From: Namhyung Kim <namhyung....@lge.com>
The ftrace show subcommand is for viewing recorded ftrace files. It
enters perf.data.dir directory and open perf.header file to find out
necessary information. And then read out per-cpu trace records using
kbuffer helper and print them to stdout in time order.
It only shows its basic form so function graph doesn't show duration/
overhead and no leaf entry handling is provided yet. Maybe it can be
handled by a proper plugin in the libtraceevent.
Cc: Frederic Weisbecker <fweis...@gmail.com>
Cc: Steven Rostedt <rost...@goodmis.org>
Signed-off-by: Namhyung Kim <namhy...@kernel.org>
---
tools/perf/builtin-ftrace.c | 427 +++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 425 insertions(+), 2 deletions(-)
diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c
index 4392e08d545a..86e730dde23a 100644
--- a/tools/perf/builtin-ftrace.c
+++ b/tools/perf/builtin-ftrace.c
@@ -13,6 +13,7 @@
#include <signal.h>
#include <fcntl.h>
#include <dirent.h>
+#include <sys/mman.h>
#include "util/debug.h"
#include "util/parse-options.h"
@@ -21,6 +22,8 @@
#include "util/thread_map.h"
#include "util/cpumap.h"
#include "util/trace-event.h"
+#include "../lib/traceevent/kbuffer.h"
+#include "../lib/traceevent/event-parse.h"
#define DEFAULT_TRACER "function_graph"
@@ -31,6 +34,7 @@ struct perf_ftrace {
struct perf_target target;
const char *tracer;
const char *dirname;
+ struct pevent *pevent;
};
static bool done;
@@ -786,6 +790,371 @@ out_reset:
}
static int
+function_handler(struct trace_seq *s, struct pevent_record *record,
+ struct event_format *event, void *context __maybe_unused)
+{
+ struct pevent *pevent = event->pevent;
+ unsigned long long function;
+ const char *func;
+
+ if (pevent_get_field_val(s, event, "ip", record, &function, 1))
+ return trace_seq_putc(s, '!');
+
+ func = pevent_find_function(pevent, function);
+ if (func)
+ trace_seq_printf(s, "%s <-- ", func);
+ else
+ trace_seq_printf(s, "0x%llx", function);
+
+ if (pevent_get_field_val(s, event, "parent_ip", record, &function, 1))
+ return trace_seq_putc(s, '!');
+
+ func = pevent_find_function(pevent, function);
+ if (func)
+ trace_seq_printf(s, "%s", func);
+ else
+ trace_seq_printf(s, "0x%llx", function);
+
+ trace_seq_putc(s, '\n');
+ return 0;
+}
+
+#define TRACE_GRAPH_INDENT 2
+
+static int
+fgraph_ent_handler(struct trace_seq *s, struct pevent_record *record,
+ struct event_format *event, void *context __maybe_unused)
+{
+ unsigned long long depth;
+ unsigned long long val;
+ const char *func;
+ int i;
+
+ if (pevent_get_field_val(s, event, "depth", record, &depth, 1))
+ return trace_seq_putc(s, '!');
+
+ /* Function */
+ for (i = 0; i < (int)(depth * TRACE_GRAPH_INDENT); i++)
+ trace_seq_putc(s, ' ');
+
+ if (pevent_get_field_val(s, event, "func", record, &val, 1))
+ return trace_seq_putc(s, '!');
+
+ func = pevent_find_function(event->pevent, val);
+
+ if (func)
+ trace_seq_printf(s, "%s() {", func);
+ else
+ trace_seq_printf(s, "%llx() {", val);
+
+ trace_seq_putc(s, '\n');
+ return 0;
+}
+
+static int
+fgraph_ret_handler(struct trace_seq *s, struct pevent_record *record,
