perf symbols: Do lazy symtab loading for the kernel & modules too
Arnaldo Carvalho de Melo [Fri, 20 Nov 2009 22:51:27 +0000 (20:51 -0200)]
Just like we do with the other DSOs. This also simplifies the
kernel_maps setup process, now all that the tools need to do is
to call kernel_maps__init and the maps for the modules and
kernel will be created, then, later, when
kernel_maps__find_symbol() is used, it will also call
maps__find_symbol that already checks if the symtab was loaded,
loading it if needed.

Now if one does 'perf top --hide_kernel_symbols' we won't pay
the price of loading the (many) symbols in /proc/kallsyms or
vmlinux.

Signed-off-by: Arnaldo 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: <1258757489-5978-4-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

tools/perf/builtin-annotate.c
tools/perf/builtin-report.c
tools/perf/builtin-top.c
tools/perf/util/data_map.c
tools/perf/util/event.h
tools/perf/util/header.c
tools/perf/util/map.c
tools/perf/util/symbol.c
tools/perf/util/symbol.h
tools/perf/util/thread.h

index b6da147..2031527 100644 (file)
@@ -157,7 +157,7 @@ process_sample_event(event_t *event, unsigned long offset, unsigned long head)
 
        if (event->header.misc & PERF_RECORD_MISC_KERNEL) {
                level = 'k';
-               sym = kernel_maps__find_symbol(ip, &map);
+               sym = kernel_maps__find_symbol(ip, &map, symbol_filter);
                dump_printf(" ...... dso: %s\n",
                            map ? map->dso->long_name : "<not found>");
        } else if (event->header.misc & PERF_RECORD_MISC_USER) {
@@ -637,9 +637,9 @@ static int __cmd_annotate(void)
                exit(0);
        }
 
-       if (load_kernel(symbol_filter, use_modules) < 0) {
-               perror("failed to load kernel symbols");
-               return EXIT_FAILURE;
+       if (kernel_maps__init(use_modules) < 0) {
+               pr_err("failed to create kernel maps for symbol resolution\b");
+               return -1;
        }
 
 remap:
index 0af4840..0d39e80 100644 (file)
@@ -449,7 +449,7 @@ got_map:
                 * trick of looking in the whole kernel symbol list.
                 */
                if ((long long)ip < 0)
-                       return kernel_maps__find_symbol(ip, mapp);
+                       return kernel_maps__find_symbol(ip, mapp, NULL);
        }
        dump_printf(" ...... dso: %s\n",
                    map ? map->dso->long_name : "<not found>");
@@ -496,7 +496,7 @@ static struct symbol **resolve_callchain(struct thread *thread, struct map *map,
                case PERF_CONTEXT_HV:
                        break;
                case PERF_CONTEXT_KERNEL:
-                       sym = kernel_maps__find_symbol(ip, &map);
+                       sym = kernel_maps__find_symbol(ip, &map, NULL);
                        break;
                default:
                        sym = resolve_symbol(thread, &map, &ip);
@@ -716,7 +716,7 @@ process_sample_event(event_t *event, unsigned long offset, unsigned long head)
 
        if (cpumode == PERF_RECORD_MISC_KERNEL) {
                level = 'k';
-               sym = kernel_maps__find_symbol(ip, &map);
+               sym = kernel_maps__find_symbol(ip, &map, NULL);
                dump_printf(" ...... dso: %s\n",
                            map ? map->dso->long_name : "<not found>");
        } else if (cpumode == PERF_RECORD_MISC_USER) {
index 48cc108..ea49c2e 100644 (file)
@@ -830,6 +830,8 @@ static void handle_keypress(int c)
                case 'q':
                case 'Q':
                        printf("exiting.\n");
+                       if (dump_symtab)
+                               dsos__fprintf(stderr);
                        exit(0);
                case 's':
                        prompt_symbol(&sym_filter_entry, "Enter details symbol");
@@ -946,30 +948,6 @@ static int symbol_filter(struct map *map, struct symbol *sym)
        return 0;
 }
 
