[PATCH v7 18/23] perf timechart: Don't pass evsel with sample

Ian Rogers
2026-04-08T07:26:48Z

The sample contains the evsel and so it is unnecessary to pass the
evsel as well. Add missing backtrace argument to tracepoint_handler
functions and mark them unused. Fix missing free from cat_backtrace,
which requires copies of the backtrace being made in functions that
save it.

Signed-off-by: Ian Rogers <irogers@google.com>
---
tools/perf/builtin-timechart.c | 81 ++++++++++++++++------------------
1 file changed, 39 insertions(+), 42 deletions(-)

diff --git a/tools/perf/builtin-timechart.c b/tools/perf/builtin-timechart.c
index 782ede4258a2..0db2a9bd5b91 100644
--- a/tools/perf/builtin-timechart.c
+++ b/tools/perf/builtin-timechart.c
@@ -299,7 +299,7 @@ static void pid_put_sample(struct timechart *tchart, int pid, int type,
sample->type = type;
sample->next = c->samples;
sample->cpu = cpu;
- sample->backtrace = backtrace;
+ sample->backtrace = backtrace ? strdup(backtrace) : NULL;
c->samples = sample;

if (sample->type == TYPE_RUNNING && end > start && start > 0) {
@@ -433,7 +433,7 @@ static void sched_wakeup(struct timechart *tchart, int cpu, u64 timestamp,

we->time = timestamp;
we->waker = waker;
- we->backtrace = backtrace;
+ we->backtrace = backtrace ? strdup(backtrace) : NULL;

if ((flags & TRACE_FLAG_HARDIRQ) || (flags & TRACE_FLAG_SOFTIRQ))
we->waker = -1;
@@ -489,9 +489,9 @@ static void sched_switch(struct timechart *tchart, int cpu, u64 timestamp,
}
}

-static const char *cat_backtrace(union perf_event *event,
- struct perf_sample *sample,
- struct machine *machine)
+static char *cat_backtrace(union perf_event *event,
+ struct perf_sample *sample,
+ struct machine *machine)
{
struct addr_location al;
unsigned int i;
@@ -544,8 +544,10 @@ static const char *cat_backtrace(union perf_event *event,
* It seems the callchain is corrupted.
* Discard all.
*/
- zfree(&p);
- goto exit;
+ addr_location__exit(&al);
+ fclose(f);
+ free(p);
+ return NULL;
}
continue;
}
@@ -567,7 +569,6 @@ static const char *cat_backtrace(union perf_event *event,
}

typedef int (*tracepoint_handler)(struct timechart *tchart,
- struct evsel *evsel,
struct perf_sample *sample,
const char *backtrace);

@@ -578,6 +579,7 @@ static int process_sample_event(const struct perf_tool *tool,
{
struct timechart *tchart = container_of(tool, struct timechart, tool);
struct evsel *evsel = sample->evsel;
+ int ret = 0;

if (evsel->core.attr.sample_type & PERF_SAMPLE_TIME) {
if (!tchart->first_time || tchart->first_time > sample->time)
@@ -588,16 +590,17 @@ static int process_sample_event(const struct perf_tool *tool,

if (evsel->handler != NULL) {
tracepoint_handler f = evsel->handler;
- return f(tchart, evsel, sample,
- cat_backtrace(event, sample, machine));
+ char *backtrace = cat_backtrace(event, sample, machine);
+
+ ret = f(tchart, sample, backtrace);
+ free(backtrace);
}

- return 0;
+ return ret;
}

static int
process_sample_cpu_idle(struct timechart *tchart __maybe_unused,
- struct evsel *evsel __maybe_unused,
struct perf_sample *sample,
const char *backtrace __maybe_unused)
{
@@ -617,7 +620,6 @@ process_sample_cpu_idle(struct timechart *tchart __maybe_unused,

static int
process_sample_cpu_frequency(struct timechart *tchart,
- struct evsel *evsel __maybe_unused,
struct perf_sample *sample,
const char *backtrace __maybe_unused)
{
@@ -634,7 +636,6 @@ process_sample_cpu_frequency(struct timechart *tchart,

static int
process_sample_sched_wakeup(struct timechart *tchart,
- struct evsel *evsel __maybe_unused,
struct perf_sample *sample,
const char *backtrace)
{
@@ -648,7 +649,6 @@ process_sample_sched_wakeup(struct timechart *tchart,

static int
process_sample_sched_switch(struct timechart *tchart,
- struct evsel *evsel __maybe_unused,
struct perf_sample *sample,
const char *backtrace)
{
@@ -664,7 +664,6 @@ process_sample_sched_switch(struct timechart *tchart,
#ifdef SUPPORT_OLD_POWER_EVENTS
static int
process_sample_power_start(struct timechart *tchart __maybe_unused,
- struct evsel *evsel __maybe_unused,
struct perf_sample *sample,
const char *backtrace __maybe_unused)
{
@@ -681,7 +680,6 @@ process_sample_power_start(struct timechart *tchart __maybe_unused,

static int
process_sample_power_end(struct timechart *tchart,
- struct evsel *evsel __maybe_unused,
struct perf_sample *sample,
const char *backtrace __maybe_unused)
{
@@ -691,7 +689,6 @@ process_sample_power_end(struct timechart *tchart,

static int
process_sample_power_frequency(struct timechart *tchart,
- struct evsel *evsel __maybe_unused,
struct perf_sample *sample,
const char *backtrace __maybe_unused)
{
@@ -865,8 +862,8 @@ static int pid_end_io_sample(struct timechart *tchart, int pid, int type,

