[PATCH 11/47] perf tools: Use argv style storage for cmdline feature data

Jiri Olsa
2015-07-21T12:43:07Z

We will reuse argv style data in following change to display
counters header showing monitored command line.

Link: http://lkml.kernel.org/n/tip-qu64zmm5zbpbkuybusnkg4gl@git.kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
tools/perf/util/header.c | 35 ++++++++++++++++++++---------------
tools/perf/util/header.h | 1 +
tools/perf/util/session.c | 1 +
3 files changed, 22 insertions(+), 15 deletions(-)

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 03ace57a800c..179b2bdd157d 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -923,17 +923,13 @@ static void print_cmdline(struct perf_header *ph, int fd __maybe_unused,
FILE *fp)
{
int nr, i;
- char *str;

nr = ph->env.nr_cmdline;
- str = ph->env.cmdline;

fprintf(fp, "# cmdline : ");

- for (i = 0; i < nr; i++) {
- fprintf(fp, "%s ", str);
- str += strlen(str) + 1;
- }
+ for (i = 0; i < nr; i++)
+ fprintf(fp, "%s ", ph->env.cmdline_argv[i]);
fputc('\n', fp);
}

@@ -1541,14 +1537,13 @@ process_event_desc(struct perf_file_section *section __maybe_unused,
return 0;
}

-static int process_cmdline(struct perf_file_section *section __maybe_unused,
+static int process_cmdline(struct perf_file_section *section,
struct perf_header *ph, int fd,
void *data __maybe_unused)
{
ssize_t ret;
- char *str;
- u32 nr, i;
- struct strbuf sb;
+ char *str, *cmdline = NULL, **argv = NULL;
+ u32 nr, i, len = 0;

ret = readn(fd, &nr, sizeof(nr));
if (ret != sizeof(nr))
@@ -1558,22 +1553,32 @@ static int process_cmdline(struct perf_file_section *section __maybe_unused,
nr = bswap_32(nr);

ph->env.nr_cmdline = nr;
- strbuf_init(&sb, 128);
+
+ cmdline = zalloc(section->size + nr + 1);
+ if (!cmdline)
+ return -1;
+
+ argv = zalloc(sizeof(char *) * (nr + 1));
+ if (!argv)
+ goto error;

for (i = 0; i < nr; i++) {
str = do_read_string(fd, ph);
if (!str)
goto error;

- /* include a NULL character at the end */
- strbuf_add(&sb, str, strlen(str) + 1);
+ argv[i] = cmdline + len;
+ memcpy(argv[i], str, strlen(str) + 1);
+ len += strlen(str) + 1;
free(str);
}
- ph->env.cmdline = strbuf_detach(&sb, NULL);
+ ph->env.cmdline = cmdline;
+ ph->env.cmdline_argv = (const char **) argv;
return 0;

error:
- strbuf_release(&sb);
+ free(argv);
+ free(cmdline);
return -1;
}

diff --git a/tools/perf/util/header.h b/tools/perf/util/header.h
index d4d57962c591..9b53b6525ce8 100644
--- a/tools/perf/util/header.h
+++ b/tools/perf/util/header.h
@@ -84,6 +84,7 @@ struct perf_session_env {
int nr_pmu_mappings;
int nr_groups;
char *cmdline;
+ const char **cmdline_argv;
char *sibling_cores;
char *sibling_threads;
char *numa_nodes;
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index ed9dc2555ec7..fb1d525ca3d0 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -180,6 +180,7 @@ static void perf_session_env__delete(struct perf_session_env *env)
zfree(&env->cpuid);

zfree(&env->cmdline);
+ zfree(&env->cmdline_argv);
zfree(&env->sibling_cores);
zfree(&env->sibling_threads);
zfree(&env->numa_nodes);
--
2.4.3