-static int parse_symbols(void)
-{
-       struct dso *kernel = dsos__load_kernel();
-
-       if (kernel == NULL)
-               return -1;
-
-       if (dsos__load_modules() < 0)
-               pr_debug("Couldn't read the complete list of modules, "
-                        "continuing...\n");
-
-       if (dsos__load_modules_sym(symbol_filter) < 0)
-               pr_warning("Failed to read module symbols, continuing...\n");
-
-       if (dso__load_kernel_sym(kernel, symbol_filter, 1) <= 0)
-               pr_debug("Couldn't read the complete list of kernel symbols, "
-                        "continuing...\n");
-
-       if (dump_symtab)
-               dsos__fprintf(stderr);
-
-       return 0;
-}
-
 static void event__process_sample(const event_t *self, int counter)
 {
        u64 ip = self->ip.ip;
@@ -1012,7 +990,7 @@ static void event__process_sample(const event_t *self, int counter)
                if (hide_kernel_symbols)
                        return;
 
-               sym = kernel_maps__find_symbol(ip, &map);
+               sym = kernel_maps__find_symbol(ip, &map, symbol_filter);
                if (sym == NULL)
                        return;
                break;
@@ -1339,7 +1317,7 @@ static const struct option options[] = {
 
 int cmd_top(int argc, const char **argv, const char *prefix __used)
 {
-       int counter;
+       int counter, err;
 
        page_size = sysconf(_SC_PAGE_SIZE);
 
@@ -1363,10 +1341,11 @@ int cmd_top(int argc, const char **argv, const char *prefix __used)
        if (delay_secs < 1)
                delay_secs = 1;
 
-       parse_symbols();
+       err = kernel_maps__init(true);
+       if (err < 0)
+               return err;
        parse_source(sym_filter_entry);
 
-
        /*
         * User specified count overrides default frequency.
         */
index a444a26..e7b6c2b 100644 (file)
@@ -171,8 +171,8 @@ int mmap_dispatch_perf_file(struct perf_header **pheader,
                goto out_delete;
 
        err = -ENOMEM;
-       if (load_kernel(NULL, 1) < 0) {
-               pr_err("failed to load kernel symbols\n");
+       if (kernel_maps__init(true) < 0) {
+               pr_err("failed to setup the kernel maps to resolve symbols\n");
                goto out_delete;
        }
 
index 34c6fcb..f1e3926 100644 (file)
@@ -115,10 +115,13 @@ typedef int (*symbol_filter_t)(struct map *map, struct symbol *sym);
 void map__init(struct map *self, u64 start, u64 end, u64 pgoff,
               struct dso *dso);
 struct map *map__new(struct mmap_event *event, char *cwd, int cwdlen);
+void map__delete(struct map *self);
 struct map *map__clone(struct map *self);
 int map__overlap(struct map *l, struct map *r);
 size_t map__fprintf(struct map *self, FILE *fp);
 struct symbol *map__find_symbol(struct map *self, u64 ip, symbol_filter_t filter);
+void map__fixup_start(struct map *self);
+void map__fixup_end(struct map *self);
 
 int event__synthesize_thread(pid_t pid, int (*process)(event_t *event));
 void event__synthesize_threads(int (*process)(event_t *event));
index d5c81eb..ac3410b 100644 (file)
@@ -253,11 +253,11 @@ static int perf_header__adds_write(struct perf_header *self, int fd)
 
                buildid_sec = &feat_sec[idx++];
 
-               dsos__load_kernel();
                /*
-                * Read the list of loaded modules with its build_ids
+                * Read the kernel buildid nad the list of loaded modules with
+                * its build_ids:
                 */
-               dsos__load_modules();
+               kernel_maps__init(true);
 
                /* Write build-ids */
                buildid_sec->offset = lseek(fd, 0, SEEK_CUR);
index 94ca950..0941232 100644 (file)
@@ -75,6 +75,29 @@ out_delete:
        return NULL;
 }
 
+void map__delete(struct map *self)
+{
+       free(self);
+}
+
+void map__fixup_start(struct map *self)
+{
+       struct rb_node *nd = rb_first(&self->dso->syms);
+       if (nd != NULL) {
+               struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
+               self->start = sym->start;
+       }
+}
+
+void map__fixup_end(struct map *self)
+{
+       struct rb_node *nd = rb_last(&self->dso->syms);
+       if (nd != NULL) {
+               struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
+               self->end = sym->end;
+       }
+}
+
 #define DSO__DELETED "(deleted)"
 
 struct symbol *
index c324bdf..cb086cb 100644 (file)
@@ -27,6 +27,8 @@ static void dsos__add(struct dso *dso);
 static struct dso *dsos__find(const char *name);
 static struct map *map__new2(u64 start, struct dso *dso);
 static void kernel_maps__insert(struct map *map);
+static int dso__load_kernel_sym(struct dso *self, struct map *map,
+                               symbol_filter_t filter);
 unsigned int symbol__priv_size;
 
