* [PATCH v11 1/2] tools/perf: Correctly calculate sample period for inherited SAMPLE_READ values
2024-08-05 8:54 [PATCH v11 0/2] tools/perf: Support PERF_SAMPLE_READ with inherit Ben Gainey
@ 2024-08-05 8:54 ` Ben Gainey
2024-08-05 8:54 ` [PATCH v11 2/2] tools/perf: Allow inherit + PERF_SAMPLE_READ when opening events Ben Gainey
2024-09-27 22:49 ` [PATCH v11 0/2] tools/perf: Support PERF_SAMPLE_READ with inherit Namhyung Kim
2 siblings, 0 replies; 4+ messages in thread
From: Ben Gainey @ 2024-08-05 8:54 UTC (permalink / raw)
To: peterz, mingo, acme, namhyung
Cc: james.clark, mark.rutland, alexander.shishkin, jolsa, irogers,
adrian.hunter, linux-perf-users, linux-kernel, Ben Gainey
Sample period calculation in deliver_sample_value is updated to
calculate the per-thread period delta for events that are inherit +
PERF_SAMPLE_READ. When the sampling event has this configuration, the
read_format.id is used with the tid from the sample to lookup the
storage of the previously accumulated counter total before calculating
the delta. All existing valid configurations where read_format.value
represents some global value continue to use just the read_format.id to
locate the storage of the previously accumulated total.
perf_sample_id is modified to support tracking per-thread
values, along with the existing global per-id values. In the
per-thread case, values are stored in a hash by tid within the
perf_sample_id, and are dynamically allocated as the number is not known
ahead of time.
Signed-off-by: Ben Gainey <ben.gainey@arm.com>
---
tools/lib/perf/evsel.c | 48 +++++++++++++++++++
tools/lib/perf/include/internal/evsel.h | 63 ++++++++++++++++++++++++-
tools/perf/util/session.c | 25 ++++++----
3 files changed, 126 insertions(+), 10 deletions(-)
diff --git a/tools/lib/perf/evsel.c b/tools/lib/perf/evsel.c
index c07160953224..c475319e2e41 100644
--- a/tools/lib/perf/evsel.c
+++ b/tools/lib/perf/evsel.c
@@ -5,6 +5,7 @@
#include <perf/evsel.h>
#include <perf/cpumap.h>
#include <perf/threadmap.h>
+#include <linux/hash.h>
#include <linux/list.h>
#include <internal/evsel.h>
#include <linux/zalloc.h>
@@ -23,6 +24,7 @@ void perf_evsel__init(struct perf_evsel *evsel, struct perf_event_attr *attr,
int idx)
{
INIT_LIST_HEAD(&evsel->node);
+ INIT_LIST_HEAD(&evsel->per_stream_periods);
evsel->attr = *attr;
evsel->idx = idx;
evsel->leader = evsel;
@@ -531,10 +533,56 @@ int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads)
void perf_evsel__free_id(struct perf_evsel *evsel)
{
+ struct perf_sample_id_period *pos, *n;
+
xyarray__delete(evsel->sample_id);
evsel->sample_id = NULL;
zfree(&evsel->id);
evsel->ids = 0;
+
+ perf_evsel_for_each_per_thread_period_safe(evsel, n, pos) {
+ list_del_init(&pos->node);
+ free(pos);
+ }
+}
+
+bool perf_evsel__attr_has_per_thread_sample_period(struct perf_evsel *evsel)
+{
+ return (evsel->attr.sample_type & PERF_SAMPLE_READ) &&
+ (evsel->attr.sample_type & PERF_SAMPLE_TID) &&
+ evsel->attr.inherit;
+}
+
+u64 *perf_sample_id__get_period_storage(struct perf_sample_id *sid, u32 tid, bool per_thread)
+{
+ struct hlist_head *head;
+ struct perf_sample_id_period *res;
+ int hash;
+
+ if (!per_thread)
+ return &sid->period;
+
+ hash = hash_32(tid, PERF_SAMPLE_ID__HLIST_BITS);
+ head = &sid->periods[hash];
+
+ hlist_for_each_entry(res, head, hnode)
+ if (res->tid == tid)
+ return &res->period;
+
+ if (sid->evsel == NULL)
+ return NULL;
+
+ res = zalloc(sizeof(struct perf_sample_id_period));
+ if (res == NULL)
+ return NULL;
+
+ INIT_LIST_HEAD(&res->node);
+ res->tid = tid;
+
+ list_add_tail(&res->node, &sid->evsel->per_stream_periods);
+ hlist_add_head(&res->hnode, &sid->periods[hash]);
+
+ return &res->period;
}
void perf_counts_values__scale(struct perf_counts_values *count,
diff --git a/tools/lib/perf/include/internal/evsel.h b/tools/lib/perf/include/internal/evsel.h
index 5cd220a61962..ea78defa77d0 100644
--- a/tools/lib/perf/include/internal/evsel.h
+++ b/tools/lib/perf/include/internal/evsel.h
@@ -11,6 +11,32 @@
struct perf_thread_map;
struct xyarray;
+/**
+ * The per-thread accumulated period storage node.
