diff mbox series

[v1,4/4] tools/perf: Modify event parser to support alt-period-jitter term

Message ID 20241107160721.1401614-5-deepak.surti@arm.com (mailing list archive)
State New
Headers show
Series A mechanism for efficient support for per-function metrics | expand

Commit Message

Deepak Surti Nov. 7, 2024, 4:07 p.m. UTC 
From: Ben Gainey <ben.gainey@arm.com>

parse-events is modified, adding the "alt-period-jitter" term which
can be used to enable random jitter of the alternative sample
period.

Signed-off-by: Ben Gainey <ben.gainey@arm.com>
---
 tools/include/uapi/linux/perf_event.h             | 10 +++++++++-
 tools/perf/tests/attr.c                           |  1 +
 tools/perf/tests/attr.py                          |  1 +
 tools/perf/tests/attr/base-record                 |  3 ++-
 tools/perf/tests/attr/base-record-spe             |  3 ++-
 tools/perf/tests/attr/base-stat                   |  1 +
 tools/perf/tests/attr/system-wide-dummy           |  1 +
 .../tests/attr/test-record-alt-period-jitter-term | 13 +++++++++++++
 tools/perf/tests/attr/test-record-dummy-C0        |  1 +
 tools/perf/util/parse-events.c                    | 15 +++++++++++++++
 tools/perf/util/parse-events.h                    |  3 ++-
 tools/perf/util/parse-events.l                    |  1 +
 tools/perf/util/pmu.c                             |  1 +
 13 files changed, 50 insertions(+), 4 deletions(-)
 create mode 100644 tools/perf/tests/attr/test-record-alt-period-jitter-term
diff mbox series

Patch

diff --git a/tools/include/uapi/linux/perf_event.h b/tools/include/uapi/linux/perf_event.h
index bedae424ba36..16dbeea5803e 100644
--- a/tools/include/uapi/linux/perf_event.h
+++ b/tools/include/uapi/linux/perf_event.h
@@ -461,7 +461,15 @@  struct perf_event_attr {
 				inherit_thread :  1, /* children only inherit if cloned with CLONE_THREAD */
 				remove_on_exec :  1, /* event is removed from task on exec */
 				sigtrap        :  1, /* send synchronous SIGTRAP on event */
-				__reserved_1   : 26;
+				/*
+				 * jitter_alternate_period:
+				 *
+				 * add a limited amount of jitter on each
+				 * alternate period, where the jitter is between
+				 * [0, (2<<jitter_alternate_period) - 1]
+				 */
+				jitter_alternate_period : 3,
+				__reserved_1   : 23;
 
 	union {
 		__u32		wakeup_events;	  /* wakeup every n events */
diff --git a/tools/perf/tests/attr.c b/tools/perf/tests/attr.c
index 956b58c7ba8f..7fb5d1d0b0ab 100644
--- a/tools/perf/tests/attr.c
+++ b/tools/perf/tests/attr.c
@@ -140,6 +140,7 @@  static int store_event(struct perf_event_attr *attr, pid_t pid, struct perf_cpu
 	WRITE_ASS(sample_regs_user,   "llu");
 	WRITE_ASS(sample_stack_user,  PRIu32);
 	WRITE_ASS(alternative_sample_period,  "llu");
+	WRITE_ASS(jitter_alternate_period,  "d");
 
 	fclose(file);
 	return 0;
diff --git a/tools/perf/tests/attr.py b/tools/perf/tests/attr.py
index 75c4527393f9..ecab8e69418f 100644
--- a/tools/perf/tests/attr.py
+++ b/tools/perf/tests/attr.py
@@ -92,6 +92,7 @@  class Event(dict):
         'sample_regs_user',
         'sample_stack_user',
         'alternative_sample_period',
+        'jitter_alternate_period',
     ]
 
