[PATCH 3.18 07/90] sparc: Throttle perf events properly.

From: Greg Kroah-Hartman
Date: Mon Nov 19 2018 - 12:04:09 EST


3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: "David S. Miller" <davem@xxxxxxxxxxxxx>

[ Upstream commit 455adb3174d2c8518cef1a61140c211f6ac224d2 ]

Like x86 and arm, call perf_sample_event_took() in perf event
NMI interrupt handler.

Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/sparc/kernel/perf_event.c | 9 +++++++++
1 file changed, 9 insertions(+)

--- a/arch/sparc/kernel/perf_event.c
+++ b/arch/sparc/kernel/perf_event.c
@@ -23,6 +23,7 @@
#include <asm/cpudata.h>
#include <asm/uaccess.h>
#include <linux/atomic.h>
+#include <linux/sched/clock.h>
#include <asm/nmi.h>
#include <asm/pcr.h>
#include <asm/cacheflush.h>
@@ -1586,6 +1587,8 @@ static int __kprobes perf_event_nmi_hand
struct perf_sample_data data;
struct cpu_hw_events *cpuc;
struct pt_regs *regs;
+ u64 finish_clock;
+ u64 start_clock;
int i;

if (!atomic_read(&active_events))
@@ -1599,6 +1602,8 @@ static int __kprobes perf_event_nmi_hand
return NOTIFY_DONE;
}

+ start_clock = sched_clock();
+
regs = args->regs;

cpuc = this_cpu_ptr(&cpu_hw_events);
@@ -1637,6 +1642,10 @@ static int __kprobes perf_event_nmi_hand
sparc_pmu_stop(event, 0);
}

+ finish_clock = sched_clock();
+
+ perf_sample_event_took(finish_clock - start_clock);
+
return NOTIFY_STOP;
}