as MAX to make sure __check_irq_replay * don't replay timer interrupt when return, otherwise we'll trap * here infinitely :( */ - if (!cpu_online(smp_processor_id())) { + if (unlikely(!cpu_online(smp_processor_id()))) { *next_tb = ~(u64)0; + set_dec(decrementer_max); return; } + /* Ensure a positive value is written to the decrementer, or else + * some CPUs will continue to take decrementer exceptions. When the + * PPC_WATCHDOG (decrementer based) is configured, keep this at most + * 31 bits, which is about 4 seconds on most systems, which gives + * the watchdog a chance of catching timer interrupt hard lockups. + */ + if (IS_ENABLED(CONFIG_PPC_WATCHDOG)) + set_dec(0x7fffffff); + else + set_dec(decrementer_max); + /* Conditionally hard-enable interrupts now that the DEC has been * bumped to its maximum value */ |