perf probe: Check if dwarf_getlocations() is available
tip-bot for Arnaldo Carvalho de Melo
merge botCommit-ID: bd0419e2a5a9fd9396cb7dc69044f961f52e19f0 Gitweb: http://git.kernel.org/tip/bd0419e2a5a9fd9396cb7dc69044f961f52e19f0 Author: Arnaldo Carvalho de Melo <[email protected]> AuthorDate: Tue, 5 Apr 2016 11:33:41 -0300 Committer: Arnaldo Carvalho de Melo <[email protected]> CommitDate: Wed, 6 Apr 2016 10:44:28 -0300
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 <[email protected]>
Cc David Ahern <[email protected]>
Cc Jiri Olsa <[email protected]>
Cc Namhyung Kim <[email protected]>
Cc Vinson Lee <[email protected]>
Cc Wang Nan <[email protected]>
Signed-off-by Arnaldo Carvalho de Melo <[email protected]>
--- 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(+)
tools/build/Makefile.feature +2 -0
@@ -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 \
tools/build/feature/Makefile +4 -0
@@ -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: $(BUILD) -lelf
tools/build/feature/test-all.c +5 -0
@@ -41,6 +41,10 @@# include "test-dwarf.c" #undef main +#define main main_test_dwarf_getlocations +# include "test-dwarf_getlocations.c" +#undef main +#define main main_test_libelf_getphdrnum# include "test-libelf-getphdrnum.c" #undef main
@@ -143,6 +147,7 @@ int main(int argc, char *argv[])main_test_libelf_mmap ();main_test_glibc ();main_test_dwarf (); +main_test_dwarf_getlocations ();main_test_libelf_getphdrnum ();main_test_libunwind ();main_test_libaudit ();
tools/build/feature/test-dwarf_getlocations.c new file +12 -0
@@ -0,0 +1,12 @@ +#include <stdlib.h> +#include <elfutils/libdw.h> + +int main (void ) +{ +Dwarf_Addr base, start, end; +Dwarf_Attribute attr; +Dwarf_Op *op; +size_t nops; +ptrdiff_t offset =0 ; +return (int )dwarf_getlocations (&attr, offset, &base, &start, &end, &op, &nops); +}
tools/perf/config/Makefile +6 -0
@@ -268,6 +268,12 @@ else ifneq ($(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
tools/perf/util/dwarf-aux.c +9 -0
@@ -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