[RFC 05/11] perf tools: Enable record and script to record and show hazard data

[Ravi Bangoria]

From: Madhavan Srinivasan <maddy at linux.vnet.ibm.com>

Introduce new perf record option "--hazard" to capture cpu pipeline
hazard data. Also enable perf script -D to dump raw values of it.
Sample o/p:

  $ ./perf record -e r4010e --hazard -- ls
  $ ./perf script -D
  ... PERF_RECORD_SAMPLE(IP, 0x2): ...
  hazard information:
  Inst Type 0x1
  Inst Cache 0x1
  Hazard Stage 0x4
  Hazard Reason 0x3
  Stall Stage 0x4
  Stall Reason 0x2

Signed-off-by: Madhavan Srinivasan <maddy at linux.vnet.ibm.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria at linux.ibm.com>
---
 tools/perf/Documentation/perf-record.txt  |  3 +++
 tools/perf/builtin-record.c               |  1 +
 tools/perf/util/event.h                   |  1 +
 tools/perf/util/evsel.c                   | 10 ++++++++++
 tools/perf/util/perf_event_attr_fprintf.c |  1 +
 tools/perf/util/record.h                  |  1 +
 tools/perf/util/session.c                 | 16 ++++++++++++++++
 7 files changed, 33 insertions(+)

diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt
index b23a4012a606..e7bd1b6938ce 100644
--- a/tools/perf/Documentation/perf-record.txt
+++ b/tools/perf/Documentation/perf-record.txt
@@ -283,6 +283,9 @@ OPTIONS
 --phys-data::
 	Record the sample physical addresses.
 
+--hazard::
+	Record processor pipeline hazard and stall information.
+
 -T::
 --timestamp::
 	Record the sample timestamps. Use it with 'perf report -D' to see the
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 4c301466101b..6bd32d7bc4e9 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -2301,6 +2301,7 @@ static struct option __record_options[] = {
 	OPT_BOOLEAN('s', "stat", &record.opts.inherit_stat,
 		    "per thread counts"),
 	OPT_BOOLEAN('d', "data", &record.opts.sample_address, "Record the sample addresses"),
+	OPT_BOOLEAN(0, "hazard", &record.opts.hazard, "Record processor pipeline hazard and stall information"),
 	OPT_BOOLEAN(0, "phys-data", &record.opts.sample_phys_addr,
 		    "Record the sample physical addresses"),
 	OPT_BOOLEAN(0, "sample-cpu", &record.opts.sample_cpu, "Record the sample cpu"),
diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h
index 85223159737c..ff0f03253a95 100644
--- a/tools/perf/util/event.h
+++ b/tools/perf/util/event.h
@@ -148,6 +148,7 @@ struct perf_sample {
 	struct stack_dump user_stack;
 	struct sample_read read;
 	struct aux_sample aux_sample;
+	struct perf_pipeline_haz_data *pipeline_haz;
 };
 
 #define PERF_MEM_DATA_SRC_NONE \
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index c8dc4450884c..e37ed7929c2c 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1080,6 +1080,9 @@ void perf_evsel__config(struct evsel *evsel, struct record_opts *opts,
 	if (opts->sample_phys_addr)
 		perf_evsel__set_sample_bit(evsel, PHYS_ADDR);
 
+	if (opts->hazard)
+		perf_evsel__set_sample_bit(evsel, PIPELINE_HAZ);
+
 	if (opts->no_buffering) {
 		attr->watermark = 0;
 		attr->wakeup_events = 1;
@@ -2265,6 +2268,13 @@ int perf_evsel__parse_sample(struct evsel *evsel, union perf_event *event,
 		array = (void *)array + sz;
 	}
 
+	if (type & PERF_SAMPLE_PIPELINE_HAZ) {
+		sz = sizeof(struct perf_pipeline_haz_data);
+		OVERFLOW_CHECK(array, sz, max_size);
+		data->pipeline_haz = (struct perf_pipeline_haz_data *)array;
+		array = (void *)array + sz;
+	}
+
 	return 0;
 }
 
diff --git a/tools/perf/util/perf_event_attr_fprintf.c b/tools/perf/util/perf_event_attr_fprintf.c
index 651203126c71..d97e755c886b 100644
--- a/tools/perf/util/perf_event_attr_fprintf.c
+++ b/tools/perf/util/perf_event_attr_fprintf.c
@@ -35,6 +35,7 @@ static void __p_sample_type(char *buf, size_t size, u64 value)
 		bit_name(BRANCH_STACK), bit_name(REGS_USER), bit_name(STACK_USER),
 		bit_name(IDENTIFIER), bit_name(REGS_INTR), bit_name(DATA_SRC),
 		bit_name(WEIGHT), bit_name(PHYS_ADDR), bit_name(AUX),
+		bit_name(PIPELINE_HAZ),
 		{ .name = NULL, }
 	};
 #undef bit_name
diff --git a/tools/perf/util/record.h b/tools/perf/util/record.h
index 5421fd2ad383..f1678a0bc8ce 100644
--- a/tools/perf/util/record.h
+++ b/tools/perf/util/record.h
@@ -67,6 +67,7 @@ struct record_opts {
 	int	      affinity;
 	int	      mmap_flush;
 	unsigned int  comp_level;
+	bool	      hazard;
 };
 
 extern const char * const *record_usage;
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index d0d7d25b23e3..834ca7df2349 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -1153,6 +1153,19 @@ static void stack_user__printf(struct stack_dump *dump)
 	       dump->size, dump->offset);
 }
 
+static void pipeline_hazard__printf(struct perf_sample *sample)
+{
+	struct perf_pipeline_haz_data *haz = sample->pipeline_haz;
+
+	printf("... hazard information:\n");
+	printf(".... Inst Type 0x%" PRIx32 "\n", haz->itype);
+	printf(".... Inst Cache 0x%" PRIx32 "\n", haz->icache);
+	printf(".... Hazard Stage 0x%" PRIx32 "\n", haz->hazard_stage);
+	printf(".... Hazard Reason 0x%" PRIx32 "\n", haz->hazard_reason);
+	printf(".... Stall Stage 0x%" PRIx32 "\n", haz->stall_stage);
+	printf(".... Stall Reason 0x%" PRIx32 "\n", haz->stall_reason);
+}
+
 static void perf_evlist__print_tstamp(struct evlist *evlist,
 				       union perf_event *event,
 				       struct perf_sample *sample)
@@ -1251,6 +1264,9 @@ static void dump_sample(struct evsel *evsel, union perf_event *event,
 	if (sample_type & PERF_SAMPLE_STACK_USER)
 		stack_user__printf(&sample->user_stack);
 
+	if (sample_type & PERF_SAMPLE_PIPELINE_HAZ)
+		pipeline_hazard__printf(sample);
+
 	if (sample_type & PERF_SAMPLE_WEIGHT)
 		printf("... weight: %" PRIu64 "\n", sample->weight);
 
-- 
2.21.1