diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2025-10-08 19:24:24 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2025-10-08 19:24:24 -0700 |
commit | ec714e371f22f716a04e6ecb2a24988c92b26911 (patch) | |
tree | 02ef2ebccd6889590b2b42697b6f83ca22ff8127 /tools/perf/util/libbfd.c | |
parent | 37bfdbc11b245119210ac9924a192aec8bd07d16 (diff) | |
parent | f3b601f900902ab80902c44f820a8985384ac021 (diff) |
Merge tag 'perf-tools-for-v6.18-1-2025-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-toolsHEADmaster
Pull perf tools updates from Arnaldo Carvalho de Melo:
- Extended 'perf annotate' with DWARF type information
(--code-with-type) integration in the TUI, including a 'T'
hotkey to toggle it
- Enhanced 'perf bench mem' with new mmap() workloads and control
over page/chunk sizes
- Fix 'perf stat' error handling to correctly display unsupported
events
- Improved support for Clang cross-compilation
- Refactored LLVM and Capstone disasm for modularity
- Introduced the :X modifier to exclude an event from automatic
regrouping
- Adjusted KVM sampling defaults to use the "cycles" event to prevent
failures
- Added comprehensive support for decoding PowerPC Dispatch Trace Log
(DTL)
- Updated Arm SPE tracing logic for better analysis of memory and snoop
details
- Synchronized Intel PMU events and metrics with TMA 5.1 across
multiple processor generations
- Converted dependencies like libperl and libtracefs to be opt-in
- Handle more Rust symbols in kallsyms ('N', debugging)
- Improve the python binding to allow for python based tools to use
more of the libraries, add a 'ilist' utility to test those new
bindings
- Various 'perf test' fixes
- Kan Liang no longer a perf tools reviewer
* tag 'perf-tools-for-v6.18-1-2025-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (192 commits)
perf tools: Fix arm64 libjvmti build by generating unistd_64.h
perf tests: Don't retest sections in "Object code reading"
perf docs: Document building with Clang
perf build: Support build with clang
perf test coresight: Dismiss clang warning for unroll loop thread
perf test coresight: Dismiss clang warning for thread loop
perf test coresight: Dismiss clang warning for memcpy thread
perf build: Disable thread safety analysis for perl header
perf build: Correct CROSS_ARCH for clang
perf python: split Clang options when invoking Popen
tools build: Align warning options with perf
perf disasm: Remove unused evsel from 'struct annotate_args'
perf srcline: Fallback between addr2line implementations
perf disasm: Make ins__scnprintf() and ins__is_nop() static
perf dso: Clean up read_symbol() error handling
perf dso: Support BPF programs in dso__read_symbol()
perf dso: Move read_symbol() from llvm/capstone to dso
perf llvm: Reduce LLVM initialization
perf check: Add libLLVM feature
perf parse-events: Fix parsing of >30kb event strings
...
