Commit 696b97a5 authored Aug 09, 2010 by Dave Martin Committed by Arnaldo Carvalho de Melo Aug 10, 2010

perf symbols: Ignore mapping symbols on ARM



ARM ELF files use symbols with special names $a, $t, $d to identify regions of
ARM code, Thumb code and data within code sections.  This can cause confusing
output from the perf tools, especially for partially stripped binaries, or
binaries containing user-added zero-sized symbols (which may occur in
hand-written assembler which hasn't been fully annotated with .size
directives).

This patch filters out these symbols at load time.

LKML-Reference: <1281352878-8735-2-git-send-email-dave.martin@linaro.org>
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

parent b1b02673

tools/perf/util/symbol.c

+10 −0

Original line number	Diff line number	Diff line
		@@ -1079,6 +1079,16 @@ static int dso__load_sym(struct dso self, struct map map, const char *name,
		if (!is_label && !elf_sym__is_a(&sym, map->type))
		continue;

		/* Reject ARM ELF "mapping symbols": these aren't unique and
		* don't identify functions, so will confuse the profile
		* output: */
		if (ehdr.e_machine == EM_ARM) {
		if (!strcmp(elf_name, "$a") \|\|
		!strcmp(elf_name, "$d") \|\|
		!strcmp(elf_name, "$t"))
		continue;
		}

		if (opdsec && sym.st_shndx == opdidx) {
		u32 offset = sym.st_value - opdshdr.sh_addr;
		u64 *opd = opddata->d_buf + offset;

Admin message