When perf data is in a pipe, it reads each event separately using
read(2) syscall. This is a huge performance bottleneck when
processing large data like in perf inject. Also perf inject needs to
use write(2) syscall for the output.
So convert it to use buffer I/O functions in stdio library for pipe
data. This makes inject-build-id bench time drops from 20ms to 8ms.
$ perf bench internals inject-build-id
# Running 'internals/inject-build-id' benchmark:
Average build-id injection took: 8.074 msec (+- 0.013 msec)
Average time per event: 0.792 usec (+- 0.001 usec)
Average memory usage: 8328 KB (+- 0 KB)
Average build-id-all injection took: 5.490 msec (+- 0.008 msec)
Average time per event: 0.538 usec (+- 0.001 usec)
Average memory usage: 7563 KB (+- 0 KB)
This patch enables it just for perf inject when used with pipe (it's a
default behavior). Maybe we could do it for perf record and/or report
later..
Signed-off-by: Namhyung Kim <namhy...@kernel.org>
---
v2: check result of fdopen()
tools/perf/builtin-inject.c | 2 ++
tools/perf/util/data.c | 41 ++++++++++++++++++++++++++++++++++---
tools/perf/util/data.h | 11 +++++++++-
tools/perf/util/header.c | 8 ++++----
tools/perf/util/session.c | 7 ++++---
5 files changed, 58 insertions(+), 11 deletions(-)
diff --git a/tools/perf/builtin-inject.c b/tools/perf/builtin-inject.c
index 452a75fe68e5..14d6c88fed76 100644
--- a/tools/perf/builtin-inject.c
+++ b/tools/perf/builtin-inject.c
@@ -853,10 +853,12 @@ int cmd_inject(int argc, const char **argv)
.output = {
.path = "-",
.mode = PERF_DATA_MODE_WRITE,
+ .use_stdio = true,
},
};
struct perf_data data = {
.mode = PERF_DATA_MODE_READ,
+ .use_stdio = true,
};
int ret;
diff --git a/tools/perf/util/data.c b/tools/perf/util/data.c
index c47aa34fdc0a..05bbcb663c41 100644
--- a/tools/perf/util/data.c
+++ b/tools/perf/util/data.c
@@ -174,8 +174,21 @@ static bool check_pipe(struct perf_data *data)
is_pipe = true;
}
- if (is_pipe)
- data->file.fd = fd;
+ if (is_pipe) {
+ if (data->use_stdio) {
+ const char *mode;
+
+ mode = perf_data__is_read(data) ? "r" : "w";
+ data->file.fptr = fdopen(fd, mode);
+
+ if (data->file.fptr == NULL) {
+ data->file.fd = fd;
+ data->use_stdio = false;
+ }
+ } else {
+ data->file.fd = fd;
+ }
+ }
return data->is_pipe = is_pipe;
}
@@ -334,6 +347,9 @@ int perf_data__open(struct perf_data *data)
if (check_pipe(data))
return 0;
+ /* currently it allows stdio for pipe only */
+ data->use_stdio = false;
+
if (!data->path)
data->path = "perf.data";
@@ -353,7 +369,21 @@ void perf_data__close(struct perf_data *data)
perf_data__close_dir(data);
zfree(&data->file.path);
- close(data->file.fd);
+
+ if (data->use_stdio)
+ fclose(data->file.fptr);
+ else
+ close(data->file.fd);
+}
+
+ssize_t perf_data__read(struct perf_data *data, void *buf, size_t size)
+{
+ if (data->use_stdio) {
+ if (fread(buf, size, 1, data->file.fptr) == 1)
+ return size;
+ return feof(data->file.fptr) ? 0 : -1;
+ }
+ return readn(data->file.fd, buf, size);
}
ssize_t perf_data_file__write(struct perf_data_file *file,
@@ -365,6 +395,11 @@ ssize_t perf_data_file__write(struct perf_data_file *file,
ssize_t perf_data__write(struct perf_data *data,
void *buf, size_t size)
{
+ if (data->use_stdio) {
+ if (fwrite(buf, size, 1, data->file.fptr) == 1)
+ return size;
+ return -1;
+ }
return perf_data_file__write(&data->file, buf, size);
}
