* [PATCH V16 1/7] perf tools: Add aux_start_paused, aux_pause and aux_resume
2024-12-16 7:02 [PATCH V16 0/7] perf/core: Add ability for an event to "pause" or "resume" AUX area tracing Adrian Hunter
@ 2024-12-16 7:02 ` Adrian Hunter
2024-12-16 7:02 ` [PATCH V16 2/7] perf tools: Add aux-action config term Adrian Hunter
` (5 subsequent siblings)
6 siblings, 0 replies; 13+ messages in thread
From: Adrian Hunter @ 2024-12-16 7:02 UTC (permalink / raw)
To: Arnaldo Carvalho de Melo, Namhyung Kim
Cc: Jiri Olsa, Ian Rogers, Kan Liang, Leo Yan, linux-kernel,
linux-perf-users
Add struct perf_event_attr members to support pause and resume of AUX area
tracing.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
---
Changes in V16:
Changes to tools/include/uapi/linux/perf_event.h already applied
tools/perf/util/perf_event_attr_fprintf.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/tools/perf/util/perf_event_attr_fprintf.c b/tools/perf/util/perf_event_attr_fprintf.c
index a73c74b99a3b..c7f3543b9921 100644
--- a/tools/perf/util/perf_event_attr_fprintf.c
+++ b/tools/perf/util/perf_event_attr_fprintf.c
@@ -331,6 +331,9 @@ int perf_event_attr__fprintf(FILE *fp, struct perf_event_attr *attr,
PRINT_ATTRf(sample_max_stack, p_unsigned);
PRINT_ATTRf(aux_sample_size, p_unsigned);
PRINT_ATTRf(sig_data, p_unsigned);
+ PRINT_ATTRf(aux_start_paused, p_unsigned);
+ PRINT_ATTRf(aux_pause, p_unsigned);
+ PRINT_ATTRf(aux_resume, p_unsigned);
return ret;
}
--
2.43.0
^ permalink raw reply related [flat|nested] 13+ messages in thread* [PATCH V16 2/7] perf tools: Add aux-action config term
2024-12-16 7:02 [PATCH V16 0/7] perf/core: Add ability for an event to "pause" or "resume" AUX area tracing Adrian Hunter
2024-12-16 7:02 ` [PATCH V16 1/7] perf tools: Add aux_start_paused, aux_pause and aux_resume Adrian Hunter
@ 2024-12-16 7:02 ` Adrian Hunter
2024-12-16 7:02 ` [PATCH V16 3/7] perf tools: Parse aux-action Adrian Hunter
` (4 subsequent siblings)
6 siblings, 0 replies; 13+ messages in thread
From: Adrian Hunter @ 2024-12-16 7:02 UTC (permalink / raw)
To: Arnaldo Carvalho de Melo, Namhyung Kim
Cc: Jiri Olsa, Ian Rogers, Kan Liang, Leo Yan, linux-kernel,
linux-perf-users
Add a new common config term "aux-action" to use for configuring AUX area
trace pause / resume. The value is a string that will be parsed in a
subsequent patch.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
---
Changes in V7:
Add aux-action to perf_pmu__for_each_format
tools/perf/util/evsel.c | 2 ++
tools/perf/util/evsel_config.h | 1 +
tools/perf/util/parse-events.c | 10 ++++++++++
tools/perf/util/parse-events.h | 1 +
tools/perf/util/parse-events.l | 1 +
tools/perf/util/pmu.c | 1 +
6 files changed, 16 insertions(+)
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index c93311e502cf..a17404b8d0c8 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1151,6 +1151,8 @@ static void evsel__apply_config_terms(struct evsel *evsel,
case EVSEL__CONFIG_TERM_AUX_OUTPUT:
attr->aux_output = term->val.aux_output ? 1 : 0;
break;
+ case EVSEL__CONFIG_TERM_AUX_ACTION:
+ break;
case EVSEL__CONFIG_TERM_AUX_SAMPLE_SIZE:
/* Already applied by auxtrace */
break;
diff --git a/tools/perf/util/evsel_config.h b/tools/perf/util/evsel_config.h
index aee6f808b512..af52a1516d0b 100644
--- a/tools/perf/util/evsel_config.h
+++ b/tools/perf/util/evsel_config.h
@@ -25,6 +25,7 @@ enum evsel_term_type {
EVSEL__CONFIG_TERM_BRANCH,
EVSEL__CONFIG_TERM_PERCORE,
EVSEL__CONFIG_TERM_AUX_OUTPUT,
+ EVSEL__CONFIG_TERM_AUX_ACTION,
EVSEL__CONFIG_TERM_AUX_SAMPLE_SIZE,
EVSEL__CONFIG_TERM_CFG_CHG,
};
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 7fc1c36ef2a4..1e23faa364b1 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -793,6 +793,7 @@ const char *parse_events__term_type_str(enum parse_events__term_type term_type)
[PARSE_EVENTS__TERM_TYPE_DRV_CFG] = "driver-config",
[PARSE_EVENTS__TERM_TYPE_PERCORE] = "percore",
[PARSE_EVENTS__TERM_TYPE_AUX_OUTPUT] = "aux-output",
+ [PARSE_EVENTS__TERM_TYPE_AUX_ACTION] = "aux-action",
[PARSE_EVENTS__TERM_TYPE_AUX_SAMPLE_SIZE] = "aux-sample-size",
[PARSE_EVENTS__TERM_TYPE_METRIC_ID] = "metric-id",
[PARSE_EVENTS__TERM_TYPE_RAW] = "raw",
@@ -842,6 +843,7 @@ config_term_avail(enum parse_events__term_type term_type, struct parse_events_er
case PARSE_EVENTS__TERM_TYPE_OVERWRITE:
case PARSE_EVENTS__TERM_TYPE_DRV_CFG:
case PARSE_EVENTS__TERM_TYPE_AUX_OUTPUT:
+ case PARSE_EVENTS__TERM_TYPE_AUX_ACTION:
case PARSE_EVENTS__TERM_TYPE_AUX_SAMPLE_SIZE:
case PARSE_EVENTS__TERM_TYPE_RAW:
case PARSE_EVENTS__TERM_TYPE_LEGACY_CACHE:
@@ -961,6 +963,9 @@ do { \
case PARSE_EVENTS__TERM_TYPE_AUX_OUTPUT:
CHECK_TYPE_VAL(NUM);
break;
+ case PARSE_EVENTS__TERM_TYPE_AUX_ACTION:
+ CHECK_TYPE_VAL(STR);
+ break;
case PARSE_EVENTS__TERM_TYPE_AUX_SAMPLE_SIZE:
CHECK_TYPE_VAL(NUM);
if (term->val.num > UINT_MAX) {
@@ -1078,6 +1083,7 @@ static int config_term_tracepoint(struct perf_event_attr *attr,
case PARSE_EVENTS__TERM_TYPE_OVERWRITE:
case PARSE_EVENTS__TERM_TYPE_NOOVERWRITE:
case PARSE_EVENTS__TERM_TYPE_AUX_OUTPUT:
+ case PARSE_EVENTS__TERM_TYPE_AUX_ACTION:
case PARSE_EVENTS__TERM_TYPE_AUX_SAMPLE_SIZE:
return config_term_common(attr, term, err);
case PARSE_EVENTS__TERM_TYPE_USER:
@@ -1213,6 +1219,9 @@ do { \
ADD_CONFIG_TERM_VAL(AUX_OUTPUT, aux_output,
term->val.num ? 1 : 0, term->weak);
break;
+ case PARSE_EVENTS__TERM_TYPE_AUX_ACTION:
+ ADD_CONFIG_TERM_STR(AUX_ACTION, term->val.str, term->weak);
+ break;
case PARSE_EVENTS__TERM_TYPE_AUX_SAMPLE_SIZE:
ADD_CONFIG_TERM_VAL(AUX_SAMPLE_SIZE, aux_sample_size,
term->val.num, term->weak);
@@ -1275,6 +1284,7 @@ static int get_config_chgs(struct perf_pmu *pmu, struct parse_events_terms *head
case PARSE_EVENTS__TERM_TYPE_DRV_CFG:
case PARSE_EVENTS__TERM_TYPE_PERCORE:
case PARSE_EVENTS__TERM_TYPE_AUX_OUTPUT:
+ case PARSE_EVENTS__TERM_TYPE_AUX_ACTION:
case PARSE_EVENTS__TERM_TYPE_AUX_SAMPLE_SIZE:
case PARSE_EVENTS__TERM_TYPE_METRIC_ID:
case PARSE_EVENTS__TERM_TYPE_RAW:
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index 3f4334ec6231..e176a34ab088 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -74,6 +74,7 @@ enum parse_events__term_type {
PARSE_EVENTS__TERM_TYPE_DRV_CFG,
PARSE_EVENTS__TERM_TYPE_PERCORE,
PARSE_EVENTS__TERM_TYPE_AUX_OUTPUT,
+ PARSE_EVENTS__TERM_TYPE_AUX_ACTION,
PARSE_EVENTS__TERM_TYPE_AUX_SAMPLE_SIZE,
PARSE_EVENTS__TERM_TYPE_METRIC_ID,
PARSE_EVENTS__TERM_TYPE_RAW,
diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l
index 14e5bd856a18..bf7f73548605 100644
--- a/tools/perf/util/parse-events.l
+++ b/tools/perf/util/parse-events.l
@@ -321,6 +321,7 @@ overwrite { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_OVERWRITE); }
no-overwrite { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_NOOVERWRITE); }
percore { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_PERCORE); }
aux-output { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_AUX_OUTPUT); }
+aux-action { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_AUX_ACTION); }
aux-sample-size { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_AUX_SAMPLE_SIZE); }
metric-id { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_METRIC_ID); }
cpu-cycles|cycles { return hw_term(yyscanner, PERF_COUNT_HW_CPU_CYCLES); }
diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index 891c905d08a1..6206c8fe2bf9 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -1773,6 +1773,7 @@ int perf_pmu__for_each_format(struct perf_pmu *pmu, void *state, pmu_format_call
"no-overwrite",
"percore",
"aux-output",
+ "aux-action=(pause|resume|start-paused)",
"aux-sample-size=number",
};
struct perf_pmu_format *format;
--
2.43.0
^ permalink raw reply related [flat|nested] 13+ messages in thread* [PATCH V16 3/7] perf tools: Parse aux-action
2024-12-16 7:02 [PATCH V16 0/7] perf/core: Add ability for an event to "pause" or "resume" AUX area tracing Adrian Hunter
2024-12-16 7:02 ` [PATCH V16 1/7] perf tools: Add aux_start_paused, aux_pause and aux_resume Adrian Hunter
2024-12-16 7:02 ` [PATCH V16 2/7] perf tools: Add aux-action config term Adrian Hunter
@ 2024-12-16 7:02 ` Adrian Hunter
2024-12-16 7:02 ` [PATCH V16 4/7] perf tools: Add missing_features for aux_start_paused, aux_pause, aux_resume Adrian Hunter
` (3 subsequent siblings)
6 siblings, 0 replies; 13+ messages in thread
From: Adrian Hunter @ 2024-12-16 7:02 UTC (permalink / raw)
To: Arnaldo Carvalho de Melo, Namhyung Kim
Cc: Jiri Olsa, Ian Rogers, Kan Liang, Leo Yan, linux-kernel,
linux-perf-users
Add parsing for aux-action to accept "pause", "resume" or "start-paused"
values.
"start-paused" is valid only for AUX area events.
"pause" and "resume" are valid only for events grouped with an AUX area
event as the group leader. However, like with aux-output, the events
will be automatically grouped if they are not currently in a group, and
the AUX area event precedes the other events.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
---
Changes in V8:
Fix clang warning:
util/auxtrace.c:821:7: error: missing field 'aux_action' initializer [-Werror,-Wmissing-field-initializers]
821 | {NULL},
| ^
tools/perf/Documentation/perf-record.txt | 4 ++
tools/perf/builtin-record.c | 4 +-
tools/perf/util/auxtrace.c | 67 ++++++++++++++++++++++--
tools/perf/util/auxtrace.h | 6 ++-
tools/perf/util/evsel.c | 1 +
5 files changed, 74 insertions(+), 8 deletions(-)
diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt
index 242223240a08..80686d590de2 100644
--- a/tools/perf/Documentation/perf-record.txt
+++ b/tools/perf/Documentation/perf-record.txt
@@ -68,6 +68,10 @@ OPTIONS
like this: name=\'CPU_CLK_UNHALTED.THREAD:cmask=0x1\'.