     def add(self, data):
diff --git a/tools/perf/tests/attr/base-record b/tools/perf/tests/attr/base-record
index 403de2e2c891..39a7228612c2 100644
--- a/tools/perf/tests/attr/base-record
+++ b/tools/perf/tests/attr/base-record
@@ -39,4 +39,5 @@  config2=0
 branch_sample_type=0
 sample_regs_user=0
 sample_stack_user=0
-alternative_sample_period=0
\ No newline at end of file
+alternative_sample_period=0
+jitter_alternate_period=0
diff --git a/tools/perf/tests/attr/base-record-spe b/tools/perf/tests/attr/base-record-spe
index db528d7d8b73..b228cd98cfa1 100644
--- a/tools/perf/tests/attr/base-record-spe
+++ b/tools/perf/tests/attr/base-record-spe
@@ -38,4 +38,5 @@  config2=*
 branch_sample_type=*
 sample_regs_user=*
 sample_stack_user=*
-alternative_sample_period=0
\ No newline at end of file
+alternative_sample_period=0
+jitter_alternate_period=0
diff --git a/tools/perf/tests/attr/base-stat b/tools/perf/tests/attr/base-stat
index 27ef0fa1386f..d9057d780262 100644
--- a/tools/perf/tests/attr/base-stat
+++ b/tools/perf/tests/attr/base-stat
@@ -40,3 +40,4 @@  branch_sample_type=0
 sample_regs_user=0
 sample_stack_user=0
 alternative_sample_period=0
+jitter_alternate_period=0
diff --git a/tools/perf/tests/attr/system-wide-dummy b/tools/perf/tests/attr/system-wide-dummy
index 5c4d2a60931d..4d80542c3a68 100644
--- a/tools/perf/tests/attr/system-wide-dummy
+++ b/tools/perf/tests/attr/system-wide-dummy
@@ -51,3 +51,4 @@  branch_sample_type=0
 sample_regs_user=0
 sample_stack_user=0
 alternative_sample_period=0
+jitter_alternate_period=0
diff --git a/tools/perf/tests/attr/test-record-alt-period-jitter-term b/tools/perf/tests/attr/test-record-alt-period-jitter-term
new file mode 100644
index 000000000000..cda28c1ec8dd
--- /dev/null
+++ b/tools/perf/tests/attr/test-record-alt-period-jitter-term
@@ -0,0 +1,13 @@ 
+[config]
+command = record
+args    = --no-bpf-event -e cycles/period=3,alt-period=2,alt-period-jitter=7/ -- kill >/dev/null 2>&1
+ret     = 1
+kernel_since = 6.11
+
+[event-10:base-record]
+sample_period=3
+alternative_sample_period=2
+jitter_alternate_period=7
+
+freq=0
+sample_type=7
diff --git a/tools/perf/tests/attr/test-record-dummy-C0 b/tools/perf/tests/attr/test-record-dummy-C0
index d4f0546e02b6..0f3360c35a5e 100644
--- a/tools/perf/tests/attr/test-record-dummy-C0
+++ b/tools/perf/tests/attr/test-record-dummy-C0
@@ -54,3 +54,4 @@  branch_sample_type=0
 sample_regs_user=0
 sample_stack_user=0
 alternative_sample_period=0
+jitter_alternate_period=0
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 48723cea3a51..d3a4f52a7644 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -827,6 +827,7 @@  static const char *config_term_name(enum parse_events__term_type term_type)
 		[PARSE_EVENTS__TERM_TYPE_LEGACY_CACHE]          = "legacy-cache",
 		[PARSE_EVENTS__TERM_TYPE_HARDWARE]              = "hardware",
 		[PARSE_EVENTS__TERM_TYPE_ALT_SAMPLE_PERIOD]	= "alt-period",
+		[PARSE_EVENTS__TERM_TYPE_ALT_PERIOD_JITTER]	= "alt-period-jitter",
 	};
 	if ((unsigned int)term_type >= __PARSE_EVENTS__TERM_TYPE_NR)
 		return "unknown term";
@@ -856,6 +857,7 @@  config_term_avail(enum parse_events__term_type term_type, struct parse_events_er
 	case PARSE_EVENTS__TERM_TYPE_METRIC_ID:
 	case PARSE_EVENTS__TERM_TYPE_SAMPLE_PERIOD:
 	case PARSE_EVENTS__TERM_TYPE_ALT_SAMPLE_PERIOD:
+	case PARSE_EVENTS__TERM_TYPE_ALT_PERIOD_JITTER:
 	case PARSE_EVENTS__TERM_TYPE_PERCORE:
 		return true;
 	case PARSE_EVENTS__TERM_TYPE_USER:
@@ -1010,6 +1012,16 @@  do {									   \
 		}
 		attr->alternative_sample_period = term->val.num;
 		break;
+	case PARSE_EVENTS__TERM_TYPE_ALT_PERIOD_JITTER:
+		CHECK_TYPE_VAL(NUM);
+		if ((unsigned int)term->val.num > 7) {
+			parse_events_error__handle(err, term->err_val,
+						strdup("expected a value between 0-7"),
+						NULL);
+			return -EINVAL;
+		}
+		attr->jitter_alternate_period = (unsigned int)term->val.num;
+		break;
 	case PARSE_EVENTS__TERM_TYPE_DRV_CFG:
 	case PARSE_EVENTS__TERM_TYPE_USER:
 	case PARSE_EVENTS__TERM_TYPE_LEGACY_CACHE:
@@ -1137,6 +1149,7 @@  static int config_term_tracepoint(struct perf_event_attr *attr,
 	case PARSE_EVENTS__TERM_TYPE_LEGACY_CACHE:
 	case PARSE_EVENTS__TERM_TYPE_HARDWARE:
 	case PARSE_EVENTS__TERM_TYPE_ALT_SAMPLE_PERIOD:
+	case PARSE_EVENTS__TERM_TYPE_ALT_PERIOD_JITTER:
 	default:
 		if (err) {
 			parse_events_error__handle(err, term->err_term,
@@ -1269,6 +1282,7 @@  do {								\
 		case PARSE_EVENTS__TERM_TYPE_LEGACY_CACHE:
 		case PARSE_EVENTS__TERM_TYPE_HARDWARE:
 		case PARSE_EVENTS__TERM_TYPE_ALT_SAMPLE_PERIOD:
+		case PARSE_EVENTS__TERM_TYPE_ALT_PERIOD_JITTER:
 		default:
 			break;
 		}
@@ -1323,6 +1337,7 @@  static int get_config_chgs(struct perf_pmu *pmu, struct parse_events_terms *head
 		case PARSE_EVENTS__TERM_TYPE_LEGACY_CACHE:
 		case PARSE_EVENTS__TERM_TYPE_HARDWARE:
 		case PARSE_EVENTS__TERM_TYPE_ALT_SAMPLE_PERIOD:
+		case PARSE_EVENTS__TERM_TYPE_ALT_PERIOD_JITTER:
 		default:
 			break;
 		}
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index f1482361321a..9b9649da1932 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -80,7 +80,8 @@  enum parse_events__term_type {
 	PARSE_EVENTS__TERM_TYPE_LEGACY_CACHE,
 	PARSE_EVENTS__TERM_TYPE_HARDWARE,
 	PARSE_EVENTS__TERM_TYPE_ALT_SAMPLE_PERIOD,
-#define	__PARSE_EVENTS__TERM_TYPE_NR (PARSE_EVENTS__TERM_TYPE_ALT_SAMPLE_PERIOD + 1)
+	PARSE_EVENTS__TERM_TYPE_ALT_PERIOD_JITTER,
+#define	__PARSE_EVENTS__TERM_TYPE_NR (PARSE_EVENTS__TERM_TYPE_ALT_PERIOD_JITTER + 1)
 };
 
