Commit dc8d6ab2 authored by Arnaldo Carvalho de Melo's avatar Arnaldo Carvalho de Melo Committed by Ingo Molnar
Browse files

perf symbols: Use only --vmlinux if specified 



Found while analysing a perf.data file collected on an ARM
machine where an explicitely specified vmlinux was being
disregarded.

Reported-by: default avatarJamie Iles <jamie.iles@picochip.com>
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: <1263904574-30732-2-git-send-email-acme@infradead.org>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent f162f87a

tools/perf/util/symbol.c

+41 −26
Original line number Diff line number Diff line
@@ -1572,7 +1572,7 @@ static int dso__load_vmlinux(struct dso *self, struct map *map, 
		return -1;



	dso__set_loaded(self, map->type);

	err = dso__load_sym(self, map, session, self->long_name, fd, filter, 1, 0);

	err = dso__load_sym(self, map, session, vmlinux, fd, filter, 1, 0);

	close(fd);



	return err;
@@ -1584,6 +1584,26 @@ static int dso__load_kernel_sym(struct dso *self, struct map *map, 
	int err;

	const char *kallsyms_filename = NULL;

	char *kallsyms_allocated_filename = NULL;

	/*

	 * Step 1: if the user specified a vmlinux filename, use it and only

	 * it, reporting errors to the user if it cannot be used.

	 *

	 * For instance, try to analyse an ARM perf.data file _without_ a

	 * build-id, or if the user specifies the wrong path to the right

	 * vmlinux file, obviously we can't fallback to another vmlinux (a

	 * x86_86 one, on the machine where analysis is being performed, say),

	 * or worse, /proc/kallsyms.

	 *

	 * If the specified file _has_ a build-id and there is a build-id

	 * section in the perf.data file, we will still do the expected

	 * validation in dso__load_vmlinux and will bail out if they don't

	 * match.

	 */

	if (symbol_conf.vmlinux_name != NULL) {

		err = dso__load_vmlinux(self, map, session,

					symbol_conf.vmlinux_name, filter);

		goto out_try_fixup;

	}



	if (vmlinux_path != NULL) {

		int i;
@@ -1618,46 +1638,41 @@ static int dso__load_kernel_sym(struct dso *self, struct map *map, 
				goto do_kallsyms;

			}

		}



		/*

		 * Now look if we have it on the build-id cache in

		 * $HOME/.debug/[kernel.kallsyms].

		 */

		build_id__sprintf(self->build_id, sizeof(self->build_id),

				  sbuild_id);



		if (asprintf(&kallsyms_allocated_filename,

			     "%s/.debug/[kernel.kallsyms]/%s",

			     getenv("HOME"), sbuild_id) != -1) {

			     getenv("HOME"), sbuild_id) == -1)

			return -1;



		if (access(kallsyms_filename, F_OK)) {

				kallsyms_filename = kallsyms_allocated_filename;

				goto do_kallsyms;

			}

			free(kallsyms_allocated_filename);

			kallsyms_allocated_filename = NULL;

		}



		goto do_vmlinux;

			return -1;

		}



	if (self->long_name[0] == '[') {

		kallsyms_filename = kallsyms_allocated_filename;

	} else {

		/*

		 * Last resort, if we don't have a build-id and couldn't find

		 * any vmlinux file, try the running kernel kallsyms table.

		 */

		kallsyms_filename = "/proc/kallsyms";

		goto do_kallsyms;

	}



do_vmlinux:

	err = dso__load_vmlinux(self, map, session, self->long_name, filter);

	if (err <= 0) {

		if (self->has_build_id)

			return -1;



		pr_info("The file %s cannot be used, "

			"trying to use /proc/kallsyms...", self->long_name);

do_kallsyms:

	err = dso__load_kallsyms(self, kallsyms_filename, map, session, filter);

		if (err > 0 && kallsyms_filename == NULL)

                        dso__set_long_name(self, strdup("[kernel.kallsyms]"));

	free(kallsyms_allocated_filename);

	}



out_try_fixup:

	if (err > 0) {

out_fixup:

		if (kallsyms_filename == NULL)

			dso__set_long_name(self, strdup("[kernel.kallsyms]"));

		map__fixup_start(map);

		map__fixup_end(map);

	}