Re: [PATCH 3/9] perf tools: Pass build_id object to filename__read_build_id

From: Ian Rogers
Date: Thu Oct 01 2020 - 01:17:42 EST


On Wed, Sep 30, 2020 at 10:15 AM Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
>
> Passing build_id object to filename__read_build_id function,
> so it can populate the size of the build_id object.
>
> Changing filename__read_build_id code for both elf/non-elf
> code.
>
> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>

Acked-by: Ian Rogers <irogers@xxxxxxxxxx>

Thanks,
Ian

> ---
> tools/perf/builtin-buildid-cache.c | 25 +++++++++++-----------
> tools/perf/builtin-inject.c | 3 +--
> tools/perf/tests/pe-file-parsing.c | 10 ++++-----
> tools/perf/tests/sdt.c | 6 +++---
> tools/perf/util/build-id.c | 8 +++----
> tools/perf/util/dsos.c | 3 +--
> tools/perf/util/symbol-elf.c | 16 ++++++++------
> tools/perf/util/symbol-minimal.c | 34 +++++++++++++++++-------------
> tools/perf/util/symbol.c | 6 +++---
> tools/perf/util/symbol.h | 3 ++-
> 10 files changed, 59 insertions(+), 55 deletions(-)
>
> diff --git a/tools/perf/builtin-buildid-cache.c b/tools/perf/builtin-buildid-cache.c
> index a523c629f321..c3cb168d546d 100644
> --- a/tools/perf/builtin-buildid-cache.c
> +++ b/tools/perf/builtin-buildid-cache.c
> @@ -174,19 +174,19 @@ static int build_id_cache__add_kcore(const char *filename, bool force)
> static int build_id_cache__add_file(const char *filename, struct nsinfo *nsi)
> {
> char sbuild_id[SBUILD_ID_SIZE];
> - u8 build_id[BUILD_ID_SIZE];
> + struct build_id bid;
> int err;
> struct nscookie nsc;
>
> nsinfo__mountns_enter(nsi, &nsc);
> - err = filename__read_build_id(filename, &build_id, sizeof(build_id));
> + err = filename__read_build_id(filename, &bid);
> nsinfo__mountns_exit(&nsc);
> if (err < 0) {
> pr_debug("Couldn't read a build-id in %s\n", filename);
> return -1;
> }
>
> - build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
> + build_id__sprintf(bid.data, sizeof(bid.data), sbuild_id);
> err = build_id_cache__add_s(sbuild_id, filename, nsi,
> false, false);
> pr_debug("Adding %s %s: %s\n", sbuild_id, filename,
> @@ -196,21 +196,21 @@ static int build_id_cache__add_file(const char *filename, struct nsinfo *nsi)
>
> static int build_id_cache__remove_file(const char *filename, struct nsinfo *nsi)
> {
> - u8 build_id[BUILD_ID_SIZE];
> char sbuild_id[SBUILD_ID_SIZE];
> + struct build_id bid;
> struct nscookie nsc;
>
> int err;
>
> nsinfo__mountns_enter(nsi, &nsc);
> - err = filename__read_build_id(filename, &build_id, sizeof(build_id));
> + err = filename__read_build_id(filename, &bid);
> nsinfo__mountns_exit(&nsc);
> if (err < 0) {
> pr_debug("Couldn't read a build-id in %s\n", filename);
> return -1;
> }
>
> - build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
> + build_id__sprintf(bid.data, sizeof(bid.data), sbuild_id);
> err = build_id_cache__remove_s(sbuild_id);
> pr_debug("Removing %s %s: %s\n", sbuild_id, filename,
> err ? "FAIL" : "Ok");
> @@ -274,17 +274,16 @@ static int build_id_cache__purge_all(void)
> static bool dso__missing_buildid_cache(struct dso *dso, int parm __maybe_unused)
> {
> char filename[PATH_MAX];
