From 261360b6e90a782f0a63d8f61a67683c376c88cf Mon Sep 17 00:00:00 2001 From: Cody P Schafer Date: Fri, 10 Aug 2012 15:23:01 -0700 Subject: [PATCH] perf symbols: Convert dso__load_syms to take 2 symsrc's To properly handle platforms with an opd section, both a runtime image (which contains the opd section but possibly lacks symbols) and a symbol image (which probably lacks an opd section but has symbols). The next patch ("perf symbol: use both runtime and debug images") adjusts the callsite in dso__load() to take advantage of being able to pass both runtime & debug images. Assumptions made here: - The opd section, if it exists in the runtime image, has headers in both the runtime image and the debug/syms image. - The index of the opd section (again, only if it exists in the runtime image) is the same in both the runtime and debug/symbols image. Both of these are true on RHEL, but it is unclear how accurate they are in general (on platforms with function descriptors in opd sections). Signed-off-by: Cody P Schafer Cc: David Hansen Cc: Ingo Molnar Cc: Matt Hellsley Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Sukadev Bhattiprolu Link: http://lkml.kernel.org/r/1344637382-22789-16-git-send-email-cody@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/symbol-elf.c | 47 ++++++++++++++++---------------- tools/perf/util/symbol-minimal.c | 1 + tools/perf/util/symbol.c | 4 +-- tools/perf/util/symbol.h | 5 ++-- 4 files changed, 30 insertions(+), 27 deletions(-) diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c index 492ebecfbfb6..36e4a458e7a1 100644 --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -619,7 +619,8 @@ int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name, return err; } -int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *ss, +int dso__load_sym(struct dso *dso, struct map *map, + struct symsrc *syms_ss, struct symsrc *runtime_ss, symbol_filter_t filter, int kmodule) { struct kmap *kmap = dso->kernel ? map__kmap(map) : NULL; @@ -630,31 +631,27 @@ int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *ss, int err = -1; uint32_t idx; GElf_Ehdr ehdr; - GElf_Shdr shdr, opdshdr; + GElf_Shdr shdr; Elf_Data *syms, *opddata = NULL; GElf_Sym sym; - Elf_Scn *sec, *sec_strndx, *opdsec; + Elf_Scn *sec, *sec_strndx; Elf *elf; int nr = 0; - size_t opdidx = 0; - dso->symtab_type = ss->type; + dso->symtab_type = syms_ss->type; - if (!ss->symtab) { - ss->symtab = ss->dynsym; - ss->symshdr = ss->dynshdr; + if (!syms_ss->symtab) { + syms_ss->symtab = syms_ss->dynsym; + syms_ss->symshdr = syms_ss->dynshdr; } - elf = ss->elf; - ehdr = ss->ehdr; - sec = ss->symtab; - shdr = ss->symshdr; + elf = syms_ss->elf; + ehdr = syms_ss->ehdr; + sec = syms_ss->symtab; + shdr = syms_ss->symshdr; - opdsec = ss->opdsec; - opdshdr = ss->opdshdr; - opdidx = ss->opdidx; - if (opdsec) - opddata = elf_rawdata(opdsec, NULL); + if (runtime_ss->opdsec) + opddata = elf_rawdata(runtime_ss->opdsec, NULL); syms = elf_getdata(sec, NULL); if (syms == NULL) @@ -679,13 +676,14 @@ int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *ss, nr_syms = shdr.sh_size / shdr.sh_entsize; memset(&sym, 0, sizeof(sym)); - dso->adjust_symbols = ss->adjust_symbols; + dso->adjust_symbols = runtime_ss->adjust_symbols; elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) { struct symbol *f; const char *elf_name = elf_sym__name(&sym, symstrs); char *demangled = NULL; int is_label = elf_sym__is_label(&sym); const char *section_name; + bool used_opd = false; if (kmap && kmap->ref_reloc_sym && kmap->ref_reloc_sym->name && strcmp(elf_name, kmap->ref_reloc_sym->name) == 0) @@ -704,14 +702,16 @@ int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *ss, continue; } - if (opdsec && sym.st_shndx == opdidx) { - u32 offset = sym.st_value - opdshdr.sh_addr; + if (runtime_ss->opdsec && sym.st_shndx == runtime_ss->opdidx) { + u32 offset = sym.st_value - syms_ss->opdshdr.sh_addr; u64 *opd = opddata->d_buf + offset; sym.st_value = DSO__SWAP(dso, u64, *opd); - sym.st_shndx = elf_addr_to_index(elf, sym.st_value); + sym.st_shndx = elf_addr_to_index(runtime_ss->elf, + sym.st_value); + used_opd = true; } - sec = elf_getscn(elf, sym.st_shndx); + sec = elf_getscn(runtime_ss->elf, sym.st_shndx); if (!sec) goto out_elf_end; @@ -777,7 +777,8 @@ int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *ss, goto new_symbol; } - if (curr_dso->adjust_symbols && sym.st_value) { + if ((used_opd && runtime_ss->adjust_symbols) + || (!used_opd && syms_ss->adjust_symbols)) { pr_debug4("%s: adjusting symbol: st_value: %#" PRIx64 " " "sh_addr: %#" PRIx64 " sh_offset: %#" PRIx64 "\n", __func__, (u64)sym.st_value, (u64)shdr.sh_addr, diff --git a/tools/perf/util/symbol-minimal.c b/tools/perf/util/symbol-minimal.c index 11c2c606ce77..7747ea6d7e97 100644 --- a/tools/perf/util/symbol-minimal.c +++ b/tools/perf/util/symbol-minimal.c @@ -280,6 +280,7 @@ int dso__synthesize_plt_symbols(struct dso *dso __used, } int dso__load_sym(struct dso *dso, struct map *map __used, struct symsrc *ss, + struct symsrc *runtime_ss __used, symbol_filter_t filter __used, int kmodule __used) { unsigned char *build_id[BUILD_ID_SIZE]; diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index 8e7d74ff6ba5..739e5a32366a 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -1094,7 +1094,7 @@ int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter) continue; } - ret = dso__load_sym(dso, map, &ss, filter, 0); + ret = dso__load_sym(dso, map, &ss, &ss, filter, 0); /* * Some people seem to have debuginfo files _WITHOUT_ debug @@ -1380,7 +1380,7 @@ int dso__load_vmlinux(struct dso *dso, struct map *map, if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type)) return -1; - err = dso__load_sym(dso, map, &ss, filter, 0); + err = dso__load_sym(dso, map, &ss, &ss, filter, 0); symsrc__destroy(&ss); if (err > 0) { diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h index fa9f6b1cdc46..1f3eed21f35d 100644 --- a/tools/perf/util/symbol.h +++ b/tools/perf/util/symbol.h @@ -369,8 +369,9 @@ ssize_t dso__data_read_addr(struct dso *dso, struct map *map, struct machine *machine, u64 addr, u8 *data, ssize_t size); int dso__test_data(void); -int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *ss, - symbol_filter_t filter, int kmodule); +int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *syms_ss, + struct symsrc *runtime_ss, symbol_filter_t filter, + int kmodule); int dso__synthesize_plt_symbols(struct dso *dso, struct symsrc *ss, struct map *map, symbol_filter_t filter); -- GitLab