Commit 84087126 authored by Marti Raudsepp's avatar Marti Raudsepp Committed by Ingo Molnar
Browse files

perf tools: Fix compatibility with libelf 0.8 and autodetect 



The Makefile now automatically defines LIBELF_NO_MMAP when
libelf 0.8.x is detected. libelf 0.8 is still maintained and
some distributions such as Arch Linux use it instead of
elfutils.

Signed-off-by: default avatarMarti Raudsepp <marti@juffo.org>
Cc: Lucas De Marchi <lucas.de.marchi@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1256400636.3007.16.camel@newn>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 54f44076

tools/perf/Makefile

+5 −1
Original line number Diff line number Diff line
@@ -422,7 +422,11 @@ ifeq ($(uname_S),Darwin) 
	PTHREAD_LIBS =

endif



ifeq ($(shell sh -c "(echo '\#include <libelf.h>'; echo 'int main(void) { Elf * elf = elf_begin(0, ELF_C_READ, 0); return (long)elf; }') | $(CC) -x c - $(ALL_CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -o /dev/null $(ALL_LDFLAGS) > /dev/null 2>&1 && echo y"), y)

	ifneq ($(shell sh -c "(echo '\#include <libelf.h>'; echo 'int main(void) { Elf * elf = elf_begin(0, ELF_C_READ_MMAP, 0); return (long)elf; }') | $(CC) -x c - $(ALL_CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -o /dev/null $(ALL_LDFLAGS) > /dev/null 2>&1 && echo y"), y)

		BASIC_CFLAGS += -DLIBELF_NO_MMAP

	endif

else

	msg := $(error No libelf.h/libelf found, please install libelf-dev/elfutils-libelf-devel and glibc-dev[el]);

endif

tools/perf/util/symbol.c

+3 −3
Original line number Diff line number Diff line
@@ -413,7 +413,7 @@ static int dso__synthesize_plt_symbols(struct dso *self, int v) 
	if (fd < 0)

		goto out;



	elf = elf_begin(fd, ELF_C_READ_MMAP, NULL);

	elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);

	if (elf == NULL)

		goto out_close;
@@ -533,7 +533,7 @@ static int dso__load_sym(struct dso *self, int fd, const char *name, 
	Elf *elf;

	int nr = 0, kernel = !strcmp("[kernel]", self->name);



	elf = elf_begin(fd, ELF_C_READ_MMAP, NULL);

	elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);

	if (elf == NULL) {

		if (v)

			fprintf(stderr, "%s: cannot read %s ELF file.\n",
@@ -675,7 +675,7 @@ static char *dso__read_build_id(struct dso *self, int v) 
	if (fd < 0)

		goto out;



	elf = elf_begin(fd, ELF_C_READ_MMAP, NULL);

	elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);

	if (elf == NULL) {

		if (v)

			fprintf(stderr, "%s: cannot read %s ELF file.\n",

tools/perf/util/symbol.h

+10 −0
Original line number Diff line number Diff line
@@ -27,6 +27,16 @@ static inline char *bfd_demangle(void __used *v, const char __used *c, 
#endif

#endif



/*

 * libelf 0.8.x and earlier do not support ELF_C_READ_MMAP;

 * for newer versions we can use mmap to reduce memory usage:

 */

#ifdef LIBELF_NO_MMAP

# define PERF_ELF_C_READ_MMAP ELF_C_READ

#else

# define PERF_ELF_C_READ_MMAP ELF_C_READ_MMAP

#endif



#ifndef DMGL_PARAMS

#define DMGL_PARAMS      (1 << 0)       /* Include function args */

#define DMGL_ANSI        (1 << 1)       /* Include const, volatile, etc */

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