Commit 0104fe69 authored Mar 02, 2015 by Masami Hiramatsu Committed by Arnaldo Carvalho de Melo Mar 02, 2015

perf probe: Remove bias offset to find probe point by address



Remove bias offset to find probe point by address.

Without this patch, probe points on kernel and executables are shown
correctly, but do not work with libraries:

  # ./perf probe -l
    probe:do_fork        (on do_fork@kernel/fork.c)
    probe_libc:malloc    (on malloc in /usr/lib64/libc-2.17.so)
    probe_perf:strlist__new (on strlist__new@util/strlist.c in /home/mhiramat/ksrc/linux-3/tools/perf/perf)

Removing bias allows it to show it as real place:

  # ./perf probe -l
    probe:do_fork        (on do_fork@kernel/fork.c)
    probe_libc:malloc    (on __libc_malloc@malloc/malloc.c in /usr/lib64/libc-2.17.so)
    probe_perf:strlist__new (on strlist__new@util/strlist.c in /home/mhiramat/ksrc/linux-3/tools/perf/perf)

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150302124946.9191.64085.stgit@localhost.localdomain


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

parent 79702f61

tools/perf/util/probe-finder.c

+1 −4

Original line number	Diff line number	Diff line
		@@ -1345,11 +1345,8 @@ int debuginfo__find_probe_point(struct debuginfo *dbg, unsigned long addr,
		const char fname = NULL, func = NULL, basefunc = NULL, tmp;
		int baseline = 0, lineno = 0, ret = 0;

		/* Adjust address with bias */
		addr += dbg->bias;

		/* Find cu die */
		if (!dwarf_addrdie(dbg->dbg, (Dwarf_Addr)addr - dbg->bias, &cudie)) {
		if (!dwarf_addrdie(dbg->dbg, (Dwarf_Addr)addr, &cudie)) {
		pr_warning("Failed to find debug information for address %lx\n",
		addr);
		ret = -EINVAL;