This patch adds support for PEBS Precise Store
which is available on Intel Sandy Bridge and
Ivy Bridge processors.
To use Precise store, the proper PEBS event
must be used: mem_trans_retired:precise_stores.
For the perf tool, the generic mem-stores event
exported via sysfs can be used directly.
Signed-off-by: Stephane Eranian <eran...@google.com>
---
arch/x86/kernel/cpu/perf_event.h | 5 +++
arch/x86/kernel/cpu/perf_event_intel.c | 2 ++
arch/x86/kernel/cpu/perf_event_intel_ds.c | 49 +++++++++++++++++++++++++++--
3 files changed, 54 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kernel/cpu/perf_event.h b/arch/x86/kernel/cpu/perf_event.h
index 3f91411..645b864 100644
--- a/arch/x86/kernel/cpu/perf_event.h
+++ b/arch/x86/kernel/cpu/perf_event.h
@@ -66,6 +66,7 @@ struct event_constraint {
* struct event_constraint flags
*/
#define PERF_X86_EVENT_PEBS_LDLAT 0x1 /* ld+ldlat data address sampling */
+#define PERF_X86_EVENT_PEBS_ST 0x2 /* st data address sampling */
struct amd_nb {
int nb_id; /* NorthBridge id */
@@ -242,6 +243,10 @@ struct cpu_hw_events {
__EVENT_CONSTRAINT(c, n, INTEL_ARCH_EVENT_MASK, \
HWEIGHT(n), 0, PERF_X86_EVENT_PEBS_LDLAT)
+#define INTEL_PST_CONSTRAINT(c, n) \
+ __EVENT_CONSTRAINT(c, n, INTEL_ARCH_EVENT_MASK, \
+ HWEIGHT(n), 0, PERF_X86_EVENT_PEBS_ST)
+
#define EVENT_CONSTRAINT_END \
EVENT_CONSTRAINT(0, 0, 0)
diff --git a/arch/x86/kernel/cpu/perf_event_intel.c
b/arch/x86/kernel/cpu/perf_event_intel.c
index 8eced4c..665e26c 100644
--- a/arch/x86/kernel/cpu/perf_event_intel.c
+++ b/arch/x86/kernel/cpu/perf_event_intel.c
@@ -138,6 +138,7 @@ static struct extra_reg intel_snb_extra_regs[]
__read_mostly = {
EVENT_ATTR_STR(mem-loads, mem_ld_nhm, "event=0x0b,umask=0x10,ldlat=3");
EVENT_ATTR_STR(mem-loads, mem_ld_snb, "event=0xcd,umask=0x1,ldlat=3");
+EVENT_ATTR_STR(mem-stores, mem_st_snb, "event=0xcd,umask=0x2");
struct attribute *nhm_events_attrs[] = {
EVENT_PTR(mem_ld_nhm),
@@ -146,6 +147,7 @@ struct attribute *nhm_events_attrs[] = {
struct attribute *snb_events_attrs[] = {
EVENT_PTR(mem_ld_snb),
+ EVENT_PTR(mem_st_snb),
NULL,
};
diff --git a/arch/x86/kernel/cpu/perf_event_intel_ds.c
b/arch/x86/kernel/cpu/perf_event_intel_ds.c
index bdd73bc..cfbd469 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_ds.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_ds.c
@@ -69,6 +69,44 @@ static const u64 pebs_data_source[] = {
OP_LH | P(LVL, UNC) | P(SNOOP, NONE), /* 0x0f: uncached */
};
+static u64 precise_store_data(u64 status)
+{
+ union intel_x86_pebs_dse dse;
+ u64 val = P(OP, STORE) | P(SNOOP, NA) | P(LVL, L1) | P(TLB, L2);
+
+ dse.val = status;
+
+ /*
+ * bit 4: TLB access
+ * 1 = stored missed 2nd level TLB
+ *
+ * so it either hit the walker or the OS
+ * otherwise hit 2nd level TLB
