From a09935b878dc8efd4b030ed1ffa0553fc9011fb8 Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Wed, 31 May 2017 21:01:05 +0900 Subject: perf symbols: Use correct filename for compressed modules in build-id cache The decompress_kmodule() decompresses kernel modules in order to load symbols from it. In the DSO_BINARY_TYPE__BUILD_ID_CACHE case, it needs the full file path to extract the file extension to determine the decompression method. But overwriting 'name' will fail the decompression since it might point to a non-existing old file. Instead, use dso->long_name for having the correct extension and use the real filename to decompress. In the DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP case, both names should be the same. This allows resolving symbols in the old modules. Before: $ perf report -i perf.data.old | grep scsi_mod 0.00% cc1 [scsi_mod] [k] 0x0000000000004aa6 0.00% as [scsi_mod] [k] 0x00000000000099e1 0.00% cc1 [scsi_mod] [k] 0x0000000000009830 0.00% cc1 [scsi_mod] [k] 0x0000000000001b8f After: 0.00% cc1 [scsi_mod] [k] scsi_handle_queue_ramp_up 0.00% as [scsi_mod] [k] scsi_sg_alloc 0.00% cc1 [scsi_mod] [k] scsi_setup_cmnd 0.00% cc1 [scsi_mod] [k] scsi_get_command Signed-off-by: Namhyung Kim Acked-by: Jiri Olsa Cc: Andi Kleen Cc: David Ahern Cc: Peter Zijlstra Cc: kernel-team@lge.com Link: http://lkml.kernel.org/r/20170531120105.21731-3-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/symbol-elf.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) (limited to 'tools/perf/util/symbol-elf.c') diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c index e7ee47f7377a..1fb2efae4f02 100644 --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -649,10 +649,7 @@ static int decompress_kmodule(struct dso *dso, const char *name, type != DSO_BINARY_TYPE__BUILD_ID_CACHE) return -1; - if (type == DSO_BINARY_TYPE__BUILD_ID_CACHE) - name = dso->long_name; - - if (kmod_path__parse_ext(&m, name) || !m.comp) + if (kmod_path__parse_ext(&m, dso->long_name) || !m.comp) return -1; fd = mkstemp(tmpbuf); -- cgit v1.2.3-59-g8ed1b