Diffstat (limited to 'tools/perf/util/libbfd.c')
-rw-r--r-- | tools/perf/util/libbfd.c | 600 |
1 files changed, 600 insertions, 0 deletions
diff --git a/tools/perf/util/libbfd.c b/tools/perf/util/libbfd.c new file mode 100644 index 000000000000..01147fbf73b3 --- /dev/null +++ b/tools/perf/util/libbfd.c @@ -0,0 +1,600 @@ +// SPDX-License-Identifier: GPL-2.0 +#include "libbfd.h" +#include "annotate.h" +#include "bpf-event.h" +#include "bpf-utils.h" +#include "debug.h" +#include "dso.h" +#include "env.h" +#include "map.h" +#include "srcline.h" +#include "symbol.h" +#include "symbol_conf.h" +#include "util.h" +#include <tools/dis-asm-compat.h> +#ifdef HAVE_LIBBPF_SUPPORT +#include <bpf/bpf.h> +#include <bpf/btf.h> +#endif +#include <fcntl.h> +#include <stdio.h> +#include <stdlib.h> +#define PACKAGE "perf" +#include <bfd.h> + +/* + * Implement addr2line using libbfd. + */ +struct a2l_data { + const char *input; + u64 addr; + + bool found; + const char *filename; + const char *funcname; + unsigned int line; + + bfd *abfd; + asymbol **syms; +}; + +static int bfd_error(const char *string) +{ + const char *errmsg; + + errmsg = bfd_errmsg(bfd_get_error()); + fflush(stdout); + + if (string) + pr_debug("%s: %s\n", string, errmsg); + else + pr_debug("%s\n", errmsg); + + return -1; +} + +static int slurp_symtab(bfd *abfd, struct a2l_data *a2l) +{ + long storage; + long symcount; + asymbol **syms; + bfd_boolean dynamic = FALSE; + + if ((bfd_get_file_flags(abfd) & HAS_SYMS) == 0) + return bfd_error(bfd_get_filename(abfd)); + + storage = bfd_get_symtab_upper_bound(abfd); + if (storage == 0L) { + storage = bfd_get_dynamic_symtab_upper_bound(abfd); + dynamic = TRUE; + } + if (storage < 0L) + return bfd_error(bfd_get_filename(abfd)); + + syms = malloc(storage); + if (dynamic) + symcount = bfd_canonicalize_dynamic_symtab(abfd, syms); + else + symcount = bfd_canonicalize_symtab(abfd, syms); + + if (symcount < 0) { + free(syms); + return bfd_error(bfd_get_filename(abfd)); + } + + a2l->syms = syms; + return 0; +} + +static void find_address_in_section(bfd *abfd, asection *section, void *data) +{ + bfd_vma pc, vma; + bfd_size_type size; + struct a2l_data *a2l = data; + flagword flags; + + if (a2l->found) + return; + +#ifdef bfd_get_section_flags + flags = bfd_get_section_flags(abfd, section); +#else + flags = bfd_section_flags(section); +#endif + if ((flags & SEC_ALLOC) == 0) + return; + + pc = a2l->addr; +#ifdef bfd_get_section_vma + vma = bfd_get_section_vma(abfd, section); +#else + vma = bfd_section_vma(section); +#endif +#ifdef bfd_get_section_size + size = bfd_get_section_size(section); +#else + size = bfd_section_size(section); +#endif + + if (pc < vma || pc >= vma + size) + return; + + a2l->found = bfd_find_nearest_line(abfd, section, a2l->syms, pc - vma, + &a2l->filename, &a2l->funcname, + &a2l->line); + + if (a2l->filename && !strlen(a2l->filename)) + a2l->filename = NULL; +} + +static struct a2l_data *addr2line_init(const char *path) +{ + bfd *abfd; + struct a2l_data *a2l = NULL; + + abfd = bfd_openr(path, NULL); + if (abfd == NULL) + return NULL; + + if (!bfd_check_format(abfd, bfd_object)) + goto out; + + a2l = zalloc(sizeof(*a2l)); + if (a2l == NULL) + goto out; + + a2l->abfd = abfd; + a2l->input = strdup(path); + if (a2l->input == NULL) + goto out; + + if (slurp_symtab(abfd, a2l)) + goto out; + + return a2l; + +out: + if (a2l) { + zfree((char **)&a2l->input); + free(a2l); + } + bfd_close(abfd); + return NULL; +} + +static void addr2line_cleanup(struct a2l_data *a2l) +{ + if (a2l->abfd) + bfd_close(a2l->abfd); + zfree((char **)&a2l->input); + zfree(&a2l->syms); + free(a2l); +} + +static int inline_list__append_dso_a2l(struct dso *dso, + struct inline_node *node, + struct symbol *sym) +{ + struct a2l_data *a2l = dso__a2l(dso); + struct symbol *inline_sym = new_inline_sym(dso, sym, a2l->funcname); + char *srcline = NULL; + + if (a2l->filename) + srcline = srcline_from_fileline(a2l->filename, a2l->line); + + return inline_list__append(inline_sym, srcline, node); +} + +int libbfd__addr2line(const char *dso_name, u64 addr, + char **file, unsigned int *line, struct dso *dso, + bool unwind_inlines, struct inline_node *node, + struct symbol *sym) +{ + int ret = 0; + struct a2l_data *a2l = dso__a2l(dso); + + if (!a2l) { + a2l = addr2line_init(dso_name); + dso__set_a2l(dso, a2l); + } + + if (a2l == NULL) { + if (!symbol_conf.disable_add2line_warn) + pr_warning("addr2line_init failed for %s\n", dso_name); + return 0; + } + + a2l->addr = addr; + a2l->found = false; + + bfd_map_over_sections(a2l->abfd, find_address_in_section, a2l); + + if (!a2l->found) + return 0; + + if (unwind_inlines) { + int cnt = 0; + + if (node && inline_list__append_dso_a2l(dso, node, sym)) + return 0; + + while (bfd_find_inliner_info(a2l->abfd, &a2l->filename, + &a2l->funcname, &a2l->line) && + cnt++ < MAX_INLINE_NEST) { + + if (a2l->filename && !strlen(a2l->filename)) + a2l->filename = NULL; + + if (node != NULL) { + if (inline_list__append_dso_a2l(dso, node, sym)) + return 0; + // found at least one inline frame + ret = 1; + } + } + } + + if (file) { + *file = a2l->filename ? strdup(a2l->filename) : NULL; + ret = *file ? 1 : 0; + } + + if (line) + *line = a2l->line; + + return ret; +} + +void dso__free_a2l_libbfd(struct dso *dso) +{ + struct a2l_data *a2l = dso__a2l(dso); + + if (!a2l) + return; + + addr2line_cleanup(a2l); + + dso__set_a2l(dso, NULL); +} + +static int bfd_symbols__cmpvalue(const void *a, const void *b) +{ + const asymbol *as = *(const asymbol **)a, *bs = *(const asymbol **)b; + + if (bfd_asymbol_value(as) != bfd_asymbol_value(bs)) + return bfd_asymbol_value(as) - bfd_asymbol_value(bs); + + return bfd_asymbol_name(as)[0] - bfd_asymbol_name(bs)[0]; +} + +static int bfd2elf_binding(asymbol *symbol) +{ + if (symbol->flags & BSF_WEAK) + return STB_WEAK; + if (symbol->flags & BSF_GLOBAL) + return STB_GLOBAL; + if (symbol->flags & BSF_LOCAL) + return STB_LOCAL; + return -1; +} + +int dso__load_bfd_symbols(struct dso *dso, const char *debugfile) +{ + int err = -1; + long symbols_size, symbols_count, i; + asection *section; + asymbol **symbols, *sym; + struct symbol *symbol; + bfd *abfd; + u64 start, len; + + abfd = bfd_openr(debugfile, NULL); + if (!abfd) + return -1; + + if (!bfd_check_format(abfd, bfd_object)) { + pr_debug2("%s: cannot read %s bfd file.