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Diffstat (limited to 'tools/perf/builtin-ftrace.c')
-rw-r--r--tools/perf/builtin-ftrace.c283
1 files changed, 246 insertions, 37 deletions
diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c
index cfd770ec7286..6b6eec65f93f 100644
--- a/tools/perf/builtin-ftrace.c
+++ b/tools/perf/builtin-ftrace.c
@@ -19,6 +19,7 @@
#include <ctype.h>
#include <linux/capability.h>
#include <linux/string.h>
+#include <sys/stat.h>
#include "debug.h"
#include <subcmd/pager.h>
@@ -45,6 +46,8 @@ static volatile sig_atomic_t done;
static struct stats latency_stats; /* for tracepoints */
+static char tracing_instance[PATH_MAX]; /* Trace instance directory */
+
static void sig_handler(int sig __maybe_unused)
{
done = true;
@@ -100,6 +103,34 @@ static bool is_ftrace_supported(void)
return supported;
}
+/*
+ * Wrapper to test if a file in directory .../tracing/instances/XXX
+ * exists. If so return the .../tracing/instances/XXX file for use.
+ * Otherwise the file exists only in directory .../tracing and
+ * is applicable to all instances, for example file available_filter_functions.
+ * Return that file name in this case.
+ *
+ * This functions works similar to get_tracing_file() and expects its caller
+ * to free the returned file name.
+ *
+ * The global variable tracing_instance is set in init_tracing_instance()
+ * called at the beginning to a process specific tracing subdirectory.
+ */
+static char *get_tracing_instance_file(const char *name)
+{
+ char *file;
+
+ if (asprintf(&file, "%s/%s", tracing_instance, name) < 0)
+ return NULL;
+
+ if (!access(file, F_OK))
+ return file;
+
+ free(file);
+ file = get_tracing_file(name);
+ return file;
+}
+
static int __write_tracing_file(const char *name, const char *val, bool append)
{
char *file;
@@ -109,7 +140,7 @@ static int __write_tracing_file(const char *name, const char *val, bool append)
char errbuf[512];
char *val_copy;
- file = get_tracing_file(name);
+ file = get_tracing_instance_file(name);
if (!file) {
pr_debug("cannot get tracing file: %s\n", name);
return -1;
@@ -167,7 +198,7 @@ static int read_tracing_file_to_stdout(const char *name)
int fd;
int ret = -1;
- file = get_tracing_file(name);
+ file = get_tracing_instance_file(name);
if (!file) {
pr_debug("cannot get tracing file: %s\n", name);
return -1;
@@ -209,7 +240,7 @@ static int read_tracing_file_by_line(const char *name,
char *file;
FILE *fp;
- file = get_tracing_file(name);
+ file = get_tracing_instance_file(name);
if (!file) {
pr_debug("cannot get tracing file: %s\n", name);
return -1;
@@ -270,6 +301,10 @@ static void reset_tracing_options(struct perf_ftrace *ftrace __maybe_unused)
write_tracing_option_file("funcgraph-proc", "0");
write_tracing_option_file("funcgraph-abstime", "0");
write_tracing_option_file("funcgraph-tail", "0");
+ write_tracing_option_file("funcgraph-args", "0");
+ write_tracing_option_file("funcgraph-retval", "0");
+ write_tracing_option_file("funcgraph-retval-hex", "0");
+ write_tracing_option_file("funcgraph-retaddr", "0");
write_tracing_option_file("latency-format", "0");
write_tracing_option_file("irq-info", "0");
}
@@ -299,6 +334,39 @@ static int reset_tracing_files(struct perf_ftrace *ftrace __maybe_unused)
return 0;
}
+/* Remove .../tracing/instances/XXX subdirectory created with
+ * init_tracing_instance().
+ */
+static void exit_tracing_instance(void)
+{
+ if (rmdir(tracing_instance))
+ pr_err("failed to delete tracing/instances directory\n");
+}
+
+/* Create subdirectory within .../tracing/instances/XXX to have session
+ * or process specific setup. To delete this setup, simply remove the
+ * subdirectory.
