Commit 84e62914 authored by Ian Rogers's avatar Ian Rogers Committed by Arnaldo Carvalho de Melo
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perf intel-tpebs: Inline get_perf_record_args 



Code is short enough to be inlined and there are no error cases when
made inline.

Make the implicit NULL pointer at the end of the argv explicit.

Move the fixed number of arguments before the variable number of
arguments.

Correctly size the argv allocation and zero when feeing to avoid a
dangling pointer.

Reviewed-by: default avatarKan Liang <kan.liang@linux.intel.com>
Signed-off-by: default avatarIan Rogers <irogers@google.com>
Tested-by: default avatarWeilin Wang <weilin.wang@intel.com>
Acked-by: default avatarNamhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexandre Torgue <alexandre.torgue@foss.st.com>
Cc: Andreas Färber <afaerber@suse.de>
Cc: Caleb Biggers <caleb.biggers@intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Perry Taylor <perry.taylor@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Falcon <thomas.falcon@intel.com>
Link: https://lore.kernel.org/r/20250414174134.3095492-8-irogers@google.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 728756ff

tools/perf/util/intel-tpebs.c

+28 −47
Original line number Diff line number Diff line
@@ -47,72 +47,53 @@ struct tpebs_retire_lat { 
	double val;

};



static int get_perf_record_args(const char **record_argv, char buf[],

				const char *cpumap_buf)

static int evsel__tpebs_start_perf_record(struct evsel *evsel, int control_fd[], int ack_fd[])

{

	struct tpebs_retire_lat *e;

	int i = 0;

	const char **record_argv;

	int tpebs_event_size = 0, i = 0, ret;

	char control_fd_buf[32];

	char cpumap_buf[50];

	struct tpebs_retire_lat *t;



	pr_debug("tpebs: Prepare perf record for retire_latency\n");

	list_for_each_entry(t, &tpebs_results, nd)

		tpebs_event_size++;



	record_argv = malloc((10 + 2 * tpebs_event_size) * sizeof(*record_argv));

	if (!record_argv)

		return -ENOMEM;



	record_argv[i++] = "perf";

	record_argv[i++] = "record";

	record_argv[i++] = "-W";

	record_argv[i++] = "--synth=no";

	record_argv[i++] = buf;



	if (!cpumap_buf) {

		pr_err("tpebs: Require cpumap list to run sampling\n");

		return -ECANCELED;

	}

	/* Use -C when cpumap_buf is not "-1" */

	if (strcmp(cpumap_buf, "-1")) {

		record_argv[i++] = "-C";

		record_argv[i++] = cpumap_buf;

	}



	list_for_each_entry(e, &tpebs_results, nd) {

		record_argv[i++] = "-e";

		record_argv[i++] = e->name;

	}

	scnprintf(control_fd_buf, sizeof(control_fd_buf), "--control=fd:%d,%d",

		  control_fd[0], ack_fd[1]);

	record_argv[i++] = control_fd_buf;



	record_argv[i++] = "-o";

	record_argv[i++] = PERF_DATA;



	return 0;

}



static int evsel__tpebs_start_perf_record(struct evsel *evsel, int control_fd[], int ack_fd[])

{

	const char **record_argv;

	size_t tpebs_event_size = 0;

	int ret;

	char buf[32];

	char cpumap_buf[50];

	struct tpebs_retire_lat *t;



	if (!perf_cpu_map__is_any_cpu_or_is_empty(evsel->evlist->core.user_requested_cpus)) {

		cpu_map__snprint(evsel->evlist->core.user_requested_cpus, cpumap_buf,

				 sizeof(cpumap_buf));

		record_argv[i++] = "-C";

		record_argv[i++] = cpumap_buf;

	}



	scnprintf(buf, sizeof(buf), "--control=fd:%d,%d", control_fd[0], ack_fd[1]);



	list_for_each_entry(t, &tpebs_results, nd)

		tpebs_event_size++;



	record_argv = calloc(12 + 2 * tpebs_event_size, sizeof(char *));

	if (!record_argv)

		return -ENOMEM;



	ret = get_perf_record_args(record_argv, buf, cpumap_buf);

	if (ret)

		goto out;

	list_for_each_entry(t, &tpebs_results, nd) {

		record_argv[i++] = "-e";

		record_argv[i++] = t->name;

	}

	record_argv[i++] = NULL;

	assert(i == 10 + 2 * tpebs_event_size || i == 8 + 2 * tpebs_event_size);

	/* Note, no workload given so system wide is implied. */



	assert(tpebs_cmd.pid == 0);

	tpebs_cmd.argv = record_argv;

	tpebs_cmd.out = -1;

	ret = start_command(&tpebs_cmd);

out:

	free(record_argv);

	zfree(&tpebs_cmd.argv);

	return ret;

}