When there are lost samples, it can read the number of PERF_FORMAT_LOST and
convert it to PERF_RECORD_LOST_SAMPLES and write to the data file at the end.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
tools/perf/builtin-record.c | 60 +++++++++++++++++++++++++++++++++++++
1 file changed, 60 insertions(+)
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index bce8c941d558..cb9881543a07 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -10,6 +10,7 @@
#include "util/build-id.h"
#include <subcmd/parse-options.h>
+#include <internal/xyarray.h>
#include "util/parse-events.h"
#include "util/config.h"
@@ -1852,6 +1853,64 @@ record__switch_output(struct record *rec, bool at_exit)
return fd;
}
+static void __record__read_lost_samples(struct record *rec, struct evsel *evsel,
+ struct perf_record_lost_samples *lost,
+ int size, int cpu_idx, int thread_idx)
+{
+ struct perf_counts_values count;
+ struct perf_sample_id *sid;
+ struct perf_sample sample = {};
+
+ if (perf_evsel__read(&evsel->core, cpu_idx, thread_idx, &count) < 0) {
+ pr_err("read LOST count failed\n");
+ return;
+ }
+
+ if (count.lost == 0)
+ return;
+
+ lost->lost = count.lost;
+ if (evsel->core.ids) {
+ sid = xyarray__entry(evsel->core.sample_id, cpu_idx, thread_idx);
+ sample.id = sid->id;
+ }
+
+ perf_event__synthesize_id_sample((void *)(lost + 1),
+ evsel->core.attr.sample_type, &sample);
+ record__write(rec, NULL, lost, size);
+}
+
+static void record__read_lost_samples(struct record *rec)
+{
+ struct perf_session *session = rec->session;
+ struct machine *machine = &session->machines.host;
+ struct perf_record_lost_samples *lost;
+ struct evsel *evsel;
+ int size = sizeof(*lost) + machine->id_hdr_size;
+
+ lost = zalloc(size);
+ lost->header.type = PERF_RECORD_LOST_SAMPLES;
+ lost->header.size = size;
+
+ evlist__for_each_entry(session->evlist, evsel) {
+ struct xyarray *xy = evsel->core.sample_id;
+
+ if (xyarray__max_x(evsel->core.fd) != xyarray__max_x(xy) ||
+ xyarray__max_y(evsel->core.fd) != xyarray__max_y(xy)) {
+ pr_debug("Unmatched FD vs. sample ID: skip reading LOST count\n");
+ continue;
+ }
+
+ for (int x = 0; x < xyarray__max_x(xy); x++) {
+ for (int y = 0; y < xyarray__max_y(xy); y++) {
+ __record__read_lost_samples(rec, evsel, lost,
+ size, x, y);
+ }
+ }
+ }
+
+}
+
static volatile int workload_exec_errno;
/*
@@ -2710,6 +2769,7 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
if (rec->off_cpu)
rec->bytes_written += off_cpu_write(rec->session);
+ record__read_lost_samples(rec);
record__synthesize(rec, true);
/* this will be recalculated during process_buildids() */
rec->samples = 0;
--
2.37.2.789.g6183377224-googOn 1/09/22 00:03, Namhyung Kim wrote:
> When there are lost samples, it can read the number of PERF_FORMAT_LOST and
> convert it to PERF_RECORD_LOST_SAMPLES and write to the data file at the end.
>
> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
> ---
> tools/perf/builtin-record.c | 60 +++++++++++++++++++++++++++++++++++++
> 1 file changed, 60 insertions(+)
>
> diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
> index bce8c941d558..cb9881543a07 100644
> --- a/tools/perf/builtin-record.c
> +++ b/tools/perf/builtin-record.c
> @@ -10,6 +10,7 @@
>
> #include "util/build-id.h"
> #include <subcmd/parse-options.h>
> +#include <internal/xyarray.h>
> #include "util/parse-events.h"
> #include "util/config.h"
>
> @@ -1852,6 +1853,64 @@ record__switch_output(struct record *rec, bool at_exit)
> return fd;
> }
>
> +static void __record__read_lost_samples(struct record *rec, struct evsel *evsel,
> + struct perf_record_lost_samples *lost,
> + int size, int cpu_idx, int thread_idx)
> +{
> + struct perf_counts_values count;
> + struct perf_sample_id *sid;
> + struct perf_sample sample = {};
> +
> + if (perf_evsel__read(&evsel->core, cpu_idx, thread_idx, &count) < 0) {
> + pr_err("read LOST count failed\n");
> + return;
> + }
> +
> + if (count.lost == 0)
> + return;
> +
> + lost->lost = count.lost;
> + if (evsel->core.ids) {
> + sid = xyarray__entry(evsel->core.sample_id, cpu_idx, thread_idx);
> + sample.id = sid->id;
> + }
> +
> + perf_event__synthesize_id_sample((void *)(lost + 1),
> + evsel->core.attr.sample_type, &sample);
The ID sample size can vary with sample_type and is not necessarily the same as
machine->id_hdr_size.