+ */
+struct perf_sample_id_period {
+ struct list_head node;
+ struct hlist_node hnode;
+ /* Holds total ID period value for PERF_SAMPLE_READ processing. */
+ u64 period;
+ /* The TID that the values belongs to */
+ u32 tid;
+};
+
+/**
+ * perf_evsel_for_each_per_thread_period_safe - safely iterate thru all the
+ * per_stream_periods
+ * @evlist:perf_evsel instance to iterate
+ * @item: struct perf_sample_id_period iterator
+ * @tmp: struct perf_sample_id_period temp iterator
+ */
+#define perf_evsel_for_each_per_thread_period_safe(evsel, tmp, item) \
+ list_for_each_entry_safe(item, tmp, &(evsel)->per_stream_periods, node)
+
+
+#define PERF_SAMPLE_ID__HLIST_BITS 4
+#define PERF_SAMPLE_ID__HLIST_SIZE (1 << PERF_SAMPLE_ID__HLIST_BITS)
+
/*
* Per fd, to map back from PERF_SAMPLE_ID to evsel, only used when there are
* more than one entry in the evlist.
@@ -34,8 +60,32 @@ struct perf_sample_id {
pid_t machine_pid;
struct perf_cpu vcpu;
- /* Holds total ID period value for PERF_SAMPLE_READ processing. */
- u64 period;
+ /*
+ * Per-thread, and global event counts are mutually exclusive:
+ * Whilst it is possible to combine events into a group with differing
+ * values of PERF_SAMPLE_READ, it is not valid to have inconsistent
+ * values for `inherit`. Therefore it is not possible to have a
+ * situation where a per-thread event is sampled as a global event;
+ * all !inherit groups are global, and all groups where the sampling
+ * event is inherit + PERF_SAMPLE_READ will be per-thread. Any event
+ * that is part of such a group that is inherit but not PERF_SAMPLE_READ
+ * will be read as per-thread. If such an event can also trigger a
+ * sample (such as with sample_period > 0) then it will not cause
+ * `read_format` to be included in its PERF_RECORD_SAMPLE, and
+ * therefore will not expose the per-thread group members as global.
+ */
+ union {
+ /*
+ * Holds total ID period value for PERF_SAMPLE_READ processing
+ * (when period is not per-thread).
+ */
+ u64 period;
+ /*
+ * Holds total ID period value for PERF_SAMPLE_READ processing
+ * (when period is per-thread).
+ */
+ struct hlist_head periods[PERF_SAMPLE_ID__HLIST_SIZE];
+ };
};
struct perf_evsel {
@@ -58,6 +108,10 @@ struct perf_evsel {
u32 ids;
struct perf_evsel *leader;
+ /* For events where the read_format value is per-thread rather than
+ * global, stores the per-thread cumulative period */
+ struct list_head per_stream_periods;
+
/* parse modifier helper */
int nr_members;
/*
@@ -88,4 +142,9 @@ int perf_evsel__apply_filter(struct perf_evsel *evsel, const char *filter);
int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads);
void perf_evsel__free_id(struct perf_evsel *evsel);
+bool perf_evsel__attr_has_per_thread_sample_period(struct perf_evsel *evsel);
+
+u64 *perf_sample_id__get_period_storage(struct perf_sample_id *sid, u32 tid,
+ bool per_thread);
+
#endif /* __LIBPERF_INTERNAL_EVSEL_H */
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 5596bed1b8c8..fac0557ff6ea 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -1474,18 +1474,24 @@ static int deliver_sample_value(struct evlist *evlist,
union perf_event *event,
struct perf_sample *sample,
struct sample_read_value *v,
- struct machine *machine)
+ struct machine *machine,
+ bool per_thread)
{
struct perf_sample_id *sid = evlist__id2sid(evlist, v->id);
struct evsel *evsel;
+ u64 *storage = NULL;
if (sid) {
+ storage = perf_sample_id__get_period_storage(sid, sample->tid, per_thread);
+ }
+
+ if (storage) {
sample->id = v->id;
- sample->period = v->value - sid->period;
- sid->period = v->value;
+ sample->period = v->value - *storage;
+ *storage = v->value;
}