> - u8 build_id[BUILD_ID_SIZE];
> + struct build_id bid;
>
> if (dso__build_id_filename(dso, filename, sizeof(filename), false) &&
> - filename__read_build_id(filename, build_id,
> - sizeof(build_id)) != sizeof(build_id)) {
> + filename__read_build_id(filename, &bid) == -1) {
> if (errno == ENOENT)
> return false;
>
> pr_warning("Problems with %s file, consider removing it from the cache\n",
> filename);
> - } else if (memcmp(dso->bid.data, build_id, sizeof(dso->bid.data))) {
> + } else if (memcmp(dso->bid.data, bid.data, bid.size)) {
> pr_warning("Problems with %s file, consider removing it from the cache\n",
> filename);
> }
> @@ -300,14 +299,14 @@ static int build_id_cache__fprintf_missing(struct perf_session *session, FILE *f
>
> static int build_id_cache__update_file(const char *filename, struct nsinfo *nsi)
> {
> - u8 build_id[BUILD_ID_SIZE];
> char sbuild_id[SBUILD_ID_SIZE];
> + struct build_id bid;
> struct nscookie nsc;
>
> int err;
>
> nsinfo__mountns_enter(nsi, &nsc);
> - err = filename__read_build_id(filename, &build_id, sizeof(build_id));
> + err = filename__read_build_id(filename, &bid);
> nsinfo__mountns_exit(&nsc);
> if (err < 0) {
> pr_debug("Couldn't read a build-id in %s\n", filename);
> @@ -315,7 +314,7 @@ static int build_id_cache__update_file(const char *filename, struct nsinfo *nsi)
> }
> err = 0;
>
> - build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
> + build_id__sprintf(bid.data, sizeof(bid.data), sbuild_id);
> if (build_id_cache__cached(sbuild_id))
> err = build_id_cache__remove_s(sbuild_id);
>
> diff --git a/tools/perf/builtin-inject.c b/tools/perf/builtin-inject.c
> index 5cf32d8e3aa6..a7a5ac5ea9d5 100644
> --- a/tools/perf/builtin-inject.c
> +++ b/tools/perf/builtin-inject.c
> @@ -408,8 +408,7 @@ static int dso__read_build_id(struct dso *dso)
> if (dso->has_build_id)
> return 0;
>
> - if (filename__read_build_id(dso->long_name, dso->bid.data,
> - sizeof(dso->bid.data)) > 0) {
> + if (filename__read_build_id(dso->long_name, &dso->bid) > 0) {
> dso->has_build_id = true;
> return 0;
> }
> diff --git a/tools/perf/tests/pe-file-parsing.c b/tools/perf/tests/pe-file-parsing.c
> index 19eae3e8e229..58b90c42eb38 100644
> --- a/tools/perf/tests/pe-file-parsing.c
> +++ b/tools/perf/tests/pe-file-parsing.c
> @@ -24,7 +24,7 @@ static int run_dir(const char *d)
> {
> char filename[PATH_MAX];
> char debugfile[PATH_MAX];
> - char build_id[BUILD_ID_SIZE];
> + struct build_id bid;
> char debuglink[PATH_MAX];
> char expect_build_id[] = {
> 0x5a, 0x0f, 0xd8, 0x82, 0xb5, 0x30, 0x84, 0x22,
> @@ -36,10 +36,10 @@ static int run_dir(const char *d)
> int ret;
>
> scnprintf(filename, PATH_MAX, "%s/pe-file.exe", d);
> - ret = filename__read_build_id(filename, build_id, BUILD_ID_SIZE);
> + ret = filename__read_build_id(filename, &bid);
> TEST_ASSERT_VAL("Failed to read build_id",
> ret == sizeof(expect_build_id));
> - TEST_ASSERT_VAL("Wrong build_id", !memcmp(build_id, expect_build_id,
> + TEST_ASSERT_VAL("Wrong build_id", !memcmp(bid.data, expect_build_id,
> sizeof(expect_build_id)));
>
> ret = filename__read_debuglink(filename, debuglink, PATH_MAX);
> @@ -48,10 +48,10 @@ static int run_dir(const char *d)