- 'aux-output': Generate AUX records instead of events. This requires
that an AUX area event is also provided.
+ - 'aux-action': "pause" or "resume" to pause or resume an AUX
+ area event (the group leader) when this event occurs.
+ "start-paused" on an AUX area event itself, will
+ start in a paused state.
- 'aux-sample-size': Set sample size for AUX area sampling. If the
'--aux-sample' option has been used, set aux-sample-size=0 to disable
AUX area sampling for the event.
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 0b637cea4850..5db1aedf48df 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -860,7 +860,9 @@ static int record__auxtrace_init(struct record *rec)
if (err)
return err;
- auxtrace_regroup_aux_output(rec->evlist);
+ err = auxtrace_parse_aux_action(rec->evlist);
+ if (err)
+ return err;
return auxtrace_parse_filters(rec->evlist);
}
diff --git a/tools/perf/util/auxtrace.c b/tools/perf/util/auxtrace.c
index ca8682966fae..4d1633d87eff 100644
--- a/tools/perf/util/auxtrace.c
+++ b/tools/perf/util/auxtrace.c
@@ -810,19 +810,76 @@ int auxtrace_parse_sample_options(struct auxtrace_record *itr,
return auxtrace_validate_aux_sample_size(evlist, opts);
}
-void auxtrace_regroup_aux_output(struct evlist *evlist)
+static struct aux_action_opt {
+ const char *str;
+ u32 aux_action;
+ bool aux_event_opt;
+} aux_action_opts[] = {
+ {"start-paused", BIT(0), true},
+ {"pause", BIT(1), false},
+ {"resume", BIT(2), false},
+ {.str = NULL},
+};
+
+static const struct aux_action_opt *auxtrace_parse_aux_action_str(const char *str)
+{
+ const struct aux_action_opt *opt;
+
+ if (!str)
+ return NULL;
+
+ for (opt = aux_action_opts; opt->str; opt++)
+ if (!strcmp(str, opt->str))
+ return opt;
+
+ return NULL;
+}
+
+int auxtrace_parse_aux_action(struct evlist *evlist)
{
- struct evsel *evsel, *aux_evsel = NULL;
struct evsel_config_term *term;
+ struct evsel *aux_evsel = NULL;
+ struct evsel *evsel;
evlist__for_each_entry(evlist, evsel) {
- if (evsel__is_aux_event(evsel))
+ bool is_aux_event = evsel__is_aux_event(evsel);
+ const struct aux_action_opt *opt;
+
+ if (is_aux_event)
aux_evsel = evsel;
- term = evsel__get_config_term(evsel, AUX_OUTPUT);
+ term = evsel__get_config_term(evsel, AUX_ACTION);
+ if (!term) {
+ if (evsel__get_config_term(evsel, AUX_OUTPUT))
+ goto regroup;
+ continue;
+ }
+ opt = auxtrace_parse_aux_action_str(term->val.str);
+ if (!opt) {
+ pr_err("Bad aux-action '%s'\n", term->val.str);
+ return -EINVAL;
+ }
+ if (opt->aux_event_opt && !is_aux_event) {
+ pr_err("aux-action '%s' can only be used with AUX area event\n",
+ term->val.str);
+ return -EINVAL;
+ }
+ if (!opt->aux_event_opt && is_aux_event) {
+ pr_err("aux-action '%s' cannot be used for AUX area event itself\n",
+ term->val.str);
+ return -EINVAL;
+ }
+ evsel->core.attr.aux_action = opt->aux_action;
+regroup:
/* If possible, group with the AUX event */
- if (term && aux_evsel)
+ if (aux_evsel)
evlist__regroup(evlist, aux_evsel, evsel);
+ if (!evsel__is_aux_event(evsel__leader(evsel))) {
+ pr_err("Events with aux-action must have AUX area event group leader\n");
+ return -EINVAL;
+ }
}
+
+ return 0;
}
struct auxtrace_record *__weak
diff --git a/tools/perf/util/auxtrace.h b/tools/perf/util/auxtrace.h
index dddaf4f3ffed..b0db84d27b25 100644
--- a/tools/perf/util/auxtrace.h
+++ b/tools/perf/util/auxtrace.h
@@ -578,7 +578,7 @@ int auxtrace_parse_snapshot_options(struct auxtrace_record *itr,
int auxtrace_parse_sample_options(struct auxtrace_record *itr,
struct evlist *evlist,
struct record_opts *opts, const char *str);
-void auxtrace_regroup_aux_output(struct evlist *evlist);
+int auxtrace_parse_aux_action(struct evlist *evlist);
int auxtrace_record__options(struct auxtrace_record *itr,
struct evlist *evlist,
struct record_opts *opts);
@@ -799,8 +799,10 @@ int auxtrace_parse_sample_options(struct auxtrace_record *itr __maybe_unused,
}
static inline
-void auxtrace_regroup_aux_output(struct evlist *evlist __maybe_unused)
+int auxtrace_parse_aux_action(struct evlist *evlist __maybe_unused)
{
+ pr_err("AUX area tracing not supported\n");
+ return -EINVAL;
}
static inline
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index a17404b8d0c8..0a1b797d1f00 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1152,6 +1152,7 @@ static void evsel__apply_config_terms(struct evsel *evsel,
attr->aux_output = term->val.aux_output ? 1 : 0;
break;
case EVSEL__CONFIG_TERM_AUX_ACTION:
+ /* Already applied by auxtrace */
break;
case EVSEL__CONFIG_TERM_AUX_SAMPLE_SIZE:
/* Already applied by auxtrace */
--
2.43.0
^ permalink raw reply related [flat|nested] 13+ messages in thread* [PATCH V16 4/7] perf tools: Add missing_features for aux_start_paused, aux_pause, aux_resume
2024-12-16 7:02 [PATCH V16 0/7] perf/core: Add ability for an event to "pause" or "resume" AUX area tracing Adrian Hunter
` (2 preceding siblings ...)
2024-12-16 7:02 ` [PATCH V16 3/7] perf tools: Parse aux-action Adrian Hunter
@ 2024-12-16 7:02 ` Adrian Hunter
2024-12-16 7:02 ` [PATCH V16 5/7] perf intel-pt: Improve man page format Adrian Hunter
` (2 subsequent siblings)
6 siblings, 0 replies; 13+ messages in thread
From: Adrian Hunter @ 2024-12-16 7:02 UTC (permalink / raw)
To: Arnaldo Carvalho de Melo, Namhyung Kim
Cc: Jiri Olsa, Ian Rogers, Kan Liang, Leo Yan, linux-kernel,
linux-perf-users
Display "feature is not supported" error message if aux_start_paused,
aux_pause or aux_resume result in a perf_event_open() error.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
Changes in V15:
Re-base on new API probe method of missing feature detection
and add probe for aux_action.
Changes in V13:
Add error message also in EOPNOTSUPP case (Leo)
tools/perf/util/evsel.c | 98 ++++++++++++++++++++++++++++++++++++-----
tools/perf/util/evsel.h | 1 +
2 files changed, 87 insertions(+), 12 deletions(-)
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 0a1b797d1f00..f6bf845808d6 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -2145,16 +2145,17 @@ int evsel__prepare_open(struct evsel *evsel, struct perf_cpu_map *cpus,
return err;
}
-static bool has_attr_feature(struct perf_event_attr *attr, unsigned long flags)
+static bool __has_attr_feature(struct perf_event_attr *attr,
+ struct perf_cpu cpu, unsigned long flags)
{
- int fd = syscall(SYS_perf_event_open, attr, /*pid=*/0, /*cpu=*/-1,
+ int fd = syscall(SYS_perf_event_open, attr, /*pid=*/0, cpu.cpu,
/*group_fd=*/-1, flags);
close(fd);
if (fd < 0) {
attr->exclude_kernel = 1;
- fd = syscall(SYS_perf_event_open, attr, /*pid=*/0, /*cpu=*/-1,
+ fd = syscall(SYS_perf_event_open, attr, /*pid=*/0, cpu.cpu,
/*group_fd=*/-1, flags);
close(fd);
}
@@ -2162,7 +2163,7 @@ static bool has_attr_feature(struct perf_event_attr *attr, unsigned long flags)
if (fd < 0) {
attr->exclude_hv = 1;
- fd = syscall(SYS_perf_event_open, attr, /*pid=*/0, /*cpu=*/-1,
+ fd = syscall(SYS_perf_event_open, attr, /*pid=*/0, cpu.cpu,
/*group_fd=*/-1, flags);
close(fd);
}
@@ -2170,7 +2171,7 @@ static bool has_attr_feature(struct perf_event_attr *attr, unsigned long flags)
if (fd < 0) {
attr->exclude_guest = 1;
- fd = syscall(SYS_perf_event_open, attr, /*pid=*/0, /*cpu=*/-1,
+ fd = syscall(SYS_perf_event_open, attr, /*pid=*/0, cpu.cpu,
/*group_fd=*/-1, flags);
close(fd);
}
@@ -2182,6 +2183,13 @@ static bool has_attr_feature(struct perf_event_attr *attr, unsigned long flags)
return fd >= 0;
}
+static bool has_attr_feature(struct perf_event_attr *attr, unsigned long flags)
+{
+ struct perf_cpu cpu = {.cpu = -1};
+
+ return __has_attr_feature(attr, cpu, flags);
+}
+
static void evsel__detect_missing_pmu_features(struct evsel *evsel)
{
struct perf_event_attr attr = {
@@ -2270,7 +2278,65 @@ static void evsel__detect_missing_brstack_features(struct evsel *evsel)
errno = old_errno;
}
-static bool evsel__detect_missing_features(struct evsel *evsel)
+static bool evsel__probe_aux_action(struct evsel *evsel, struct perf_cpu cpu)
+{
+ struct perf_event_attr attr = evsel->core.attr;
+ int old_errno = errno;
+
+ attr.disabled = 1;
+ attr.aux_start_paused = 1;
+
+ if (__has_attr_feature(&attr, cpu, /*flags=*/0)) {
+ errno = old_errno;
+ return true;
+ }
+
+ /*
+ * EOPNOTSUPP means the kernel supports the feature but the PMU does
+ * not, so keep that distinction if possible.
+ */
+ if (errno != EOPNOTSUPP)
+ errno = old_errno;
+
+ return false;
+}
+
+static void evsel__detect_missing_aux_action_feature(struct evsel *evsel, struct perf_cpu cpu)
+{
+ static bool detection_done;
+ struct evsel *leader;
+
+ /*
+ * Don't bother probing aux_action if it is not being used or has been
+ * probed before.
+ */
+ if (!evsel->core.attr.aux_action || detection_done)
+ return;
+
+ detection_done = true;
+
+ /*
+ * The leader is an AUX area event. If it has failed, assume the feature
+ * is not supported.
+ */
+ leader = evsel__leader(evsel);
+ if (evsel == leader) {
+ perf_missing_features.aux_action = true;
+ return;
+ }
+
+ /*
+ * AUX area event with aux_action must have been opened successfully
+ * already, so feature is supported.
