[PATCH v3 4/7] perf probe/ppc: Enable matching against dot symbols automatically
From: Naveen N. Rao <hidden>
Date: 2015-04-28 12:06:31
Also in:
lkml
Subsystem:
performance events subsystem, the rest · Maintainers:
Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Namhyung Kim, Linus Torvalds
Allow perf probe to work on ppc ABIv1 without the need to specify the leading dot '.' for functions. 'perf probe do_fork' works with this patch. We do this by changing how symbol name comparison works on ppc ABIv1 - we simply ignore and skip over the initial dot, if one exists, during symbol name comparison. Signed-off-by: Naveen N. Rao <redacted> Reviewed-by: Srikar Dronamraju <redacted> --- Changes: This patch has been redone since upstream changed quite a bit. We now implement arch-specific helper during symbol name comparison to ignore leading dot on ppc symbols. tools/perf/arch/powerpc/util/sym-handling.c | 13 +++++++++++++ tools/perf/util/map.c | 5 +++++ tools/perf/util/map.h | 3 ++- tools/perf/util/symbol.c | 4 ++-- 4 files changed, 22 insertions(+), 3 deletions(-)
diff --git a/tools/perf/arch/powerpc/util/sym-handling.c b/tools/perf/arch/powerpc/util/sym-handling.c
index 5522a40..2de2cc4 100644
--- a/tools/perf/arch/powerpc/util/sym-handling.c
+++ b/tools/perf/arch/powerpc/util/sym-handling.c@@ -8,6 +8,7 @@ #include "debug.h" #include "symbol.h" +#include "map.h" #ifdef HAVE_LIBELF_SUPPORT bool elf__needs_adjust_symbols(GElf_Ehdr ehdr)
@@ -36,4 +37,16 @@ int arch__choose_best_symbol(struct symbol *syma, return SYMBOL_A; } + +/* Allow matching against dot variants */ +int arch__compare_symbol_names(const char *namea, const char *nameb) +{ + /* Skip over initial dot */ + if (*namea == '.') + namea++; + if (*nameb == '.') + nameb++; + + return strcmp(namea, nameb); +} #endif
diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c
index a14f08f..cd0e335 100644
--- a/tools/perf/util/map.c
+++ b/tools/perf/util/map.c@@ -292,6 +292,11 @@ int map__load(struct map *map, symbol_filter_t filter) return 0; } +int __weak arch__compare_symbol_names(const char *namea, const char *nameb) +{ + return strcmp(namea, nameb); +} + struct symbol *map__find_symbol(struct map *map, u64 addr, symbol_filter_t filter) {
diff --git a/tools/perf/util/map.h b/tools/perf/util/map.h
index ec19c59..4e0c729 100644
--- a/tools/perf/util/map.h
+++ b/tools/perf/util/map.h@@ -124,7 +124,7 @@ struct thread; */ #define __map__for_each_symbol_by_name(map, sym_name, pos, filter) \ for (pos = map__find_symbol_by_name(map, sym_name, filter); \ - pos && strcmp(pos->name, sym_name) == 0; \ + pos && arch__compare_symbol_names(pos->name, sym_name) == 0; \ pos = symbol__next_by_name(pos)) #define map__for_each_symbol_by_name(map, sym_name, pos) \
@@ -132,6 +132,7 @@ struct thread; typedef int (*symbol_filter_t)(struct map *map, struct symbol *sym); +int arch__compare_symbol_names(const char *namea, const char *nameb); void map__init(struct map *map, enum map_type type, u64 start, u64 end, u64 pgoff, struct dso *dso); struct map *map__new(struct machine *machine, u64 start, u64 len,
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index f805757..45ba48a 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c@@ -411,7 +411,7 @@ static struct symbol *symbols__find_by_name(struct rb_root *symbols, int cmp; s = rb_entry(n, struct symbol_name_rb_node, rb_node); - cmp = strcmp(name, s->sym.name); + cmp = arch__compare_symbol_names(name, s->sym.name); if (cmp < 0) n = n->rb_left;
@@ -429,7 +429,7 @@ static struct symbol *symbols__find_by_name(struct rb_root *symbols, struct symbol_name_rb_node *tmp; tmp = rb_entry(n, struct symbol_name_rb_node, rb_node); - if (strcmp(tmp->sym.name, s->sym.name)) + if (arch__compare_symbol_names(tmp->sym.name, s->sym.name)) break; s = tmp;
--
2.3.5