[PATCH V2 05/22] perf record: Add basic Instruction Tracing support

Adrian Hunter
2014-11-20T13:25:39Z

Amend the perf record tool to read the
Instruction Tracing mmap and synthesize
Instruction Tracing events.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
tools/perf/builtin-record.c | 99 ++++++++++++++++++++++++++++++++++++++-------
1 file changed, 85 insertions(+), 14 deletions(-)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 8648c6d..73c3d9b 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -27,6 +27,7 @@
#include "util/cpumap.h"
#include "util/thread_map.h"
#include "util/data.h"
+#include "util/itrace.h"

#include <unistd.h>
#include <sched.h>
@@ -38,6 +39,7 @@ struct record {
struct record_opts opts;
u64 bytes_written;
struct perf_data_file file;
+ struct itrace_record *itr;
struct perf_evlist *evlist;
struct perf_session *session;
const char *progname;
@@ -110,6 +112,43 @@ out:
return rc;
}

+static int record__process_itrace(struct perf_tool *tool,
+ union perf_event *event, void *data1,
+ size_t len1, void *data2, size_t len2)
+{
+ struct record *rec = container_of(tool, struct record, tool);
+ size_t padding;
+ u8 pad[8] = {0};
+
+ /* event.itrace.size includes padding, see __itrace_mmap__read() */
+ padding = (len1 + len2) & 7;
+ if (padding)
+ padding = 8 - padding;
+
+ record__write(rec, event, event->header.size);
+ record__write(rec, data1, len1);
+ record__write(rec, data2, len2);
+ record__write(rec, &pad, padding);
+
+ return 0;
+}
+
+static int record__itrace_mmap_read(struct record *rec,
+ struct itrace_mmap *mm)
+{
+ int ret;
+
+ ret = itrace_mmap__read(mm, rec->itr, &rec->tool,
+ record__process_itrace);
+ if (ret < 0)
+ return ret;
+
+ if (ret)
+ rec->samples++;
+
+ return 0;
+}
+
static volatile int done = 0;
static volatile int signr = -1;
static volatile int child_finished = 0;
@@ -168,13 +207,15 @@ try_again:
goto out;
}

- if (perf_evlist__mmap(evlist, opts->mmap_pages, false) < 0) {
+ if (perf_evlist__mmap_ex(evlist, opts->mmap_pages, false,
+ opts->itrace_mmap_pages, false) < 0) {
if (errno == EPERM) {
pr_err("Permission error mapping pages.\n"
"Consider increasing "
"/proc/sys/kernel/perf_event_mlock_kb,\n"
"or try again with a smaller value of -m/--mmap_pages.\n"
- "(current value: %u)\n", opts->mmap_pages);
+ "(current value: %u,%u)\n",
+ opts->mmap_pages, opts->itrace_mmap_pages);
rc = -errno;
} else {
pr_err("failed to mmap with %d (%s)\n", errno,
@@ -257,12 +298,20 @@ static int record__mmap_read_all(struct record *rec)
int rc = 0;

for (i = 0; i < rec->evlist->nr_mmaps; i++) {
+ struct itrace_mmap *mm = &rec->evlist->mmap[i].itrace_mmap;
+
if (rec->evlist->mmap[i].base) {
if (record__mmap_read(rec, i) != 0) {
rc = -1;
goto out;
}
}
+
+ if (mm->base &&
+ record__itrace_mmap_read(rec, mm) != 0) {
+ rc = -1;
+ goto out;
+ }
}

/*
@@ -292,6 +341,9 @@ static void record__init_features(struct record *rec)

if (!rec->opts.branch_stack)
perf_header__clear_feat(&session->header, HEADER_BRANCH_STACK);
+
+ if (!rec->opts.full_itrace)
+ perf_header__clear_feat(&session->header, HEADER_ITRACE);
}

static volatile int workload_exec_errno;
@@ -407,6 +459,13 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
}
}

+ if (rec->opts.full_itrace) {
+ err = perf_event__synthesize_itrace_info(rec->itr, tool,
+ session, process_synthesized_event);
+ if (err)
+ goto out_delete_session;
+ }
+
err = perf_event__synthesize_kernel_mmap(tool, process_synthesized_event,
machine);
if (err < 0)
@@ -505,16 +564,17 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
}

if (!quiet) {
- fprintf(stderr, "[ perf record: Woken up %ld times to write data ]\n", waking);
-
- /*
- * Approximate RIP event size: 24 bytes.
- */
- fprintf(stderr,
- "[ perf record: Captured and wrote %.3f MB %s (~%" PRIu64 " samples) ]\n",
- (double)rec->bytes_written / 1024.0 / 1024.0,
- file->path,
- rec->bytes_written / 24);
+ fprintf(stderr, "[ perf record: Woken up %ld times to write data ]\n",
+ waking);
+ fprintf(stderr, "[ perf record: Captured and wrote %.3f MB %s",
+ (double)rec->bytes_written / 1024.0 / 1024.0, file->path);
+ if (rec->opts.full_itrace) {
+ fprintf(stderr, " ]\n");
+ } else {
+ /* Approximate RIP event size: 24 bytes */
+ fprintf(stderr, " (~%" PRIu64 " samples) ]\n",
+ rec->bytes_written / 24);
+ }
}

out_child:
@@ -820,13 +880,18 @@ struct option *record_options = __record_options;

int cmd_record(int argc, const char **argv, const char *prefix __maybe_unused)
{
- int err = -ENOMEM;
+ int err;
struct record *rec = &record;
char errbuf[BUFSIZ];

+ rec->itr = itrace_record__init(&err);
+ if (err)
+ return err;
+
+ err = -ENOMEM;
rec->evlist = perf_evlist__new();
if (rec->evlist == NULL)
- return -ENOMEM;
+ goto out_itrace_free;

perf_config(perf_record_config, rec);

@@ -886,6 +951,10 @@ int cmd_record(int argc, const char **argv, const char *prefix __maybe_unused)
if (perf_evlist__create_maps(rec->evlist, &rec->opts.target) < 0)
usage_with_options(record_usage, record_options);

+ err = itrace_record__options(rec->itr, rec->evlist, &rec->opts);
+ if (err)
+ goto out_symbol_exit;
+
if (record_opts__config(&rec->opts)) {
err = -EINVAL;
goto out_symbol_exit;
@@ -895,5 +964,7 @@ int cmd_record(int argc, const char **argv, const char *prefix __maybe_unused)
out_symbol_exit:
perf_evlist__delete(rec->evlist);
symbol__exit();
+out_itrace_free:
+ itrace_record__free(rec->itr);
return err;
}
--
1.9.1