- if (!sid || sid->evsel == NULL) {
+ if (!storage || sid->evsel == NULL) {
++evlist->stats.nr_unknown_id;
return 0;
}
@@ -1506,14 +1512,15 @@ static int deliver_sample_group(struct evlist *evlist,
union perf_event *event,
struct perf_sample *sample,
struct machine *machine,
- u64 read_format)
+ u64 read_format,
+ bool per_thread)
{
int ret = -EINVAL;
struct sample_read_value *v = sample->read.group.values;
sample_read_group__for_each(v, sample->read.group.nr, read_format) {
ret = deliver_sample_value(evlist, tool, event, sample, v,
- machine);
+ machine, per_thread);
if (ret)
break;
}
@@ -1528,6 +1535,7 @@ static int evlist__deliver_sample(struct evlist *evlist, struct perf_tool *tool,
/* We know evsel != NULL. */
u64 sample_type = evsel->core.attr.sample_type;
u64 read_format = evsel->core.attr.read_format;
+ bool per_thread = perf_evsel__attr_has_per_thread_sample_period(&evsel->core);
/* Standard sample delivery. */
if (!(sample_type & PERF_SAMPLE_READ))
@@ -1536,10 +1544,11 @@ static int evlist__deliver_sample(struct evlist *evlist, struct perf_tool *tool,
/* For PERF_SAMPLE_READ we have either single or group mode. */
if (read_format & PERF_FORMAT_GROUP)
return deliver_sample_group(evlist, tool, event, sample,
- machine, read_format);
+ machine, read_format, per_thread);
else
return deliver_sample_value(evlist, tool, event, sample,
- &sample->read.one, machine);
+ &sample->read.one, machine,
+ per_thread);
}
static int machines__deliver_event(struct machines *machines,
--
2.45.2
^ permalink raw reply related [flat|nested] 4+ messages in thread* [PATCH v11 2/2] tools/perf: Allow inherit + PERF_SAMPLE_READ when opening events
2024-08-05 8:54 [PATCH v11 0/2] tools/perf: Support PERF_SAMPLE_READ with inherit Ben Gainey
2024-08-05 8:54 ` [PATCH v11 1/2] tools/perf: Correctly calculate sample period for inherited SAMPLE_READ values Ben Gainey
@ 2024-08-05 8:54 ` Ben Gainey
2024-09-27 22:49 ` [PATCH v11 0/2] tools/perf: Support PERF_SAMPLE_READ with inherit Namhyung Kim
2 siblings, 0 replies; 4+ messages in thread
From: Ben Gainey @ 2024-08-05 8:54 UTC (permalink / raw)
To: peterz, mingo, acme, namhyung
Cc: james.clark, mark.rutland, alexander.shishkin, jolsa, irogers,
adrian.hunter, linux-perf-users, linux-kernel, Ben Gainey
The "perf record" 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 +
tools/perf/tests/attr/test-record-C0 | 2 +
tools/perf/tests/attr/test-record-dummy-C0 | 2 +-
.../tests/attr/test-record-group-sampling | 3 +-
.../tests/attr/test-record-group-sampling1 | 51 ++++++++++++++++
.../tests/attr/test-record-group-sampling2 | 61 +++++++++++++++++++
tools/perf/tests/attr/test-record-group2 | 1 +
...{test-record-group2 => test-record-group3} | 10 +--
tools/perf/util/evsel.c | 21 ++++++-
tools/perf/util/evsel.h | 1 +
10 files changed, 145 insertions(+), 9 deletions(-)
create mode 100644 tools/perf/tests/attr/test-record-group-sampling1
create mode 100644 tools/perf/tests/attr/test-record-group-sampling2
copy tools/perf/tests/attr/{test-record-group2 => test-record-group3} (81%)
diff --git a/tools/perf/tests/attr/README b/tools/perf/tests/attr/README
index 4066fec7180a..67c4ca76b85d 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-C0 b/tools/perf/tests/attr/test-record-C0
index 198e8429a1bf..1049ac8b52f2 100644
--- a/tools/perf/tests/attr/test-record-C0
+++ b/tools/perf/tests/attr/test-record-C0
@@ -18,5 +18,7 @@ sample_type=65927
mmap=0
comm=0
task=0
+inherit=0
[event:system-wide-dummy]
+inherit=0
diff --git a/tools/perf/tests/attr/test-record-dummy-C0 b/tools/perf/tests/attr/test-record-dummy-C0
index 576ec48b3aaf..3050298bd614 100644
--- a/tools/perf/tests/attr/test-record-dummy-C0
