Merge commit 'v2.6.32-rc6' into perf/core

Conflicts:
	tools/perf/Makefile

Merge reason: Resolve the conflict, merge to upstream and merge in
              perf fixes so we can add a dependent patch.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

3 files changed, 20 insertions, 11 deletions

diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index 9f4488d6f8e6..542b29e2e382 100644
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -177,8 +177,7 @@ endif
 # Include saner warnings here, which can catch bugs:
 #
 
-EXTRA_WARNINGS := -Wcast-align
-EXTRA_WARNINGS := $(EXTRA_WARNINGS) -Wformat
+EXTRA_WARNINGS := -Wformat
 EXTRA_WARNINGS := $(EXTRA_WARNINGS) -Wformat-security
 EXTRA_WARNINGS := $(EXTRA_WARNINGS) -Wformat-y2k
 EXTRA_WARNINGS := $(EXTRA_WARNINGS) -Wshadow
@@ -456,12 +455,12 @@ ifeq ($(uname_S),Darwin)
 	PTHREAD_LIBS =
 endif
 
-ifneq ($(shell sh -c "(echo '\#include <gnu/libc-version.h>'; echo 'int main(void) { const char * version = gnu_get_libc_version(); return (long)version; }') | $(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)
-	msg := $(error No gnu/libc-version.h found, please install glibc-dev[el]);
-endif
-
-ifneq ($(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)
-	msg := $(error No libelf.h/libelf found, please install libelf-dev/elfutils-libelf-devel);
+ifeq ($(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
 
 ifdef NO_DEMANGLE
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 93c49f4685ff..ac94d7b94f61 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -549,7 +549,7 @@ static int dso__synthesize_plt_symbols(struct  dso *self)
 	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;
 
@@ -673,7 +673,7 @@ static int dso__load_sym(struct dso *self, struct map *map, const char *name,
 	Elf *elf;
 	int nr = 0;
 
-	elf = elf_begin(fd, ELF_C_READ_MMAP, NULL);
+	elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
 	if (elf == NULL) {
 		pr_err("%s: cannot read %s ELF file.\n", __func__, name);
 		goto out_close;
@@ -842,7 +842,7 @@ static char *dso__read_build_id(struct dso *self)
 	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) {
 		pr_err("%s: cannot read %s ELF file.\n", __func__,
 		       self->long_name);
diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
index a471a3840736..088433062dd4 100644
--- a/tools/perf/util/symbol.h
+++ b/tools/perf/util/symbol.h
@@ -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 */