diff --git a/tools/perf/util/data.h b/tools/perf/util/data.h
index 75947ef6bc17..c563fcbb0288 100644
--- a/tools/perf/util/data.h
+++ b/tools/perf/util/data.h
@@ -2,6 +2,7 @@
#ifndef __PERF_DATA_H
#define __PERF_DATA_H
+#include <stdio.h>
#include <stdbool.h>
enum perf_data_mode {
@@ -16,7 +17,10 @@ enum perf_dir_version {
struct perf_data_file {
char *path;
- int fd;
+ union {
+ int fd;
+ FILE *fptr;
+ };
unsigned long size;
};
@@ -26,6 +30,7 @@ struct perf_data {
bool is_pipe;
bool is_dir;
bool force;
+ bool use_stdio;
enum perf_data_mode mode;
struct {
@@ -62,11 +67,15 @@ static inline bool perf_data__is_single_file(struct
perf_data *data)
static inline int perf_data__fd(struct perf_data *data)
{
+ if (data->use_stdio)
+ return fileno(data->file.fptr);
+
return data->file.fd;
}
int perf_data__open(struct perf_data *data);
void perf_data__close(struct perf_data *data);
+ssize_t perf_data__read(struct perf_data *data, void *buf, size_t size);
ssize_t perf_data__write(struct perf_data *data,
void *buf, size_t size);
ssize_t perf_data_file__write(struct perf_data_file *file,
diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index be850e9f8852..d9a70154426b 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -3652,7 +3652,8 @@ static int perf_file_section__process(struct
perf_file_section *section,
}
static int perf_file_header__read_pipe(struct perf_pipe_file_header *header,
- struct perf_header *ph, int fd,
+ struct perf_header *ph,
+ struct perf_data* data,
bool repipe)
{
struct feat_fd ff = {
@@ -3661,7 +3662,7 @@ static int perf_file_header__read_pipe(struct
perf_pipe_file_header *header,
};
ssize_t ret;
- ret = readn(fd, header, sizeof(*header));
+ ret = perf_data__read(data, header, sizeof(*header));
if (ret <= 0)
return -1;
@@ -3684,8 +3685,7 @@ static int perf_header__read_pipe(struct perf_session
*session)
struct perf_header *header = &session->header;
struct perf_pipe_file_header f_header;
- if (perf_file_header__read_pipe(&f_header, header,
- perf_data__fd(session->data),
+ if (perf_file_header__read_pipe(&f_header, header, session->data,
session->repipe) < 0) {
pr_debug("incompatible file format\n");
return -EINVAL;
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 7a5f03764702..f901a09a58e4 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -1923,7 +1923,6 @@ static int __perf_session__process_pipe_events(struct
perf_session *session)
{
struct ordered_events *oe = &session->ordered_events;
struct perf_tool *tool = session->tool;
- int fd = perf_data__fd(session->data);
union perf_event *event;
uint32_t size, cur_size = 0;
void *buf = NULL;
@@ -1943,7 +1942,8 @@ static int __perf_session__process_pipe_events(struct
perf_session *session)
ordered_events__set_copy_on_queue(oe, true);
more:
event = buf;
- err = readn(fd, event, sizeof(struct perf_event_header));
+ err = perf_data__read(session->data, event,
+ sizeof(struct perf_event_header));
if (err <= 0) {
if (err == 0)
goto done;
@@ -1975,7 +1975,8 @@ static int __perf_session__process_pipe_events(struct
perf_session *session)
p += sizeof(struct perf_event_header);
if (size - sizeof(struct perf_event_header)) {
- err = readn(fd, p, size - sizeof(struct perf_event_header));
+ err = perf_data__read(session->data, p,
+ size - sizeof(struct perf_event_header));
if (err <= 0) {
if (err == 0) {
pr_err("unexpected end of event stream\n");
--
2.29.1.341.ge80a0c044ae-goog
