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Grab a reference count to the map within the lock region and return this. Fix up locations that need a map__put following this. Signed-off-by: Ian Rogers Acked-by: Namhyung Kim --- tools/perf/arch/x86/tests/dwarf-unwind.c | 1 + tools/perf/tests/vmlinux-kallsyms.c | 5 ++--- tools/perf/util/bpf-event.c | 1 + tools/perf/util/event.c | 4 ++-- tools/perf/util/machine.c | 22 ++++++++-------------- tools/perf/util/maps.c | 17 ++++++++++------- tools/perf/util/symbol.c | 3 ++- 7 files changed, 26 insertions(+), 27 deletions(-) diff --git a/tools/perf/arch/x86/tests/dwarf-unwind.c b/tools/perf/arch/x86/tests/dwarf-unwind.c index 5bfec3345d59..c05c0a85dad4 100644 --- a/tools/perf/arch/x86/tests/dwarf-unwind.c +++ b/tools/perf/arch/x86/tests/dwarf-unwind.c @@ -34,6 +34,7 @@ static int sample_ustack(struct perf_sample *sample, } stack_size = map__end(map) - sp; + map__put(map); stack_size = stack_size > STACK_SIZE ? STACK_SIZE : stack_size; memcpy(buf, (void *) sp, stack_size); diff --git a/tools/perf/tests/vmlinux-kallsyms.c b/tools/perf/tests/vmlinux-kallsyms.c index 822f893e67d5..e808e6fc8f76 100644 --- a/tools/perf/tests/vmlinux-kallsyms.c +++ b/tools/perf/tests/vmlinux-kallsyms.c @@ -151,10 +151,8 @@ static int test__vmlinux_matches_kallsyms_cb2(struct map *map, void *data) u64 mem_end = map__unmap_ip(args->vmlinux_map, map__end(map)); pair = maps__find(args->kallsyms.kmaps, mem_start); - if (pair == NULL || map__priv(pair)) - return 0; - if (map__start(pair) == mem_start) { + if (pair != NULL && !map__priv(pair) && map__start(pair) == mem_start) { struct dso *dso = map__dso(map); if (!args->header_printed) { @@ -170,6 +168,7 @@ static int test__vmlinux_matches_kallsyms_cb2(struct map *map, void *data) pr_info(" %s\n", dso->name); map__set_priv(pair, 1); } + map__put(pair); return 0; } diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c index 3573e0b7ef3e..83709146a48a 100644 --- a/tools/perf/util/bpf-event.c +++ b/tools/perf/util/bpf-event.c @@ -63,6 +63,7 @@ static int machine__process_bpf_event_load(struct machine *machine, dso->bpf_prog.id = id; dso->bpf_prog.sub_id = i; dso->bpf_prog.env = env; + map__put(map); } } return 0; diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c index 68f45e9e63b6..198903157f9e 100644 --- a/tools/perf/util/event.c +++ b/tools/perf/util/event.c @@ -511,7 +511,7 @@ size_t perf_event__fprintf_text_poke(union perf_event *event, struct machine *ma struct addr_location al; addr_location__init(&al); - al.map = map__get(maps__find(machine__kernel_maps(machine), tp->addr)); + al.map = maps__find(machine__kernel_maps(machine), tp->addr); if (al.map && map__load(al.map) >= 0) { al.addr = map__map_ip(al.map, tp->addr); al.sym = map__find_symbol(al.map, al.addr); @@ -641,7 +641,7 @@ struct map *thread__find_map(struct thread *thread, u8 cpumode, u64 addr, return NULL; } al->maps = maps__get(maps); - al->map = map__get(maps__find(maps, al->addr)); + al->map = maps__find(maps, al->addr); if (al->map != NULL) { /* * Kernel maps might be changed when loading symbols so loading diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index b397a769006f..e8eb9f0b073f 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -896,7 +896,6 @@ static int machine__process_ksymbol_register(struct machine *machine, struct symbol *sym; struct dso *dso; struct map *map = maps__find(machine__kernel_maps(machine), event->ksymbol.addr); - bool put_map = false; int err = 0; if (!map) { @@ -913,12 +912,6 @@ static int machine__process_ksymbol_register(struct machine *machine, err = -ENOMEM; goto out; } - /* - * The inserted map has a get on it, we need to put to release - * the reference count here, but do it after all accesses are - * done. - */ - put_map = true; if (event->ksymbol.ksym_type == PERF_RECORD_KSYMBOL_TYPE_OOL) { dso->binary_type = DSO_BINARY_TYPE__OOL; dso->data.file_size = event->ksymbol.len; @@ -952,8 +945,7 @@ static int machine__process_ksymbol_register(struct machine *machine, } dso__insert_symbol(dso, sym); out: - if (put_map) - map__put(map); + map__put(map); return err; } @@ -977,7 +969,7 @@ static int machine__process_ksymbol_unregister(struct machine *machine, if (sym) dso__delete_symbol(dso, sym); } - + map__put(map); return 0; } @@ -1005,11 +997,11 @@ int machine__process_text_poke(struct machine *machine, union perf_event *event, perf_event__fprintf_text_poke(event, machine, stdout); if (!event->text_poke.new_len) - return 0; + goto out; if (cpumode != PERF_RECORD_MISC_KERNEL) { pr_debug("%s: unsupported cpumode - ignoring\n", __func__); - return 0; + goto out; } if (dso) { @@ -1032,7 +1024,8 @@ int machine__process_text_poke(struct machine *machine, union perf_event *event, pr_debug("Failed to find kernel text poke address map for %#" PRI_lx64 "\n", event->text_poke.addr); } - +out: + map__put(map); return 0; } @@ -1300,9 +1293,10 @@ static int machine__map_x86_64_entry_trampolines_cb(struct map *map, void *data) return 0; dest_map = maps__find(args->kmaps, map__pgoff(map)); - if (dest_map != map) + if (RC_CHK_ACCESS(dest_map) != RC_CHK_ACCESS(map)) map__set_pgoff(map, map__map_ip(dest_map, map__pgoff(map))); + map__put(dest_map); args->found = true; return 0; } diff --git a/tools/perf/util/maps.c b/tools/perf/util/maps.c index 45da1ec3630c..3336d540c577 100644 --- a/tools/perf/util/maps.c +++ b/tools/perf/util/maps.c @@ -500,15 +500,18 @@ void maps__remove_maps(struct maps *maps, bool (*cb)(struct map *map, void *data struct symbol *maps__find_symbol(struct maps *maps, u64 addr, struct map **mapp) { struct map *map = maps__find(maps, addr); + struct symbol *result = NULL; /* Ensure map is loaded before using map->map_ip */ if (map != NULL && map__load(map) >= 0) { - if (mapp != NULL) - *mapp = map; // TODO: map_put on else path when find returns a get. - return map__find_symbol(map, map__map_ip(map, addr)); - } + if (mapp) + *mapp = map; - return NULL; + result = map__find_symbol(map, map__map_ip(map, addr)); + if (!mapp) + map__put(map); + } + return result; } struct maps__find_symbol_by_name_args { @@ -552,7 +555,7 @@ int maps__find_ams(struct maps *maps, struct addr_map_symbol *ams) if (ams->addr < map__start(ams->ms.map) || ams->addr >= map__end(ams->ms.map)) { if (maps == NULL) return -1; - ams->ms.map = maps__find(maps, ams->addr); // TODO: map_get + ams->ms.map = maps__find(maps, ams->addr); if (ams->ms.map == NULL) return -1; } @@ -862,7 +865,7 @@ struct map *maps__find(struct maps *maps, u64 ip) sizeof(*mapp), map__addr_cmp); if (mapp) - result = *mapp; // map__get(*mapp); + result = map__get(*mapp); done = true; } up_read(maps__lock(maps)); diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index be212ba157dc..1710b89e207c 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -757,7 +757,6 @@ static int dso__load_all_kallsyms(struct dso *dso, const char *filename) static int maps__split_kallsyms_for_kcore(struct maps *kmaps, struct dso *dso) { - struct map *curr_map; struct symbol *pos; int count = 0; struct rb_root_cached old_root = dso->symbols; @@ -770,6 +769,7 @@ static int maps__split_kallsyms_for_kcore(struct maps *kmaps, struct dso *dso) *root = RB_ROOT_CACHED; while (next) { + struct map *curr_map; struct dso *curr_map_dso; char *module; @@ -796,6 +796,7 @@ static int maps__split_kallsyms_for_kcore(struct maps *kmaps, struct dso *dso) pos->end -= map__start(curr_map) - map__pgoff(curr_map); symbols__insert(&curr_map_dso->symbols, pos); ++count; + map__put(curr_map); } /* Symbols have been adjusted */