 static struct rb_root kernel_maps;
@@ -69,12 +71,6 @@ static void kernel_maps__fixup_end(void)
                curr = rb_entry(nd, struct map, rb_node);
                prev->end = curr->start - 1;
        }
-
-       nd = rb_last(&curr->dso->syms);
-       if (nd) {
-               struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
-               curr->end = sym->end;
-       }
 }
 
 static struct symbol *symbol__new(u64 start, u64 len, const char *name)
@@ -324,7 +320,7 @@ out_failure:
  * kernel range is broken in several maps, named [kernel].N, as we don't have
  * the original ELF section names vmlinux have.
  */
-static int kernel_maps__split_kallsyms(symbol_filter_t filter, int use_modules)
+static int kernel_maps__split_kallsyms(symbol_filter_t filter)
 {
        struct map *map = kernel_map;
        struct symbol *pos;
@@ -340,9 +336,6 @@ static int kernel_maps__split_kallsyms(symbol_filter_t filter, int use_modules)
 
                module = strchr(pos->name, '\t');
                if (module) {
-                       if (!use_modules)
-                               goto delete_symbol;
-
                        *module++ = '\0';
 
                        if (strcmp(map->dso->name, module)) {
@@ -382,7 +375,6 @@ static int kernel_maps__split_kallsyms(symbol_filter_t filter, int use_modules)
                }
 
                if (filter && filter(map, pos)) {
-delete_symbol:
                        rb_erase(&pos->rb_node, &kernel_map->dso->syms);
                        symbol__delete(pos);
                } else {
@@ -398,17 +390,18 @@ delete_symbol:
 }
 
 
-static int kernel_maps__load_kallsyms(symbol_filter_t filter, int use_modules)
+static int kernel_maps__load_kallsyms(symbol_filter_t filter)
 {
        if (kernel_maps__load_all_kallsyms())
                return -1;
 
        dso__fixup_sym_end(kernel_map->dso);
+       kernel_map->dso->origin = DSO__ORIG_KERNEL;
 
-       return kernel_maps__split_kallsyms(filter, use_modules);
+       return kernel_maps__split_kallsyms(filter);
 }
 
-static size_t kernel_maps__fprintf(FILE *fp)
+size_t kernel_maps__fprintf(FILE *fp)
 {
        size_t printed = fprintf(fp, "Kernel maps:\n");
        struct rb_node *nd;
@@ -1042,13 +1035,17 @@ 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);
+       char *name;
        u8 build_id[BUILD_ID_SIZE];
        int ret = -1;
        int fd;
 
        self->loaded = 1;
 
+       if (self->kernel)
+               return dso__load_kernel_sym(self, map, filter);
+
+       name = malloc(size);
        if (!name)
                return -1;
 
@@ -1139,7 +1136,8 @@ static void kernel_maps__insert(struct map *map)
        maps__insert(&kernel_maps, map);
 }
 
-struct symbol *kernel_maps__find_symbol(u64 ip, struct map **mapp)
+struct symbol *kernel_maps__find_symbol(u64 ip, struct map **mapp,
+                                       symbol_filter_t filter)
 {
        struct map *map = maps__find(&kernel_maps, ip);
 
@@ -1148,7 +1146,7 @@ struct symbol *kernel_maps__find_symbol(u64 ip, struct map **mapp)
 
        if (map) {
                ip = map->map_ip(map, ip);
-               return map->dso->find_symbol(map->dso, ip);
+               return map__find_symbol(map, ip, filter);
        }
 
        return NULL;
@@ -1168,28 +1166,9 @@ struct map *kernel_maps__find_by_dso_name(const char *name)
        return NULL;
 }
 
-static int dso__load_module_sym(struct dso *self, struct map *map,
-                               symbol_filter_t filter)
-{
-       int err = 0, fd = open(self->long_name, O_RDONLY);
-
-       self->loaded = 1;
-
-       if (fd < 0) {
-               pr_err("%s: cannot open %s\n", __func__, self->long_name);
-               return err;
-       }
-
-       err = dso__load_sym(self, map, self->long_name, fd, filter, 0, 1);
-       close(fd);
-
-       return err;
-}
-
-static int dsos__load_modules_sym_dir(char *dirname, symbol_filter_t filter)
+static int dsos__set_modules_path_dir(char *dirname)
 {
        struct dirent *dent;
-       int nr_symbols = 0, err;
        DIR *dir = opendir(dirname);
 
        if (!dir) {
@@ -1207,14 +1186,12 @@ static int dsos__load_modules_sym_dir(char *dirname, symbol_filter_t filter)
 
