Em Sat, Nov 14, 2020 at 09:55:34PM +0100, Jiri Olsa escreveu:
> On Fri, Oct 30, 2020 at 02:47:42PM +0900, Namhyung Kim wrote:
> > 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 <[email protected]>
> 
> Acked-by: Jiri Olsa <[email protected]>

Thanks, tested and applied.

- Arnaldo
 
> thanks,
> jirka
> 
> > ---
> > 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
> > 
> 

-- 

- Arnaldo

Reply via email to