+ */
+static int init_tracing_instance(void)
+{
+ char dirname[] = "instances/perf-ftrace-XXXXXX";
+ char *path;
+
+ path = get_tracing_file(dirname);
+ if (!path)
+ goto error;
+ strncpy(tracing_instance, path, sizeof(tracing_instance) - 1);
+ put_tracing_file(path);
+ path = mkdtemp(tracing_instance);
+ if (!path)
+ goto error;
+ return 0;
+
+error:
+ pr_err("failed to create tracing/instances directory\n");
+ return -1;
+}
+
static int set_tracing_pid(struct perf_ftrace *ftrace)
{
int i;
@@ -478,6 +546,41 @@ static int set_tracing_sleep_time(struct perf_ftrace *ftrace)
return 0;
}
+static int set_tracing_funcgraph_args(struct perf_ftrace *ftrace)
+{
+ if (ftrace->graph_args) {
+ if (write_tracing_option_file("funcgraph-args", "1") < 0)
+ return -1;
+ }
+
+ return 0;
+}
+
+static int set_tracing_funcgraph_retval(struct perf_ftrace *ftrace)
+{
+ if (ftrace->graph_retval || ftrace->graph_retval_hex) {
+ if (write_tracing_option_file("funcgraph-retval", "1") < 0)
+ return -1;
+ }
+
+ if (ftrace->graph_retval_hex) {
+ if (write_tracing_option_file("funcgraph-retval-hex", "1") < 0)
+ return -1;
+ }
+
+ return 0;
+}
+
+static int set_tracing_funcgraph_retaddr(struct perf_ftrace *ftrace)
+{
+ if (ftrace->graph_retaddr) {
+ if (write_tracing_option_file("funcgraph-retaddr", "1") < 0)
+ return -1;
+ }
+
+ return 0;
+}
+
static int set_tracing_funcgraph_irqs(struct perf_ftrace *ftrace)
{
if (!ftrace->graph_noirqs)
@@ -578,6 +681,21 @@ static int set_tracing_options(struct perf_ftrace *ftrace)
return -1;
}
+ if (set_tracing_funcgraph_args(ftrace) < 0) {
+ pr_err("failed to set tracing option funcgraph-args\n");
+ return -1;
+ }
+
+ if (set_tracing_funcgraph_retval(ftrace) < 0) {
+ pr_err("failed to set tracing option funcgraph-retval\n");
+ return -1;
+ }
+
+ if (set_tracing_funcgraph_retaddr(ftrace) < 0) {
+ pr_err("failed to set tracing option funcgraph-retaddr\n");
+ return -1;
+ }
+
if (set_tracing_funcgraph_irqs(ftrace) < 0) {
pr_err("failed to set tracing option funcgraph-irqs\n");
return -1;
@@ -629,14 +747,17 @@ static int __cmd_ftrace(struct perf_ftrace *ftrace)
select_tracer(ftrace);
+ if (init_tracing_instance() < 0)
+ goto out;
+
if (reset_tracing_files(ftrace) < 0) {
pr_err("failed to reset ftrace\n");
- goto out;
+ goto out_reset;
}
/* reset ftrace buffer */
if (write_tracing_file("trace", "0") < 0)
- goto out;
+ goto out_reset;
if (set_tracing_options(ftrace) < 0)
goto out_reset;
@@ -648,7 +769,7 @@ static int __cmd_ftrace(struct perf_ftrace *ftrace)
setup_pager();
- trace_file = get_tracing_file("trace_pipe");
+ trace_file = get_tracing_instance_file("trace_pipe");
if (!trace_file) {
pr_err("failed to open trace_pipe\n");
goto out_reset;
@@ -723,7 +844,7 @@ static int __cmd_ftrace(struct perf_ftrace *ftrace)
out_close_fd:
close(trace_fd);
out_reset:
- reset_tracing_files(ftrace);
+ exit_tracing_instance();
out:
return (done && !workload_exec_errno) ? 0 : -1;
}