                        snprintf(path, sizeof(path), "%s/%s",
                                 dirname, dent->d_name);
-                       err = dsos__load_modules_sym_dir(path, filter);
-                       if (err < 0)
+                       if (dsos__set_modules_path_dir(path) < 0)
                                goto failure;
                } else {
                        char *dot = strrchr(dent->d_name, '.'),
                             dso_name[PATH_MAX];
                        struct map *map;
-                       struct rb_node *last;
                        char *long_name;
 
                        if (dot == NULL || strcmp(dot, ".ko"))
@@ -1234,36 +1211,16 @@ static int dsos__load_modules_sym_dir(char *dirname, symbol_filter_t filter)
                        if (long_name == NULL)
                                goto failure;
                        dso__set_long_name(map->dso, long_name);
-                       dso__set_basename(map->dso);
-
-                       err = dso__load_module_sym(map->dso, map, filter);
-                       if (err < 0)
-                               goto failure;
-                       last = rb_last(&map->dso->syms);
-                       if (last) {
-                               struct symbol *sym;
-                               /*
-                                * We do this here as well, even having the
-                                * symbol size found in the symtab because
-                                * misannotated ASM symbols may have the size
-                                * set to zero.
-                                */
-                               dso__fixup_sym_end(map->dso);
-
-                               sym = rb_entry(last, struct symbol, rb_node);
-                               map->end = map->start + sym->end;
-                       }
                }
-               nr_symbols += err;
        }
 
-       return nr_symbols;
+       return 0;
 failure:
        closedir(dir);
        return -1;
 }
 
-int dsos__load_modules_sym(symbol_filter_t filter)
+static int dsos__set_modules_path(void)
 {
        struct utsname uts;
        char modules_path[PATH_MAX];
@@ -1274,7 +1231,7 @@ int dsos__load_modules_sym(symbol_filter_t filter)
        snprintf(modules_path, sizeof(modules_path), "/lib/modules/%s/kernel",
                 uts.release);
 
-       return dsos__load_modules_sym_dir(modules_path, filter);
+       return dsos__set_modules_path_dir(modules_path);
 }
 
 /*
@@ -1296,7 +1253,7 @@ static struct map *map__new2(u64 start, struct dso *dso)
        return self;
 }
 
-int dsos__load_modules(void)
+static int kernel_maps__create_module_maps(void)
 {
        char *line = NULL;
        size_t n;
@@ -1360,7 +1317,13 @@ int dsos__load_modules(void)
        free(line);
        fclose(file);
 
-       return 0;
+       /*
+        * Now that we have all sorted out, just set the ->end of all
+        * maps:
+        */
+       kernel_maps__fixup_end();
+
+       return dsos__set_modules_path();
 
 out_delete_line:
        free(line);
@@ -1385,40 +1348,17 @@ static int dso__load_vmlinux(struct dso *self, struct map *map,
        return err;
 }
 
-int dso__load_kernel_sym(struct dso *self, symbol_filter_t filter,
-                        int use_modules)
+static int dso__load_kernel_sym(struct dso *self, struct map *map,
+                               symbol_filter_t filter)
 {
-       int err;
+       int err = dso__load_vmlinux(self, map, self->name, filter);
 
-       kernel_map = map__new2(0, self);
-       if (kernel_map == NULL)
-               return -1;
-
-       kernel_map->map_ip = kernel_map->unmap_ip = identity__map_ip;
-
-       err = dso__load_vmlinux(self, kernel_map, self->name, filter);
        if (err <= 0)
-               err = kernel_maps__load_kallsyms(filter, use_modules);
+               err = kernel_maps__load_kallsyms(filter);
 
        if (err > 0) {
-               struct rb_node *node = rb_first(&self->syms);
-               struct symbol *sym = rb_entry(node, struct symbol, rb_node);
-
-               kernel_map->start = sym->start;
-               node = rb_last(&self->syms);
-               sym = rb_entry(node, struct symbol, rb_node);
-               kernel_map->end = sym->end;
-
-               self->origin = DSO__ORIG_KERNEL;
-               kernel_maps__insert(kernel_map);
-               /*
-                * Now that we have all sorted out, just set the ->end of all
-                * maps:
-                */
-               kernel_maps__fixup_end();
-
-               if (verbose)
-                       kernel_maps__fprintf(stderr);
+               map__fixup_start(map);
+               map__fixup_end(map);
        }
 
        return err;
@@ -1479,46 +1419,51 @@ size_t dsos__fprintf_buildid(FILE *fp)
        return ret;
 }
 