+ struct event_format *event, void *context __maybe_unused)
+{
+ unsigned long long depth;
+ int i;
+
+ if (pevent_get_field_val(s, event, "depth", record, &depth, 1))
+ return trace_seq_putc(s, '!');
+
+ /* Function */
+ for (i = 0; i < (int)(depth * TRACE_GRAPH_INDENT); i++)
+ trace_seq_putc(s, ' ');
+
+ trace_seq_puts(s, "}\n");
+ return 0;
+}
+
+struct perf_ftrace_report {
+ struct perf_ftrace *ftrace;
+ struct perf_tool tool;
+};
+
+struct ftrace_report_arg {
+ struct list_head node;
+ struct pevent_record *record;
+ struct kbuffer *kbuf;
+ void *map;
+ int cpu;
+ int fd;
+ off_t offset;
+ off_t size;
+};
+
+static LIST_HEAD(ftrace_cpu_buffers);
+
+static int process_sample_show(struct perf_tool *tool,
+ union perf_event * event __maybe_unused,
+ struct perf_sample *sample,
+ struct perf_evsel *evsel __maybe_unused,
+ struct machine *machine __maybe_unused)
+{
+ struct perf_ftrace *ftrace;
+ struct perf_ftrace_report *show;
+ struct ftrace_report_arg *fra;
+ struct stat statbuf;
+ enum kbuffer_long_size long_size;
+ enum kbuffer_endian endian;
+ char buf[PATH_MAX];
+
+ show = container_of(tool, struct perf_ftrace_report, tool);
+ ftrace = show->ftrace;
+
+ fra = zalloc(sizeof(*fra));
+ if (fra == NULL)
+ return -1;
+
+ fra->cpu = sample->cpu;
+
+ scnprintf(buf, sizeof(buf), "%s.dir/trace-cpu%d.buf",
+ ftrace->dirname, fra->cpu);
+
+ fra->fd = open(buf, O_RDONLY);
+ if (fra->fd < 0)
+ goto out;
+
+ if (fstat(fra->fd, &statbuf) < 0)
+ goto out_close;
+
+ fra->size = statbuf.st_size;
+ if (fra->size == 0) {
+ /* skip zero-size buffers */
+ free(fra);
+ return 0;
+ }
+
+ /*
+ * FIXME: What if pevent->page_size is smaller than current page size?
+ */
+ fra->map = mmap(NULL, pevent_get_page_size(ftrace->pevent),
+ PROT_READ, MAP_PRIVATE, fra->fd, fra->offset);
+ if (fra->map == MAP_FAILED)
+ goto out_close;
+
+ fra->offset = 0;
+
+ if (pevent_is_file_bigendian(ftrace->pevent))
+ endian = KBUFFER_ENDIAN_BIG;
+ else
+ endian = KBUFFER_ENDIAN_LITTLE;
+
+ if (pevent_get_long_size(ftrace->pevent) == 8)
+ long_size = KBUFFER_LSIZE_8;
+ else
+ long_size = KBUFFER_LSIZE_4;
+
+ fra->kbuf = kbuffer_alloc(long_size, endian);
+ if (fra->kbuf == NULL)
+ goto out_unmap;
+
+ if (ftrace->pevent->old_format)
+ kbuffer_set_old_format(fra->kbuf);
+
+ kbuffer_load_subbuffer(fra->kbuf, fra->map);
+
+ pr_debug2("setup kbuffer for cpu%d\n", fra->cpu);
+ list_add_tail(&fra->node, &ftrace_cpu_buffers);
+ return 0;
+
+out_unmap:
+ munmap(fra->map, pevent_get_page_size(ftrace->pevent));
+out_close:
+ close(fra->fd);
+out:
+ free(fra);
+ return -1;
+}
+
+static struct pevent_record *
+get_next_ftrace_event_record(struct perf_ftrace *ftrace,
+ struct ftrace_report_arg *fra)
+{
+ struct pevent_record *record;
+ unsigned long long ts;
+ void *data;
+
+retry:
+ data = kbuffer_read_event(fra->kbuf, &ts);
+ if (data) {
+ record = zalloc(sizeof(*record));
+ if (record == NULL) {
+ pr_err("memory allocation failure\n");
+ return NULL;
+ }
+
+ record->ts = ts;
+ record->cpu = fra->cpu;
+ record->data = data;
+ record->size = kbuffer_event_size(fra->kbuf);