+ */
+ if (leader->core.attr.aux_action)
+ return;
+
+ if (!evsel__probe_aux_action(leader, cpu))
+ perf_missing_features.aux_action = true;
+}
+
+static bool evsel__detect_missing_features(struct evsel *evsel, struct perf_cpu cpu)
{
static bool detection_done = false;
struct perf_event_attr attr = {
@@ -2280,6 +2346,8 @@ static bool evsel__detect_missing_features(struct evsel *evsel)
};
int old_errno;
+ evsel__detect_missing_aux_action_feature(evsel, cpu);
+
evsel__detect_missing_pmu_features(evsel);
if (evsel__has_br_stack(evsel))
@@ -2494,6 +2562,7 @@ static int evsel__open_cpu(struct evsel *evsel, struct perf_cpu_map *cpus,
int idx, thread, nthreads;
int pid = -1, err, old_errno;
enum rlimit_action set_rlimit = NO_CHANGE;
+ struct perf_cpu cpu;
if (evsel__is_retire_lat(evsel))
return tpebs_start(evsel->evlist);
@@ -2531,6 +2600,7 @@ static int evsel__open_cpu(struct evsel *evsel, struct perf_cpu_map *cpus,
}
for (idx = start_cpu_map_idx; idx < end_cpu_map_idx; idx++) {
+ cpu = perf_cpu_map__cpu(cpus, idx);
for (thread = 0; thread < nthreads; thread++) {
int fd, group_fd;
@@ -2551,10 +2621,9 @@ static int evsel__open_cpu(struct evsel *evsel, struct perf_cpu_map *cpus,
/* Debug message used by test scripts */
pr_debug2_peo("sys_perf_event_open: pid %d cpu %d group_fd %d flags %#lx",
- pid, perf_cpu_map__cpu(cpus, idx).cpu, group_fd, evsel->open_flags);
+ pid, cpu.cpu, group_fd, evsel->open_flags);
- fd = sys_perf_event_open(&evsel->core.attr, pid,
- perf_cpu_map__cpu(cpus, idx).cpu,
+ fd = sys_perf_event_open(&evsel->core.attr, pid, cpu.cpu,
group_fd, evsel->open_flags);
FD(evsel, idx, thread) = fd;
@@ -2570,8 +2639,7 @@ static int evsel__open_cpu(struct evsel *evsel, struct perf_cpu_map *cpus,
bpf_counter__install_pe(evsel, idx, fd);
if (unlikely(test_attr__enabled())) {
- test_attr__open(&evsel->core.attr, pid,
- perf_cpu_map__cpu(cpus, idx),
+ test_attr__open(&evsel->core.attr, pid, cpu,
fd, group_fd, evsel->open_flags);
}
@@ -2626,7 +2694,7 @@ static int evsel__open_cpu(struct evsel *evsel, struct perf_cpu_map *cpus,
if (err == -EMFILE && rlimit__increase_nofile(&set_rlimit))
goto retry_open;
- if (err == -EINVAL && evsel__detect_missing_features(evsel))
+ if (err == -EINVAL && evsel__detect_missing_features(evsel, cpu))
goto fallback_missing_features;
if (evsel__precise_ip_fallback(evsel))
@@ -3585,6 +3653,10 @@ int evsel__open_strerror(struct evsel *evsel, struct target *target,
return scnprintf(msg, size,
"%s: PMU Hardware doesn't support 'aux_output' feature",
evsel__name(evsel));
+ if (evsel->core.attr.aux_action)
+ return scnprintf(msg, size,
+ "%s: PMU Hardware doesn't support 'aux_action' feature",
+ evsel__name(evsel));
if (evsel->core.attr.sample_period != 0)
return scnprintf(msg, size,
"%s: PMU Hardware doesn't support sampling/overflow-interrupts. Try 'perf stat'",
@@ -3615,6 +3687,8 @@ int evsel__open_strerror(struct evsel *evsel, struct target *target,
return scnprintf(msg, size, "clockid feature not supported.");
if (perf_missing_features.clockid_wrong)
return scnprintf(msg, size, "wrong clockid (%d).", clockid);
+ if (perf_missing_features.aux_action)
+ return scnprintf(msg, size, "The 'aux_action' feature is not supported, update the kernel.");
if (perf_missing_features.aux_output)
return scnprintf(msg, size, "The 'aux_output' feature is not supported, update the kernel.");
if (!target__has_cpu(target))
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index 93b6244ec302..76749bb0e1a5 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -207,6 +207,7 @@ struct perf_missing_features {
bool weight_struct;
bool read_lost;
bool branch_counters;
+ bool aux_action;
bool inherit_sample_read;
};
--
2.43.0
^ permalink raw reply related [flat|nested] 13+ messages in thread* [PATCH V16 5/7] perf intel-pt: Improve man page format
2024-12-16 7:02 [PATCH V16 0/7] perf/core: Add ability for an event to "pause" or "resume" AUX area tracing Adrian Hunter
` (3 preceding siblings ...)
2024-12-16 7:02 ` [PATCH V16 4/7] perf tools: Add missing_features for aux_start_paused, aux_pause, aux_resume Adrian Hunter
@ 2024-12-16 7:02 ` Adrian Hunter
2024-12-16 7:02 ` [PATCH V16 6/7] perf intel-pt: Add documentation for pause / resume Adrian Hunter
2024-12-16 7:02 ` [PATCH V16 7/7] perf intel-pt: Add a test " Adrian Hunter
6 siblings, 0 replies; 13+ messages in thread
From: Adrian Hunter @ 2024-12-16 7:02 UTC (permalink / raw)
To: Arnaldo Carvalho de Melo, Namhyung Kim
Cc: Jiri Olsa, Ian Rogers, Kan Liang, Leo Yan, linux-kernel,
linux-perf-users
Improve format of config terms and section references.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
---
tools/perf/Documentation/perf-intel-pt.txt | 486 +++++++++++----------
1 file changed, 267 insertions(+), 219 deletions(-)
diff --git a/tools/perf/Documentation/perf-intel-pt.txt b/tools/perf/Documentation/perf-intel-pt.txt
index 59ab1ff9d75f..ad39bf20f862 100644
--- a/tools/perf/Documentation/perf-intel-pt.txt
+++ b/tools/perf/Documentation/perf-intel-pt.txt
@@ -151,7 +151,7 @@ displayed as follows:
There are two ways that instructions-per-cycle (IPC) can be calculated depending
on the recording.
-If the 'cyc' config term (see config terms section below) was used, then IPC
+If the 'cyc' config term (see <<_config_terms,config terms>> section below) was used, then IPC
and cycle events are calculated using the cycle count from CYC packets, otherwise
MTC packets are used - refer to the 'mtc' config term. When MTC is used, however,
the values are less accurate because the timing is less accurate.
@@ -239,7 +239,7 @@ which is the same as
-e intel_pt/tsc=1,noretcomp=0/
-Note there are now new config terms - see section 'config terms' further below.
+Note there are other config terms - see section <<_config_terms,config terms>> further below.
The config terms are listed in /sys/devices/intel_pt/format. They are bit
fields within the config member of the struct perf_event_attr which is
@@ -311,217 +311,264 @@ perf_event_attr is displayed if the -vv option is used e.g.
config terms
~~~~~~~~~~~~
-The June 2015 version of Intel 64 and IA-32 Architectures Software Developer
-Manuals, Chapter 36 Intel Processor Trace, defined new Intel PT features.
-Some of the features are reflect in new config terms. All the config terms are
-described below.
-
-tsc Always supported. Produces TSC timestamp packets to provide
- timing information. In some cases it is possible to decode
- without timing information, for example a per-thread context
- that does not overlap executable memory maps.
-
- The default config selects tsc (i.e. tsc=1).
-
-noretcomp Always supported. Disables "return compression" so a TIP packet
- is produced when a function returns. Causes more packets to be
- produced but might make decoding more reliable.
-
- The default config does not select noretcomp (i.e. noretcomp=0).
-
-psb_period Allows the frequency of PSB packets to be specified.
-
- The PSB packet is a synchronization packet that provides a
- starting point for decoding or recovery from errors.
-
- Support for psb_period is indicated by:
-
- /sys/bus/event_source/devices/intel_pt/caps/psb_cyc
-
- which contains "1" if the feature is supported and "0"
- otherwise.
-
- Valid values are given by:
-
- /sys/bus/event_source/devices/intel_pt/caps/psb_periods
-
- which contains a hexadecimal value, the bits of which represent
- valid values e.g. bit 2 set means value 2 is valid.
-
- The psb_period value is converted to the approximate number of
- trace bytes between PSB packets as:
-
- 2 ^ (value + 11)
-
- e.g. value 3 means 16KiB bytes between PSBs
-
- If an invalid value is entered, the error message
- will give a list of valid values e.g.
-
- $ perf record -e intel_pt/psb_period=15/u uname
- Invalid psb_period for intel_pt. Valid values are: 0-5
-
- If MTC packets are selected, the default config selects a value
- of 3 (i.e. psb_period=3) or the nearest lower value that is
- supported (0 is always supported). Otherwise the default is 0.
-
- If decoding is expected to be reliable and the buffer is large
- then a large PSB period can be used.
-
- Because a TSC packet is produced with PSB, the PSB period can
- also affect the granularity to timing information in the absence
- of MTC or CYC.
-
-mtc Produces MTC timing packets.
-
- MTC packets provide finer grain timestamp information than TSC
- packets. MTC packets record time using the hardware crystal
- clock (CTC) which is related to TSC packets using a TMA packet.
-
- Support for this feature is indicated by:
-
- /sys/bus/event_source/devices/intel_pt/caps/mtc
-
- which contains "1" if the feature is supported and
- "0" otherwise.
-
- The frequency of MTC packets can also be specified - see
- mtc_period below.
-
-mtc_period Specifies how frequently MTC packets are produced - see mtc
- above for how to determine if MTC packets are supported.
-
- Valid values are given by:
-
- /sys/bus/event_source/devices/intel_pt/caps/mtc_periods
-
- which contains a hexadecimal value, the bits of which represent
- valid values e.g. bit 2 set means value 2 is valid.
-
- The mtc_period value is converted to the MTC frequency as:
-
- CTC-frequency / (2 ^ value)
-
- e.g. value 3 means one eighth of CTC-frequency
-
- Where CTC is the hardware crystal clock, the frequency of which
- can be related to TSC via values provided in cpuid leaf 0x15.
-
- If an invalid value is entered, the error message
- will give a list of valid values e.g.
-
- $ perf record -e intel_pt/mtc_period=15/u uname
- Invalid mtc_period for intel_pt. Valid values are: 0,3,6,9
-
- The default value is 3 or the nearest lower value
- that is supported (0 is always supported).
-
-cyc Produces CYC timing packets.
-
- CYC packets provide even finer grain timestamp information than
- MTC and TSC packets. A CYC packet contains the number of CPU
- cycles since the last CYC packet. Unlike MTC and TSC packets,
- CYC packets are only sent when another packet is also sent.
-
- Support for this feature is indicated by:
-
- /sys/bus/event_source/devices/intel_pt/caps/psb_cyc
-
- which contains "1" if the feature is supported and
- "0" otherwise.
-
- The number of CYC packets produced can be reduced by specifying
- a threshold - see cyc_thresh below.
-
-cyc_thresh Specifies how frequently CYC packets are produced - see cyc
- above for how to determine if CYC packets are supported.
-
- Valid cyc_thresh values are given by:
-
- /sys/bus/event_source/devices/intel_pt/caps/cycle_thresholds
-
- which contains a hexadecimal value, the bits of which represent
- valid values e.g. bit 2 set means value 2 is valid.
-
- The cyc_thresh value represents the minimum number of CPU cycles
- that must have passed before a CYC packet can be sent. The
- number of CPU cycles is:
-
- 2 ^ (value - 1)
-
- e.g. value 4 means 8 CPU cycles must pass before a CYC packet
- can be sent. Note a CYC packet is still only sent when another
- packet is sent, not at, e.g. every 8 CPU cycles.
-
- If an invalid value is entered, the error message
- will give a list of valid values e.g.
-
- $ perf record -e intel_pt/cyc,cyc_thresh=15/u uname
- Invalid cyc_thresh for intel_pt. Valid values are: 0-12
-
- CYC packets are not requested by default.
-
-pt Specifies pass-through which enables the 'branch' config term.
-
- The default config selects 'pt' if it is available, so a user will
- never need to specify this term.
-
-branch Enable branch tracing. Branch tracing is enabled by default so to
- disable branch tracing use 'branch=0'.
-
- The default config selects 'branch' if it is available.
-
-ptw Enable PTWRITE packets which are produced when a ptwrite instruction
- is executed.
-
- Support for this feature is indicated by:
-
- /sys/bus/event_source/devices/intel_pt/caps/ptwrite
-
- which contains "1" if the feature is supported and
- "0" otherwise.
-
- As an alternative, refer to "Emulated PTWRITE" further below.
-
-fup_on_ptw Enable a FUP packet to follow the PTWRITE packet. The FUP packet
- provides the address of the ptwrite instruction. In the absence of
- fup_on_ptw, the decoder will use the address of the previous branch
- if branch tracing is enabled, otherwise the address will be zero.
- Note that fup_on_ptw will work even when branch tracing is disabled.
-
-pwr_evt Enable power events. The power events provide information about
- changes to the CPU C-state.
