[PATCHv2 5/8] perf probe powerpc: Allow matching against dot symbols
From: Naveen N. Rao <hidden>
Date: 2014-12-15 14:51:17
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 powerpc ABIv1 without the need to specify the leading dot '.' for functions. 'perf probe do_fork' works with this patch. Introduce HAVE_ARCH_SYMBOL_HANDLING to indicate need for special handling of symbols. In this patch, we override probe_function_filter() on powerpc to account for dot symbols. Signed-off-by: Naveen N. Rao <redacted> --- Changes from the previous patchset: Introduced arch helper to override the way probe function filter works. tools/perf/arch/powerpc/Makefile | 1 + tools/perf/arch/powerpc/util/sym-handling.c | 28 ++++++++++++++++++++++++++++ tools/perf/config/Makefile | 1 + tools/perf/util/probe-event.c | 10 +++++----- tools/perf/util/probe-event.h | 5 +++++ 5 files changed, 40 insertions(+), 5 deletions(-) create mode 100644 tools/perf/arch/powerpc/util/sym-handling.c
diff --git a/tools/perf/arch/powerpc/Makefile b/tools/perf/arch/powerpc/Makefile
index 6f7782b..1c3d435 100644
--- a/tools/perf/arch/powerpc/Makefile
+++ b/tools/perf/arch/powerpc/Makefile@@ -3,4 +3,5 @@ PERF_HAVE_DWARF_REGS := 1 LIB_OBJS += $(OUTPUT)arch/$(ARCH)/util/dwarf-regs.o LIB_OBJS += $(OUTPUT)arch/$(ARCH)/util/skip-callchain-idx.o endif +LIB_OBJS += $(OUTPUT)arch/$(ARCH)/util/sym-handling.o LIB_OBJS += $(OUTPUT)arch/$(ARCH)/util/header.o
diff --git a/tools/perf/arch/powerpc/util/sym-handling.c b/tools/perf/arch/powerpc/util/sym-handling.c
new file mode 100644
index 0000000..0a77825
--- /dev/null
+++ b/tools/perf/arch/powerpc/util/sym-handling.c@@ -0,0 +1,28 @@ +/* + * Special symbol handling for PowerPC: + * - Handle dot symbols on ABIv1 + * + * Copyright (C) 2014 Naveen N Rao, IBM Corporation. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include "map.h" +#include "symbol.h" +#include "probe-event.h" + +int probe_function_filter(struct map *map __maybe_unused, struct symbol *sym) +{ + if (sym->binding == STB_GLOBAL || sym->binding == STB_LOCAL) { + if ((strcmp(looking_function_name, sym->name) == 0) || + (sym->name[0] == '.' && looking_function_name[0] != '.' && + strcmp(looking_function_name, sym->name+1) == 0)) { + num_matched_functions++; + return 0; + } + } + return 1; +}
diff --git a/tools/perf/config/Makefile b/tools/perf/config/Makefile
index 5d4b039..35cf934 100644
--- a/tools/perf/config/Makefile
+++ b/tools/perf/config/Makefile@@ -383,6 +383,7 @@ ifeq ($(ARCH),powerpc) ifndef NO_DWARF CFLAGS += -DHAVE_SKIP_CALLCHAIN_IDX endif + CFLAGS += -DHAVE_ARCH_SYMBOL_HANDLING endif ifndef NO_LIBUNWIND
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 74b7fef..7eb9b27 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c@@ -50,6 +50,8 @@ #define PERFPROBE_GROUP "probe" bool probe_event_dry_run; /* Dry run flag */ +char *looking_function_name; +int num_matched_functions; #define semantic_error(msg ...) pr_err("Semantic error :" msg)
@@ -2210,11 +2212,8 @@ static int __add_probe_trace_events(struct perf_probe_event *pev, return ret; } -static char *looking_function_name; -static int num_matched_functions; - -static int probe_function_filter(struct map *map __maybe_unused, - struct symbol *sym) +#ifndef HAVE_ARCH_SYMBOL_HANDLING +int probe_function_filter(struct map *map __maybe_unused, struct symbol *sym) { if ((sym->binding == STB_GLOBAL || sym->binding == STB_LOCAL) && strcmp(looking_function_name, sym->name) == 0) {
@@ -2223,6 +2222,7 @@ static int probe_function_filter(struct map *map __maybe_unused, } return 1; } +#endif /* HAVE_ARCH_SYMBOL_HANDLING */ #define strdup_or_goto(str, label) \ ({ char *__p = strdup(str); if (!__p) goto label; __p; })
diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h
index e01e994..8564451 100644
--- a/tools/perf/util/probe-event.h
+++ b/tools/perf/util/probe-event.h@@ -7,6 +7,8 @@ #include "strfilter.h" extern bool probe_event_dry_run; +extern char *looking_function_name; +extern int num_matched_functions; /* kprobe-tracer and uprobe-tracer tracing point */ struct probe_trace_point {
@@ -136,6 +138,9 @@ extern int show_available_vars(struct perf_probe_event *pevs, int npevs, extern int show_available_funcs(const char *module, struct strfilter *filter, bool user); +extern int probe_function_filter(struct map *map __maybe_unused, + struct symbol *sym); + /* Maximum index number of event-name postfix */ #define MAX_EVENT_INDEX 1024
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2.1.3