\n", __func__, + dso__long_name(dso)); + goto out_close; + } + + if (bfd_get_flavour(abfd) == bfd_target_elf_flavour) + goto out_close; + + symbols_size = bfd_get_symtab_upper_bound(abfd); + if (symbols_size == 0) { + bfd_close(abfd); + return 0; + } + + if (symbols_size < 0) + goto out_close; + + symbols = malloc(symbols_size); + if (!symbols) + goto out_close; + + symbols_count = bfd_canonicalize_symtab(abfd, symbols); + if (symbols_count < 0) + goto out_free; + + section = bfd_get_section_by_name(abfd, ".text"); + if (section) { + for (i = 0; i < symbols_count; ++i) { + if (!strcmp(bfd_asymbol_name(symbols[i]), "__ImageBase") || + !strcmp(bfd_asymbol_name(symbols[i]), "__image_base__")) + break; + } + if (i < symbols_count) { + /* PE symbols can only have 4 bytes, so use .text high bits */ + u64 text_offset = (section->vma - (u32)section->vma) + + (u32)bfd_asymbol_value(symbols[i]); + dso__set_text_offset(dso, text_offset); + dso__set_text_end(dso, (section->vma - text_offset) + section->size); + } else { + dso__set_text_offset(dso, section->vma - section->filepos); + dso__set_text_end(dso, section->filepos + section->size); + } + } + + qsort(symbols, symbols_count, sizeof(asymbol *), bfd_symbols__cmpvalue); + +#ifdef bfd_get_section +#define bfd_asymbol_section bfd_get_section +#endif + for (i = 0; i < symbols_count; ++i) { + sym = symbols[i]; + section = bfd_asymbol_section(sym); + if (bfd2elf_binding(sym) < 0) + continue; + + while (i + 1 < symbols_count && + bfd_asymbol_section(symbols[i + 1]) == section && + bfd2elf_binding(symbols[i + 1]) < 0) + i++; + + if (i + 1 < symbols_count && + bfd_asymbol_section(symbols[i + 1]) == section) + len = symbols[i + 1]->value - sym->value; + else + len = section->size - sym->value; + + start = bfd_asymbol_value(sym) - dso__text_offset(dso); + symbol = symbol__new(start, len, bfd2elf_binding(sym), STT_FUNC, + bfd_asymbol_name(sym)); + if (!symbol) + goto out_free; + + symbols__insert(dso__symbols(dso), symbol); + } +#ifdef bfd_get_section +#undef bfd_asymbol_section +#endif + + symbols__fixup_end(dso__symbols(dso), false); + symbols__fixup_duplicate(dso__symbols(dso)); + dso__set_adjust_symbols(dso, true); + + err = 0; +out_free: + free(symbols); +out_close: + bfd_close(abfd); + return err; +} + +int libbfd__read_build_id(const char *filename, struct build_id *bid, bool block) +{ + size_t size = sizeof(bid->data); + int err = -1, fd; + bfd *abfd; + + fd = open(filename, block ? O_RDONLY : (O_RDONLY | O_NONBLOCK)); + if (fd < 0) + return -1; + + abfd = bfd_fdopenr(filename, /*target=*/NULL, fd); + if (!abfd) + return -1; + + if (!bfd_check_format(abfd, bfd_object)) { + pr_debug2("%s: cannot read %s bfd file.\n", __func__, filename); + goto out_close; + } + + if (!abfd->build_id || abfd->build_id->size > size) + goto out_close; + + 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); + return err; +} + +int libbfd_filename__read_debuglink(const char *filename, char *debuglink, + size_t size) +{ + int err = -1; + asection *section; + bfd *abfd; + + abfd = bfd_openr(filename, NULL); + if (!abfd) + return -1; + + if (!bfd_check_format(abfd, bfd_object)) { + pr_debug2("%s: cannot read %s bfd file.\n", __func__, filename); + goto out_close; + } + + section = bfd_get_section_by_name(abfd, ".gnu_debuglink"); + if (!section) + goto out_close; + + if (section->size > size) + goto out_close; + + if (!bfd_get_section_contents(abfd, section, debuglink, 0, + section->size)) + goto out_close; + + err = 0; + +out_close: + bfd_close(abfd); + return err; +} + +int symbol__disassemble_bpf_libbfd(struct symbol *sym __maybe_unused, + struct annotate_args *args __maybe_unused) +{ +#ifdef HAVE_LIBBPF_SUPPORT + struct annotation *notes = symbol__annotation(sym); + struct