perf util: Save pid-cmdline mapping into tracing header

Current trace info data lacks the saved cmdline mapping which is needed
for pevent to find out the comm of a task.  Add this and bump up the
version number so that perf can determine its presence when reading.

This is mostly corresponding to trace.dat file version 6, but still
lacks 4 byte of number of cpus, and 10 bytes of type string - and I
think we don't need those anyway.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jeremy Eder <jeder@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>,
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
[ Change version test from == to >= ]
Link: http://lkml.kernel.org/n/tip-vaooqpxsikxbb3359p0corcb@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Namhyung Kim 2013-04-11 17:25:04 +09:00 committed by Arnaldo Carvalho de Melo
parent 0a87e7bc6c
commit cd4ceb6343
4 changed files with 84 additions and 3 deletions

View File

@ -42,7 +42,7 @@
#include "evsel.h"
#include "debug.h"
#define VERSION "0.5"
#define VERSION "0.6"
static int output_fd;
@ -379,6 +379,34 @@ out:
return err;
}
static int record_saved_cmdline(void)
{
unsigned int size;
char *path;
struct stat st;
int ret, err = 0;
path = get_tracing_file("saved_cmdlines");
if (!path) {
pr_debug("can't get tracing/saved_cmdline");
return -ENOMEM;
}
ret = stat(path, &st);
if (ret < 0) {
/* not found */
size = 0;
if (write(output_fd, &size, 8) != 8)
err = -EIO;
goto out;
}
err = record_file(path, 8);
out:
put_tracing_file(path);
return err;
}
static void
put_tracepoints_path(struct tracepoint_path *tps)
{
@ -539,6 +567,9 @@ struct tracing_data *tracing_data_get(struct list_head *pattrs,
if (err)
goto out;
err = record_ftrace_printk();
if (err)
goto out;
err = record_saved_cmdline();
out:
/*

View File

@ -160,6 +160,23 @@ void parse_ftrace_printk(struct pevent *pevent,
}
}
void parse_saved_cmdline(struct pevent *pevent,
char *file, unsigned int size __maybe_unused)
{
char *comm;
char *line;
char *next = NULL;
int pid;
line = strtok_r(file, "\n", &next);
while (line) {
sscanf(line, "%d %ms", &pid, &comm);
pevent_register_comm(pevent, comm, pid);
free(comm);
line = strtok_r(NULL, "\n", &next);
}
}
int parse_ftrace_file(struct pevent *pevent, char *buf, unsigned long size)
{
return pevent_parse_event(pevent, buf, size, "ftrace");

View File

@ -341,6 +341,31 @@ static int read_event_files(struct pevent *pevent)
return 0;
}
static int read_saved_cmdline(struct pevent *pevent)
{
unsigned long long size;
char *buf;
/* it can have 0 size */
size = read8(pevent);
if (!size)
return 0;
buf = malloc(size + 1);
if (buf == NULL)
return -1;
if (do_read(buf, size) < 0) {
free(buf);
return -1;
}
parse_saved_cmdline(pevent, buf, size);
free(buf);
return 0;
}
ssize_t trace_report(int fd, struct trace_event *tevent, bool __repipe)
{
char buf[BUFSIZ];
@ -379,10 +404,11 @@ ssize_t trace_report(int fd, struct trace_event *tevent, bool __repipe)
return -1;
if (show_version)
printf("version = %s\n", version);
free(version);
if (do_read(buf, 1) < 0)
if (do_read(buf, 1) < 0) {
free(version);
return -1;
}
file_bigendian = buf[0];
host_bigendian = bigendian();
@ -423,6 +449,11 @@ ssize_t trace_report(int fd, struct trace_event *tevent, bool __repipe)
err = read_ftrace_printk(pevent);
if (err)
goto out;
if (atof(version) >= 0.6) {
err = read_saved_cmdline(pevent);
if (err)
goto out;
}
size = trace_data_size;
repipe = false;
@ -438,5 +469,6 @@ ssize_t trace_report(int fd, struct trace_event *tevent, bool __repipe)
out:
if (pevent)
trace_event__cleanup(tevent);
free(version);
return size;
}

View File

@ -42,6 +42,7 @@ raw_field_value(struct event_format *event, const char *name, void *data);
void parse_proc_kallsyms(struct pevent *pevent, char *file, unsigned int size);
void parse_ftrace_printk(struct pevent *pevent, char *file, unsigned int size);
void parse_saved_cmdline(struct pevent *pevent, char *file, unsigned int size);
ssize_t trace_report(int fd, struct trace_event *tevent, bool repipe);