-
- Support for this feature is indicated by:
-
- /sys/bus/event_source/devices/intel_pt/caps/power_event_trace
-
- which contains "1" if the feature is supported and
- "0" otherwise.
-
-event Enable Event Trace. The events provide information about asynchronous
- events.
-
- Support for this feature is indicated by:
-
- /sys/bus/event_source/devices/intel_pt/caps/event_trace
-
- which contains "1" if the feature is supported and
- "0" otherwise.
-
-notnt Disable TNT packets. Without TNT packets, it is not possible to walk
- executable code to reconstruct control flow, however FUP, TIP, TIP.PGE
- and TIP.PGD packets still indicate asynchronous control flow, and (if
- return compression is disabled - see noretcomp) return statements.
- The advantage of eliminating TNT packets is reducing the size of the
- trace and corresponding tracing overhead.
-
- Support for this feature is indicated by:
-
- /sys/bus/event_source/devices/intel_pt/caps/tnt_disable
-
- which contains "1" if the feature is supported and
- "0" otherwise.
+Config terms are parameters specified with the -e intel_pt// event option,
+for example:
+
+ -e intel_pt/cyc/
+
+which selects cycle accurate mode. Each config term can have a value which
+defaults to 1, so the above is the same as:
+
+ -e intel_pt/cyc=1/
+
+Some terms are set by default, so must be set to 0 to turn them off. For
+example, to turn off branch tracing:
+
+ -e intel_pt/branch=0/
+
+Multiple config terms are separated by commas, for example:
+
+ -e intel_pt/cyc,mtc_period=9/
+
+There are also common config terms, see linkperf:perf-record[1] documentation.
+
+Intel PT config terms are described below.
+
+*tsc*::
+Always supported. Produces TSC timestamp packets to provide
+timing information. In some cases it is possible to decode
+without timing information, for example a per-thread context
+that does not overlap executable memory maps.
++
+The default config selects tsc (i.e. tsc=1).
+
+*noretcomp*::
+Always supported. Disables "return compression" so a TIP packet
+is produced when a function returns. Causes more packets to be
+produced but might make decoding more reliable.
++
+The default config does not select noretcomp (i.e. noretcomp=0).
+
+*psb_period*::
+Allows the frequency of PSB packets to be specified.
++
+The PSB packet is a synchronization packet that provides a
+starting point for decoding or recovery from errors.
++
+Support for psb_period is indicated by:
++
+ /sys/bus/event_source/devices/intel_pt/caps/psb_cyc
++
+which contains "1" if the feature is supported and "0"
+otherwise.
++
+Valid values are given by:
++
+ /sys/bus/event_source/devices/intel_pt/caps/psb_periods
++
+which contains a hexadecimal value, the bits of which represent
+valid values e.g. bit 2 set means value 2 is valid.
++
+The psb_period value is converted to the approximate number of
+trace bytes between PSB packets as:
++
+ 2 ^ (value + 11)
++
+e.g. value 3 means 16KiB bytes between PSBs
++
+If an invalid value is entered, the error message
+will give a list of valid values e.g.
++
+ $ perf record -e intel_pt/psb_period=15/u uname
+ Invalid psb_period for intel_pt. Valid values are: 0-5
++
+If MTC packets are selected, the default config selects a value
+of 3 (i.e. psb_period=3) or the nearest lower value that is
+supported (0 is always supported). Otherwise the default is 0.
++
+If decoding is expected to be reliable and the buffer is large
+then a large PSB period can be used.
++
+Because a TSC packet is produced with PSB, the PSB period can
+also affect the granularity to timing information in the absence
+of MTC or CYC.
+
+*mtc*::
+Produces MTC timing packets.
++
+MTC packets provide finer grain timestamp information than TSC
+packets. MTC packets record time using the hardware crystal
+clock (CTC) which is related to TSC packets using a TMA packet.
++
+Support for this feature is indicated by:
++
+ /sys/bus/event_source/devices/intel_pt/caps/mtc
++
+which contains "1" if the feature is supported and
+"0" otherwise.
++
+The frequency of MTC packets can also be specified - see
+mtc_period below.
+
+*mtc_period*::
+Specifies how frequently MTC packets are produced - see mtc
+above for how to determine if MTC packets are supported.
++
+Valid values are given by:
++
+ /sys/bus/event_source/devices/intel_pt/caps/mtc_periods
++
+which contains a hexadecimal value, the bits of which represent
+valid values e.g. bit 2 set means value 2 is valid.
++
+The mtc_period value is converted to the MTC frequency as:
+
+ CTC-frequency / (2 ^ value)
++
+e.g. value 3 means one eighth of CTC-frequency
++
+Where CTC is the hardware crystal clock, the frequency of which
+can be related to TSC via values provided in cpuid leaf 0x15.
++
+If an invalid value is entered, the error message
+will give a list of valid values e.g.
++
+ $ perf record -e intel_pt/mtc_period=15/u uname
+ Invalid mtc_period for intel_pt. Valid values are: 0,3,6,9
++
+The default value is 3 or the nearest lower value
+that is supported (0 is always supported).
+
+*cyc*::
+Produces CYC timing packets.
++
+CYC packets provide even finer grain timestamp information than
+MTC and TSC packets. A CYC packet contains the number of CPU
+cycles since the last CYC packet. Unlike MTC and TSC packets,
+CYC packets are only sent when another packet is also sent.
++
+Support for this feature is indicated by:
++
+ /sys/bus/event_source/devices/intel_pt/caps/psb_cyc
++
+which contains "1" if the feature is supported and
+"0" otherwise.
++
+The number of CYC packets produced can be reduced by specifying
+a threshold - see cyc_thresh below.
+
+*cyc_thresh*::
+Specifies how frequently CYC packets are produced - see cyc
+above for how to determine if CYC packets are supported.
++
+Valid cyc_thresh values are given by:
++
+ /sys/bus/event_source/devices/intel_pt/caps/cycle_thresholds
++
+which contains a hexadecimal value, the bits of which represent
+valid values e.g. bit 2 set means value 2 is valid.
++
+The cyc_thresh value represents the minimum number of CPU cycles
+that must have passed before a CYC packet can be sent. The
+number of CPU cycles is:
++
+ 2 ^ (value - 1)
++
+e.g. value 4 means 8 CPU cycles must pass before a CYC packet
+can be sent. Note a CYC packet is still only sent when another
+packet is sent, not at, e.g. every 8 CPU cycles.
++
+If an invalid value is entered, the error message
+will give a list of valid values e.g.
++
+ $ perf record -e intel_pt/cyc,cyc_thresh=15/u uname
+ Invalid cyc_thresh for intel_pt. Valid values are: 0-12
++
+CYC packets are not requested by default.
+
+*pt*::
+Specifies pass-through which enables the 'branch' config term.
++
+The default config selects 'pt' if it is available, so a user will
+never need to specify this term.
+
+*branch*::
+Enable branch tracing. Branch tracing is enabled by default so to
+disable branch tracing use 'branch=0'.
++
+The default config selects 'branch' if it is available.
+
+*ptw*::
+Enable PTWRITE packets which are produced when a ptwrite instruction
+is executed.
++
+Support for this feature is indicated by:
++
+ /sys/bus/event_source/devices/intel_pt/caps/ptwrite
++
+which contains "1" if the feature is supported and
+"0" otherwise.
++
+As an alternative, refer to "Emulated PTWRITE" further below.
+
+*fup_on_ptw*::
+Enable a FUP packet to follow the PTWRITE packet. The FUP packet
+provides the address of the ptwrite instruction. In the absence of
+fup_on_ptw, the decoder will use the address of the previous branch
+if branch tracing is enabled, otherwise the address will be zero.
+Note that fup_on_ptw will work even when branch tracing is disabled.
+
+*pwr_evt*::
+Enable power events. The power events provide information about
+changes to the CPU C-state.
++
+Support for this feature is indicated by:
++
+ /sys/bus/event_source/devices/intel_pt/caps/power_event_trace
++
+which contains "1" if the feature is supported and
+"0" otherwise.
+
+*event*::
+Enable Event Trace. The events provide information about asynchronous
+events.
++
+Support for this feature is indicated by:
++
+ /sys/bus/event_source/devices/intel_pt/caps/event_trace
++
+which contains "1" if the feature is supported and
+"0" otherwise.
+
+*notnt*::
+Disable TNT packets. Without TNT packets, it is not possible to walk
+executable code to reconstruct control flow, however FUP, TIP, TIP.PGE
+and TIP.PGD packets still indicate asynchronous control flow, and (if
+return compression is disabled - see noretcomp) return statements.
+The advantage of eliminating TNT packets is reducing the size of the
+trace and corresponding tracing overhead.
++
+Support for this feature is indicated by:
++
+ /sys/bus/event_source/devices/intel_pt/caps/tnt_disable
++
+which contains "1" if the feature is supported and
+"0" otherwise.
+
+
+config terms on other events
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Some Intel PT features work with other events, features such as AUX area sampling
+and PEBS-via-PT. In those cases, the other events can have config terms below:
+
+*aux-sample-size*::
+ Used to set the AUX area sample size, refer to the section
+ <<_aux_area_sampling_option,AUX area sampling option>>
+
+*aux-output*::
+ Used to select PEBS-via-PT, refer to the
+ section <<_pebs_via_intel_pt,PEBS via Intel PT>>
AUX area sampling option
@@ -596,7 +643,8 @@ The default snapshot size is the auxtrace mmap size. If neither auxtrace mmap s
nor snapshot size is specified, then the default is 4MiB for privileged users
(or if /proc/sys/kernel/perf_event_paranoid < 0), 128KiB for unprivileged users.
If an unprivileged user does not specify mmap pages, the mmap pages will be
-reduced as described in the 'new auxtrace mmap size option' section below.
+reduced as described in the <<_new_auxtrace_mmap_size_option,new auxtrace mmap size option>>
+section below.
The snapshot size is displayed if the option -vv is used e.g.
@@ -952,11 +1000,11 @@ transaction start, commit or abort.
Note that "instructions", "cycles", "branches" and "transactions" events
depend on code flow packets which can be disabled by using the config term
-"branch=0". Refer to the config terms section above.
+"branch=0". Refer to the <<_config_terms,config terms>> section above.
"ptwrite" events record the payload of the ptwrite instruction and whether
"fup_on_ptw" was used. "ptwrite" events depend on PTWRITE packets which are
-recorded only if the "ptw" config term was used. Refer to the config terms
+recorded only if the "ptw" config term was used. Refer to the <<_config_terms,config terms>>
section above. perf script "synth" field displays "ptwrite" information like
this: "ip: 0 payload: 0x123456789abcdef0" where "ip" is 1 if "fup_on_ptw" was
used.
@@ -964,7 +1012,7 @@ used.
"Power" events correspond to power event packets and CBR (core-to-bus ratio)
packets. While CBR packets are always recorded when tracing is enabled, power
event packets are recorded only if the "pwr_evt" config term was used. Refer to
-the config terms section above. The power events record information about
+the <<_config_terms,config terms>> section above. The power events record information about
C-state changes, whereas CBR is indicative of CPU frequency. perf script
"event,synth" fields display information like this:
@@ -1120,7 +1168,7 @@ What *will* be decoded with the (single) q option:
- asynchronous branches such as interrupts
- indirect branches
- function return target address *if* the noretcomp config term (refer
- config terms section) was used
+ <<_config_terms,config terms>> section) was used
- start of (control-flow) tracing
- end of (control-flow) tracing, if it is not out of context
- power events, ptwrite, transaction start and abort
@@ -1133,7 +1181,7 @@ Repeating the q option (double-q i.e. qq) results in even faster decoding and ev
less detail. The decoder decodes only extended PSB (PSB+) packets, getting the
instruction pointer if there is a FUP packet within PSB+ (i.e. between PSB and
PSBEND). Note PSB packets occur regularly in the trace based on the psb_period
-config term (refer config terms section). There will be a FUP packet if the
+config term (refer <<_config_terms,config terms>> section). There will be a FUP packet if the
PSB+ occurs while control flow is being traced.
What will *not* be decoded with the qq option:
--
2.43.0
^ permalink raw reply related [flat|nested] 13+ messages in thread* [PATCH V16 6/7] perf intel-pt: Add documentation for pause / resume
2024-12-16 7:02 [PATCH V16 0/7] perf/core: Add ability for an event to "pause" or "resume" AUX area tracing Adrian Hunter
` (4 preceding siblings ...)