> !strcmp(debuglink, expect_debuglink));
>
> scnprintf(debugfile, PATH_MAX, "%s/%s", d, debuglink);
> - ret = filename__read_build_id(debugfile, build_id, BUILD_ID_SIZE);
> + ret = filename__read_build_id(debugfile, &bid);
> TEST_ASSERT_VAL("Failed to read debug file build_id",
> ret == sizeof(expect_build_id));
> - TEST_ASSERT_VAL("Wrong build_id", !memcmp(build_id, expect_build_id,
> + TEST_ASSERT_VAL("Wrong build_id", !memcmp(bid.data, expect_build_id,
> sizeof(expect_build_id)));
>
> dso = dso__new(filename);
> diff --git a/tools/perf/tests/sdt.c b/tools/perf/tests/sdt.c
> index 60f0e9ee04fb..3ef37f739203 100644
> --- a/tools/perf/tests/sdt.c
> +++ b/tools/perf/tests/sdt.c
> @@ -28,16 +28,16 @@ static int target_function(void)
> static int build_id_cache__add_file(const char *filename)
> {
> char sbuild_id[SBUILD_ID_SIZE];
> - u8 build_id[BUILD_ID_SIZE];
> + struct build_id bid;
> int err;
>
> - err = filename__read_build_id(filename, &build_id, sizeof(build_id));
> + err = filename__read_build_id(filename, &bid);
> if (err < 0) {
> pr_debug("Failed to read build id of %s\n", filename);
> return err;
> }
>
> - build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
> + build_id__sprintf(bid.data, sizeof(bid.data), sbuild_id);
> err = build_id_cache__add_s(sbuild_id, filename, NULL, false, false);
> if (err < 0)
> pr_debug("Failed to add build id cache of %s\n", filename);
> diff --git a/tools/perf/util/build-id.c b/tools/perf/util/build-id.c
> index 7da13ddb0d50..62b258aaa128 100644
> --- a/tools/perf/util/build-id.c
> +++ b/tools/perf/util/build-id.c
> @@ -130,16 +130,14 @@ int sysfs__sprintf_build_id(const char *root_dir, char *sbuild_id)
>
> int filename__sprintf_build_id(const char *pathname, char *sbuild_id)
> {
> - u8 build_id[BUILD_ID_SIZE];
> + struct build_id bid;
> int ret;
>
> - ret = filename__read_build_id(pathname, build_id, sizeof(build_id));
> + ret = filename__read_build_id(pathname, &bid);
> if (ret < 0)
> return ret;
> - else if (ret != sizeof(build_id))
> - return -EINVAL;
>
> - return build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
> + return build_id__sprintf(bid.data, sizeof(bid.data), sbuild_id);
> }
>
> /* asnprintf consolidates asprintf and snprintf */
> diff --git a/tools/perf/util/dsos.c b/tools/perf/util/dsos.c
> index e3af46e818f1..87161e431830 100644
> --- a/tools/perf/util/dsos.c
> +++ b/tools/perf/util/dsos.c
> @@ -73,8 +73,7 @@ bool __dsos__read_build_ids(struct list_head *head, bool with_hits)
> continue;
> }
> nsinfo__mountns_enter(pos->nsinfo, &nsc);
> - if (filename__read_build_id(pos->long_name, pos->bid.data,
> - sizeof(pos->bid.data)) > 0) {
> + if (filename__read_build_id(pos->long_name, &pos->bid) > 0) {
> have_build_id = true;
> pos->has_build_id = true;
> }
> diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
> index 94a156df22d5..61d7c444e6f5 100644
> --- a/tools/perf/util/symbol-elf.c
> +++ b/tools/perf/util/symbol-elf.c
> @@ -534,8 +534,9 @@ static int elf_read_build_id(Elf *elf, void *bf, size_t size)
>
> #ifdef HAVE_LIBBFD_BUILDID_SUPPORT
>
> -int filename__read_build_id(const char *filename, void *bf, size_t size)
