1 files changed, 53 insertions, 58 deletions

diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c
index 51cf82cf1882..bbed90e5d9bb 100644
--- a/tools/perf/util/dso.c
+++ b/tools/perf/util/dso.c
@@ -189,28 +189,34 @@ int dso__read_binary_type_filename(const struct dso *dso,
 	return ret;
 }
 
+enum {
+	COMP_ID__NONE = 0,
+};
+
 static const struct {
 	const char *fmt;
 	int (*decompress)(const char *input, int output);
+	bool (*is_compressed)(const char *input);
 } compressions[] = {
+	[COMP_ID__NONE] = { .fmt = NULL, },
 #ifdef HAVE_ZLIB_SUPPORT
-	{ "gz", gzip_decompress_to_file },
+	{ "gz", gzip_decompress_to_file, gzip_is_compressed },
 #endif
 #ifdef HAVE_LZMA_SUPPORT
-	{ "xz", lzma_decompress_to_file },
+	{ "xz", lzma_decompress_to_file, lzma_is_compressed },
 #endif
-	{ NULL, NULL },
+	{ NULL, NULL, NULL },
 };
 
-bool is_supported_compression(const char *ext)
+static int is_supported_compression(const char *ext)
 {
 	unsigned i;
 
-	for (i = 0; compressions[i].fmt; i++) {
+	for (i = 1; compressions[i].fmt; i++) {
 		if (!strcmp(ext, compressions[i].fmt))
-			return true;
+			return i;
 	}
-	return false;
+	return COMP_ID__NONE;
 }
 
 bool is_kernel_module(const char *pathname, int cpumode)
@@ -239,80 +245,73 @@ bool is_kernel_module(const char *pathname, int cpumode)
 	return m.kmod;
 }
 
-bool decompress_to_file(const char *ext, const char *filename, int output_fd)
-{
-	unsigned i;
-
-	for (i = 0; compressions[i].fmt; i++) {
-		if (!strcmp(ext, compressions[i].fmt))
-			return !compressions[i].decompress(filename,
-							   output_fd);
-	}
-	return false;
-}
-
 bool dso__needs_decompress(struct dso *dso)
 {
 	return dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP ||
 		dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE_COMP;
 }
 
-static int decompress_kmodule(struct dso *dso, const char *name, char *tmpbuf)
+static int decompress_kmodule(struct dso *dso, const char *name,
+			      char *pathname, size_t len)
 {
+	char tmpbuf[] = KMOD_DECOMP_NAME;
 	int fd = -1;
-	struct kmod_path m;
 
 	if (!dso__needs_decompress(dso))
 		return -1;
 
-	if (kmod_path__parse_ext(&m, dso->long_name))
+	if (dso->comp == COMP_ID__NONE)
 		return -1;
 
-	if (!m.comp)
-		goto out;
+	/*
+	 * We have proper compression id for DSO and yet the file
+	 * behind the 'name' can still be plain uncompressed object.
+	 *
+	 * The reason is behind the logic we open the DSO object files,
+	 * when we try all possible 'debug' objects until we find the
+	 * data. So even if the DSO is represented by 'krava.xz' module,
+	 * we can end up here opening ~/.debug/....23432432/debug' file
+	 * which is not compressed.
+	 *
+	 * To keep this transparent, we detect this and return the file
+	 * descriptor to the uncompressed file.
+	 */
+	if (!compressions[dso->comp].is_compressed(name))
+		return open(name, O_RDONLY);
 
 	fd = mkstemp(tmpbuf);
 	if (fd < 0) {
 		dso->load_errno = errno;
-		goto out;
+		return -1;
 	}
 
-	if (!decompress_to_file(m.ext, name, fd)) {
+	if (compressions[dso->comp].decompress(name, fd)) {
 		dso->load_errno = DSO_LOAD_ERRNO__DECOMPRESSION_FAILURE;
 		close(fd);
 		fd = -1;
 	}
 