2024-12-16 7:02 ` [PATCH V16 5/7] perf intel-pt: Improve man page format Adrian Hunter
@ 2024-12-16 7:02 ` Adrian Hunter
2024-12-16 7:02 ` [PATCH V16 7/7] perf intel-pt: Add a test " Adrian Hunter
6 siblings, 0 replies; 13+ messages in thread
From: Adrian Hunter @ 2024-12-16 7:02 UTC (permalink / raw)
To: Arnaldo Carvalho de Melo, Namhyung Kim
Cc: Jiri Olsa, Ian Rogers, Kan Liang, Leo Yan, linux-kernel,
linux-perf-users
Document the use of aux-action config term and provide a simple example.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
---
Changes in V5:
Added more examples
tools/perf/Documentation/perf-intel-pt.txt | 108 +++++++++++++++++++++
1 file changed, 108 insertions(+)
diff --git a/tools/perf/Documentation/perf-intel-pt.txt b/tools/perf/Documentation/perf-intel-pt.txt
index ad39bf20f862..cc0f37f0fa5a 100644
--- a/tools/perf/Documentation/perf-intel-pt.txt
+++ b/tools/perf/Documentation/perf-intel-pt.txt
@@ -555,6 +555,9 @@ Support for this feature is indicated by:
which contains "1" if the feature is supported and
"0" otherwise.
+*aux-action=start-paused*::
+Start tracing paused, refer to the section <<_pause_or_resume_tracing,Pause or Resume Tracing>>
+
config terms on other events
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -570,6 +573,9 @@ and PEBS-via-PT. In those cases, the other events can have config terms below:
Used to select PEBS-via-PT, refer to the
section <<_pebs_via_intel_pt,PEBS via Intel PT>>
+*aux-action*::
+ Used to pause or resume tracing, refer to the section
+ <<_pause_or_resume_tracing,Pause or Resume Tracing>>
AUX area sampling option
~~~~~~~~~~~~~~~~~~~~~~~~
@@ -1915,6 +1921,108 @@ For pipe mode, the order of events and timestamps can presumably
be messed up.
+Pause or Resume Tracing
+-----------------------
+
+With newer Kernels, it is possible to use other selected events to pause
+or resume Intel PT tracing. This is configured by using the "aux-action"
+config term:
+
+"aux-action=pause" is used with events that are to pause Intel PT tracing.
+
+"aux-action=resume" is used with events that are to resume Intel PT tracing.
+
+"aux-action=start-paused" is used with the Intel PT event to start in a
+paused state.
+
+For example, to trace only the uname system call (sys_newuname) when running the
+command line utility uname:
+
+ $ perf record --kcore -e intel_pt/aux-action=start-paused/k,syscalls:sys_enter_newuname/aux-action=resume/,syscalls:sys_exit_newuname/aux-action=pause/ uname
+ Linux
+ [ perf record: Woken up 1 times to write data ]
+ [ perf record: Captured and wrote 0.043 MB perf.data ]
+ $ perf script --call-trace
+ uname 30805 [000] 24001.058782799: name: 0x7ffc9c1865b0
+ uname 30805 [000] 24001.058784424: psb offs: 0
+ uname 30805 [000] 24001.058784424: cbr: 39 freq: 3904 MHz (139%)
+ uname 30805 [000] 24001.058784629: ([kernel.kallsyms]) debug_smp_processor_id
+ uname 30805 [000] 24001.058784629: ([kernel.kallsyms]) __x64_sys_newuname
+ uname 30805 [000] 24001.058784629: ([kernel.kallsyms]) down_read
+ uname 30805 [000] 24001.058784629: ([kernel.kallsyms]) __cond_resched
+ uname 30805 [000] 24001.058784629: ([kernel.kallsyms]) preempt_count_add
+ uname 30805 [000] 24001.058784629: ([kernel.kallsyms]) in_lock_functions
+ uname 30805 [000] 24001.058784629: ([kernel.kallsyms]) preempt_count_sub
+ uname 30805 [000] 24001.058784629: ([kernel.kallsyms]) up_read
+ uname 30805 [000] 24001.058784629: ([kernel.kallsyms]) preempt_count_add
+ uname 30805 [000] 24001.058784838: ([kernel.kallsyms]) in_lock_functions
+ uname 30805 [000] 24001.058784838: ([kernel.kallsyms]) preempt_count_sub
+ uname 30805 [000] 24001.058784838: ([kernel.kallsyms]) _copy_to_user
+ uname 30805 [000] 24001.058784838: ([kernel.kallsyms]) syscall_exit_to_user_mode
+ uname 30805 [000] 24001.058784838: ([kernel.kallsyms]) syscall_exit_work
+ uname 30805 [000] 24001.058784838: ([kernel.kallsyms]) perf_syscall_exit
+ uname 30805 [000] 24001.058784838: ([kernel.kallsyms]) debug_smp_processor_id
+ uname 30805 [000] 24001.058785046: ([kernel.kallsyms]) perf_trace_buf_alloc
+ uname 30805 [000] 24001.058785046: ([kernel.kallsyms]) perf_swevent_get_recursion_context
+ uname 30805 [000] 24001.058785046: ([kernel.kallsyms]) debug_smp_processor_id
+ uname 30805 [000] 24001.058785046: ([kernel.kallsyms]) debug_smp_processor_id
+ uname 30805 [000] 24001.058785046: ([kernel.kallsyms]) perf_tp_event
+ uname 30805 [000] 24001.058785046: ([kernel.kallsyms]) perf_trace_buf_update
+ uname 30805 [000] 24001.058785046: ([kernel.kallsyms]) tracing_gen_ctx_irq_test
+ uname 30805 [000] 24001.058785046: ([kernel.kallsyms]) perf_swevent_event
+ uname 30805 [000] 24001.058785046: ([kernel.kallsyms]) __perf_event_account_interrupt
+ uname 30805 [000] 24001.058785046: ([kernel.kallsyms]) __this_cpu_preempt_check
+ uname 30805 [000] 24001.058785046: ([kernel.kallsyms]) perf_event_output_forward
+ uname 30805 [000] 24001.058785046: ([kernel.kallsyms]) perf_event_aux_pause
+ uname 30805 [000] 24001.058785046: ([kernel.kallsyms]) ring_buffer_get
+ uname 30805 [000] 24001.058785046: ([kernel.kallsyms]) __rcu_read_lock
+ uname 30805 [000] 24001.058785046: ([kernel.kallsyms]) __rcu_read_unlock
+ uname 30805 [000] 24001.058785254: ([kernel.kallsyms]) pt_event_stop
+ uname 30805 [000] 24001.058785254: ([kernel.kallsyms]) debug_smp_processor_id
+ uname 30805 [000] 24001.058785254: ([kernel.kallsyms]) debug_smp_processor_id
+ uname 30805 [000] 24001.058785254: ([kernel.kallsyms]) native_write_msr
+ uname 30805 [000] 24001.058785463: ([kernel.kallsyms]) native_write_msr
+ uname 30805 [000] 24001.058785639: 0x0
+
+The example above uses tracepoints, but any kind of sampled event can be used.
+
+For example:
+
+ Tracing between arch_cpu_idle_enter() and arch_cpu_idle_exit() using breakpoint events:
+
+ $ sudo cat /proc/kallsyms | sort | grep ' arch_cpu_idle_enter\| arch_cpu_idle_exit'
+ ffffffffb605bf60 T arch_cpu_idle_enter
+ ffffffffb614d8a0 W arch_cpu_idle_exit
+ $ sudo perf record --kcore -a -e intel_pt/aux-action=start-paused/k -e mem:0xffffffffb605bf60:x/aux-action=resume/ -e mem:0xffffffffb614d8a0:x/aux-action=pause/ -- sleep 1
+ [ perf record: Woken up 1 times to write data ]
+ [ perf record: Captured and wrote 1.387 MB perf.data ]
+
+ Tracing __alloc_pages() using kprobes:
+
+ $ sudo perf probe --add '__alloc_pages order'
+ Added new event: probe:__alloc_pages (on __alloc_pages with order)
+ $ sudo perf probe --add __alloc_pages%return
+ Added new event: probe:__alloc_pages__return (on __alloc_pages%return)
+ $ sudo perf record --kcore -aR -e intel_pt/aux-action=start-paused/k -e probe:__alloc_pages/aux-action=resume/ -e probe:__alloc_pages__return/aux-action=pause/ -- sleep 1
+ [ perf record: Woken up 1 times to write data ]
+ [ perf record: Captured and wrote 1.490 MB perf.data ]
+
+ Tracing starting at main() using a uprobe event:
+
+ $ sudo perf probe -x /usr/bin/uname main
+ Added new event: probe_uname:main (on main in /usr/bin/uname)
+ $ sudo perf record -e intel_pt/-aux-action=start-paused/u -e probe_uname:main/aux-action=resume/ -- uname
+ Linux
+ [ perf record: Woken up 1 times to write data ]
+ [ perf record: Captured and wrote 0.031 MB perf.data ]
+
+ Tracing occasionally using cycles events with different periods:
+
+ $ perf record --kcore -a -m,64M -e intel_pt/aux-action=start-paused/k -e cycles/aux-action=pause,period=1000000/Pk -e cycles/aux-action=resume,period=10500000/Pk -- firefox
+ [ perf record: Woken up 19 times to write data ]
+ [ perf record: Captured and wrote 16.561 MB perf.data ]
+
+
EXAMPLE
-------
--
2.43.0
^ permalink raw reply related [flat|nested] 13+ messages in thread* [PATCH V16 7/7] perf intel-pt: Add a test for pause / resume
2024-12-16 7:02 [PATCH V16 0/7] perf/core: Add ability for an event to "pause" or "resume" AUX area tracing Adrian Hunter
` (5 preceding siblings ...)
2024-12-16 7:02 ` [PATCH V16 6/7] perf intel-pt: Add documentation for pause / resume Adrian Hunter
@ 2024-12-16 7:02 ` Adrian Hunter
2024-12-21 17:10 ` Ian Rogers
6 siblings, 1 reply; 13+ messages in thread
From: Adrian Hunter @ 2024-12-16 7:02 UTC (permalink / raw)
To: Arnaldo Carvalho de Melo, Namhyung Kim
Cc: Jiri Olsa, Ian Rogers, Kan Liang, Leo Yan, linux-kernel,
linux-perf-users
Add a simple sub-test to the "Miscellaneous Intel PT testing" test to
check pause / resume.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
---
tools/perf/tests/shell/test_intel_pt.sh | 28 +++++++++++++++++++++++++
1 file changed, 28 insertions(+)
diff --git a/tools/perf/tests/shell/test_intel_pt.sh b/tools/perf/tests/shell/test_intel_pt.sh
index e6f0070975f6..f3a9a040bacc 100755
--- a/tools/perf/tests/shell/test_intel_pt.sh
+++ b/tools/perf/tests/shell/test_intel_pt.sh
@@ -644,6 +644,33 @@ test_pipe()
return 0
}
+test_pause_resume()
+{
+ echo "--- Test with pause / resume ---"
+ if ! perf_record_no_decode -o "${perfdatafile}" -e intel_pt/aux-action=start-paused/u uname ; then
+ echo "SKIP: pause / resume is not supported"
+ return 2
+ fi
+ if ! perf_record_no_bpf -o "${perfdatafile}" \
+ -e intel_pt/aux-action=start-paused/u \
+ -e instructions/period=50000,aux-action=resume,name=Resume/u \
+ -e instructions/period=100000,aux-action=pause,name=Pause/u uname ; then
+ echo "perf record with pause / resume failed"
+ return 1
+ fi
+ if ! perf script -i "${perfdatafile}" --itrace=b -Fperiod,event | \
+ awk 'BEGIN {paused=1;branches=0}
+ /Resume/ {paused=0}
+ /branches/ {if (paused) exit 1;branches=1}
+ /Pause/ {paused=1}
+ END {if (!branches) exit 1}' ; then
+ echo "perf record with pause / resume failed"
+ return 1
+ fi
+ echo OK
+ return 0
+}
+
count_result()
{
if [ "$1" -eq 2 ] ; then
@@ -672,6 +699,7 @@ test_power_event || ret=$? ; count_result $ret ; ret=0
test_no_tnt || ret=$? ; count_result $ret ; ret=0
test_event_trace || ret=$? ; count_result $ret ; ret=0
test_pipe || ret=$? ; count_result $ret ; ret=0
+test_pause_resume || ret=$? ; count_result $ret ; ret=0
cleanup
--
2.43.0
^ permalink raw reply related [flat|nested] 13+ messages in thread* Re: [PATCH V16 7/7] perf intel-pt: Add a test for pause / resume
2024-12-16 7:02 ` [PATCH V16 7/7] perf intel-pt: Add a test " Adrian Hunter
@ 2024-12-21 17:10 ` Ian Rogers
2024-12-21 19:30 ` Adrian Hunter
0 siblings, 1 reply; 13+ messages in thread
From: Ian Rogers @ 2024-12-21 17:10 UTC (permalink / raw)
To: Adrian Hunter
Cc: Arnaldo Carvalho de Melo, Namhyung Kim, Jiri Olsa, Kan Liang,
Leo Yan, linux-kernel, linux-perf-users
On Sun, Dec 15, 2024 at 11:03 PM Adrian Hunter <adrian.hunter@intel.com> wrote:
>
> Add a simple sub-test to the "Miscellaneous Intel PT testing" test to
> check pause / resume.
