[PATCH 6/6] powerpc/perf: Add Power8 mem_access event to sysfs

Madhavan Srinivasan
2017-03-05T09:42:10Z

Patch add "mem_access" event to sysfs. This as-is not a raw event
supported by Power8 pmu. Instead, it is formed based on
raw event encoding specificed in isa207-common.h.

Primary PMU event used here is PM_MRK_INST_CMPL.
This event tracks only the completed marked instructions.

Random sampling mode (MMCRA[SM]) with Random Instruction
Sampling (RIS) is enabled to mark type of instructions.

With Random sampling in RLS mode with PM_MRK_INST_CMPL event,
the LDST /DATA_SRC fields in SIER identifies the memory
hierarchy level (eg: L1, L2 etc) statisfied a data-cache
miss for a marked instruction.

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
---
arch/powerpc/perf/power8-events-list.h | 6 ++++++
arch/powerpc/perf/power8-pmu.c | 2 ++
2 files changed, 8 insertions(+)

diff --git a/arch/powerpc/perf/power8-events-list.h b/arch/powerpc/perf/power8-events-list.h
index 3a2e6e8ebb92..0f1d184627cc 100644
--- a/arch/powerpc/perf/power8-events-list.h
+++ b/arch/powerpc/perf/power8-events-list.h
@@ -89,3 +89,9 @@ EVENT(PM_MRK_FILT_MATCH, 0x2013c)
EVENT(PM_MRK_FILT_MATCH_ALT, 0x3012e)
/* Alternate event code for PM_LD_MISS_L1 */
EVENT(PM_LD_MISS_L1_ALT, 0x400f0)
+/*
+ * Memory Access Event -- mem_access
+ * Primary PMU event used here is PM_MRK_INST_CMPL, along with
+ * Random Load/Store Facility Sampling (RIS) in Random sampling mode (MMCRA[SM]).
+ */
+EVENT(MEM_ACCESS, 0x10401e0)
diff --git a/arch/powerpc/perf/power8-pmu.c b/arch/powerpc/perf/power8-pmu.c
index 932d7536f0eb..5463516e369b 100644
--- a/arch/powerpc/perf/power8-pmu.c
+++ b/arch/powerpc/perf/power8-pmu.c
@@ -90,6 +90,7 @@ GENERIC_EVENT_ATTR(branch-instructions, PM_BRU_FIN);
GENERIC_EVENT_ATTR(branch-misses, PM_BR_MPRED_CMPL);
GENERIC_EVENT_ATTR(cache-references, PM_LD_REF_L1);
GENERIC_EVENT_ATTR(cache-misses, PM_LD_MISS_L1);
+GENERIC_EVENT_ATTR(mem_access, MEM_ACCESS);

CACHE_EVENT_ATTR(L1-dcache-load-misses, PM_LD_MISS_L1);
CACHE_EVENT_ATTR(L1-dcache-loads, PM_LD_REF_L1);
@@ -120,6 +121,7 @@ static struct attribute *power8_events_attr[] = {
GENERIC_EVENT_PTR(PM_BR_MPRED_CMPL),
GENERIC_EVENT_PTR(PM_LD_REF_L1),
GENERIC_EVENT_PTR(PM_LD_MISS_L1),
+ GENERIC_EVENT_PTR(MEM_ACCESS),

CACHE_EVENT_PTR(PM_LD_MISS_L1),
CACHE_EVENT_PTR(PM_LD_REF_L1),
--
2.7.4