bpf_prog_linfo *prog_linfo = NULL; + struct bpf_prog_info_node *info_node; + int len = sym->end - sym->start; + disassembler_ftype disassemble; + struct map *map = args->ms.map; + struct perf_bpil *info_linear; + struct disassemble_info info; + struct dso *dso = map__dso(map); + int pc = 0, count, sub_id; + struct btf *btf = NULL; + char tpath[PATH_MAX]; + size_t buf_size; + int nr_skip = 0; + char *buf; + bfd *bfdf; + int ret; + FILE *s; + + if (dso__binary_type(dso) != DSO_BINARY_TYPE__BPF_PROG_INFO) + return SYMBOL_ANNOTATE_ERRNO__BPF_INVALID_FILE; + + pr_debug("%s: handling sym %s addr %" PRIx64 " len %" PRIx64 "\n", __func__, + sym->name, sym->start, sym->end - sym->start); + + memset(tpath, 0, sizeof(tpath)); + perf_exe(tpath, sizeof(tpath)); + + bfdf = bfd_openr(tpath, NULL); + if (bfdf == NULL) + abort(); + + if (!bfd_check_format(bfdf, bfd_object)) + abort(); + + s = open_memstream(&buf, &buf_size); + if (!s) { + ret = errno; + goto out; + } + init_disassemble_info_compat(&info, s, + (fprintf_ftype) fprintf, + fprintf_styled); + info.arch = bfd_get_arch(bfdf); + info.mach = bfd_get_mach(bfdf); + + info_node = perf_env__find_bpf_prog_info(dso__bpf_prog(dso)->env, + dso__bpf_prog(dso)->id); + if (!info_node) { + ret = SYMBOL_ANNOTATE_ERRNO__BPF_MISSING_BTF; + goto out; + } + info_linear = info_node->info_linear; + sub_id = dso__bpf_prog(dso)->sub_id; + + info.buffer = (void *)(uintptr_t)(info_linear->info.jited_prog_insns); + info.buffer_length = info_linear->info.jited_prog_len; + + if (info_linear->info.nr_line_info) + prog_linfo = bpf_prog_linfo__new(&info_linear->info); + + if (info_linear->info.btf_id) { + struct btf_node *node; + + node = perf_env__find_btf(dso__bpf_prog(dso)->env, + info_linear->info.btf_id); + if (node) + btf = btf__new((__u8 *)(node->data), + node->data_size); + } + + disassemble_init_for_target(&info); + +#ifdef DISASM_FOUR_ARGS_SIGNATURE + disassemble = disassembler(info.arch, + bfd_big_endian(bfdf), + info.mach, + bfdf); +#else + disassemble = disassembler(bfdf); +#endif + if (disassemble == NULL) + abort(); + + fflush(s); + do { + const struct bpf_line_info *linfo = NULL; + struct disasm_line *dl; + size_t prev_buf_size; + const char *srcline; + u64 addr; + + addr = pc + ((u64 *)(uintptr_t)(info_linear->info.jited_ksyms))[sub_id]; + count = disassemble(pc, &info); + + if (prog_linfo) + linfo = bpf_prog_linfo__lfind_addr_func(prog_linfo, + addr, sub_id, + nr_skip); + + if (linfo && btf) { + srcline = btf__name_by_offset(btf, linfo->line_off); + nr_skip++; + } else + srcline = NULL; + + fprintf(s, "\n"); + prev_buf_size = buf_size; + fflush(s); + + if (!annotate_opts.hide_src_code && srcline) { + args->offset = -1; + args->line = strdup(srcline); + args->line_nr = 0; + args->fileloc = NULL; + args->ms.sym = sym; + dl = disasm_line__new(args); + if (dl) { + annotation_line__add(&dl->al, + ¬es->src->source); + } + } + + args->offset = pc; + args->line = buf + prev_buf_size; + args->line_nr = 0; + args->fileloc = NULL; + args->ms.sym = sym; + dl = disasm_line__new(args); + if (dl) + annotation_line__add(&dl->al, ¬es->src->source); + + pc += count; + } while (count > 0 && pc < len); + + ret = 0; +out: + free(prog_linfo); + btf__free(btf); + fclose(s); + bfd_close(bfdf); + return ret; +#else + return SYMBOL_ANNOTATE_ERRNO__NO_LIBOPCODES_FOR_BPF; +#endif +} |