>
> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
> Acked-by: Ian Rogers <irogers@google.com>
> Reviewed-by: Andi Kleen <ak@linux.intel.com>
> ---
> tools/perf/tests/shell/test_intel_pt.sh | 28 +++++++++++++++++++++++++
> 1 file changed, 28 insertions(+)
>
> diff --git a/tools/perf/tests/shell/test_intel_pt.sh b/tools/perf/tests/shell/test_intel_pt.sh
> index e6f0070975f6..f3a9a040bacc 100755
> --- a/tools/perf/tests/shell/test_intel_pt.sh
> +++ b/tools/perf/tests/shell/test_intel_pt.sh
> @@ -644,6 +644,33 @@ test_pipe()
> return 0
> }
>
> +test_pause_resume()
> +{
> + echo "--- Test with pause / resume ---"
> + if ! perf_record_no_decode -o "${perfdatafile}" -e intel_pt/aux-action=start-paused/u uname ; then
> + echo "SKIP: pause / resume is not supported"
> + return 2
> + fi
> + if ! perf_record_no_bpf -o "${perfdatafile}" \
> + -e intel_pt/aux-action=start-paused/u \
> + -e instructions/period=50000,aux-action=resume,name=Resume/u \
> + -e instructions/period=100000,aux-action=pause,name=Pause/u uname ; then
> + echo "perf record with pause / resume failed"
> + return 1
> + fi
> + if ! perf script -i "${perfdatafile}" --itrace=b -Fperiod,event | \
> + awk 'BEGIN {paused=1;branches=0}
> + /Resume/ {paused=0}
> + /branches/ {if (paused) exit 1;branches=1}
> + /Pause/ {paused=1}
> + END {if (!branches) exit 1}' ; then
> + echo "perf record with pause / resume failed"
> + return 1
> + fi
> + echo OK
Hi,
this new test is now constantly making "Miscellaneous Intel PT testing" fail:
```
...
--- Test with pause / resume ---
Error:
Failure to open event 'intel_pt/aux-action=start-paused/u' on PMU
'intel_pt' which will be removed.
The 'aux_action' feature is not supported, update the kernel.
Linux
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.003 MB
/tmp/perf-test-intel-pt-sh.Hs8jcq0ADc/test-perf.data ]
Error:
Failure to open event 'intel_pt/aux-action=start-paused/u' on PMU
'intel_pt' which will be removed.
The 'aux_action' feature is not supported, update the kernel.
Error:
Failure to open event 'Resume' on PMU 'cpu' which will be removed.
The 'aux_action' feature is not supported, update the kernel.
Error:
Failure to open event 'Pause' on PMU 'cpu' which will be removed.
The 'aux_action' feature is not supported, update the kernel.
Linux
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.005 MB
/tmp/perf-test-intel-pt-sh.Hs8jcq0ADc/test-perf.data ]
perf record with pause / resume failed
--- Cleaning up ---
...
```
Should the fail be turned into a skip for missing kernel support?
Thanks,
Ian
> + return 0
> +}
> +
> count_result()
> {
> if [ "$1" -eq 2 ] ; then
> @@ -672,6 +699,7 @@ test_power_event || ret=$? ; count_result $ret ; ret=0
> test_no_tnt || ret=$? ; count_result $ret ; ret=0
> test_event_trace || ret=$? ; count_result $ret ; ret=0
> test_pipe || ret=$? ; count_result $ret ; ret=0
> +test_pause_resume || ret=$? ; count_result $ret ; ret=0
>
> cleanup
>
> --
> 2.43.0
>
^ permalink raw reply [flat|nested] 13+ messages in thread* Re: [PATCH V16 7/7] perf intel-pt: Add a test for pause / resume
2024-12-21 17:10 ` Ian Rogers
@ 2024-12-21 19:30 ` Adrian Hunter
2024-12-22 16:54 ` Ian Rogers
0 siblings, 1 reply; 13+ messages in thread
From: Adrian Hunter @ 2024-12-21 19:30 UTC (permalink / raw)
To: Ian Rogers
Cc: Arnaldo Carvalho de Melo, Namhyung Kim, Jiri Olsa, Kan Liang,
Leo Yan, linux-kernel, linux-perf-users
On 21/12/24 19:10, Ian Rogers wrote:
> On Sun, Dec 15, 2024 at 11:03 PM Adrian Hunter <adrian.hunter@intel.com> wrote:
>>
>> Add a simple sub-test to the "Miscellaneous Intel PT testing" test to
>> check pause / resume.
>>
>> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
>> Acked-by: Ian Rogers <irogers@google.com>
>> Reviewed-by: Andi Kleen <ak@linux.intel.com>
>> ---
>> tools/perf/tests/shell/test_intel_pt.sh | 28 +++++++++++++++++++++++++
>> 1 file changed, 28 insertions(+)
>>
>> diff --git a/tools/perf/tests/shell/test_intel_pt.sh b/tools/perf/tests/shell/test_intel_pt.sh
>> index e6f0070975f6..f3a9a040bacc 100755
>> --- a/tools/perf/tests/shell/test_intel_pt.sh
>> +++ b/tools/perf/tests/shell/test_intel_pt.sh
>> @@ -644,6 +644,33 @@ test_pipe()
>> return 0
>> }
>>
>> +test_pause_resume()
>> +{
>> + echo "--- Test with pause / resume ---"
>> + if ! perf_record_no_decode -o "${perfdatafile}" -e intel_pt/aux-action=start-paused/u uname ; then
>> + echo "SKIP: pause / resume is not supported"
>> + return 2
>> + fi
>> + if ! perf_record_no_bpf -o "${perfdatafile}" \
>> + -e intel_pt/aux-action=start-paused/u \
>> + -e instructions/period=50000,aux-action=resume,name=Resume/u \
>> + -e instructions/period=100000,aux-action=pause,name=Pause/u uname ; then
>> + echo "perf record with pause / resume failed"
>> + return 1
>> + fi
>> + if ! perf script -i "${perfdatafile}" --itrace=b -Fperiod,event | \
>> + awk 'BEGIN {paused=1;branches=0}
>> + /Resume/ {paused=0}
>> + /branches/ {if (paused) exit 1;branches=1}
>> + /Pause/ {paused=1}
>> + END {if (!branches) exit 1}' ; then
>> + echo "perf record with pause / resume failed"
>> + return 1
>> + fi
>> + echo OK
>
> Hi,
>
> this new test is now constantly making "Miscellaneous Intel PT testing" fail:
>
> ```
> ...
> --- Test with pause / resume ---
> Error:
> Failure to open event 'intel_pt/aux-action=start-paused/u' on PMU
> 'intel_pt' which will be removed.
> The 'aux_action' feature is not supported, update the kernel.
> Linux
> [ perf record: Woken up 1 times to write data ]
> [ perf record: Captured and wrote 0.003 MB
> /tmp/perf-test-intel-pt-sh.Hs8jcq0ADc/test-perf.data ]
> Error:
> Failure to open event 'intel_pt/aux-action=start-paused/u' on PMU
> 'intel_pt' which will be removed.
> The 'aux_action' feature is not supported, update the kernel.
> Error:
> Failure to open event 'Resume' on PMU 'cpu' which will be removed.
> The 'aux_action' feature is not supported, update the kernel.
> Error:
> Failure to open event 'Pause' on PMU 'cpu' which will be removed.
> The 'aux_action' feature is not supported, update the kernel.
> Linux
> [ perf record: Woken up 1 times to write data ]
> [ perf record: Captured and wrote 0.005 MB
> /tmp/perf-test-intel-pt-sh.Hs8jcq0ADc/test-perf.data ]
> perf record with pause / resume failed
> --- Cleaning up ---
> ...
> ```
>
> Should the fail be turned into a skip for missing kernel support?
Seems to skip for me with perf-tools-next:
--- Test with pause / resume ---
Error:
The 'aux_action' feature is not supported, update the kernel.
SKIP: pause / resume is not supported
perf version 6.13.rc2.g39c2547579aa
>
> Thanks,
> Ian
>
>> + return 0
>> +}
>> +
>> count_result()
>> {
>> if [ "$1" -eq 2 ] ; then
>> @@ -672,6 +699,7 @@ test_power_event || ret=$? ; count_result $ret ; ret=0
>> test_no_tnt || ret=$? ; count_result $ret ; ret=0
>> test_event_trace || ret=$? ; count_result $ret ; ret=0
>> test_pipe || ret=$? ; count_result $ret ; ret=0
>> +test_pause_resume || ret=$? ; count_result $ret ; ret=0
>>
>> cleanup
>>
>> --
>> 2.43.0
>>
^ permalink raw reply [flat|nested] 13+ messages in thread* Re: [PATCH V16 7/7] perf intel-pt: Add a test for pause / resume
2024-12-21 19:30 ` Adrian Hunter
@ 2024-12-22 16:54 ` Ian Rogers
2024-12-22 19:17 ` Adrian Hunter
0 siblings, 1 reply; 13+ messages in thread
From: Ian Rogers @ 2024-12-22 16:54 UTC (permalink / raw)
To: Adrian Hunter
Cc: Arnaldo Carvalho de Melo, Namhyung Kim, Jiri Olsa, Kan Liang,
Leo Yan, linux-kernel, linux-perf-users
On Sat, Dec 21, 2024 at 11:30 AM Adrian Hunter <adrian.hunter@intel.com> wrote:
>
> On 21/12/24 19:10, Ian Rogers wrote:
> > On Sun, Dec 15, 2024 at 11:03 PM Adrian Hunter <adrian.hunter@intel.com> wrote:
> >>
> >> Add a simple sub-test to the "Miscellaneous Intel PT testing" test to
> >> check pause / resume.
> >>
> >> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
> >> Acked-by: Ian Rogers <irogers@google.com>
> >> Reviewed-by: Andi Kleen <ak@linux.intel.com>
> >> ---
> >> tools/perf/tests/shell/test_intel_pt.sh | 28 +++++++++++++++++++++++++
> >> 1 file changed, 28 insertions(+)
> >>
> >> diff --git a/tools/perf/tests/shell/test_intel_pt.sh b/tools/perf/tests/shell/test_intel_pt.sh
> >> index e6f0070975f6..f3a9a040bacc 100755
> >> --- a/tools/perf/tests/shell/test_intel_pt.sh
> >> +++ b/tools/perf/tests/shell/test_intel_pt.sh
> >> @@ -644,6 +644,33 @@ test_pipe()
> >> return 0
> >> }
> >>
> >> +test_pause_resume()
> >> +{
> >> + echo "--- Test with pause / resume ---"
> >> + if ! perf_record_no_decode -o "${perfdatafile}" -e intel_pt/aux-action=start-paused/u uname ; then
> >> + echo "SKIP: pause / resume is not supported"
> >> + return 2
> >> + fi
> >> + if ! perf_record_no_bpf -o "${perfdatafile}" \
> >> + -e intel_pt/aux-action=start-paused/u \
> >> + -e instructions/period=50000,aux-action=resume,name=Resume/u \
> >> + -e instructions/period=100000,aux-action=pause,name=Pause/u uname ; then
> >> + echo "perf record with pause / resume failed"
> >> + return 1
> >> + fi
> >> + if ! perf script -i "${perfdatafile}" --itrace=b -Fperiod,event | \
> >> + awk 'BEGIN {paused=1;branches=0}
> >> + /Resume/ {paused=0}
> >> + /branches/ {if (paused) exit 1;branches=1}
> >> + /Pause/ {paused=1}
> >> + END {if (!branches) exit 1}' ; then
> >> + echo "perf record with pause / resume failed"
> >> + return 1
> >> + fi
> >> + echo OK
> >
> > Hi,
> >
> > this new test is now constantly making "Miscellaneous Intel PT testing" fail:
> >
> > ```
> > ...