+++ b/tools/perf/tests/attr/test-record-dummy-C0
@@ -19,7 +19,7 @@ sample_period=4000
sample_type=391
read_format=4|20
disabled=0
-inherit=1
+inherit=0
pinned=0
exclusive=0
exclude_user=0
diff --git a/tools/perf/tests/attr/test-record-group-sampling b/tools/perf/tests/attr/test-record-group-sampling
index 97e7e64a38f0..86a940d7895d 100644
--- a/tools/perf/tests/attr/test-record-group-sampling
+++ b/tools/perf/tests/attr/test-record-group-sampling
@@ -2,6 +2,7 @@
command = record
args = --no-bpf-event -e '{cycles,cache-misses}:S' kill >/dev/null 2>&1
ret = 1
+kernel_until = 6.12
[event-1:base-record]
fd=1
@@ -18,7 +19,7 @@ group_fd=1
type=0
config=3
-# default | PERF_SAMPLE_READ
+# default | PERF_SAMPLE_READ | PERF_SAMPLE_PERIOD
sample_type=343
# PERF_FORMAT_ID | PERF_FORMAT_GROUP | PERF_FORMAT_LOST
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 000000000000..e96a10627a46
--- /dev/null
+++ b/tools/perf/tests/attr/test-record-group-sampling1
@@ -0,0 +1,51 @@
+[config]
+command = record
+args = --no-bpf-event -e '{cycles,cache-misses}:S' kill >/dev/null 2>&1
+ret = 1
+kernel_since = 6.12
+
+[event-1:base-record]
+fd=1
+group_fd=-1
+
+# cycles
+type=0
+config=0
+
+# default | PERF_SAMPLE_READ | PERF_SAMPLE_PERIOD
+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 | PERF_SAMPLE_PERIOD
+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 000000000000..e0432244a0eb
--- /dev/null
+++ b/tools/perf/tests/attr/test-record-group-sampling2
@@ -0,0 +1,61 @@
+[config]
+command = record
+args = --no-bpf-event -c 10000 -e '{cycles,cache-misses}:S' kill >/dev/null 2>&1
+ret = 1
+kernel_since = 6.12
+
+[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 cebdaa8e64e4..891d41a7bddf 100644
--- a/tools/perf/tests/attr/test-record-group2
+++ b/tools/perf/tests/attr/test-record-group2
@@ -2,6 +2,7 @@
command = record
args = --no-bpf-event -e '{cycles/period=1234000/,instructions/period=6789000/}:S' kill >/dev/null 2>&1
ret = 1
+kernel_until = 6.12
[event-1:base-record]
fd=1
diff --git a/tools/perf/tests/attr/test-record-group2 b/tools/perf/tests/attr/test-record-group3
similarity index 81%
copy from tools/perf/tests/attr/test-record-group2
copy to tools/perf/tests/attr/test-record-group3
index cebdaa8e64e4..249be884959e 100644
--- a/tools/perf/tests/attr/test-record-group2
+++ b/tools/perf/tests/attr/test-record-group3
@@ -2,6 +2,7 @@
command = record
args = --no-bpf-event -e '{cycles/period=1234000/,instructions/period=6789000/}:S' kill >/dev/null 2>&1
ret = 1
+kernel_since = 6.12
[event-1:base-record]
fd=1
@@ -9,8 +10,9 @@ 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 +21,9 @@ 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 bc603193c477..d12e1b16313d 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1149,7 +1149,7 @@ void evsel__config(struct evsel *evsel, struct record_opts *opts,
bool per_cpu = opts->target.default_per_cpu && !opts->target.per_thread;
attr->sample_id_all = perf_missing_features.sample_id_all ? 0 : 1;
- attr->inherit = !opts->no_inherit;
+ attr->inherit = target__has_cpu(&opts->target) ? 0 : !opts->no_inherit;
attr->write_backward = opts->overwrite ? 1 : 0;
attr->read_format = PERF_FORMAT_LOST;
@@ -1171,7 +1171,15 @@ 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;
}
}
@@ -2020,6 +2028,8 @@ 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)
@@ -2075,7 +2085,12 @@ 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 80b5f6dd868e..bb0c91c23679 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -206,6 +206,7 @@ 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;
--
2.45.2
^ permalink raw reply related [flat|nested] 4+ messages in thread