[PATCH v3 4/6] ARCv2: perf: implement exclusion of event counting in user or kernel mode

Alexey Brodkin
2015-08-24T14:20:53Z

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
---

No changes since v2.

No changes since v1.

arch/arc/include/asm/perf_event.h | 3 +++
arch/arc/kernel/perf_event.c | 16 ++++++++++++++--
2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/arch/arc/include/asm/perf_event.h b/arch/arc/include/asm/perf_event.h
index 9ed593e..876e216 100644
--- a/arch/arc/include/asm/perf_event.h
+++ b/arch/arc/include/asm/perf_event.h
@@ -34,6 +34,9 @@
#define ARC_REG_PCT_INT_CTRL 0x25E
#define ARC_REG_PCT_INT_ACT 0x25F

+#define ARC_REG_PCT_CONFIG_USER (1 << 18) /* count in user mode */
+#define ARC_REG_PCT_CONFIG_KERN (1 << 19) /* count in kernel mode */
+
#define ARC_REG_PCT_CONTROL_CC (1 << 16) /* clear counts */
#define ARC_REG_PCT_CONTROL_SN (1 << 17) /* snapshot */

diff --git a/arch/arc/kernel/perf_event.c b/arch/arc/kernel/perf_event.c
index ce0fa60..997ccbd 100644
--- a/arch/arc/kernel/perf_event.c
+++ b/arch/arc/kernel/perf_event.c
@@ -147,13 +147,25 @@ static int arc_pmu_event_init(struct perf_event *event)
local64_set(&hwc->period_left, hwc->sample_period);
}

+ hwc->config = 0;
+
+ if (is_isa_arcv2()) {
+ /* "exclude user" means "count only kernel" */
+ if (event->attr.exclude_user)
+ hwc->config |= ARC_REG_PCT_CONFIG_KERN;
+
+ /* "exclude kernel" means "count only user" */
+ if (event->attr.exclude_kernel)
+ hwc->config |= ARC_REG_PCT_CONFIG_USER;
+ }
+
switch (event->attr.type) {
case PERF_TYPE_HARDWARE:
if (event->attr.config >= PERF_COUNT_HW_MAX)
return -ENOENT;
if (arc_pmu->ev_hw_idx[event->attr.config] < 0)
return -ENOENT;
- hwc->config = arc_pmu->ev_hw_idx[event->attr.config];
+ 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,
arc_pmu_ev_hw_map[event->attr.config]);
@@ -163,7 +175,7 @@ static int arc_pmu_event_init(struct perf_event *event)
ret = arc_pmu_cache_event(event->attr.config);
if (ret < 0)
return ret;
- hwc->config = arc_pmu->ev_hw_idx[ret];
+ hwc->config |= arc_pmu->ev_hw_idx[ret];
return 0;
default:
return -ENOENT;
--
2.4.3