> > --- Test with pause / resume ---
> > Error:
> > Failure to open event 'intel_pt/aux-action=start-paused/u' on PMU
> > 'intel_pt' which will be removed.
> > The 'aux_action' feature is not supported, update the kernel.
> > Linux
> > [ perf record: Woken up 1 times to write data ]
> > [ perf record: Captured and wrote 0.003 MB
> > /tmp/perf-test-intel-pt-sh.Hs8jcq0ADc/test-perf.data ]
> > Error:
> > Failure to open event 'intel_pt/aux-action=start-paused/u' on PMU
> > 'intel_pt' which will be removed.
> > The 'aux_action' feature is not supported, update the kernel.
> > Error:
> > Failure to open event 'Resume' on PMU 'cpu' which will be removed.
> > The 'aux_action' feature is not supported, update the kernel.
> > Error:
> > Failure to open event 'Pause' on PMU 'cpu' which will be removed.
> > The 'aux_action' feature is not supported, update the kernel.
> > Linux
> > [ perf record: Woken up 1 times to write data ]
> > [ perf record: Captured and wrote 0.005 MB
> > /tmp/perf-test-intel-pt-sh.Hs8jcq0ADc/test-perf.data ]
> > perf record with pause / resume failed
> > --- Cleaning up ---
> > ...
> > ```
> >
> > Should the fail be turned into a skip for missing kernel support?
>
> Seems to skip for me with perf-tools-next:
>
> --- Test with pause / resume ---
> Error:
> The 'aux_action' feature is not supported, update the kernel.
> SKIP: pause / resume is not supported
>
> perf version 6.13.rc2.g39c2547579aa
My mistake, I thought I tested a clean client but I was testing with:
https://lore.kernel.org/lkml/20241221192654.94344-1-irogers@google.com/
The issue there is that intel-pt is opening multiple dummy events in this test:
```
Breakpoint 2, evlist__new () at util/evlist.c:89
89 struct evlist *evlist = zalloc(sizeof(*evlist));
(gdb) n
91 if (evlist != NULL)
(gdb) p evlist->core.nr_entries
$8 = 0
(gdb) p &evlist->core.nr_entries
$9 = (int *) 0x55555618d150
(gdb) watch *$9
Hardware watchpoint 3: *$9
(gdb) c
Continuing.
Hardware watchpoint 3: *$9
Old value = 0
New value = 1
perf_evlist__add (evlist=0x55555618d140, evsel=0x5555561a6910) at evlist.c:112
112 if (evlist->needs_map_propagation)
(gdb) bt
#0 perf_evlist__add (evlist=0x55555618d140, evsel=0x5555561a6910) at
evlist.c:112
#1 0x00005555557c91ba in evlist__add (evlist=0x55555618d140,
entry=0x5555561a6910)
at util/evlist.c:197
#2 0x00005555557c9320 in evlist__splice_list_tail
(evlist=0x55555618d140, list=0x7fffffffbaa8)
at util/evlist.c:218
#3 0x00005555557eb886 in __parse_events (evlist=0x55555618d140,
str=0x7fffffffe5c1 "intel_pt/aux-action=start-paused/u",
pmu_filter=0x0, err=0x7fffffffbb38,
fake_pmu=false, warn_if_reordered=true, fake_tp=false) at
util/parse-events.c:2166
#4 0x00005555557ec4b4 in parse_events_option (opt=0x5555560e5bb0
<__record_options>,
str=0x7fffffffe5c1 "intel_pt/aux-action=start-paused/u", unset=0)
at util/parse-events.c:2352
#5 0x00005555556acede in get_value (p=0x7fffffffbde0,
opt=0x5555560e5bb0 <__record_options>,
flags=1) at parse-options.c:251
#6 0x00005555556ac13f in parse_short_opt (p=0x7fffffffbde0,
options=0x5555560e5bb0 <__record_options>) at parse-options.c:351
#7 0x00005555556aaecb in parse_options_step (ctx=0x7fffffffbde0,
options=0x5555560e5bb0 <__record_options>, usagestr=0x5555560b5bb0
<__record_usage>)
at parse-options.c:539
#8 0x00005555556aa940 in parse_options_subcommand (argc=4, argv=0x7fffffffe310,
options=0x5555560e5bb0 <__record_options>, subcommands=0x0,
usagestr=0x5555560b5bb0 <__record_usage>, flags=2) at parse-options.c:654
#9 0x00005555556ab3d7 in parse_options (argc=4, argv=0x7fffffffe310,
options=0x5555560e5bb0 <__record_options>, usagestr=0x5555560b5bb0
<__record_usage>, flags=2)
at parse-options.c:689
#10 0x00005555555f23dd in cmd_record (argc=4, argv=0x7fffffffe310) at
builtin-record.c:4021
#11 0x000055555569d42f in run_builtin (p=0x5555560f0cb0 <commands+288>, argc=4,
argv=0x7fffffffe310) at perf.c:351
#12 0x000055555569cae3 in handle_internal_command (argc=4,
argv=0x7fffffffe310) at perf.c:404
#13 0x000055555569d2ff in run_argv (argcp=0x7fffffffe15c,
argv=0x7fffffffe150) at perf.c:448
#14 0x000055555569c73f in main (argc=4, argv=0x7fffffffe310) at perf.c:560
(gdb) c
Continuing.
Breakpoint 2, evlist__new () at util/evlist.c:89
89 struct evlist *evlist = zalloc(sizeof(*evlist));
(gdb) bt
#0 evlist__new () at util/evlist.c:89
#1 0x00005555558a8365 in perf_do_probe_api (fn=0x5555558a7e50
<perf_probe_context_switch>,
cpu=..., str=0x5555559ba4fb "cycles:u") at util/perf_api_probe.c:22
#2 0x00005555558a7c94 in perf_probe_api (fn=0x5555558a7e50
<perf_probe_context_switch>)
at util/perf_api_probe.c:74
#3 0x00005555558a7e21 in perf_can_record_switch_events () at
util/perf_api_probe.c:124
#4 0x000055555597273e in intel_pt_recording_options
(itr=0x5555561a9100, evlist=0x55555618d140,
opts=0x5555560e7b58 <record+320>) at arch/x86/util/intel-pt.c:793
#5 0x00005555558be64d in auxtrace_record__options
(itr=0x5555561a9100, evlist=0x55555618d140,
opts=0x5555560e7b58 <record+320>) at util/auxtrace.c:619
#6 0x00005555555f2da3 in cmd_record (argc=1, argv=0x7fffffffe310) at
builtin-record.c:4226
#7 0x000055555569d42f in run_builtin (p=0x5555560f0cb0 <commands+288>, argc=4,
argv=0x7fffffffe310) at perf.c:351
#8 0x000055555569cae3 in handle_internal_command (argc=4,
argv=0x7fffffffe310) at perf.c:404
#9 0x000055555569d2ff in run_argv (argcp=0x7fffffffe15c,
argv=0x7fffffffe150) at perf.c:448
#10 0x000055555569c73f in main (argc=4, argv=0x7fffffffe310) at perf.c:560
(gdb) c
Continuing.
Hardware watchpoint 3: *$9
Old value = 1
New value = 2
perf_evlist__add (evlist=0x55555618d140, evsel=0x5555561a6c10) at evlist.c:112
112 if (evlist->needs_map_propagation)
(gdb) bt
#0 perf_evlist__add (evlist=0x55555618d140, evsel=0x5555561a6c10) at
evlist.c:112
#1 0x00005555557c91ba in evlist__add (evlist=0x55555618d140,
entry=0x5555561a6c10)
at util/evlist.c:197
#2 0x00005555557c980a in evlist__add_aux_dummy
(evlist=0x55555618d140, system_wide=true)
at util/evlist.c:299
#3 0x0000555555974297 in evlist__add_dummy_on_all_cpus (evlist=0x55555618d140)
at arch/x86/util/../../../util/evlist.h:111
#4 0x00005555559727ae in intel_pt_recording_options
(itr=0x5555561a9100, evlist=0x55555618d140,
opts=0x5555560e7b58 <record+320>) at arch/x86/util/intel-pt.c:800
#5 0x00005555558be64d in auxtrace_record__options
(itr=0x5555561a9100, evlist=0x55555618d140,
opts=0x5555560e7b58 <record+320>) at util/auxtrace.c:619
#6 0x00005555555f2da3 in cmd_record (argc=1, argv=0x7fffffffe310) at
builtin-record.c:4226
#7 0x000055555569d42f in run_builtin (p=0x5555560f0cb0 <commands+288>, argc=4,
argv=0x7fffffffe310) at perf.c:351
#8 0x000055555569cae3 in handle_internal_command (argc=4,
argv=0x7fffffffe310) at perf.c:404
#9 0x000055555569d2ff in run_argv (argcp=0x7fffffffe15c,
argv=0x7fffffffe150) at perf.c:448
#10 0x000055555569c73f in main (argc=4, argv=0x7fffffffe310) at perf.c:560
(gdb) c
Continuing.
Hardware watchpoint 3: *$9
Old value = 2
New value = 3
perf_evlist__add (evlist=0x55555618d140, evsel=0x5555561a6ef0) at evlist.c:112
112 if (evlist->needs_map_propagation)
(gdb) bt
#0 perf_evlist__add (evlist=0x55555618d140, evsel=0x5555561a6ef0) at
evlist.c:112
#1 0x00005555557c91ba in evlist__add (evlist=0x55555618d140,
entry=0x5555561a6ef0)
at util/evlist.c:197
#2 0x00005555557c980a in evlist__add_aux_dummy
(evlist=0x55555618d140, system_wide=false)
at util/evlist.c:299
#3 0x00005555559729f8 in intel_pt_recording_options
(itr=0x5555561a9100, evlist=0x55555618d140,
opts=0x5555560e7b58 <record+320>) at arch/x86/util/intel-pt.c:865
#4 0x00005555558be64d in auxtrace_record__options
(itr=0x5555561a9100, evlist=0x55555618d140,
opts=0x5555560e7b58 <record+320>) at util/auxtrace.c:619
#5 0x00005555555f2da3 in cmd_record (argc=1, argv=0x7fffffffe310) at
builtin-record.c:4226
#6 0x000055555569d42f in run_builtin (p=0x5555560f0cb0 <commands+288>, argc=4,
argv=0x7fffffffe310) at perf.c:351
#7 0x000055555569cae3 in handle_internal_command (argc=4,
argv=0x7fffffffe310) at perf.c:404
#8 0x000055555569d2ff in run_argv (argcp=0x7fffffffe15c,
argv=0x7fffffffe150) at perf.c:448
#9 0x000055555569c73f in main (argc=4, argv=0x7fffffffe310) at perf.c:560
(gdb)
```
That is a dummy event is added in 2 places:
https://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools-next.git/tree/tools/perf/arch/x86/util/intel-pt.c?h=perf-tools-next#n800
https://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools-next.git/tree/tools/perf/arch/x86/util/intel-pt.c?h=perf-tools-next#n865
I'll need to update my patch set for things outside of record adding
dummy events, but I'm curious if the intel-pt code could share a
single dummy evsel?