-struct dso *dsos__load_kernel(void)
+static int kernel_maps__create_kernel_map(void)
 {
        struct dso *kernel = dso__new(vmlinux_name);
 
        if (kernel == NULL)
-               return NULL;
+               return -1;
+
+       kernel_map = map__new2(0, kernel);
+       if (kernel_map == NULL)
+               goto out_delete_kernel_dso;
+
+       kernel_map->map_ip = kernel_map->unmap_ip = identity__map_ip;
 
        kernel->short_name = "[kernel]";
+       kernel->kernel = 1;
        vdso = dso__new("[vdso]");
-       if (!vdso)
-               return NULL;
+       if (vdso == NULL)
+               goto out_delete_kernel_map;
 
        if (sysfs__read_build_id("/sys/kernel/notes", kernel->build_id,
                                 sizeof(kernel->build_id)) == 0)
                kernel->has_build_id = true;
 
+       kernel_maps__insert(kernel_map);
        dsos__add(kernel);
        dsos__add(vdso);
 
-       return kernel;
+       return 0;
+
+out_delete_kernel_map:
+       map__delete(kernel_map);
+       kernel_map = NULL;
+out_delete_kernel_dso:
+       dso__delete(kernel);
+       return -1;
 }
 
-int load_kernel(symbol_filter_t filter, bool use_modules)
+int kernel_maps__init(bool use_modules)
 {
-       struct dso *kernel = dsos__load_kernel();
-
-       if (kernel == NULL)
+       if (kernel_maps__create_kernel_map() < 0)
                return -1;
 
-       if (use_modules) {
-               if (dsos__load_modules() < 0)
-                       pr_warning("Failed to load list of modules in use, "
-                                  "continuing...\n");
-               else if (dsos__load_modules_sym(filter) < 0)
-                       pr_warning("Failed to read module symbols, "
-                                  "continuing...\n");
-       }
-
-       if (dso__load_kernel_sym(kernel, filter, use_modules) < 0)
-               pr_warning("Failed to read kernel symbols, continuing...\n");
+       if (use_modules && kernel_maps__create_module_maps() < 0)
+               pr_warning("Failed to load list of modules in use, "
+                          "continuing...\n");
 
        return 0;
 }
index 3d9d346..7a12904 100644 (file)
@@ -64,6 +64,7 @@ struct dso {
        u8               slen_calculated:1;
        u8               loaded:1;
        u8               has_build_id:1;
+       u8               kernel:1;
        unsigned char    origin;
        u8               build_id[BUILD_ID_SIZE];
        u16              long_name_len;
@@ -77,12 +78,8 @@ void dso__delete(struct dso *self);
 
 struct symbol *dso__find_symbol(struct dso *self, u64 ip);
 
-int dsos__load_modules(void);
-int dsos__load_modules_sym(symbol_filter_t filter);
 struct dso *dsos__findnew(const char *name);
 int dso__load(struct dso *self, struct map *map, symbol_filter_t filter);
-int dso__load_kernel_sym(struct dso *self, symbol_filter_t filter,
-                        int use_modules);
 void dsos__fprintf(FILE *fp);
 size_t dsos__fprintf_buildid(FILE *fp);
 
@@ -96,8 +93,8 @@ int sysfs__read_build_id(const char *filename, void *bf, size_t size);
 bool dsos__read_build_ids(void);
 int build_id__sprintf(u8 *self, int len, char *bf);
 
-struct dso *dsos__load_kernel(void);
-int load_kernel(symbol_filter_t filter, bool use_modules);
+int kernel_maps__init(bool use_modules);
+size_t kernel_maps__fprintf(FILE *fp);
 
 void symbol__init(unsigned int priv_size);
 
index 53addd7..e4b8d43 100644 (file)
@@ -26,7 +26,8 @@ size_t threads__fprintf(FILE *fp);
 void maps__insert(struct rb_root *maps, struct map *map);
 struct map *maps__find(struct rb_root *maps, u64 ip);
 
-struct symbol *kernel_maps__find_symbol(const u64 ip, struct map **mapp);
+struct symbol *kernel_maps__find_symbol(const u64 ip, struct map **mapp,
+                                       symbol_filter_t filter);
 struct map *kernel_maps__find_by_dso_name(const char *name);
 
 static inline struct map *thread__find_map(struct thread *self, u64 ip)