[PATCH] Powerpc/perf: Wire up PMI throttling

From: Ravi Bangoria
Date: Wed Nov 14 2018 - 09:14:27 EST


Commit 14c63f17b1fde ("perf: Drop sample rate when sampling is too
slow") introduced a way to throttle PMU interrupts if we're spending
too much time just processing those. Wire up powerpc PMI handler to
use this infrastructure.

Signed-off-by: Ravi Bangoria <ravi.bangoria@xxxxxxxxxxxxx>
---
arch/powerpc/kernel/traps.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 9a86572db1ef..44f85fa22356 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -18,6 +18,7 @@
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/sched/debug.h>
+#include <linux/sched/clock.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/pkeys.h>
@@ -1803,9 +1804,12 @@ void vsx_unavailable_tm(struct pt_regs *regs)

void performance_monitor_exception(struct pt_regs *regs)
{
+ u64 start_clock;
__this_cpu_inc(irq_stat.pmu_irqs);

+ start_clock = sched_clock();
perf_irq(regs);
+ perf_sample_event_took(sched_clock() - start_clock);
}

#ifdef CONFIG_PPC_ADV_DEBUG_REGS
--
2.19.1