Commit-ID: 3aafe5ae08f2aed378e06d78b207883879d25cbe Gitweb: http://git.kernel.org/tip/3aafe5ae08f2aed378e06d78b207883879d25cbe Author: Cody P Schafer <c...@linux.vnet.ibm.com> AuthorDate: Fri, 10 Aug 2012 15:23:02 -0700 Committer: Arnaldo Carvalho de Melo <a...@redhat.com> CommitDate: Mon, 13 Aug 2012 14:46:55 -0300
perf symbols: Use both runtime and debug images We keep both a 'runtime' elf image as well as a 'debug' elf image around and generate symbols by looking at both of these. This eliminates the need for the want_symtab/goto restart mechanism combined with iterating over and reopening the elf images a second time. Also give dso__synthsize_plt_symbols() the runtime image (which has dynsyms) instead of the symbol image (which may only have a symtab and no dynsyms). Previously if a debug image was found all runtime images were ignored. This fixes 2 issues: - Symbol resolution to failure on PowerPC systems with debug symbols installed, as the debug images lack a '.opd' section which contains function descriptors. - On all archs, plt synthesis failed when a debug image was loaded and that debug image lacks a dynsym section while a runtime image has a dynsym section. Assumptions: - If a .opd section exists, it is contained in the highest priority image with a dynsym section. - This generally implies that the debug image lacks a dynsym section (ie: it is marked as NO_BITS). Signed-off-by: Cody P Schafer <c...@linux.vnet.ibm.com> Cc: David Hansen <d...@linux.vnet.ibm.com> Cc: Ingo Molnar <mi...@redhat.com> Cc: Matt Hellsley <matth...@us.ibm.com> Cc: Namhyung Kim <namhy...@kernel.org> Cc: Paul Mackerras <pau...@samba.org> Cc: Peter Zijlstra <a.p.zijls...@chello.nl> Cc: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/1344637382-22789-17-git-send-email-c...@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com> --- tools/perf/util/symbol-elf.c | 5 ++ tools/perf/util/symbol-minimal.c | 6 +++ tools/perf/util/symbol.c | 77 +++++++++++++++++++++---------------- tools/perf/util/symbol.h | 1 + 4 files changed, 56 insertions(+), 33 deletions(-) diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c index 36e4a45..5b37e13 100644 --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -525,6 +525,11 @@ static int dso__swap_init(struct dso *dso, unsigned char eidata) return 0; } +bool symsrc__possibly_runtime(struct symsrc *ss) +{ + return ss->dynsym || ss->opdsec; +} + bool symsrc__has_symtab(struct symsrc *ss) { return ss->symtab != NULL; diff --git a/tools/perf/util/symbol-minimal.c b/tools/perf/util/symbol-minimal.c index 7747ea6..6738ea1 100644 --- a/tools/perf/util/symbol-minimal.c +++ b/tools/perf/util/symbol-minimal.c @@ -260,6 +260,12 @@ out_close: return -1; } +bool symsrc__possibly_runtime(struct symsrc *ss __used) +{ + /* Assume all sym sources could be a runtime image. */ + return true; +} + bool symsrc__has_symtab(struct symsrc *ss __used) { return false; diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index 739e5a3..2293a4a 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -1026,11 +1026,12 @@ int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter) { char *name; int ret = -1; - struct symsrc ss; u_int i; struct machine *machine; char *root_dir = (char *) ""; - int want_symtab; + int ss_pos = 0; + struct symsrc ss_[2]; + struct symsrc *syms_ss = NULL, *runtime_ss = NULL; dso__set_loaded(dso, map->type); @@ -1072,12 +1073,12 @@ int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter) root_dir = machine->root_dir; /* Iterate over candidate debug images. - * On the first pass, only load images if they have a full symtab. - * Failing that, do a second pass where we accept .dynsym also + * Keep track of "interesting" ones (those which have a symtab, dynsym, + * and/or opd section) for processing. */ - want_symtab = 1; -restart: for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) { + struct symsrc *ss = &ss_[ss_pos]; + bool next_slot = false; enum dso_binary_type symtab_type = binary_type_symtab[i]; @@ -1086,45 +1087,55 @@ restart: continue; /* Name is now the name of the next image to try */ - if (symsrc__init(&ss, dso, name, symtab_type) < 0) + if (symsrc__init(ss, dso, name, symtab_type) < 0) continue; - if (want_symtab && !symsrc__has_symtab(&ss)) { - symsrc__destroy(&ss); - continue; + if (!syms_ss && symsrc__has_symtab(ss)) { + syms_ss = ss; + next_slot = true; } - ret = dso__load_sym(dso, map, &ss, &ss, filter, 0); - - /* - * Some people seem to have debuginfo files _WITHOUT_ debug - * info!?!? - */ - if (!ret) { - symsrc__destroy(&ss); - continue; + if (!runtime_ss && symsrc__possibly_runtime(ss)) { + runtime_ss = ss; + next_slot = true; } - if (ret > 0) { - int nr_plt; + if (next_slot) { + ss_pos++; - nr_plt = dso__synthesize_plt_symbols(dso, &ss, map, filter); - if (nr_plt > 0) - ret += nr_plt; - symsrc__destroy(&ss); - break; + if (syms_ss && runtime_ss) + break; } + } - /* - * If we wanted a full symtab but no image had one, - * relax our requirements and repeat the search. - */ - if (ret <= 0 && want_symtab) { - want_symtab = 0; - goto restart; + if (!runtime_ss && !syms_ss) + goto out_free; + + if (runtime_ss && !syms_ss) { + syms_ss = runtime_ss; + } + + /* We'll have to hope for the best */ + if (!runtime_ss && syms_ss) + runtime_ss = syms_ss; + + if (syms_ss) + ret = dso__load_sym(dso, map, syms_ss, runtime_ss, filter, 0); + else + ret = -1; + + if (ret > 0 && runtime_ss->dynsym) { + int nr_plt; + + nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss, map, filter); + if (nr_plt > 0) + ret += nr_plt; } + for (; ss_pos > 0; ss_pos--) + symsrc__destroy(&ss_[ss_pos - 1]); +out_free: free(name); if (ret < 0 && strstr(dso->name, " (deleted)") != NULL) return 0; diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h index 1f3eed2..fc4b1e6 100644 --- a/tools/perf/util/symbol.h +++ b/tools/perf/util/symbol.h @@ -253,6 +253,7 @@ void symsrc__destroy(struct symsrc *ss); int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name, enum dso_binary_type type); bool symsrc__has_symtab(struct symsrc *ss); +bool symsrc__possibly_runtime(struct symsrc *ss); #define DSO__SWAP(dso, type, val) \ ({ \ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
