[tip:perf/core] perf build: Add feature detection for libelf's elf_getshdrstrndx()
From: tip-bot for Arnaldo Carvalho de Melo
Date: Tue Jul 05 2016 - 06:19:04 EST
Commit-ID: 2492c465ad3ae6860ebfff1c9032865017835e70
Gitweb: http://git.kernel.org/tip/2492c465ad3ae6860ebfff1c9032865017835e70
Author: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
AuthorDate: Mon, 4 Jul 2016 19:35:47 -0300
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Mon, 4 Jul 2016 19:38:59 -0300
perf build: Add feature detection for libelf's elf_getshdrstrndx()
That appeared after 0.140, and will be used in the SDT code, so, to
avoid bisection break on older systems, add a feature detection and
provide a stub with a pr_debug() to keep it building.
Cc: Ananth N Mavinakayanahalli <ananth@xxxxxxxxxxxxxxxxxx>
Cc: Brendan Gregg <brendan.d.gregg@xxxxxxxxx>
Cc: Hemant Kumar <hemant@xxxxxxxxxxxxxxxxxx>
Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/n/tip-80y0eldgweorqnwha9rvfxjr@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/build/Makefile.feature | 1 +
tools/build/feature/Makefile | 4 ++++
tools/build/feature/test-all.c | 5 +++++
.../{test-libelf-getphdrnum.c => test-libelf-getshdrstrndx.c} | 2 +-
tools/perf/config/Makefile | 4 ++++
tools/perf/util/symbol-elf.c | 8 ++++++++
6 files changed, 23 insertions(+), 1 deletion(-)
diff --git a/tools/build/Makefile.feature b/tools/build/Makefile.feature
index 57c8f98..3dd529b 100644
--- a/tools/build/Makefile.feature
+++ b/tools/build/Makefile.feature
@@ -40,6 +40,7 @@ FEATURE_TESTS_BASIC := \
libbfd \
libelf \
libelf-getphdrnum \
+ libelf-getshdrstrndx \
libelf-mmap \
libnuma \
numa_num_possible_cpus \
diff --git a/tools/build/feature/Makefile b/tools/build/feature/Makefile
index 3d88f09..6747116 100644
--- a/tools/build/feature/Makefile
+++ b/tools/build/feature/Makefile
@@ -17,6 +17,7 @@ FILES= \
test-cplus-demangle.bin \
test-libelf.bin \
test-libelf-getphdrnum.bin \
+ test-libelf-getshdrstrndx.bin \
test-libelf-mmap.bin \
test-libnuma.bin \
test-numa_num_possible_cpus.bin \
@@ -98,6 +99,9 @@ $(OUTPUT)test-libelf-mmap.bin:
$(OUTPUT)test-libelf-getphdrnum.bin:
$(BUILD) -lelf
+$(OUTPUT)test-libelf-getshdrstrndx.bin:
+ $(BUILD) -lelf
+
$(OUTPUT)test-libnuma.bin:
$(BUILD) -lnuma
diff --git a/tools/build/feature/test-all.c b/tools/build/feature/test-all.c
index a282e8c..7433cca 100644
--- a/tools/build/feature/test-all.c
+++ b/tools/build/feature/test-all.c
@@ -49,6 +49,10 @@
# include "test-libelf-getphdrnum.c"
#undef main
+#define main main_test_libelf_getshdrstrndx
+# include "test-libelf-getshdrstrndx.c"
+#undef main
+
#define main main_test_libunwind
# include "test-libunwind.c"
#undef main
@@ -149,6 +153,7 @@ int main(int argc, char *argv[])
main_test_dwarf();
main_test_dwarf_getlocations();
main_test_libelf_getphdrnum();
+ main_test_libelf_getshdrstrndx();
main_test_libunwind();
main_test_libaudit();
main_test_libslang();
diff --git a/tools/build/feature/test-libelf-getphdrnum.c b/tools/build/feature/test-libelf-getshdrstrndx.c
similarity index 60%
copy from tools/build/feature/test-libelf-getphdrnum.c
copy to tools/build/feature/test-libelf-getshdrstrndx.c
index d710459..f0c3b47 100644
--- a/tools/build/feature/test-libelf-getphdrnum.c
+++ b/tools/build/feature/test-libelf-getshdrstrndx.c
@@ -4,5 +4,5 @@ int main(void)
{
size_t dst;
- return elf_getphdrnum(0, &dst);
+ return elf_getshdrstrndx(0, &dst);
}
diff --git a/tools/perf/config/Makefile b/tools/perf/config/Makefile
index bf1a0a0..c7e269a 100644
--- a/tools/perf/config/Makefile
+++ b/tools/perf/config/Makefile
@@ -309,6 +309,10 @@ ifndef NO_LIBELF
CFLAGS += -DHAVE_ELF_GETPHDRNUM_SUPPORT
endif
+ ifeq ($(feature-libelf-getshdrstrndx), 1)
+ CFLAGS += -DHAVE_ELF_GETSHDRSTRNDX_SUPPORT
+ endif
+
ifndef NO_DWARF
ifeq ($(origin PERF_HAVE_DWARF_REGS), undefined)
msg := $(warning DWARF register mappings have not been defined for architecture $(ARCH), DWARF support disabled);
diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
index 87a297d..b222552c 100644
--- a/tools/perf/util/symbol-elf.c
+++ b/tools/perf/util/symbol-elf.c
@@ -54,6 +54,14 @@ static int elf_getphdrnum(Elf *elf, size_t *dst)
}
#endif
+#ifndef HAVE_ELF_GETSHDRSTRNDX_SUPPORT
+static int elf_getshdrstrndx(Elf *elf __maybe_unused, size_t *dst __maybe_unused)
+{
+ pr_err("%s: update your libelf to > 0.140, this one lacks elf_getshdrstrndx().\n", __func__);
+ return -1;
+}
+#endif
+
#ifndef NT_GNU_BUILD_ID
#define NT_GNU_BUILD_ID 3
#endif