The tool will now default to this new mode if the user specifies a
sampling group when not in system-wide mode, and when --no-inherit
is not specified.
This change updates evsel to allow the combination of inherit
and PERF_SAMPLE_READ.
A fallback is implemented for kernel versions where this feature is not
supported.
Signed-off-by: Ben Gainey <ben.gainey@arm.com>
---
tools/perf/tests/attr/README | 2 +
.../tests/attr/test-record-group-sampling | 39 ------------
.../tests/attr/test-record-group-sampling1 | 50 ++++++++++++++++
.../tests/attr/test-record-group-sampling2 | 60 +++++++++++++++++++
tools/perf/tests/attr/test-record-group2 | 9 +--
tools/perf/util/evsel.c | 19 +++++-
tools/perf/util/evsel.h | 1 +
7 files changed, 135 insertions(+), 45 deletions(-)
delete mode 100644 tools/perf/tests/attr/test-record-group-sampling
create mode 100644 tools/perf/tests/attr/test-record-group-sampling1
create mode 100644 tools/perf/tests/attr/test-record-group-sampling2
diff --git a/tools/perf/tests/attr/README b/tools/perf/tests/attr/README
index 4066fec7180a8..67c4ca76b85d5 100644
--- a/tools/perf/tests/attr/README
+++ b/tools/perf/tests/attr/README
@@ -51,6 +51,8 @@ Following tests are defined (with perf commands):
perf record --call-graph fp kill (test-record-graph-fp-aarch64)
perf record -e '{cycles,instructions}' kill (test-record-group1)
perf record -e '{cycles/period=1/,instructions/period=2/}:S' kill (test-record-group2)
+ perf record -e '{cycles,cache-misses}:S' kill (test-record-group-sampling1)
+ perf record -c 10000 -e '{cycles,cache-misses}:S' kill (test-record-group-sampling2)
perf record -D kill (test-record-no-delay)
perf record -i kill (test-record-no-inherit)
perf record -n kill (test-record-no-samples)
diff --git a/tools/perf/tests/attr/test-record-group-sampling b/tools/perf/tests/attr/test-record-group-sampling
deleted file mode 100644
index 97e7e64a38f07..0000000000000
--- a/tools/perf/tests/attr/test-record-group-sampling
+++ /dev/null
@@ -1,39 +0,0 @@
-[config]
-command = record
-args = --no-bpf-event -e '{cycles,cache-misses}:S' kill >/dev/null 2>&1
-ret = 1
-
-[event-1:base-record]
-fd=1
-group_fd=-1
-sample_type=343
-read_format=12|28
-inherit=0
-
-[event-2:base-record]
-fd=2
-group_fd=1
-
-# cache-misses
-type=0
-config=3
-
-# default | PERF_SAMPLE_READ
-sample_type=343
-
-# PERF_FORMAT_ID | PERF_FORMAT_GROUP | PERF_FORMAT_LOST
-read_format=12|28
-task=0
-mmap=0
-comm=0
-enable_on_exec=0
-disabled=0
-
-# inherit is disabled for group sampling
-inherit=0
-
-# sampling disabled
-sample_freq=0
-sample_period=0
-freq=0
-write_backward=0
diff --git a/tools/perf/tests/attr/test-record-group-sampling1 b/tools/perf/tests/attr/test-record-group-sampling1
new file mode 100644
index 0000000000000..9b87306266329
--- /dev/null
+++ b/tools/perf/tests/attr/test-record-group-sampling1
@@ -0,0 +1,50 @@
+[config]
+command = record
+args = --no-bpf-event -e '{cycles,cache-misses}:S' kill >/dev/null 2>&1
+ret = 1
+
+[event-1:base-record]
+fd=1
+group_fd=-1
+
+# cycles
+type=0
+config=0
+
+# default | PERF_SAMPLE_READ
+sample_type=343
+
+# PERF_FORMAT_ID | PERF_FORMAT_GROUP | PERF_FORMAT_LOST | PERF_FORMAT_TOTAL_TIME_ENABLED | PERF_FORMAT_TOTAL_TIME_RUNNING
+read_format=28|31
+task=1
+mmap=1
+comm=1
+enable_on_exec=1
+disabled=1
+
+# inherit is enabled for group sampling
+inherit=1
+
