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 <naveen.n....@linux.vnet.ibm.com>
---
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
--
2.1.3
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