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Commit 22a9f41b authored by Arnaldo Carvalho de Melo's avatar Arnaldo Carvalho de Melo
Browse files

perf tools: Use readdir() instead of deprecated readdir_r() 

The readdir() function is thread safe as long as just one thread uses a
DIR, which is the case when parsing tracepoint event definitions, to
avoid breaking the build with glibc-2.23.90 (upcoming 2.24), use it
instead of readdir_r().

See: http://man7.org/linux/man-pages/man3/readdir.3.html

"However, in modern implementations (including the glibc implementation),
concurrent calls to readdir() that specify different directory streams
are thread-safe.  In cases where multiple threads must read from the
same directory stream, using readdir() with external synchronization is
still preferable to the use of the deprecated readdir_r(3) function."

Noticed while building on a Fedora Rawhide docker container.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-wddn49r6bz6wq4ee3dxbl7lo@git.kernel.org


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 7839b9f3

tools/perf/util/parse-events.c

+30 −30
Original line number Diff line number Diff line
@@ -138,11 +138,11 @@ struct event_symbol event_symbols_sw[PERF_COUNT_SW_MAX] = { 
#define PERF_EVENT_TYPE(config)		__PERF_EVENT_FIELD(config, TYPE)

#define PERF_EVENT_ID(config)		__PERF_EVENT_FIELD(config, EVENT)



#define for_each_subsystem(sys_dir, sys_dirent, sys_next)	       \

	while (!readdir_r(sys_dir, &sys_dirent, &sys_next) && sys_next)	       \

	if (sys_dirent.d_type == DT_DIR &&				       \

	   (strcmp(sys_dirent.d_name, ".")) &&				       \

	   (strcmp(sys_dirent.d_name, "..")))

#define for_each_subsystem(sys_dir, sys_dirent)			\

	while ((sys_dirent = readdir(sys_dir)) != NULL)		\

		if (sys_dirent->d_type == DT_DIR &&		\

		    (strcmp(sys_dirent->d_name, ".")) &&	\

		    (strcmp(sys_dirent->d_name, "..")))



static int tp_event_has_id(struct dirent *sys_dir, struct dirent *evt_dir)

{
@@ -159,12 +159,12 @@ static int tp_event_has_id(struct dirent *sys_dir, struct dirent *evt_dir) 
	return 0;

}



#define for_each_event(sys_dirent, evt_dir, evt_dirent, evt_next)	       \

	while (!readdir_r(evt_dir, &evt_dirent, &evt_next) && evt_next)        \

	if (evt_dirent.d_type == DT_DIR &&				       \

	   (strcmp(evt_dirent.d_name, ".")) &&				       \

	   (strcmp(evt_dirent.d_name, "..")) &&				       \

	   (!tp_event_has_id(&sys_dirent, &evt_dirent)))

#define for_each_event(sys_dirent, evt_dir, evt_dirent)		\

	while ((evt_dirent = readdir(evt_dir)) != NULL)		\

		if (evt_dirent->d_type == DT_DIR &&		\

		    (strcmp(evt_dirent->d_name, ".")) &&	\

		    (strcmp(evt_dirent->d_name, "..")) &&	\

		    (!tp_event_has_id(sys_dirent, evt_dirent)))



#define MAX_EVENT_LENGTH 512
@@ -173,7 +173,7 @@ struct tracepoint_path *tracepoint_id_to_path(u64 config) 
{

	struct tracepoint_path *path = NULL;

	DIR *sys_dir, *evt_dir;

	struct dirent *sys_next, *evt_next, sys_dirent, evt_dirent;

	struct dirent *sys_dirent, *evt_dirent;

	char id_buf[24];

	int fd;

	u64 id;
@@ -184,18 +184,18 @@ struct tracepoint_path *tracepoint_id_to_path(u64 config) 
	if (!sys_dir)

		return NULL;



	for_each_subsystem(sys_dir, sys_dirent, sys_next) {

	for_each_subsystem(sys_dir, sys_dirent) {



		snprintf(dir_path, MAXPATHLEN, "%s/%s", tracing_events_path,

			 sys_dirent.d_name);

			 sys_dirent->d_name);

		evt_dir = opendir(dir_path);

		if (!evt_dir)

			continue;



		for_each_event(sys_dirent, evt_dir, evt_dirent, evt_next) {

		for_each_event(sys_dirent, evt_dir, evt_dirent) {



			snprintf(evt_path, MAXPATHLEN, "%s/%s/id", dir_path,

				 evt_dirent.d_name);

				 evt_dirent->d_name);

			fd = open(evt_path, O_RDONLY);

			if (fd < 0)

				continue;
@@ -220,9 +220,9 @@ struct tracepoint_path *tracepoint_id_to_path(u64 config) 
					free(path);

					return NULL;