The following might be more robust:
id_hdr_size = perf_event__synthesize_id_sample((void *)(lost + 1), evsel->core.attr.sample_type, &sample);
lost->header.size = sizeof(*lost) + id_hdr_size;
> + record__write(rec, NULL, lost, size);
> +}
> +
> +static void record__read_lost_samples(struct record *rec)
> +{
> + struct perf_session *session = rec->session;
> + struct machine *machine = &session->machines.host;
> + struct perf_record_lost_samples *lost;
> + struct evsel *evsel;
> + int size = sizeof(*lost) + machine->id_hdr_size;
- int size = sizeof(*lost) + machine->id_hdr_size;
> +
> + lost = zalloc(size);
lost = zalloc(PERF_SAMPLE_MAX_SIZE);
> + lost->header.type = PERF_RECORD_LOST_SAMPLES;
> + lost->header.size = size;
- lost->header.size = size;
> +
> + evlist__for_each_entry(session->evlist, evsel) {
> + struct xyarray *xy = evsel->core.sample_id;
> +
> + if (xyarray__max_x(evsel->core.fd) != xyarray__max_x(xy) ||
> + xyarray__max_y(evsel->core.fd) != xyarray__max_y(xy)) {
> + pr_debug("Unmatched FD vs. sample ID: skip reading LOST count\n");
> + continue;
> + }
> +
> + for (int x = 0; x < xyarray__max_x(xy); x++) {
> + for (int y = 0; y < xyarray__max_y(xy); y++) {
> + __record__read_lost_samples(rec, evsel, lost,
> + size, x, y);
> + }
> + }
> + }
> +
> +}
> +
> static volatile int workload_exec_errno;
>
> /*
> @@ -2710,6 +2769,7 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
> if (rec->off_cpu)
> rec->bytes_written += off_cpu_write(rec->session);
>
> + record__read_lost_samples(rec);
> record__synthesize(rec, true);
> /* this will be recalculated during process_buildids() */
> rec->samples = 0;
Hi Adrian,
On Thu, Sep 1, 2022 at 4:23 AM Adrian Hunter <adrian.hunter@intel.com> wrote:
>
> On 1/09/22 00:03, Namhyung Kim wrote:
> > When there are lost samples, it can read the number of PERF_FORMAT_LOST and
> > convert it to PERF_RECORD_LOST_SAMPLES and write to the data file at the end.
> >
> > Signed-off-by: Namhyung Kim <namhyung@kernel.org>
> > ---
> > tools/perf/builtin-record.c | 60 +++++++++++++++++++++++++++++++++++++
> > 1 file changed, 60 insertions(+)
> >
> > diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
> > index bce8c941d558..cb9881543a07 100644
> > --- a/tools/perf/builtin-record.c
> > +++ b/tools/perf/builtin-record.c
> > @@ -10,6 +10,7 @@
> >
> > #include "util/build-id.h"
> > #include <subcmd/parse-options.h>
> > +#include <internal/xyarray.h>
> > #include "util/parse-events.h"
> > #include "util/config.h"
> >
> > @@ -1852,6 +1853,64 @@ record__switch_output(struct record *rec, bool at_exit)
> > return fd;
> > }
> >
> > +static void __record__read_lost_samples(struct record *rec, struct evsel *evsel,
> > + struct perf_record_lost_samples *lost,
> > + int size, int cpu_idx, int thread_idx)
> > +{
> > + struct perf_counts_values count;
> > + struct perf_sample_id *sid;
> > + struct perf_sample sample = {};
> > +
> > + if (perf_evsel__read(&evsel->core, cpu_idx, thread_idx, &count) < 0) {
> > + pr_err("read LOST count failed\n");
> > + return;
> > + }
> > +
> > + if (count.lost == 0)
> > + return;
> > +
> > + lost->lost = count.lost;
> > + if (evsel->core.ids) {
> > + sid = xyarray__entry(evsel->core.sample_id, cpu_idx, thread_idx);
> > + sample.id = sid->id;
> > + }
> > +
> > + perf_event__synthesize_id_sample((void *)(lost + 1),
> > + evsel->core.attr.sample_type, &sample);
>
> The ID sample size can vary with sample_type and is not necessarily the same as
> machine->id_hdr_size.
>
> The following might be more robust:
>
> id_hdr_size = perf_event__synthesize_id_sample((void *)(lost + 1), evsel->core.attr.sample_type, &sample);
> lost->header.size = sizeof(*lost) + id_hdr_size;
Will change.
Thanks for your review!
Namhyung
>
> > + record__write(rec, NULL, lost, size);
> > +}
> > +
> > +static void record__read_lost_samples(struct record *rec)
> > +{
> > + struct perf_session *session = rec->session;
> > + struct machine *machine = &session->machines.host;
> > + struct perf_record_lost_samples *lost;
> > + struct evsel *evsel;
> > + int size = sizeof(*lost) + machine->id_hdr_size;
>
> - int size = sizeof(*lost) + machine->id_hdr_size;
>
> > +
> > + lost = zalloc(size);
>
> lost = zalloc(PERF_SAMPLE_MAX_SIZE);
>
>
> > + lost->header.type = PERF_RECORD_LOST_SAMPLES;
> > + lost->header.size = size;
>
> - lost->header.size = size;
>
> > +
> > + evlist__for_each_entry(session->evlist, evsel) {
> > + struct xyarray *xy = evsel->core.sample_id;
> > +
> > + if (xyarray__max_x(evsel->core.fd) != xyarray__max_x(xy) ||
> > + xyarray__max_y(evsel->core.fd) != xyarray__max_y(xy)) {
> > + pr_debug("Unmatched FD vs. sample ID: skip reading LOST count\n");
> > + continue;
> > + }
> > +
> > + for (int x = 0; x < xyarray__max_x(xy); x++) {
> > + for (int y = 0; y < xyarray__max_y(xy); y++) {
> > + __record__read_lost_samples(rec, evsel, lost,
> > + size, x, y);
> > + }
> > + }
> > + }
> > +
> > +}
> > +
> > static volatile int workload_exec_errno;
> >
> > /*
> > @@ -2710,6 +2769,7 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
> > if (rec->off_cpu)
> > rec->bytes_written += off_cpu_write(rec->session);
> >
> > + record__read_lost_samples(rec);
> > record__synthesize(rec, true);
> > /* this will be recalculated during process_buildids() */
> > rec->samples = 0;
>
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