@@ -733,6 +854,7 @@ static void make_histogram(struct perf_ftrace *ftrace, int buckets[],
{
int min_latency = ftrace->min_latency;
int max_latency = ftrace->max_latency;
+ unsigned int bucket_num = ftrace->bucket_num;
char *p, *q;
char *unit;
double num;
@@ -797,10 +919,10 @@ static void make_histogram(struct perf_ftrace *ftrace, int buckets[],
if (num > 0) // 1st entry: [ 1 unit .. bucket_range units ]
i = num / ftrace->bucket_range + 1;
if (num >= max_latency - min_latency)
- i = NUM_BUCKET -1;
+ i = bucket_num -1;
}
- if (i >= NUM_BUCKET)
- i = NUM_BUCKET - 1;
+ if ((unsigned)i >= bucket_num)
+ i = bucket_num - 1;
num += min_latency;
do_inc:
@@ -820,13 +942,14 @@ static void display_histogram(struct perf_ftrace *ftrace, int buckets[])
{
int min_latency = ftrace->min_latency;
bool use_nsec = ftrace->use_nsec;
- int i;
+ unsigned int bucket_num = ftrace->bucket_num;
+ unsigned int i;
int total = 0;
int bar_total = 46; /* to fit in 80 column */
char bar[] = "###############################################";
int bar_len;
- for (i = 0; i < NUM_BUCKET; i++)
+ for (i = 0; i < bucket_num; i++)
total += buckets[i];
if (total == 0) {
@@ -839,14 +962,17 @@ static void display_histogram(struct perf_ftrace *ftrace, int buckets[])
bar_len = buckets[0] * bar_total / total;
- printf(" %4d - %4d %s | %10d | %.*s%*s |\n",
- 0, min_latency ?: 1, use_nsec ? "ns" : "us",
- buckets[0], bar_len, bar, bar_total - bar_len, "");
+ if (!ftrace->hide_empty || buckets[0])
+ printf(" %4d - %4d %s | %10d | %.*s%*s |\n",
+ 0, min_latency ?: 1, use_nsec ? "ns" : "us",
+ buckets[0], bar_len, bar, bar_total - bar_len, "");
- for (i = 1; i < NUM_BUCKET - 1; i++) {
+ for (i = 1; i < bucket_num - 1; i++) {
unsigned int start, stop;
const char *unit = use_nsec ? "ns" : "us";
+ if (ftrace->hide_empty && !buckets[i])
+ continue;
if (!ftrace->bucket_range) {
start = (1 << (i - 1));
stop = 1 << i;
@@ -881,11 +1007,13 @@ print_bucket_info:
bar_total - bar_len, "");
}
- bar_len = buckets[NUM_BUCKET - 1] * bar_total / total;
+ bar_len = buckets[bucket_num - 1] * bar_total / total;
+ if (ftrace->hide_empty && !buckets[bucket_num - 1])
+ goto print_stats;
if (!ftrace->bucket_range) {
printf(" %4d - %-4s %s", 1, "...", use_nsec ? "ms" : "s ");
} else {
- unsigned int upper_outlier = (NUM_BUCKET - 2) * ftrace->bucket_range + min_latency;
+ unsigned int upper_outlier = (bucket_num - 2) * ftrace->bucket_range + min_latency;
if (upper_outlier > ftrace->max_latency)
upper_outlier = ftrace->max_latency;
@@ -897,9 +1025,10 @@ print_bucket_info:
printf(" %4d - %4s %s", upper_outlier, "...", use_nsec ? "ns" : "us");
}
}
- printf(" | %10d | %.*s%*s |\n", buckets[NUM_BUCKET - 1],
+ printf(" | %10d | %.*s%*s |\n", buckets[bucket_num - 1],
bar_len, bar, bar_total - bar_len, "");
+print_stats:
printf("\n# statistics (in %s)\n", ftrace->use_nsec ? "nsec" : "usec");
printf(" total time: %20.0f\n", latency_stats.mean * latency_stats.n);
printf(" avg time: %20.0f\n", latency_stats.mean);