Thanks,
Ian
^ permalink raw reply [flat|nested] 13+ messages in thread* Re: [PATCH V16 7/7] perf intel-pt: Add a test for pause / resume
2024-12-22 16:54 ` Ian Rogers
@ 2024-12-22 19:17 ` Adrian Hunter
2024-12-23 20:26 ` Ian Rogers
0 siblings, 1 reply; 13+ messages in thread
From: Adrian Hunter @ 2024-12-22 19:17 UTC (permalink / raw)
To: Ian Rogers
Cc: Arnaldo Carvalho de Melo, Namhyung Kim, Jiri Olsa, Kan Liang,
Leo Yan, linux-kernel, linux-perf-users
On 22/12/24 18:54, Ian Rogers wrote:
> On Sat, Dec 21, 2024 at 11:30 AM Adrian Hunter <adrian.hunter@intel.com> wrote:
>>
>> On 21/12/24 19:10, Ian Rogers wrote:
>>> On Sun, Dec 15, 2024 at 11:03 PM Adrian Hunter <adrian.hunter@intel.com> wrote:
>>>>
>>>> Add a simple sub-test to the "Miscellaneous Intel PT testing" test to
>>>> check pause / resume.
>>>>
>>>> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
>>>> Acked-by: Ian Rogers <irogers@google.com>
>>>> Reviewed-by: Andi Kleen <ak@linux.intel.com>
>>>> ---
>>>> tools/perf/tests/shell/test_intel_pt.sh | 28 +++++++++++++++++++++++++
>>>> 1 file changed, 28 insertions(+)
>>>>
>>>> diff --git a/tools/perf/tests/shell/test_intel_pt.sh b/tools/perf/tests/shell/test_intel_pt.sh
>>>> index e6f0070975f6..f3a9a040bacc 100755
>>>> --- a/tools/perf/tests/shell/test_intel_pt.sh
>>>> +++ b/tools/perf/tests/shell/test_intel_pt.sh
>>>> @@ -644,6 +644,33 @@ test_pipe()
>>>> return 0
>>>> }
>>>>
>>>> +test_pause_resume()
>>>> +{
>>>> + echo "--- Test with pause / resume ---"
>>>> + if ! perf_record_no_decode -o "${perfdatafile}" -e intel_pt/aux-action=start-paused/u uname ; then
>>>> + echo "SKIP: pause / resume is not supported"
>>>> + return 2
>>>> + fi
>>>> + if ! perf_record_no_bpf -o "${perfdatafile}" \
>>>> + -e intel_pt/aux-action=start-paused/u \
>>>> + -e instructions/period=50000,aux-action=resume,name=Resume/u \
>>>> + -e instructions/period=100000,aux-action=pause,name=Pause/u uname ; then
>>>> + echo "perf record with pause / resume failed"
>>>> + return 1
>>>> + fi
>>>> + if ! perf script -i "${perfdatafile}" --itrace=b -Fperiod,event | \
>>>> + awk 'BEGIN {paused=1;branches=0}
>>>> + /Resume/ {paused=0}
>>>> + /branches/ {if (paused) exit 1;branches=1}
>>>> + /Pause/ {paused=1}
>>>> + END {if (!branches) exit 1}' ; then
>>>> + echo "perf record with pause / resume failed"
>>>> + return 1
>>>> + fi
>>>> + echo OK
>>>
>>> Hi,
>>>
>>> this new test is now constantly making "Miscellaneous Intel PT testing" fail:
>>>
>>> ```
>>> ...
>>> --- Test with pause / resume ---
>>> Error:
>>> Failure to open event 'intel_pt/aux-action=start-paused/u' on PMU
>>> 'intel_pt' which will be removed.
>>> The 'aux_action' feature is not supported, update the kernel.
>>> Linux
>>> [ perf record: Woken up 1 times to write data ]
>>> [ perf record: Captured and wrote 0.003 MB
>>> /tmp/perf-test-intel-pt-sh.Hs8jcq0ADc/test-perf.data ]
>>> Error:
>>> Failure to open event 'intel_pt/aux-action=start-paused/u' on PMU
>>> 'intel_pt' which will be removed.
>>> The 'aux_action' feature is not supported, update the kernel.
>>> Error:
>>> Failure to open event 'Resume' on PMU 'cpu' which will be removed.
>>> The 'aux_action' feature is not supported, update the kernel.
>>> Error:
>>> Failure to open event 'Pause' on PMU 'cpu' which will be removed.
>>> The 'aux_action' feature is not supported, update the kernel.
>>> Linux
>>> [ perf record: Woken up 1 times to write data ]
>>> [ perf record: Captured and wrote 0.005 MB
>>> /tmp/perf-test-intel-pt-sh.Hs8jcq0ADc/test-perf.data ]
>>> perf record with pause / resume failed
>>> --- Cleaning up ---
>>> ...
>>> ```
>>>
>>> Should the fail be turned into a skip for missing kernel support?
>>
>> Seems to skip for me with perf-tools-next:
>>
>> --- Test with pause / resume ---
>> Error:
>> The 'aux_action' feature is not supported, update the kernel.
>> SKIP: pause / resume is not supported
>>
>> perf version 6.13.rc2.g39c2547579aa
>
> My mistake, I thought I tested a clean client but I was testing with:
> https://lore.kernel.org/lkml/20241221192654.94344-1-irogers@google.com/
> The issue there is that intel-pt is opening multiple dummy events in this test:
>
> That is a dummy event is added in 2 places:
> https://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools-next.git/tree/tools/perf/arch/x86/util/intel-pt.c?h=perf-tools-next#n800
> https://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools-next.git/tree/tools/perf/arch/x86/util/intel-pt.c?h=perf-tools-next#n865
>
> I'll need to update my patch set for things outside of record adding
> dummy events, but I'm curious if the intel-pt code could share a
> single dummy evsel?
I doubt it. There are cases where capturing auxiliary events
like text_poke or context_switch want to be system-wide while
the workload task events (comm, task, mmap2) are not.
^ permalink raw reply [flat|nested] 13+ messages in thread* Re: [PATCH V16 7/7] perf intel-pt: Add a test for pause / resume
2024-12-22 19:17 ` Adrian Hunter
@ 2024-12-23 20:26 ` Ian Rogers
0 siblings, 0 replies; 13+ messages in thread
From: Ian Rogers @ 2024-12-23 20:26 UTC (permalink / raw)
To: Adrian Hunter
Cc: Arnaldo Carvalho de Melo, Namhyung Kim, Jiri Olsa, Kan Liang,
Leo Yan, linux-kernel, linux-perf-users
On Sun, Dec 22, 2024 at 11:17 AM Adrian Hunter <adrian.hunter@intel.com> wrote:
>
> On 22/12/24 18:54, Ian Rogers wrote:
> > On Sat, Dec 21, 2024 at 11:30 AM Adrian Hunter <adrian.hunter@intel.com> wrote:
> >>
> >> On 21/12/24 19:10, Ian Rogers wrote:
> >>> On Sun, Dec 15, 2024 at 11:03 PM Adrian Hunter <adrian.hunter@intel.com> wrote:
> >>>>
> >>>> Add a simple sub-test to the "Miscellaneous Intel PT testing" test to
> >>>> check pause / resume.
> >>>>
> >>>> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
> >>>> Acked-by: Ian Rogers <irogers@google.com>
> >>>> Reviewed-by: Andi Kleen <ak@linux.intel.com>
> >>>> ---
> >>>> tools/perf/tests/shell/test_intel_pt.sh | 28 +++++++++++++++++++++++++
> >>>> 1 file changed, 28 insertions(+)
> >>>>
> >>>> diff --git a/tools/perf/tests/shell/test_intel_pt.sh b/tools/perf/tests/shell/test_intel_pt.sh
> >>>> index e6f0070975f6..f3a9a040bacc 100755
> >>>> --- a/tools/perf/tests/shell/test_intel_pt.sh
> >>>> +++ b/tools/perf/tests/shell/test_intel_pt.sh
> >>>> @@ -644,6 +644,33 @@ test_pipe()
> >>>> return 0
> >>>> }
> >>>>
> >>>> +test_pause_resume()
> >>>> +{
> >>>> + echo "--- Test with pause / resume ---"
> >>>> + if ! perf_record_no_decode -o "${perfdatafile}" -e intel_pt/aux-action=start-paused/u uname ; then
> >>>> + echo "SKIP: pause / resume is not supported"
> >>>> + return 2
> >>>> + fi
> >>>> + if ! perf_record_no_bpf -o "${perfdatafile}" \
> >>>> + -e intel_pt/aux-action=start-paused/u \
> >>>> + -e instructions/period=50000,aux-action=resume,name=Resume/u \
> >>>> + -e instructions/period=100000,aux-action=pause,name=Pause/u uname ; then
> >>>> + echo "perf record with pause / resume failed"
> >>>> + return 1
> >>>> + fi
> >>>> + if ! perf script -i "${perfdatafile}" --itrace=b -Fperiod,event | \
> >>>> + awk 'BEGIN {paused=1;branches=0}
> >>>> + /Resume/ {paused=0}
> >>>> + /branches/ {if (paused) exit 1;branches=1}
> >>>> + /Pause/ {paused=1}
> >>>> + END {if (!branches) exit 1}' ; then
> >>>> + echo "perf record with pause / resume failed"
> >>>> + return 1
> >>>> + fi
> >>>> + echo OK
> >>>
> >>> Hi,
> >>>
> >>> this new test is now constantly making "Miscellaneous Intel PT testing" fail:
> >>>
> >>> ```
> >>> ...
> >>> --- Test with pause / resume ---
> >>> Error:
> >>> Failure to open event 'intel_pt/aux-action=start-paused/u' on PMU
> >>> 'intel_pt' which will be removed.
> >>> The 'aux_action' feature is not supported, update the kernel.
> >>> Linux
> >>> [ perf record: Woken up 1 times to write data ]
> >>> [ perf record: Captured and wrote 0.003 MB
> >>> /tmp/perf-test-intel-pt-sh.Hs8jcq0ADc/test-perf.data ]
> >>> Error:
> >>> Failure to open event 'intel_pt/aux-action=start-paused/u' on PMU
> >>> 'intel_pt' which will be removed.
> >>> The 'aux_action' feature is not supported, update the kernel.
> >>> Error:
> >>> Failure to open event 'Resume' on PMU 'cpu' which will be removed.
> >>> The 'aux_action' feature is not supported, update the kernel.
> >>> Error:
> >>> Failure to open event 'Pause' on PMU 'cpu' which will be removed.
> >>> The 'aux_action' feature is not supported, update the kernel.
> >>> Linux
> >>> [ perf record: Woken up 1 times to write data ]
> >>> [ perf record: Captured and wrote 0.005 MB
> >>> /tmp/perf-test-intel-pt-sh.Hs8jcq0ADc/test-perf.data ]
> >>> perf record with pause / resume failed
> >>> --- Cleaning up ---
> >>> ...
> >>> ```
> >>>
> >>> Should the fail be turned into a skip for missing kernel support?
> >>
> >> Seems to skip for me with perf-tools-next:
> >>
> >> --- Test with pause / resume ---
> >> Error:
> >> The 'aux_action' feature is not supported, update the kernel.
> >> SKIP: pause / resume is not supported
> >>
> >> perf version 6.13.rc2.g39c2547579aa
> >
> > My mistake, I thought I tested a clean client but I was testing with:
> > https://lore.kernel.org/lkml/20241221192654.94344-1-irogers@google.com/
> > The issue there is that intel-pt is opening multiple dummy events in this test:
>
> >
> > That is a dummy event is added in 2 places:
> > https://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools-next.git/tree/tools/perf/arch/x86/util/intel-pt.c?h=perf-tools-next#n800
> > https://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools-next.git/tree/tools/perf/arch/x86/util/intel-pt.c?h=perf-tools-next#n865
> >
> > I'll need to update my patch set for things outside of record adding
> > dummy events, but I'm curious if the intel-pt code could share a
> > single dummy evsel?
>
> I doubt it. There are cases where capturing auxiliary events
> like text_poke or context_switch want to be system-wide while
> the workload task events (comm, task, mmap2) are not.
Thanks, I'll rework the dummy event detection because of this. I'm a
little concerned about APIs like `evlist__findnew_tracking_event`, nit
that we're inconsistent on naming (dummy vs tracking vs sideband),
perhaps we need an enum to capture the different
dummy/tracking/sideband event kinds for APIs like this, given the
expectation that there can be >1. Something I hope to do for uncore
evsels is to move the multiple PMUs into the evsel itself. My hope is
that will help with `perf stat` aggregation logic and the like, as
well as simplifying event sorting. Perhaps the evsel for a
dummy/tracking/sideband event can cover >1 use-case to reduce the
evlist's evsels.
Thanks,
Ian
^ permalink raw reply [flat|nested] 13+ messages in thread