+[event-2:base-record]
+fd=2
+group_fd=1
+
+# cache-misses
+type=0
+config=3
+
+# default | PERF_SAMPLE_READ
+sample_type=343
+
+# PERF_FORMAT_ID | PERF_FORMAT_GROUP | PERF_FORMAT_LOST | PERF_FORMAT_TOTAL_TIME_ENABLED | PERF_FORMAT_TOTAL_TIME_RUNNING
+read_format=28|31
+task=0
+mmap=0
+comm=0
+enable_on_exec=0
+disabled=0
+freq=0
+
+# inherit is enabled for group sampling
+inherit=1
+
diff --git a/tools/perf/tests/attr/test-record-group-sampling2 b/tools/perf/tests/attr/test-record-group-sampling2
new file mode 100644
index 0000000000000..8e29fc13f6668
--- /dev/null
+++ b/tools/perf/tests/attr/test-record-group-sampling2
@@ -0,0 +1,60 @@
+[config]
+command = record
+args = --no-bpf-event -c 10000 -e '{cycles,cache-misses}:S' kill >/dev/null 2>&1
+ret = 1
+
+[event-1:base-record]
+fd=1
+group_fd=-1
+
+# cycles
+type=0
+config=0
+
+# default | PERF_SAMPLE_READ
+sample_type=87
+
+# PERF_FORMAT_ID | PERF_FORMAT_GROUP | PERF_FORMAT_LOST | PERF_FORMAT_TOTAL_TIME_ENABLED | PERF_FORMAT_TOTAL_TIME_RUNNING
+read_format=28|31
+task=1
+mmap=1
+comm=1
+enable_on_exec=1
+disabled=1
+
+# inherit is enabled for group sampling
+inherit=1
+
+# sampling disabled
+sample_freq=0
+sample_period=10000
+freq=0
+write_backward=0
+
+[event-2:base-record]
+fd=2
+group_fd=1
+
+# cache-misses
+type=0
+config=3
+
+# default | PERF_SAMPLE_READ
+sample_type=87
+
+# PERF_FORMAT_ID | PERF_FORMAT_GROUP | PERF_FORMAT_LOST | PERF_FORMAT_TOTAL_TIME_ENABLED | PERF_FORMAT_TOTAL_TIME_RUNNING
+read_format=28|31
+task=0
+mmap=0
+comm=0
+enable_on_exec=0
+disabled=0
+
+# inherit is enabled for group sampling
+inherit=1
+
+# sampling disabled
+sample_freq=0
+sample_period=0
+freq=0
+write_backward=0
diff --git a/tools/perf/tests/attr/test-record-group2 b/tools/perf/tests/attr/test-record-group2
index cebdaa8e64e47..785892a54d9e1 100644
--- a/tools/perf/tests/attr/test-record-group2
+++ b/tools/perf/tests/attr/test-record-group2
@@ -9,8 +9,9 @@ group_fd=-1
config=0|1
sample_period=1234000
sample_type=87
-read_format=12|28
-inherit=0
+read_format=28|31
+disabled=1
+inherit=1
freq=0
[event-2:base-record]
@@ -19,9 +20,9 @@ group_fd=1
config=0|1
sample_period=6789000
sample_type=87
-read_format=12|28
+read_format=28|31
disabled=0
-inherit=0
+inherit=1
mmap=0
comm=0
freq=0
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 3536404e9447b..557d409c53d6c 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1156,7 +1156,15 @@ void evsel__config(struct evsel *evsel, struct record_opts *opts,
*/
if (leader->core.nr_members > 1) {
attr->read_format |= PERF_FORMAT_GROUP;
- attr->inherit = 0;
+ }
+
+ /*
+ * Inherit + SAMPLE_READ requires SAMPLE_TID in the read_format
+ */
+ if (attr->inherit) {
+ evsel__set_sample_bit(evsel, TID);
+ evsel->core.attr.read_format |=
+ PERF_FORMAT_ID;
}
}
@@ -1832,6 +1840,8 @@ static int __evsel__prepare_open(struct evsel *evsel, struct perf_cpu_map *cpus,
static void evsel__disable_missing_features(struct evsel *evsel)
{
+ if (perf_missing_features.inherit_sample_read)
+ evsel->core.attr.inherit = 0;
if (perf_missing_features.branch_counters)
evsel->core.attr.branch_sample_type &= ~PERF_SAMPLE_BRANCH_COUNTERS;
if (perf_missing_features.read_lost)
@@ -1887,7 +1897,12 @@ bool evsel__detect_missing_features(struct evsel *evsel)
* Must probe features in the order they were added to the
* perf_event_attr interface.