-out:
-	free(m.ext);
+	if (!pathname || (fd < 0))
+		unlink(tmpbuf);
+
+	if (pathname && (fd >= 0))
+		strncpy(pathname, tmpbuf, len);
+
 	return fd;
 }
 
 int dso__decompress_kmodule_fd(struct dso *dso, const char *name)
 {
-	char tmpbuf[] = KMOD_DECOMP_NAME;
-	int fd;
-
-	fd = decompress_kmodule(dso, name, tmpbuf);
-	unlink(tmpbuf);
-	return fd;
+	return decompress_kmodule(dso, name, NULL, 0);
 }
 
 int dso__decompress_kmodule_path(struct dso *dso, const char *name,
 				 char *pathname, size_t len)
 {
-	char tmpbuf[] = KMOD_DECOMP_NAME;
-	int fd;
+	int fd = decompress_kmodule(dso, name, pathname, len);
 
-	fd = decompress_kmodule(dso, name, tmpbuf);
-	if (fd < 0) {
-		unlink(tmpbuf);
-		return -1;
-	}
-
-	strncpy(pathname, tmpbuf, len);
 	close(fd);
-	return 0;
+	return fd >= 0 ? 0 : -1;
 }
 
 /*
@@ -332,7 +331,7 @@ int dso__decompress_kmodule_path(struct dso *dso, const char *name,
  * Returns 0 if there's no strdup error, -ENOMEM otherwise.
  */
 int __kmod_path__parse(struct kmod_path *m, const char *path,
-		       bool alloc_name, bool alloc_ext)
+		       bool alloc_name)
 {
 	const char *name = strrchr(path, '/');
 	const char *ext  = strrchr(path, '.');
@@ -372,10 +371,9 @@ int __kmod_path__parse(struct kmod_path *m, const char *path,
 		return 0;
 	}
 
-	if (is_supported_compression(ext + 1)) {
-		m->comp = true;
+	m->comp = is_supported_compression(ext + 1);
+	if (m->comp > COMP_ID__NONE)
 		ext -= 3;
-	}
 
 	/* Check .ko extension only if there's enough name left. */
 	if (ext > name)
@@ -393,14 +391,6 @@ int __kmod_path__parse(struct kmod_path *m, const char *path,
 		strxfrchar(m->name, '-', '_');
 	}
 
-	if (alloc_ext && m->comp) {
-		m->ext = strdup(ext + 4);
-		if (!m->ext) {
-			free((void *) m->name);
-			return -ENOMEM;
-		}
-	}
-
 	return 0;
 }
 
@@ -413,8 +403,10 @@ void dso__set_module_info(struct dso *dso, struct kmod_path *m,
 		dso->symtab_type = DSO_BINARY_TYPE__GUEST_KMODULE;
 
 	/* _KMODULE_COMP should be next to _KMODULE */
-	if (m->kmod && m->comp)
+	if (m->kmod && m->comp) {
 		dso->symtab_type++;
+		dso->comp = m->comp;
+	}
 
 	dso__set_short_name(dso, strdup(m->name), true);
 }
@@ -468,6 +460,7 @@ static int __open_dso(struct dso *dso, struct machine *machine)
 	int fd = -EINVAL;
 	char *root_dir = (char *)"";
 	char *name = malloc(PATH_MAX);
+	bool decomp = false;
 
 	if (!name)
 		return -ENOMEM;
@@ -491,12 +484,13 @@ static int __open_dso(struct dso *dso, struct machine *machine)
 			goto out;
 		}
 
+		decomp = true;
 		strcpy(name, newpath);
 	}
 
 	fd = do_open(name);
 
-	if (dso__needs_decompress(dso))
+	if (decomp)
 		unlink(name);
 
 out:
@@ -1218,6 +1212,7 @@ struct dso *dso__new(const char *name)
 		dso->a2l_fails = 1;
 		dso->kernel = DSO_TYPE_USER;
 		dso->needs_swap = DSO_SWAP__UNSET;
+		dso->comp = COMP_ID__NONE;
 		RB_CLEAR_NODE(&dso->rb_node);
 		dso->root = NULL;
 		INIT_LIST_HEAD(&dso->node);