@@ -916,6 +1045,9 @@ static int prepare_func_latency(struct perf_ftrace *ftrace)
if (ftrace->target.use_bpf)
return perf_ftrace__latency_prepare_bpf(ftrace);
+ if (init_tracing_instance() < 0)
+ return -1;
+
if (reset_tracing_files(ftrace) < 0) {
pr_err("failed to reset ftrace\n");
return -1;
@@ -934,7 +1066,7 @@ static int prepare_func_latency(struct perf_ftrace *ftrace)
return -1;
}
- trace_file = get_tracing_file("trace_pipe");
+ trace_file = get_tracing_instance_file("trace_pipe");
if (!trace_file) {
pr_err("failed to open trace_pipe\n");
return -1;
@@ -985,7 +1117,7 @@ static int cleanup_func_latency(struct perf_ftrace *ftrace)
if (ftrace->target.use_bpf)
return perf_ftrace__latency_cleanup_bpf(ftrace);
- reset_tracing_files(ftrace);
+ exit_tracing_instance();
return 0;
}
@@ -997,7 +1129,7 @@ static int __cmd_latency(struct perf_ftrace *ftrace)
struct pollfd pollfd = {
.events = POLLIN,
};
- int buckets[NUM_BUCKET] = { };
+ int *buckets;
trace_fd = prepare_func_latency(ftrace);
if (trace_fd < 0)
@@ -1011,6 +1143,12 @@ static int __cmd_latency(struct perf_ftrace *ftrace)
evlist__start_workload(ftrace->evlist);
+ buckets = calloc(ftrace->bucket_num, sizeof(*buckets));
+ if (buckets == NULL) {
+ pr_err("failed to allocate memory for the buckets\n");
+ goto out;
+ }
+
line[0] = '\0';
while (!done) {
if (poll(&pollfd, 1, -1) < 0)
@@ -1030,7 +1168,7 @@ static int __cmd_latency(struct perf_ftrace *ftrace)
if (workload_exec_errno) {
const char *emsg = str_error_r(workload_exec_errno, buf, sizeof(buf));
pr_err("workload failed: %s\n", emsg);
- goto out;
+ goto out_free_buckets;
}
/* read remaining buffer contents */
@@ -1045,6 +1183,8 @@ static int __cmd_latency(struct perf_ftrace *ftrace)
display_histogram(ftrace, buckets);
+out_free_buckets:
+ free(buckets);
out:
close(trace_fd);
cleanup_func_latency(ftrace);
@@ -1288,17 +1428,20 @@ static int __cmd_profile(struct perf_ftrace *ftrace)
goto out;
}
+ if (init_tracing_instance() < 0)
+ goto out;
+
if (reset_tracing_files(ftrace) < 0) {
pr_err("failed to reset ftrace\n");
- goto out;
+ goto out_reset;
}
/* reset ftrace buffer */
if (write_tracing_file("trace", "0") < 0)
- goto out;
+ goto out_reset;
if (set_tracing_options(ftrace) < 0)
- return -1;
+ goto out_reset;
if (write_tracing_file("current_tracer", ftrace->tracer) < 0) {
pr_err("failed to set current_tracer to %s\n", ftrace->tracer);
@@ -1307,7 +1450,7 @@ static int __cmd_profile(struct perf_ftrace *ftrace)
setup_pager();
- trace_file = get_tracing_file("trace_pipe");
+ trace_file = get_tracing_instance_file("trace_pipe");
if (!trace_file) {
pr_err("failed to open trace_pipe\n");
goto out_reset;
@@ -1369,7 +1512,7 @@ out_free_line:
out_close_fd:
close(trace_fd);
out_reset:
- reset_tracing_files(ftrace);
+ exit_tracing_instance();
out:
return (done && !workload_exec_errno) ? 0 : -1;
}
@@ -1460,6 +1603,33 @@ static void delete_filter_func(struct list_head *head)
}
}
