Re: [PATCHv2 5/8] perf probe powerpc: Allow matching against dot symbols

2015-04-26 Thread Naveen N. Rao 
On 2015/03/12 05:30PM, Arnaldo Carvalho de Melo wrote:
 Em Mon, Dec 15, 2014 at 08:20:35PM +0530, Naveen N. Rao escreveu:
  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.
 
 This one looks better, does arch specific stuff in tools/perf/arch,
 good, some nits below.
 
  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 000..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
 
 
 Dunno about this naming, looks too general: SYMBOL_HANDLING, but can't
 come to some better one now, anyone?
 
   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 +,7 @@ static int probe_function_filter(struct map *map 
  __maybe_unused,
  }
  return 1;
   }
  +#endif /* HAVE_ARCH_SYMBOL_HANDLING */
 
 Can't we do something like providing a weak function and let the linked
 to its work? I guess we have cases like this in tools/ already. I.e. not
 using the ifndef block. Minor nit tho.

That sounds like a good idea. I will move these over to use __weak 
functions.

 
   
   #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

[PATCHv2 5/8] perf probe powerpc: Allow matching against dot symbols

2014-12-15 Thread Naveen N. Rao 
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 000..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 +,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_INDEX1024
 
-- 
2.1.3