From edd695b032ba3a90c3bb07d934500b2c390a61ff Mon Sep 17 00:00:00 2001 From: Wang Nan Date: Sat, 26 Nov 2016 07:03:39 +0000 Subject: perf clang: Compile BPF script using builtin clang support After this patch, perf utilizes builtin clang support to build BPF script, no longer depend on external clang, but fallbacking to it if for some reason the builtin compiling framework fails. Test: $ type clang -bash: type: clang: not found $ cat ~/.perfconfig $ echo '#define LINUX_VERSION_CODE 0x040700' > ./test.c $ cat ./tools/perf/tests/bpf-script-example.c >> ./test.c $ ./perf record -v --dry-run -e ./test.c 2>&1 | grep builtin bpf: successfull builtin compilation $ Can't pass cflags so unable to include kernel headers now. Will be fixed by following commits. Committer notes: Make sure '-v' comes before the '-e ./test.c' in the command line otherwise the 'verbose' variable will not be set when the bpf event is parsed and thus the pr_debug indicating a 'successfull builtin compilation' will not be output, as the debug level (1) will be less than what 'verbose' has at that point (0). Signed-off-by: Wang Nan Tested-by: Arnaldo Carvalho de Melo Cc: Alexei Starovoitov Cc: He Kuang Cc: Jiri Olsa Cc: Joe Stringer Cc: Zefan Li Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/20161126070354.141764-16-wangnan0@huawei.com [ Spell check/reflow successfull pr_debug string ] Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/bpf-loader.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) (limited to 'tools/perf/util/bpf-loader.c') diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c index cf16b94115b5..36c861103291 100644 --- a/tools/perf/util/bpf-loader.c +++ b/tools/perf/util/bpf-loader.c @@ -14,11 +14,11 @@ #include "debug.h" #include "bpf-loader.h" #include "bpf-prologue.h" -#include "llvm-utils.h" #include "probe-event.h" #include "probe-finder.h" // for MAX_PROBES #include "parse-events.h" #include "llvm-utils.h" +#include "c++/clang-c.h" #define DEFINE_PRINT_FN(name, level) \ static int libbpf_##name(const char *fmt, ...) \ @@ -86,9 +86,16 @@ struct bpf_object *bpf__prepare_load(const char *filename, bool source) void *obj_buf; size_t obj_buf_sz; - err = llvm__compile_bpf(filename, &obj_buf, &obj_buf_sz); - if (err) - return ERR_PTR(-BPF_LOADER_ERRNO__COMPILE); + perf_clang__init(); + err = perf_clang__compile_bpf(filename, &obj_buf, &obj_buf_sz); + perf_clang__cleanup(); + if (err) { + pr_warning("bpf: builtin compilation failed: %d, try external compiler\n", err); + err = llvm__compile_bpf(filename, &obj_buf, &obj_buf_sz); + if (err) + return ERR_PTR(-BPF_LOADER_ERRNO__COMPILE); + } else + pr_debug("bpf: successfull builtin compilation\n"); obj = bpf_object__open_buffer(obj_buf, obj_buf_sz, filename); if (!IS_ERR(obj) && llvm_param.dump_obj) -- cgit v1.2.3