powerpc/perf: Add Power8 mem_access event to sysfs

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>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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)

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),