[PATCH 27/35] perf probe: Generalize probe event file open routine

From: Arnaldo Carvalho de Melo
Date: Mon Mar 06 2017 - 14:39:53 EST


From: "Naveen N. Rao" <naveen.n.rao@xxxxxxxxxxxxxxxxxx>

Generalize probe event file open routine into a generic function for opening
trace files.

Signed-off-by: Naveen N. Rao <naveen.n.rao@xxxxxxxxxxxxxxxxxx>
Acked-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Cc: Ananth N Mavinakayanahalli <ananth@xxxxxxxxxxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/b580465c7a4dcd5d3b40fdf8568e6be45d0a6333.1487849577.git.naveen.n.rao@xxxxxxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/util/probe-file.c | 20 +++++++++++---------
tools/perf/util/probe-file.h | 1 +
2 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c
index 436b64731f65..1a62daceb028 100644
--- a/tools/perf/util/probe-file.c
+++ b/tools/perf/util/probe-file.c
@@ -70,7 +70,7 @@ static void print_both_open_warning(int kerr, int uerr)
}
}

-static int open_probe_events(const char *trace_file, bool readwrite)
+int open_trace_file(const char *trace_file, bool readwrite)
{
char buf[PATH_MAX];
int ret;
@@ -92,12 +92,12 @@ static int open_probe_events(const char *trace_file, bool readwrite)

static int open_kprobe_events(bool readwrite)
{
- return open_probe_events("kprobe_events", readwrite);
+ return open_trace_file("kprobe_events", readwrite);
}

static int open_uprobe_events(bool readwrite)
{
- return open_probe_events("uprobe_events", readwrite);
+ return open_trace_file("uprobe_events", readwrite);
}

int probe_file__open(int flag)
@@ -899,6 +899,7 @@ bool probe_type_is_available(enum probe_type type)
size_t len = 0;
bool target_line = false;
bool ret = probe_type_table[type].avail;
+ int fd;

if (type >= PROBE_TYPE_END)
return false;
@@ -906,14 +907,16 @@ bool probe_type_is_available(enum probe_type type)
if (ret || probe_type_table[type].checked)
return ret;

- if (asprintf(&buf, "%s/README", tracing_path) < 0)
+ fd = open_trace_file("README", false);
+ if (fd < 0)
return ret;

- fp = fopen(buf, "r");
- if (!fp)
- goto end;
+ fp = fdopen(fd, "r");
+ if (!fp) {
+ close(fd);
+ return ret;
+ }

- zfree(&buf);
while (getline(&buf, &len, fp) > 0 && !ret) {
if (!target_line) {
target_line = !!strstr(buf, " type: ");
@@ -928,7 +931,6 @@ bool probe_type_is_available(enum probe_type type)
probe_type_table[type].avail = ret;

fclose(fp);
-end:
free(buf);

return ret;
diff --git a/tools/perf/util/probe-file.h b/tools/perf/util/probe-file.h
index eba44c3e9dca..a17a82eff8a0 100644
--- a/tools/perf/util/probe-file.h
+++ b/tools/perf/util/probe-file.h
@@ -35,6 +35,7 @@ enum probe_type {

/* probe-file.c depends on libelf */
#ifdef HAVE_LIBELF_SUPPORT
+int open_trace_file(const char *trace_file, bool readwrite);
int probe_file__open(int flag);
int probe_file__open_both(int *kfd, int *ufd, int flag);
struct strlist *probe_file__get_namelist(int fd);
--
2.9.3