> +int filename__read_build_id(const char *filename, struct build_id *bid)
> {
> + size_t size = sizeof(bid->data);
> int err = -1;
> bfd *abfd;
>
> @@ -551,9 +552,9 @@ int filename__read_build_id(const char *filename, void *bf, size_t size)
> if (!abfd->build_id || abfd->build_id->size > size)
> goto out_close;
>
> - memcpy(bf, abfd->build_id->data, abfd->build_id->size);
> - memset(bf + abfd->build_id->size, 0, size - abfd->build_id->size);
> - err = abfd->build_id->size;
> + memcpy(bid->data, abfd->build_id->data, abfd->build_id->size);
> + memset(bid->data + abfd->build_id->size, 0, size - abfd->build_id->size);
> + err = bid->size = abfd->build_id->size;
>
> out_close:
> bfd_close(abfd);
> @@ -562,8 +563,9 @@ int filename__read_build_id(const char *filename, void *bf, size_t size)
>
> #else // HAVE_LIBBFD_BUILDID_SUPPORT
>
> -int filename__read_build_id(const char *filename, void *bf, size_t size)
> +int filename__read_build_id(const char *filename, struct build_id *bid)
> {
> + size_t size = sizeof(bid->data);
> int fd, err = -1;
> Elf *elf;
>
> @@ -580,7 +582,9 @@ int filename__read_build_id(const char *filename, void *bf, size_t size)
> goto out_close;
> }
>
> - err = elf_read_build_id(elf, bf, size);
> + err = elf_read_build_id(elf, bid->data, size);
> + if (err > 0)
> + bid->size = err;
>
> elf_end(elf);
> out_close:
> diff --git a/tools/perf/util/symbol-minimal.c b/tools/perf/util/symbol-minimal.c
> index d6e99af263ec..5173331ee6e4 100644
> --- a/tools/perf/util/symbol-minimal.c
> +++ b/tools/perf/util/symbol-minimal.c
> @@ -31,9 +31,10 @@ static bool check_need_swap(int file_endian)
>
> #define NT_GNU_BUILD_ID 3
>
> -static int read_build_id(void *note_data, size_t note_len, void *bf,
> - size_t size, bool need_swap)
> +static int read_build_id(void *note_data, size_t note_len, struct build_id *bid,
> + bool need_swap)
> {
> + size_t size = sizeof(bid->data);
> struct {
> u32 n_namesz;
> u32 n_descsz;
> @@ -63,8 +64,9 @@ static int read_build_id(void *note_data, size_t note_len, void *bf,
> nhdr->n_namesz == sizeof("GNU")) {
> if (memcmp(name, "GNU", sizeof("GNU")) == 0) {
> size_t sz = min(size, descsz);
> - memcpy(bf, ptr, sz);
> - memset(bf + sz, 0, size - sz);
> + memcpy(bid->data, ptr, sz);
> + memset(bid->data + sz, 0, size - sz);
> + bid->size = sz;
> return 0;
> }
> }
> @@ -84,7 +86,7 @@ int filename__read_debuglink(const char *filename __maybe_unused,
> /*
> * Just try PT_NOTE header otherwise fails
> */
> -int filename__read_build_id(const char *filename, void *bf, size_t size)
> +int filename__read_build_id(const char *filename, struct build_id *bid)
> {
> FILE *fp;
> int ret = -1;
> @@ -156,9 +158,9 @@ int filename__read_build_id(const char *filename, void *bf, size_t size)
> if (fread(buf, buf_size, 1, fp) != 1)
> goto out_free;
>
> - ret = read_build_id(buf, buf_size, bf, size, need_swap);
> + ret = read_build_id(buf, buf_size, bid, need_swap);
> if (ret == 0)
> - ret = size;
> + ret = bid->size;
> break;
> }
> } else {
> @@ -207,9 +209,9 @@ int filename__read_build_id(const char *filename, void *bf, size_t size)
> if (fread(buf, buf_size, 1, fp) != 1)
> goto out_free;
>