 struct parse_events_term {
diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l
index 1972a5a696ef..c22e64407d64 100644
--- a/tools/perf/util/parse-events.l
+++ b/tools/perf/util/parse-events.l
@@ -332,6 +332,7 @@  aux-output		{ return term(yyscanner, PARSE_EVENTS__TERM_TYPE_AUX_OUTPUT); }
 aux-sample-size		{ return term(yyscanner, PARSE_EVENTS__TERM_TYPE_AUX_SAMPLE_SIZE); }
 metric-id		{ return term(yyscanner, PARSE_EVENTS__TERM_TYPE_METRIC_ID); }
 alt-period		{ return term(yyscanner, PARSE_EVENTS__TERM_TYPE_ALT_SAMPLE_PERIOD); }
+alt-period-jitter	{ return term(yyscanner, PARSE_EVENTS__TERM_TYPE_ALT_PERIOD_JITTER); }
 cpu-cycles|cycles				{ return hw_term(yyscanner, PERF_COUNT_HW_CPU_CYCLES); }
 stalled-cycles-frontend|idle-cycles-frontend	{ return hw_term(yyscanner, PERF_COUNT_HW_STALLED_CYCLES_FRONTEND); }
 stalled-cycles-backend|idle-cycles-backend	{ return hw_term(yyscanner, PERF_COUNT_HW_STALLED_CYCLES_BACKEND); }
diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index 7615d05e389f..c7a5ee61c436 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -1739,6 +1739,7 @@  int perf_pmu__for_each_format(struct perf_pmu *pmu, void *state, pmu_format_call
 		"aux-output",
 		"aux-sample-size=number",
 		"alt-period=number",
+		"alt-period-jitter=number",
 	};
 	struct perf_pmu_format *format;
 	int ret;