*/
- if (!perf_missing_features.branch_counters &&
+ if (!perf_missing_features.inherit_sample_read &&
+ evsel->core.attr.inherit && (evsel->core.attr.sample_type & PERF_SAMPLE_READ)) {
+ perf_missing_features.inherit_sample_read = true;
+ pr_debug2("Using PERF_SAMPLE_READ / :S modifier is not compatible with inherit, falling back to no-inherit.\n");
+ return true;
+ } else if (!perf_missing_features.branch_counters &&
(evsel->core.attr.branch_sample_type & PERF_SAMPLE_BRANCH_COUNTERS)) {
perf_missing_features.branch_counters = true;
pr_debug2("switching off branch counters support\n");
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index 517cff431de20..21b8b7e70e75e 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -192,6 +192,7 @@ struct perf_missing_features {
bool weight_struct;
bool read_lost;
bool branch_counters;
+ bool inherit_sample_read;
};
extern struct perf_missing_features perf_missing_features;
--
2.45.1On Tue, May 21, 2024 at 6:30 AM Ben Gainey <ben.gainey@arm.com> wrote:
>
> The tool will now default to this new mode if the user specifies a
> sampling group when not in system-wide mode, and when --no-inherit
> is not specified.
>
> This change updates evsel to allow the combination of inherit
> and PERF_SAMPLE_READ.
>
> A fallback is implemented for kernel versions where this feature is not
> supported.
But I'm afraid the test would fail on old kernels. Maybe we need to
put it in the selftests.
Thanks,
Namhyung
>
> Signed-off-by: Ben Gainey <ben.gainey@arm.com>
> ---
> tools/perf/tests/attr/README | 2 +
> .../tests/attr/test-record-group-sampling | 39 ------------
> .../tests/attr/test-record-group-sampling1 | 50 ++++++++++++++++
> .../tests/attr/test-record-group-sampling2 | 60 +++++++++++++++++++
> tools/perf/tests/attr/test-record-group2 | 9 +--
> tools/perf/util/evsel.c | 19 +++++-
> tools/perf/util/evsel.h | 1 +
> 7 files changed, 135 insertions(+), 45 deletions(-)
> delete mode 100644 tools/perf/tests/attr/test-record-group-sampling
> create mode 100644 tools/perf/tests/attr/test-record-group-sampling1
> create mode 100644 tools/perf/tests/attr/test-record-group-sampling2
>
> diff --git a/tools/perf/tests/attr/README b/tools/perf/tests/attr/README
> index 4066fec7180a8..67c4ca76b85d5 100644
> --- a/tools/perf/tests/attr/README
> +++ b/tools/perf/tests/attr/README
> @@ -51,6 +51,8 @@ Following tests are defined (with perf commands):
> perf record --call-graph fp kill (test-record-graph-fp-aarch64)
> perf record -e '{cycles,instructions}' kill (test-record-group1)
> perf record -e '{cycles/period=1/,instructions/period=2/}:S' kill (test-record-group2)
> + perf record -e '{cycles,cache-misses}:S' kill (test-record-group-sampling1)
> + perf record -c 10000 -e '{cycles,cache-misses}:S' kill (test-record-group-sampling2)
> perf record -D kill (test-record-no-delay)
> perf record -i kill (test-record-no-inherit)
> perf record -n kill (test-record-no-samples)
> diff --git a/tools/perf/tests/attr/test-record-group-sampling b/tools/perf/tests/attr/test-record-group-sampling
> deleted file mode 100644
> index 97e7e64a38f07..0000000000000
> --- a/tools/perf/tests/attr/test-record-group-sampling
