Commit d3379ab9 authored by Arnaldo Carvalho de Melo's avatar Arnaldo Carvalho de Melo Committed by Ingo Molnar
Browse files

perf symbols: Fix comparision of build_ids 



When we read the build_id from the DSO name to then index into
/usr/lib/debug/.buildid/DSO_BUILD_ID[0:2]/DSO_BUILD_ID[2:], we
were jumping directly to the comparision with the buildid we
already have in dso->build_id (that came from the perf.data
build_id section, collected at perf record time)
unconditionally, even if we didn't had recorded it, and
furthermore, comparing a formatted buildid with a rawbuildid, yikes.

Fix it by deleting the dso__read_build_id() function, that was
really misdesigned anyway, and do the necessary checks and
correct comparison of raw buildids.

Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1258582853-8579-1-git-send-email-acme@infradead.org>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent b269876c

tools/perf/util/symbol.c

+16 −36
Original line number Diff line number Diff line
@@ -962,25 +962,6 @@ out: 
	return err;

}



static char *dso__read_build_id(struct dso *self)

{

	int len;

	char *build_id = NULL;

	unsigned char rawbf[BUILD_ID_SIZE];



	len = filename__read_build_id(self->long_name, rawbf, sizeof(rawbf));

	if (len < 0)

		goto out;



	build_id = malloc(len * 2 + 1);

	if (build_id == NULL)

		goto out;



	build_id__sprintf(rawbf, len, build_id);

out:

	return build_id;

}



char dso__symtab_origin(const struct dso *self)

{

	static const char origin[] = {
@@ -1001,7 +982,8 @@ char dso__symtab_origin(const struct dso *self) 
int dso__load(struct dso *self, struct map *map, symbol_filter_t filter)

{

	int size = PATH_MAX;

	char *name = malloc(size), *build_id = NULL;

	char *name = malloc(size);

	u8 build_id[BUILD_ID_SIZE];

	int ret = -1;

	int fd;
@@ -1023,8 +1005,6 @@ int dso__load(struct dso *self, struct map *map, symbol_filter_t filter) 


more:

	do {

		int berr = 0;



		self->origin++;

		switch (self->origin) {

		case DSO__ORIG_FEDORA:
@@ -1036,12 +1016,18 @@ more: 
				 self->long_name);

			break;

		case DSO__ORIG_BUILDID:

			build_id = dso__read_build_id(self);

			if (build_id != NULL) {

			if (filename__read_build_id(self->long_name, build_id,

						    sizeof(build_id))) {

				char build_id_hex[BUILD_ID_SIZE * 2 + 1];



				build_id__sprintf(build_id, sizeof(build_id),

						  build_id_hex);

				snprintf(name, size,

					 "/usr/lib/debug/.build-id/%.2s/%s.debug",

					build_id, build_id + 2);

					build_id_hex, build_id_hex + 2);

				if (self->has_build_id)

					goto compare_build_id;

				break;

			}

			self->origin++;

			/* Fall thru */
@@ -1054,18 +1040,12 @@ more: 
		}



		if (self->has_build_id) {

			bool match;

			build_id = malloc(BUILD_ID_SIZE);

			if (build_id == NULL)

			if (filename__read_build_id(name, build_id,

						    sizeof(build_id)) < 0)

				goto more;

			berr = filename__read_build_id(name, build_id,

						       BUILD_ID_SIZE);

compare_build_id:

			match = berr > 0 && memcmp(build_id, self->build_id,

						   sizeof(self->build_id)) == 0;

			free(build_id);

			build_id = NULL;

			if (!match)

			if (memcmp(build_id, self->build_id,

				   sizeof(self->build_id)) != 0)

				goto more;

		}

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