+ record->record_size = kbuffer_curr_size(fra->kbuf);
+ record->offset = kbuffer_curr_offset(fra->kbuf);
+ record->missed_events = kbuffer_missed_events(fra->kbuf);
+ record->ref_count = 1;
+
+ kbuffer_next_event(fra->kbuf, NULL);
+ return record;
+ }
+
+ munmap(fra->map, pevent_get_page_size(ftrace->pevent));
+ fra->map = NULL;
+
+ fra->offset += pevent_get_page_size(ftrace->pevent);
+ if (fra->offset >= fra->size) {
+ /* EOF */
+ return NULL;
+ }
+
+ fra->map = mmap(NULL, pevent_get_page_size(ftrace->pevent),
+ PROT_READ, MAP_PRIVATE, fra->fd, fra->offset);
+ if (fra->map == MAP_FAILED) {
+ pr_err("memory mapping failed\n");
+ return NULL;
+ }
+
+ kbuffer_load_subbuffer(fra->kbuf, fra->map);
+
+ goto retry;
+}
+
+static struct pevent_record *
+get_ftrace_event_record(struct perf_ftrace *ftrace,
+ struct ftrace_report_arg *fra)
+{
+ if (fra->record == NULL)
+ fra->record = get_next_ftrace_event_record(ftrace, fra);
+
+ return fra->record;
+}
+
+static struct pevent_record *get_ordered_record(struct perf_ftrace *ftrace)
+{
+ struct ftrace_report_arg *fra = NULL;
+ struct ftrace_report_arg *tmp;
+ struct pevent_record *record;
+ unsigned long long min_ts = LLONG_MAX;
+
+ list_for_each_entry(tmp, &ftrace_cpu_buffers, node) {
+ if (perf_target__has_cpu(&ftrace->target)) {
+ int i;
+ bool found = false;
+
+ for (i = 0; i < cpu_map__nr(ftrace->evlist->cpus); i++)
{
+ if (tmp->cpu == ftrace->evlist->cpus->map[i]) {
+ found = true;
+ break;
+ }
+ }
+ if (!found)
+ continue;
+ }
+
+ record = get_ftrace_event_record(ftrace, tmp);
+ if (record && record->ts < min_ts) {
+ min_ts = record->ts;
+ fra = tmp;
+ }
+ }
+
+ if (fra) {
+ record = fra->record;
+ fra->record = NULL;
+ return record;
+ }
+ return NULL;
+}
+
+static void free_ftrace_report_args(struct perf_ftrace *ftrace)
+{
+ struct ftrace_report_arg *fra, *tmp;
+
+ list_for_each_entry_safe(fra, tmp, &ftrace_cpu_buffers, node) {
+ list_del(&fra->node);
+
+ /* don't care about the errors */
+ munmap(fra->map, pevent_get_page_size(ftrace->pevent));
+ kbuffer_free(fra->kbuf);
+ free(fra->record);
+ close(fra->fd);
+ free(fra);
+ }
+}
+
+static int do_ftrace_show(struct perf_ftrace *ftrace)
+{
+ int ret = 0;
+ char buf[PATH_MAX];
+ struct perf_session *session;
+ struct pevent_record *record;
+ struct trace_seq seq;
+ struct perf_ftrace_report show = {
+ .ftrace = ftrace,
+ .tool = {
+ .sample = process_sample_show,
+ },
+ };
+
+ scnprintf(buf, sizeof(buf), "%s.dir/perf.header", ftrace->dirname);
+
+ session = perf_session__new(buf, O_RDONLY, false, false, &show.tool);
+ if (session == NULL) {
+ pr_err("failed to create a session\n");
+ return -1;
+ }
+
+ ftrace->pevent = session->pevent;
+
+ pevent_register_event_handler(ftrace->pevent, -1,
+ "ftrace", "function",
+ function_handler, NULL);
+ pevent_register_event_handler(ftrace->pevent, -1,
+ "ftrace", "funcgraph_entry",
+ fgraph_ent_handler, NULL);
+ pevent_register_event_handler(ftrace->pevent, -1,
+ "ftrace", "funcgraph_exit",
+ fgraph_ret_handler, NULL);
+
+ if (perf_session__process_events(session, &show.tool) < 0) {