				}

				strncpy(path->system, sys_dirent.d_name,

				strncpy(path->system, sys_dirent->d_name,

					MAX_EVENT_LENGTH);

				strncpy(path->name, evt_dirent.d_name,

				strncpy(path->name, evt_dirent->d_name,

					MAX_EVENT_LENGTH);

				return path;

			}
@@ -1812,7 +1812,7 @@ void print_tracepoint_events(const char *subsys_glob, const char *event_glob, 
			     bool name_only)

{

	DIR *sys_dir, *evt_dir;

	struct dirent *sys_next, *evt_next, sys_dirent, evt_dirent;

	struct dirent *sys_dirent, *evt_dirent;

	char evt_path[MAXPATHLEN];

	char dir_path[MAXPATHLEN];

	char **evt_list = NULL;
@@ -1830,20 +1830,20 @@ void print_tracepoint_events(const char *subsys_glob, const char *event_glob, 
			goto out_close_sys_dir;

	}



	for_each_subsystem(sys_dir, sys_dirent, sys_next) {

	for_each_subsystem(sys_dir, sys_dirent) {

		if (subsys_glob != NULL &&

		    !strglobmatch(sys_dirent.d_name, subsys_glob))

		    !strglobmatch(sys_dirent->d_name, subsys_glob))

			continue;



		snprintf(dir_path, MAXPATHLEN, "%s/%s", tracing_events_path,

			 sys_dirent.d_name);

			 sys_dirent->d_name);

		evt_dir = opendir(dir_path);

		if (!evt_dir)

			continue;



		for_each_event(sys_dirent, evt_dir, evt_dirent, evt_next) {

		for_each_event(sys_dirent, evt_dir, evt_dirent) {

			if (event_glob != NULL &&

			    !strglobmatch(evt_dirent.d_name, event_glob))

			    !strglobmatch(evt_dirent->d_name, event_glob))

				continue;



			if (!evt_num_known) {
@@ -1852,7 +1852,7 @@ void print_tracepoint_events(const char *subsys_glob, const char *event_glob, 
			}



			snprintf(evt_path, MAXPATHLEN, "%s:%s",

				 sys_dirent.d_name, evt_dirent.d_name);

				 sys_dirent->d_name, evt_dirent->d_name);



			evt_list[evt_i] = strdup(evt_path);

			if (evt_list[evt_i] == NULL)
@@ -1905,7 +1905,7 @@ void print_tracepoint_events(const char *subsys_glob, const char *event_glob, 
int is_valid_tracepoint(const char *event_string)

{

	DIR *sys_dir, *evt_dir;

	struct dirent *sys_next, *evt_next, sys_dirent, evt_dirent;

	struct dirent *sys_dirent, *evt_dirent;

	char evt_path[MAXPATHLEN];

	char dir_path[MAXPATHLEN];
@@ -1913,17 +1913,17 @@ int is_valid_tracepoint(const char *event_string) 
	if (!sys_dir)

		return 0;



	for_each_subsystem(sys_dir, sys_dirent, sys_next) {

	for_each_subsystem(sys_dir, sys_dirent) {



		snprintf(dir_path, MAXPATHLEN, "%s/%s", tracing_events_path,

			 sys_dirent.d_name);

			 sys_dirent->d_name);

		evt_dir = opendir(dir_path);

		if (!evt_dir)

			continue;



		for_each_event(sys_dirent, evt_dir, evt_dirent, evt_next) {

		for_each_event(sys_dirent, evt_dir, evt_dirent) {

			snprintf(evt_path, MAXPATHLEN, "%s:%s",

				 sys_dirent.d_name, evt_dirent.d_name);

				 sys_dirent->d_name, evt_dirent->d_name);

			if (!strcmp(evt_path, event_string)) {

				closedir(evt_dir);

				closedir(sys_dir);