diff options
Diffstat (limited to 'tools/perf/util/debuginfo.c')
| -rw-r--r-- | tools/perf/util/debuginfo.c | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/tools/perf/util/debuginfo.c b/tools/perf/util/debuginfo.c new file mode 100644 index 0000000000..19acf4775d --- /dev/null +++ b/tools/perf/util/debuginfo.c @@ -0,0 +1,205 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * DWARF debug information handling code. Copied from probe-finder.c. + * + * Written by Masami Hiramatsu <mhiramat@redhat.com> + */ + +#include <errno.h> +#include <fcntl.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <linux/zalloc.h> + +#include "build-id.h" +#include "dso.h" +#include "debug.h" +#include "debuginfo.h" +#include "symbol.h" + +#ifdef HAVE_DEBUGINFOD_SUPPORT +#include <elfutils/debuginfod.h> +#endif + +/* Dwarf FL wrappers */ +static char *debuginfo_path; /* Currently dummy */ + +static const Dwfl_Callbacks offline_callbacks = { + .find_debuginfo = dwfl_standard_find_debuginfo, + .debuginfo_path = &debuginfo_path, + + .section_address = dwfl_offline_section_address, + + /* We use this table for core files too. */ + .find_elf = dwfl_build_id_find_elf, +}; + +/* Get a Dwarf from offline image */ +static int debuginfo__init_offline_dwarf(struct debuginfo *dbg, + const char *path) +{ + GElf_Addr dummy; + int fd; + + fd = open(path, O_RDONLY); + if (fd < 0) + return fd; + + dbg->dwfl = dwfl_begin(&offline_callbacks); + if (!dbg->dwfl) + goto error; + + dwfl_report_begin(dbg->dwfl); + dbg->mod = dwfl_report_offline(dbg->dwfl, "", "", fd); + if (!dbg->mod) + goto error; + + dbg->dbg = dwfl_module_getdwarf(dbg->mod, &dbg->bias); + if (!dbg->dbg) + goto error; + + dwfl_module_build_id(dbg->mod, &dbg->build_id, &dummy); + + dwfl_report_end(dbg->dwfl, NULL, NULL); + + return 0; +error: + if (dbg->dwfl) + dwfl_end(dbg->dwfl); + else + close(fd); + memset(dbg, 0, sizeof(*dbg)); + + return -ENOENT; +} + +static struct debuginfo *__debuginfo__new(const char *path) +{ + struct debuginfo *dbg = zalloc(sizeof(*dbg)); + if (!dbg) + return NULL; + + if (debuginfo__init_offline_dwarf(dbg, path) < 0) + zfree(&dbg); + if (dbg) + pr_debug("Open Debuginfo file: %s\n", path); + return dbg; +} + +enum dso_binary_type distro_dwarf_types[] = { + DSO_BINARY_TYPE__FEDORA_DEBUGINFO, + DSO_BINARY_TYPE__UBUNTU_DEBUGINFO, + DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO, + DSO_BINARY_TYPE__BUILDID_DEBUGINFO, + DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO, + DSO_BINARY_TYPE__NOT_FOUND, +}; + +struct debuginfo *debuginfo__new(const char *path) +{ + enum dso_binary_type *type; + char buf[PATH_MAX], nil = '\0'; + struct dso *dso; + struct debuginfo *dinfo = NULL; + struct build_id bid; + + /* Try to open distro debuginfo files */ + dso = dso__new(path); + if (!dso) + goto out; + + /* Set the build id for DSO_BINARY_TYPE__BUILDID_DEBUGINFO */ + if (is_regular_file(path) && filename__read_build_id(path, &bid) > 0) + dso__set_build_id(dso, &bid); + + for (type = distro_dwarf_types; + !dinfo && *type != DSO_BINARY_TYPE__NOT_FOUND; + type++) { + if (dso__read_binary_type_filename(dso, *type, &nil, + buf, PATH_MAX) < 0) + continue; + dinfo = __debuginfo__new(buf); + } + dso__put(dso); + +out: + /* if failed to open all distro debuginfo, open given binary */ + return dinfo ? : __debuginfo__new(path); +} + +void debuginfo__delete(struct debuginfo *dbg) +{ + if (dbg) { + if (dbg->dwfl) + dwfl_end(dbg->dwfl); + free(dbg); + } +} + +/* For the kernel module, we need a special code to get a DIE */ +int debuginfo__get_text_offset(struct debuginfo *dbg, Dwarf_Addr *offs, + bool adjust_offset) +{ + int n, i; + Elf32_Word shndx; + Elf_Scn *scn; + Elf *elf; + GElf_Shdr mem, *shdr; + const char *p; + + elf = dwfl_module_getelf(dbg->mod, &dbg->bias); + if (!elf) + return -EINVAL; + + /* Get the number of relocations */ + n = dwfl_module_relocations(dbg->mod); + if (n < 0) + return -ENOENT; + /* Search the relocation related .text section */ + for (i = 0; i < n; i++) { + p = dwfl_module_relocation_info(dbg->mod, i, &shndx); + if (strcmp(p, ".text") == 0) { + /* OK, get the section header */ + scn = elf_getscn(elf, shndx); + if (!scn) + return -ENOENT; + shdr = gelf_getshdr(scn, &mem); + if (!shdr) + return -ENOENT; + *offs = shdr->sh_addr; + if (adjust_offset) + *offs -= shdr->sh_offset; + } + } + return 0; +} + +#ifdef HAVE_DEBUGINFOD_SUPPORT +int get_source_from_debuginfod(const char *raw_path, + const char *sbuild_id, char **new_path) +{ + debuginfod_client *c = debuginfod_begin(); + const char *p = raw_path; + int fd; + + if (!c) + return -ENOMEM; + + fd = debuginfod_find_source(c, (const unsigned char *)sbuild_id, + 0, p, new_path); + pr_debug("Search %s from debuginfod -> %d\n", p, fd); + if (fd >= 0) + close(fd); + debuginfod_end(c); + if (fd < 0) { + pr_debug("Failed to find %s in debuginfod (%s)\n", + raw_path, sbuild_id); + return -ENOENT; + } + pr_debug("Got a source %s\n", *new_path); + + return 0; +} +#endif /* HAVE_DEBUGINFOD_SUPPORT */ |