+ pr_err("failed to process events\n");
+ ret = -1;
+ goto out;
+ }
+
+ trace_seq_init(&seq);
+
+ record = get_ordered_record(ftrace);
+ while (record) {
+ int type;
+ struct event_format *event;
+
+ type = pevent_data_type(ftrace->pevent, record);
+ event = pevent_find_event(ftrace->pevent, type);
+ if (!event) {
+ pr_warning("no event found for type %d", type);
+ continue;
+ }
+
+ pevent_print_event(ftrace->pevent, &seq, record);
+ trace_seq_do_printf(&seq);
+
+ trace_seq_reset(&seq);
+
+ free(record);
+ record = get_ordered_record(ftrace);
+ }
+
+ trace_seq_destroy(&seq);
+
+out:
+ free_ftrace_report_args(ftrace);
+ perf_session__delete(session);
+ return ret;
+}
+
+static int
__cmd_ftrace_live(struct perf_ftrace *ftrace, int argc, const char **argv)
{
int ret = -1;
@@ -916,6 +1285,58 @@ out:
return ret;
}
+static int
+__cmd_ftrace_show(struct perf_ftrace *ftrace, int argc, const char **argv)
+{
+ int ret = -1;
+ const char * const show_usage[] = {
+ "perf ftrace show [<options>]",
+ NULL
+ };
+ const struct option show_options[] = {
+ OPT_STRING('i', "input", &ftrace->dirname, "dirname",
+ "input directory name to use (default: perf.data)"),
+ OPT_INCR('v', "verbose", &verbose,
+ "be more verbose"),
+ OPT_STRING('C', "cpu", &ftrace->target.cpu_list, "cpu",
+ "list of cpus to monitor"),
+ OPT_END()
+ };
+
+ argc = parse_options(argc, argv, show_options, show_usage,
+ PARSE_OPT_STOP_AT_NON_OPTION);
+ if (argc)
+ usage_with_options(show_usage, show_options);
+
+ ret = perf_target__validate(&ftrace->target);
+ if (ret) {
+ char errbuf[512];
+
+ perf_target__strerror(&ftrace->target, ret, errbuf, 512);
+ pr_err("%s\n", errbuf);
+ return -EINVAL;
+ }
+
+ ftrace->evlist = perf_evlist__new();
+ if (ftrace->evlist == NULL)
+ return -ENOMEM;
+
+ ret = perf_evlist__create_maps(ftrace->evlist, &ftrace->target);
+ if (ret < 0)
+ goto out;
+
+ if (ftrace->dirname == NULL)
+ ftrace->dirname = DEFAULT_DIRNAME;
+
+ ret = do_ftrace_show(ftrace);
+
+ perf_evlist__delete_maps(ftrace->evlist);
+out:
+ perf_evlist__delete(ftrace->evlist);
+
+ return ret;
+}
+
int cmd_ftrace(int argc, const char **argv, const char *prefix __maybe_unused)
{
int ret;
@@ -923,8 +1344,8 @@ int cmd_ftrace(int argc, const char **argv, const char
*prefix __maybe_unused)
.target = { .uid = UINT_MAX, },
};
const char * const ftrace_usage[] = {
- "perf ftrace {live|record} [<options>] [<command>]",
- "perf ftrace {live|record} [<options>] -- <command>
[<options>]",
+ "perf ftrace {live|record|show} [<options>] [<command>]",
+ "perf ftrace {live|record|show} [<options>] -- <command>
[<options>]",
NULL
};
const struct option ftrace_options[] = {
@@ -945,6 +1366,8 @@ int cmd_ftrace(int argc, const char **argv, const char
*prefix __maybe_unused)
ret = __cmd_ftrace_live(&ftrace, argc, argv);
} else if (strncmp(argv[0], "rec", 3) == 0) {
ret = __cmd_ftrace_record(&ftrace, argc, argv);
+ } else if (strcmp(argv[0], "show") == 0) {
+ ret = __cmd_ftrace_show(&ftrace, argc, argv);
} else {
usage_with_options(ftrace_usage, ftrace_options);
}
--
1.7.11.7
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