From 4924734570a073049450b11f7c59ce5992b03343 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Tue, 5 Apr 2016 11:33:41 -0300 Subject: [PATCH] perf probe: Check if dwarf_getlocations() is available If not, tell the user that: config/Makefile:273: Old libdw.h, finding variables at given 'perf probe' point will not work, install elfutils-devel/libdw-dev >= 0.157 And return -ENOTSUPP in die_get_var_range(), failing features that need it, like the one pointed out above. This fixes the build on older systems, such as Ubuntu 12.04.5. Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Vinson Lee Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-9l7luqkq4gfnx7vrklkq4obs@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/build/Makefile.feature | 2 ++ tools/build/feature/Makefile | 4 ++++ tools/build/feature/test-all.c | 5 +++++ tools/build/feature/test-dwarf_getlocations.c | 12 ++++++++++++ tools/perf/config/Makefile | 6 ++++++ tools/perf/util/dwarf-aux.c | 9 +++++++++ 6 files changed, 38 insertions(+) create mode 100644 tools/build/feature/test-dwarf_getlocations.c diff --git a/tools/build/Makefile.feature b/tools/build/Makefile.feature index 6b7707270aa3..9f878619077a 100644 --- a/tools/build/Makefile.feature +++ b/tools/build/Makefile.feature @@ -30,6 +30,7 @@ endef FEATURE_TESTS_BASIC := \ backtrace \ dwarf \ + dwarf_getlocations \ fortify-source \ sync-compare-and-swap \ glibc \ @@ -78,6 +79,7 @@ endif FEATURE_DISPLAY ?= \ dwarf \ + dwarf_getlocations \ glibc \ gtk2 \ libaudit \ diff --git a/tools/build/feature/Makefile b/tools/build/feature/Makefile index c5f4c417428d..4ae94dbfdab9 100644 --- a/tools/build/feature/Makefile +++ b/tools/build/feature/Makefile @@ -3,6 +3,7 @@ FILES= \ test-backtrace.bin \ test-bionic.bin \ test-dwarf.bin \ + test-dwarf_getlocations.bin \ test-fortify-source.bin \ test-sync-compare-and-swap.bin \ test-glibc.bin \ @@ -82,6 +83,9 @@ endif $(OUTPUT)test-dwarf.bin: $(BUILD) $(DWARFLIBS) +$(OUTPUT)test-dwarf_getlocations.bin: + $(BUILD) $(DWARFLIBS) + $(OUTPUT)test-libelf-mmap.bin: $(BUILD) -lelf diff --git a/tools/build/feature/test-all.c b/tools/build/feature/test-all.c index e499a36c1e4a..a282e8cb84f3 100644 --- a/tools/build/feature/test-all.c +++ b/tools/build/feature/test-all.c @@ -41,6 +41,10 @@ # include "test-dwarf.c" #undef main +#define main main_test_dwarf_getlocations +# include "test-dwarf_getlocations.c" +#undef main + #define main main_test_libelf_getphdrnum # include "test-libelf-getphdrnum.c" #undef main @@ -143,6 +147,7 @@ int main(int argc, char *argv[]) main_test_libelf_mmap(); main_test_glibc(); main_test_dwarf(); + main_test_dwarf_getlocations(); main_test_libelf_getphdrnum(); main_test_libunwind(); main_test_libaudit(); diff --git a/tools/build/feature/test-dwarf_getlocations.c b/tools/build/feature/test-dwarf_getlocations.c new file mode 100644 index 000000000000..70162699dd43 --- /dev/null +++ b/tools/build/feature/test-dwarf_getlocations.c @@ -0,0 +1,12 @@ +#include +#include + +int main(void) +{ + Dwarf_Addr base, start, end; + Dwarf_Attribute attr; + Dwarf_Op *op; + size_t nops; + ptrdiff_t offset = 0; + return (int)dwarf_getlocations(&attr, offset, &base, &start, &end, &op, &nops); +} diff --git a/tools/perf/config/Makefile b/tools/perf/config/Makefile index f7d7f5a1cad5..6f8f6430f2bf 100644 --- a/tools/perf/config/Makefile +++ b/tools/perf/config/Makefile @@ -268,6 +268,12 @@ else ifneq ($(feature-dwarf), 1) msg := $(warning No libdw.h found or old libdw.h found or elfutils is older than 0.138, disables dwarf support. Please install new elfutils-devel/libdw-dev); NO_DWARF := 1 + else + ifneq ($(feature-dwarf_getlocations), 1) + msg := $(warning Old libdw.h, finding variables at given 'perf probe' point will not work, install elfutils-devel/libdw-dev >= 0.157); + else + CFLAGS += -DHAVE_DWARF_GETLOCATIONS + endif # dwarf_getlocations endif # Dwarf support endif # libelf support endif # NO_LIBELF diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c index 577e600c8eb1..aea189b41cc8 100644 --- a/tools/perf/util/dwarf-aux.c +++ b/tools/perf/util/dwarf-aux.c @@ -959,6 +959,7 @@ int die_get_varname(Dwarf_Die *vr_die, struct strbuf *buf) return 0; } +#ifdef HAVE_DWARF_GETLOCATIONS /** * die_get_var_innermost_scope - Get innermost scope range of given variable DIE * @sp_die: a subprogram DIE @@ -1080,3 +1081,11 @@ int die_get_var_range(Dwarf_Die *sp_die, Dwarf_Die *vr_die, struct strbuf *buf) return ret; } +#else +int die_get_var_range(Dwarf_Die *sp_die __maybe_unused, + Dwarf_Die *vr_die __maybe_unused, + struct strbuf *buf __maybe_unused) +{ + return -ENOTSUP; +} +#endif -- 2.20.1