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