+ */
+ if (dse.st_stlb_miss)
+ val |= P(TLB, MISS);
+ else
+ val |= P(TLB, HIT);
+
+ /*
+ * bit 0: hit L1 data cache
+ * if not set, then all we know is that
+ * it missed L1D
+ */
+ if (dse.st_l1d_hit)
+ val |= P(LVL, HIT);
+ else
+ val |= P(LVL, MISS);
+
+ /*
+ * bit 5: Locked prefix
+ */
+ if (dse.st_locked)
+ val |= P(LOCK, LOCKED);
+
+ return val;
+}
+
static u64 load_latency_data(u64 status)
{
union intel_x86_pebs_dse dse;
@@ -486,6 +524,7 @@ struct event_constraint intel_snb_pebs_event_constraints[]
= {
INTEL_EVENT_CONSTRAINT(0xc4, 0xf), /* BR_INST_RETIRED.* */
INTEL_EVENT_CONSTRAINT(0xc5, 0xf), /* BR_MISP_RETIRED.* */
INTEL_PLD_CONSTRAINT(0x01cd, 0x8), /*
MEM_TRANS_RETIRED.LAT_ABOVE_THR */
+ INTEL_PST_CONSTRAINT(0x02cd, 0x8), /*
MEM_TRANS_RETIRED.PRECISE_STORES */
INTEL_EVENT_CONSTRAINT(0xd0, 0xf), /* MEM_UOP_RETIRED.* */
INTEL_EVENT_CONSTRAINT(0xd1, 0xf), /* MEM_LOAD_UOPS_RETIRED.* */
INTEL_EVENT_CONSTRAINT(0xd2, 0xf), /*
MEM_LOAD_UOPS_LLC_HIT_RETIRED.* */
@@ -500,6 +539,7 @@ struct event_constraint intel_ivb_pebs_event_constraints[]
= {
INTEL_EVENT_CONSTRAINT(0xc4, 0xf), /* BR_INST_RETIRED.* */
INTEL_EVENT_CONSTRAINT(0xc5, 0xf), /* BR_MISP_RETIRED.* */
INTEL_PLD_CONSTRAINT(0x01cd, 0x8), /*
MEM_TRANS_RETIRED.LAT_ABOVE_THR */
+ INTEL_PST_CONSTRAINT(0x02cd, 0x8), /*
MEM_TRANS_RETIRED.PRECISE_STORES */
INTEL_EVENT_CONSTRAINT(0xd0, 0xf), /* MEM_UOP_RETIRED.* */
INTEL_EVENT_CONSTRAINT(0xd1, 0xf), /* MEM_LOAD_UOPS_RETIRED.* */
INTEL_EVENT_CONSTRAINT(0xd2, 0xf), /*
MEM_LOAD_UOPS_LLC_HIT_RETIRED.* */
@@ -537,6 +577,8 @@ void intel_pmu_pebs_enable(struct perf_event *event)
if (event->hw.flags & PERF_X86_EVENT_PEBS_LDLAT)
cpuc->pebs_enabled |= 1ULL << (hwc->idx + 32);
+ else if (event->hw.flags & PERF_X86_EVENT_PEBS_ST)
+ cpuc->pebs_enabled |= 1ULL << 63;
}
void intel_pmu_pebs_disable(struct perf_event *event)
@@ -657,12 +699,13 @@ static void __intel_pmu_pebs_event(struct perf_event
*event,
struct perf_sample_data data;
struct pt_regs regs;
u64 sample_type;
- int fll;
+ int fll, fst;
if (!intel_pmu_save_and_restart(event))
return;
fll = event->hw.flags & PERF_X86_EVENT_PEBS_LDLAT;
+ fst = event->hw.flags & PERF_X86_EVENT_PEBS_ST;
perf_sample_data_init(&data, 0, event->hw.last_period);
@@ -672,7 +715,7 @@ static void __intel_pmu_pebs_event(struct perf_event *event,
/*
* if PEBS-LL or PreciseStore
*/
- if (fll) {
+ if (fll || fst) {
if (sample_type & PERF_SAMPLE_ADDR)
data.addr = pebs->dla;
@@ -688,6 +731,8 @@ static void __intel_pmu_pebs_event(struct perf_event *event,
if (sample_type & PERF_SAMPLE_DSRC) {
if (fll)
data.dsrc.val = load_latency_data(pebs->dse);
+ else
+ data.dsrc.val = precise_store_data(pebs->dse);
}
}
--
1.7.9.5
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