+static int parse_filter_event(const struct option *opt, const char *str,
+ int unset __maybe_unused)
+{
+ struct list_head *head = opt->value;
+ struct filter_entry *entry;
+ char *s, *p;
+ int ret = -ENOMEM;
+
+ s = strdup(str);
+ if (s == NULL)
+ return -ENOMEM;
+
+ while ((p = strsep(&s, ",")) != NULL) {
+ entry = malloc(sizeof(*entry) + strlen(p) + 1);
+ if (entry == NULL)
+ goto out;
+
+ strcpy(entry->name, p);
+ list_add_tail(&entry->list, head);
+ }
+ ret = 0;
+
+out:
+ free(s);
+ return ret;
+}
+
static int parse_buffer_size(const struct option *opt,
const char *str, int unset)
{
@@ -1518,6 +1688,10 @@ static int parse_graph_tracer_opts(const struct option *opt,
int ret;
struct perf_ftrace *ftrace = (struct perf_ftrace *) opt->value;
struct sublevel_option graph_tracer_opts[] = {
+ { .name = "args", .value_ptr = &ftrace->graph_args },
+ { .name = "retval", .value_ptr = &ftrace->graph_retval },
+ { .name = "retval-hex", .value_ptr = &ftrace->graph_retval_hex },
+ { .name = "retaddr", .value_ptr = &ftrace->graph_retaddr },
{ .name = "nosleep-time", .value_ptr = &ftrace->graph_nosleep_time },
{ .name = "noirqs", .value_ptr = &ftrace->graph_noirqs },
{ .name = "verbose", .value_ptr = &ftrace->graph_verbose },
@@ -1574,7 +1748,6 @@ int cmd_ftrace(int argc, const char **argv)
int (*cmd_func)(struct perf_ftrace *) = NULL;
struct perf_ftrace ftrace = {
.tracer = DEFAULT_TRACER,
- .target = { .uid = UINT_MAX, },
};
const struct option common_options[] = {
OPT_STRING('p', "pid", &ftrace.target.pid, "pid",
@@ -1610,7 +1783,7 @@ int cmd_ftrace(int argc, const char **argv)
OPT_CALLBACK('g', "nograph-funcs", &ftrace.nograph_funcs, "func",
"Set nograph filter on given functions", parse_filter_func),
OPT_CALLBACK(0, "graph-opts", &ftrace, "options",
- "Graph tracer options, available options: nosleep-time,noirqs,verbose,thresh=<n>,depth=<n>",
+ "Graph tracer options, available options: args,retval,retval-hex,retaddr,nosleep-time,noirqs,verbose,thresh=<n>,depth=<n>",
parse_graph_tracer_opts),
OPT_CALLBACK('m', "buffer-size", &ftrace.percpu_buffer_size, "size",
"Size of per cpu buffer, needs to use a B, K, M or G suffix.", parse_buffer_size),
@@ -1623,6 +1796,8 @@ int cmd_ftrace(int argc, const char **argv)
const struct option latency_options[] = {
OPT_CALLBACK('T', "trace-funcs", &ftrace.filters, "func",
"Show latency of given function", parse_filter_func),
+ OPT_CALLBACK('e', "events", &ftrace.event_pair, "event1,event2",
+ "Show latency between the two events", parse_filter_event),
#ifdef HAVE_BPF_SKEL
OPT_BOOLEAN('b', "use-bpf", &ftrace.target.use_bpf,
"Use BPF to measure function latency"),
@@ -1634,7 +1809,9 @@ int cmd_ftrace(int argc, const char **argv)
OPT_UINTEGER(0, "min-latency", &ftrace.min_latency,
"Minimum latency (1st bucket). Works only with --bucket-range."),
OPT_UINTEGER(0, "max-latency", &ftrace.max_latency,
- "Maximum latency (last bucket). Works only with --bucket-range and total buckets less than 22."),