static int
process_enter_read(struct timechart *tchart,
- struct evsel *evsel __maybe_unused,
- struct perf_sample *sample)
+ struct perf_sample *sample,
+ const char *backtrace __maybe_unused)
{
long fd = perf_sample__intval(sample, "fd");
return pid_begin_io_sample(tchart, sample->tid, IOTYPE_READ,
@@ -875,8 +872,8 @@ process_enter_read(struct timechart *tchart,

static int
process_exit_read(struct timechart *tchart,
- struct evsel *evsel __maybe_unused,
- struct perf_sample *sample)
+ struct perf_sample *sample,
+ const char *backtrace __maybe_unused)
{
long ret = perf_sample__intval(sample, "ret");
return pid_end_io_sample(tchart, sample->tid, IOTYPE_READ,
@@ -885,8 +882,8 @@ process_exit_read(struct timechart *tchart,

static int
process_enter_write(struct timechart *tchart,
- struct evsel *evsel __maybe_unused,
- struct perf_sample *sample)
+ struct perf_sample *sample,
+ const char *backtrace __maybe_unused)
{
long fd = perf_sample__intval(sample, "fd");
return pid_begin_io_sample(tchart, sample->tid, IOTYPE_WRITE,
@@ -895,8 +892,8 @@ process_enter_write(struct timechart *tchart,

static int
process_exit_write(struct timechart *tchart,
- struct evsel *evsel __maybe_unused,
- struct perf_sample *sample)
+ struct perf_sample *sample,
+ const char *backtrace __maybe_unused)
{
long ret = perf_sample__intval(sample, "ret");
return pid_end_io_sample(tchart, sample->tid, IOTYPE_WRITE,
@@ -905,8 +902,8 @@ process_exit_write(struct timechart *tchart,

static int
process_enter_sync(struct timechart *tchart,
- struct evsel *evsel __maybe_unused,
- struct perf_sample *sample)
+ struct perf_sample *sample,
+ const char *backtrace __maybe_unused)
{
long fd = perf_sample__intval(sample, "fd");
return pid_begin_io_sample(tchart, sample->tid, IOTYPE_SYNC,
@@ -915,8 +912,8 @@ process_enter_sync(struct timechart *tchart,

static int
process_exit_sync(struct timechart *tchart,
- struct evsel *evsel __maybe_unused,
- struct perf_sample *sample)
+ struct perf_sample *sample,
+ const char *backtrace __maybe_unused)
{
long ret = perf_sample__intval(sample, "ret");
return pid_end_io_sample(tchart, sample->tid, IOTYPE_SYNC,
@@ -925,8 +922,8 @@ process_exit_sync(struct timechart *tchart,

static int
process_enter_tx(struct timechart *tchart,
- struct evsel *evsel __maybe_unused,
- struct perf_sample *sample)
+ struct perf_sample *sample,
+ const char *backtrace __maybe_unused)
{
long fd = perf_sample__intval(sample, "fd");
return pid_begin_io_sample(tchart, sample->tid, IOTYPE_TX,
@@ -935,8 +932,8 @@ process_enter_tx(struct timechart *tchart,

static int
process_exit_tx(struct timechart *tchart,
- struct evsel *evsel __maybe_unused,
- struct perf_sample *sample)
+ struct perf_sample *sample,
+ const char *backtrace __maybe_unused)
{
long ret = perf_sample__intval(sample, "ret");
return pid_end_io_sample(tchart, sample->tid, IOTYPE_TX,
@@ -945,8 +942,8 @@ process_exit_tx(struct timechart *tchart,

static int
process_enter_rx(struct timechart *tchart,
- struct evsel *evsel __maybe_unused,
- struct perf_sample *sample)
+ struct perf_sample *sample,
+ const char *backtrace __maybe_unused)
{
long fd = perf_sample__intval(sample, "fd");
return pid_begin_io_sample(tchart, sample->tid, IOTYPE_RX,
@@ -955,8 +952,8 @@ process_enter_rx(struct timechart *tchart,

static int
process_exit_rx(struct timechart *tchart,
- struct evsel *evsel __maybe_unused,
- struct perf_sample *sample)
+ struct perf_sample *sample,
+ const char *backtrace __maybe_unused)
{
long ret = perf_sample__intval(sample, "ret");
return pid_end_io_sample(tchart, sample->tid, IOTYPE_RX,
@@ -965,8 +962,8 @@ process_exit_rx(struct timechart *tchart,

static int
process_enter_poll(struct timechart *tchart,
- struct evsel *evsel __maybe_unused,
- struct perf_sample *sample)
+ struct perf_sample *sample,
+ const char *backtrace __maybe_unused)
{
long fd = perf_sample__intval(sample, "fd");
return pid_begin_io_sample(tchart, sample->tid, IOTYPE_POLL,
@@ -975,8 +972,8 @@ process_enter_poll(struct timechart *tchart,

static int
process_exit_poll(struct timechart *tchart,
- struct evsel *evsel __maybe_unused,
- struct perf_sample *sample)
+ struct perf_sample *sample,
+ const char *backtrace __maybe_unused)
{
long ret = perf_sample__intval(sample, "ret");
return pid_end_io_sample(tchart, sample->tid, IOTYPE_POLL,
--
2.53.0.1213.gd9a14994de-goog