[PATCH] arc: perf: Enable generic "cache-references" and "cache-misses" events

From: Alexey Brodkin
Date: Thu Aug 25 2016 - 07:50:55 EST


We used to live with PERF_COUNT_HW_CACHE_REFERENCES and
PERF_COUNT_HW_CACHE_REFERENCES not specified on ARC.

Those events are actually aliases to 2 cache events that we do support
and so this change sets "cache-reference" and "cache-misses" events
in the same way as "L1-dcache-loads" and L1-dcache-load-misses.

And while at it adding debug info for cache events as well as doing a
subtle fix in HW events debug info - config value is much better
represented by hex so we may see not only event index but as well other
control bits set (if they exist).

Signed-off-by: Alexey Brodkin <abrodkin@xxxxxxxxxxxx>
Cc: Vineet Gupta <vgupta@xxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: linux-snps-arc@xxxxxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
---
arch/arc/include/asm/perf_event.h | 3 +++
arch/arc/kernel/perf_event.c | 6 ++++--
2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/arc/include/asm/perf_event.h b/arch/arc/include/asm/perf_event.h
index 5f07176..9185541 100644
--- a/arch/arc/include/asm/perf_event.h
+++ b/arch/arc/include/asm/perf_event.h
@@ -118,6 +118,9 @@ static const char * const arc_pmu_ev_hw_map[] = {
[PERF_COUNT_ARC_ICM] = "icm", /* I-cache Miss */
[PERF_COUNT_ARC_EDTLB] = "edtlb", /* D-TLB Miss */
[PERF_COUNT_ARC_EITLB] = "eitlb", /* I-TLB Miss */
+
+ [PERF_COUNT_HW_CACHE_REFERENCES] = "imemrdc", /* Instr: mem read cached */
+ [PERF_COUNT_HW_CACHE_MISSES] = "dclm", /* D-cache Load Miss */
};

#define C(_x) PERF_COUNT_HW_CACHE_##_x
diff --git a/arch/arc/kernel/perf_event.c b/arch/arc/kernel/perf_event.c
index 08f03d9..2ce24e7 100644
--- a/arch/arc/kernel/perf_event.c
+++ b/arch/arc/kernel/perf_event.c
@@ -179,8 +179,8 @@ static int arc_pmu_event_init(struct perf_event *event)
if (arc_pmu->ev_hw_idx[event->attr.config] < 0)
return -ENOENT;
hwc->config |= arc_pmu->ev_hw_idx[event->attr.config];
- pr_debug("init event %d with h/w %d \'%s\'\n",
- (int) event->attr.config, (int) hwc->config,
+ pr_debug("init event %d with h/w %08x \'%s\'\n",
+ (int)event->attr.config, (int)hwc->config,
arc_pmu_ev_hw_map[event->attr.config]);
return 0;

@@ -189,6 +189,8 @@ static int arc_pmu_event_init(struct perf_event *event)
if (ret < 0)
return ret;
hwc->config |= arc_pmu->ev_hw_idx[ret];
+ pr_debug("init cache event with h/w %08x \'%s\'\n",
+ (int)hwc->config, arc_pmu_ev_hw_map[ret]);
return 0;
default:
return -ENOENT;
--
2.7.4