> +++ /dev/null
> @@ -1,39 +0,0 @@
> -[config]
> -command = record
> -args = --no-bpf-event -e '{cycles,cache-misses}:S' kill >/dev/null 2>&1
> -ret = 1
> -
> -[event-1:base-record]
> -fd=1
> -group_fd=-1
> -sample_type=343
> -read_format=12|28
> -inherit=0
> -
> -[event-2:base-record]
> -fd=2
> -group_fd=1
> -
> -# cache-misses
> -type=0
> -config=3
> -
> -# default | PERF_SAMPLE_READ
> -sample_type=343
> -
> -# PERF_FORMAT_ID | PERF_FORMAT_GROUP | PERF_FORMAT_LOST
> -read_format=12|28
> -task=0
> -mmap=0
> -comm=0
> -enable_on_exec=0
> -disabled=0
> -
> -# inherit is disabled for group sampling
> -inherit=0
> -
> -# sampling disabled
> -sample_freq=0
> -sample_period=0
> -freq=0
> -write_backward=0
> diff --git a/tools/perf/tests/attr/test-record-group-sampling1 b/tools/perf/tests/attr/test-record-group-sampling1
> new file mode 100644
> index 0000000000000..9b87306266329
> --- /dev/null
> +++ b/tools/perf/tests/attr/test-record-group-sampling1
> @@ -0,0 +1,50 @@
> +[config]
> +command = record
> +args = --no-bpf-event -e '{cycles,cache-misses}:S' kill >/dev/null 2>&1
> +ret = 1
> +
> +[event-1:base-record]
> +fd=1
> +group_fd=-1
> +
> +# cycles
> +type=0
> +config=0
> +
> +# default | PERF_SAMPLE_READ
> +sample_type=343
> +
> +# PERF_FORMAT_ID | PERF_FORMAT_GROUP | PERF_FORMAT_LOST | PERF_FORMAT_TOTAL_TIME_ENABLED | PERF_FORMAT_TOTAL_TIME_RUNNING
> +read_format=28|31
> +task=1
> +mmap=1
> +comm=1
> +enable_on_exec=1
> +disabled=1
> +
> +# inherit is enabled for group sampling
> +inherit=1
> +
> +[event-2:base-record]
> +fd=2
> +group_fd=1
> +
> +# cache-misses
> +type=0
> +config=3
> +
> +# default | PERF_SAMPLE_READ
> +sample_type=343
> +
> +# PERF_FORMAT_ID | PERF_FORMAT_GROUP | PERF_FORMAT_LOST | PERF_FORMAT_TOTAL_TIME_ENABLED | PERF_FORMAT_TOTAL_TIME_RUNNING
> +read_format=28|31
> +task=0
> +mmap=0
> +comm=0
> +enable_on_exec=0
> +disabled=0
> +freq=0
> +
> +# inherit is enabled for group sampling
> +inherit=1
> +
> diff --git a/tools/perf/tests/attr/test-record-group-sampling2 b/tools/perf/tests/attr/test-record-group-sampling2
> new file mode 100644
> index 0000000000000..8e29fc13f6668
> --- /dev/null
> +++ b/tools/perf/tests/attr/test-record-group-sampling2
> @@ -0,0 +1,60 @@
> +[config]
> +command = record
> +args = --no-bpf-event -c 10000 -e '{cycles,cache-misses}:S' kill >/dev/null 2>&1
> +ret = 1
> +
> +[event-1:base-record]
> +fd=1
> +group_fd=-1
> +
> +# cycles
> +type=0
> +config=0
> +
> +# default | PERF_SAMPLE_READ
> +sample_type=87
> +
> +# PERF_FORMAT_ID | PERF_FORMAT_GROUP | PERF_FORMAT_LOST | PERF_FORMAT_TOTAL_TIME_ENABLED | PERF_FORMAT_TOTAL_TIME_RUNNING
> +read_format=28|31
> +task=1
> +mmap=1
> +comm=1
> +enable_on_exec=1
> +disabled=1
> +
> +# inherit is enabled for group sampling
> +inherit=1
> +
> +# sampling disabled
> +sample_freq=0
> +sample_period=10000
> +freq=0
> +write_backward=0
> +
> +[event-2:base-record]
> +fd=2
> +group_fd=1
> +
> +# cache-misses
> +type=0
> +config=3
> +
> +# default | PERF_SAMPLE_READ
> +sample_type=87
> +
> +# PERF_FORMAT_ID | PERF_FORMAT_GROUP | PERF_FORMAT_LOST | PERF_FORMAT_TOTAL_TIME_ENABLED | PERF_FORMAT_TOTAL_TIME_RUNNING