+ "Maximum latency (last bucket). Works only with --bucket-range."),
+ OPT_BOOLEAN(0, "hide-empty", &ftrace.hide_empty,
+ "Hide empty buckets in the histogram"),
OPT_PARENT(common_options),
};
const struct option profile_options[] = {
@@ -1673,6 +1850,7 @@ int cmd_ftrace(int argc, const char **argv)
INIT_LIST_HEAD(&ftrace.notrace);
INIT_LIST_HEAD(&ftrace.graph_funcs);
INIT_LIST_HEAD(&ftrace.nograph_funcs);
+ INIT_LIST_HEAD(&ftrace.event_pair);
signal(SIGINT, sig_handler);
signal(SIGUSR1, sig_handler);
@@ -1727,9 +1905,24 @@ int cmd_ftrace(int argc, const char **argv)
cmd_func = __cmd_ftrace;
break;
case PERF_FTRACE_LATENCY:
- if (list_empty(&ftrace.filters)) {
- pr_err("Should provide a function to measure\n");
+ if (list_empty(&ftrace.filters) && list_empty(&ftrace.event_pair)) {
+ pr_err("Should provide a function or events to measure\n");
parse_options_usage(ftrace_usage, options, "T", 1);
+ parse_options_usage(NULL, options, "e", 1);
+ ret = -EINVAL;
+ goto out_delete_filters;
+ }
+ if (!list_empty(&ftrace.filters) && !list_empty(&ftrace.event_pair)) {
+ pr_err("Please specify either of function or events\n");
+ parse_options_usage(ftrace_usage, options, "T", 1);
+ parse_options_usage(NULL, options, "e", 1);
+ ret = -EINVAL;
+ goto out_delete_filters;
+ }
+ if (!list_empty(&ftrace.event_pair) && !ftrace.target.use_bpf) {
+ pr_err("Event processing needs BPF\n");
+ parse_options_usage(ftrace_usage, options, "b", 1);
+ parse_options_usage(NULL, options, "e", 1);
ret = -EINVAL;
goto out_delete_filters;
}
@@ -1751,10 +1944,25 @@ int cmd_ftrace(int argc, const char **argv)
ret = -EINVAL;
goto out_delete_filters;
}
- if (ftrace.bucket_range && !ftrace.max_latency) {
- /* default max latency should depend on bucket range and num_buckets */
- ftrace.max_latency = (NUM_BUCKET - 2) * ftrace.bucket_range +
- ftrace.min_latency;
+ if (ftrace.bucket_range && ftrace.max_latency &&
+ ftrace.max_latency < ftrace.min_latency + ftrace.bucket_range) {
+ /* we need at least 1 bucket excluding min and max buckets */
+ pr_err("--max-latency must be larger than min-latency + bucket-range\n");
+ parse_options_usage(ftrace_usage, options,
+ "max-latency", /*short_opt=*/false);
+ ret = -EINVAL;
+ goto out_delete_filters;
+ }
+ /* set default unless max_latency is set and valid */
+ ftrace.bucket_num = NUM_BUCKET;
+ if (ftrace.bucket_range) {
+ if (ftrace.max_latency)
+ ftrace.bucket_num = (ftrace.max_latency - ftrace.min_latency) /
+ ftrace.bucket_range + 2;
+ else
+ /* default max latency should depend on bucket range and num_buckets */
+ ftrace.max_latency = (NUM_BUCKET - 2) * ftrace.bucket_range +
+ ftrace.min_latency;
}
cmd_func = __cmd_latency;
break;
@@ -1805,6 +2013,7 @@ out_delete_filters:
delete_filter_func(&ftrace.notrace);
delete_filter_func(&ftrace.graph_funcs);
delete_filter_func(&ftrace.nograph_funcs);
+ delete_filter_func(&ftrace.event_pair);
return ret;
}
generated by cgit v1.2.3 (git 2.39.0) at 2025-08-26 07:50:43 +0300