[PATCH v3 4/4] nmi_backtrace: generate one-line reports for idle cpus
From: Rafael J. Wysocki <hidden>
Date: 2016-03-22 22:29:04
Also in:
linux-arch, lkml
On Tuesday, March 22, 2016 01:19:39 PM Chris Metcalf wrote:
When doing an nmi backtrace of many cores, most of which are idle, the output is a little overwhelming and very uninformative. Suppress messages for cpus that are idling when they are interrupted and just emit one line, "NMI backtrace for N skipped: idling at pc 0xNNN". We do this by grouping all the cpuidle code together into a new .cpuidle.text section, and then checking the address of the interrupted PC to see if it lies within that section. This commit suitably tags x86, arm64, and tile idle routines, and only adds in the minimal framework for other architectures. Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Chris Metcalf <redacted> ---
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quoted hunk ↗ jump to hunk
diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c index cd4510a63375..924554f920fb 100644 --- a/drivers/idle/intel_idle.c +++ b/drivers/idle/intel_idle.c@@ -725,8 +725,8 @@ static struct cpuidle_state avn_cstates[] = { * * Must be called under local_irq_disable(). */ -static int intel_idle(struct cpuidle_device *dev, - struct cpuidle_driver *drv, int index) +static __cpuidle int intel_idle(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) { unsigned long ecx = 1; /* break on interrupt flag */ struct cpuidle_state *state = &drv->states[index];
Well, what about intel_idle_freeze()? Or do we not care? And analogous stuff in processor_idle.c for that matter? acpi_idle_enter()/acpi_idle_enter_freeze() plus stuff called by those? Thanks, Rafael