> +read_format=28|31
> +task=0
> +mmap=0
> +comm=0
> +enable_on_exec=0
> +disabled=0
> +
> +# inherit is enabled for group sampling
> +inherit=1
> +
> +# sampling disabled
> +sample_freq=0
> +sample_period=0
> +freq=0
> +write_backward=0
> diff --git a/tools/perf/tests/attr/test-record-group2 b/tools/perf/tests/attr/test-record-group2
> index cebdaa8e64e47..785892a54d9e1 100644
> --- a/tools/perf/tests/attr/test-record-group2
> +++ b/tools/perf/tests/attr/test-record-group2
> @@ -9,8 +9,9 @@ group_fd=-1
> config=0|1
> sample_period=1234000
> sample_type=87
> -read_format=12|28
> -inherit=0
> +read_format=28|31
> +disabled=1
> +inherit=1
> freq=0
>
> [event-2:base-record]
> @@ -19,9 +20,9 @@ group_fd=1
> config=0|1
> sample_period=6789000
> sample_type=87
> -read_format=12|28
> +read_format=28|31
> disabled=0
> -inherit=0
> +inherit=1
> mmap=0
> comm=0
> freq=0
> diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
> index 3536404e9447b..557d409c53d6c 100644
> --- a/tools/perf/util/evsel.c
> +++ b/tools/perf/util/evsel.c
> @@ -1156,7 +1156,15 @@ void evsel__config(struct evsel *evsel, struct record_opts *opts,
> */
> if (leader->core.nr_members > 1) {
> attr->read_format |= PERF_FORMAT_GROUP;
> - attr->inherit = 0;
> + }
> +
> + /*
> + * Inherit + SAMPLE_READ requires SAMPLE_TID in the read_format
> + */
> + if (attr->inherit) {
> + evsel__set_sample_bit(evsel, TID);
> + evsel->core.attr.read_format |=
> + PERF_FORMAT_ID;
> }
> }
>
> @@ -1832,6 +1840,8 @@ static int __evsel__prepare_open(struct evsel *evsel, struct perf_cpu_map *cpus,
>
> static void evsel__disable_missing_features(struct evsel *evsel)
> {
> + if (perf_missing_features.inherit_sample_read)
> + evsel->core.attr.inherit = 0;
> if (perf_missing_features.branch_counters)
> evsel->core.attr.branch_sample_type &= ~PERF_SAMPLE_BRANCH_COUNTERS;
> if (perf_missing_features.read_lost)
> @@ -1887,7 +1897,12 @@ bool evsel__detect_missing_features(struct evsel *evsel)
> * Must probe features in the order they were added to the
> * perf_event_attr interface.
> */
> - if (!perf_missing_features.branch_counters &&
> + if (!perf_missing_features.inherit_sample_read &&
> + evsel->core.attr.inherit && (evsel->core.attr.sample_type & PERF_SAMPLE_READ)) {
> + perf_missing_features.inherit_sample_read = true;
> + pr_debug2("Using PERF_SAMPLE_READ / :S modifier is not compatible with inherit, falling back to no-inherit.\n");
> + return true;
> + } else if (!perf_missing_features.branch_counters &&
> (evsel->core.attr.branch_sample_type & PERF_SAMPLE_BRANCH_COUNTERS)) {
> perf_missing_features.branch_counters = true;
> pr_debug2("switching off branch counters support\n");
> diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
> index 517cff431de20..21b8b7e70e75e 100644
> --- a/tools/perf/util/evsel.h
> +++ b/tools/perf/util/evsel.h
> @@ -192,6 +192,7 @@ struct perf_missing_features {
> bool weight_struct;
> bool read_lost;
> bool branch_counters;
> + bool inherit_sample_read;
> };
>
> extern struct perf_missing_features perf_missing_features;
> --
> 2.45.1
>
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