> - ret = read_build_id(buf, buf_size, bf, size, need_swap);
> + ret = read_build_id(buf, buf_size, bid, need_swap);
> if (ret == 0)
> - ret = size;
> + ret = bid->size;
> break;
> }
> }
> @@ -220,8 +222,9 @@ int filename__read_build_id(const char *filename, void *bf, size_t size)
> return ret;
> }
>
> -int sysfs__read_build_id(const char *filename, void *build_id, size_t size)
> +int sysfs__read_build_id(const char *filename, void *build_id, size_t size __maybe_unused)
> {
> + struct build_id bid;
> int fd;
> int ret = -1;
> struct stat stbuf;
> @@ -243,7 +246,9 @@ int sysfs__read_build_id(const char *filename, void *build_id, size_t size)
> if (read(fd, buf, buf_size) != (ssize_t) buf_size)
> goto out_free;
>
> - ret = read_build_id(buf, buf_size, build_id, size, false);
> + ret = read_build_id(buf, buf_size, &bid, false);
> + if (ret > 0)
> + memcpy(build_id, bid.data, bid.size);
> out_free:
> free(buf);
> out:
> @@ -339,16 +344,15 @@ int dso__load_sym(struct dso *dso, struct map *map __maybe_unused,
> struct symsrc *runtime_ss __maybe_unused,
> int kmodule __maybe_unused)
> {
> - unsigned char build_id[BUILD_ID_SIZE];
> + struct build_id bid;
> int ret;
>
> ret = fd__is_64_bit(ss->fd);
> if (ret >= 0)
> dso->is_64_bit = ret;
>
> - if (filename__read_build_id(ss->name, build_id, BUILD_ID_SIZE) > 0) {
> - dso__set_build_id(dso, build_id);
> - }
> + if (filename__read_build_id(ss->name, &bid) > 0)
> + dso__set_build_id(dso, bid.data);
> return 0;
> }
>
> diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
> index c772c8c70db5..4c43bb959fee 100644
> --- a/tools/perf/util/symbol.c
> +++ b/tools/perf/util/symbol.c
> @@ -1755,7 +1755,7 @@ int dso__load(struct dso *dso, struct map *map)
> struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
> bool kmod;
> bool perfmap;
> - unsigned char build_id[BUILD_ID_SIZE];
> + struct build_id bid;
> struct nscookie nsc;
> char newmapname[PATH_MAX];
> const char *map_path = dso->long_name;
> @@ -1817,8 +1817,8 @@ int dso__load(struct dso *dso, struct map *map)
> if (!dso->has_build_id &&
> is_regular_file(dso->long_name)) {
> __symbol__join_symfs(name, PATH_MAX, dso->long_name);
> - if (filename__read_build_id(name, build_id, BUILD_ID_SIZE) > 0)
> - dso__set_build_id(dso, build_id);
> + if (filename__read_build_id(name, &bid) > 0)
> + dso__set_build_id(dso, bid.data);
> }
>
> /*
> diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
> index 11fe71f46d14..98908fa3f796 100644
> --- a/tools/perf/util/symbol.h
> +++ b/tools/perf/util/symbol.h
> @@ -23,6 +23,7 @@ struct dso;
> struct map;
> struct maps;
> struct option;
> +struct build_id;
>
> /*
> * libelf 0.8.x and earlier do not support ELF_C_READ_MMAP;
> @@ -142,7 +143,7 @@ struct symbol *dso__next_symbol(struct symbol *sym);
>
> enum dso_type dso__type_fd(int fd);
>
> -int filename__read_build_id(const char *filename, void *bf, size_t size);
> +int filename__read_build_id(const char *filename, struct build_id *id);
> int sysfs__read_build_id(const char *filename, void *bf, size_t size);
> int modules__parse(const char *filename, void *arg,
> int (*process_module)(void *arg, const char *name,
> --
> 2.26.2
>