[PATCH -tip 2/2] [BUGFIX] perf probe: Use origial address instead of CU-based address

Masami Hiramatsu
2010-03-15T16:54:31Z

Use original address for looking up the location of variables for
dwarf_getlocation_addr() instead of CU-based address.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
---

tools/perf/util/probe-finder.c | 11 ++---------
tools/perf/util/probe-finder.h | 1 -
2 files changed, 2 insertions(+), 10 deletions(-)

diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index 0e8c8f1..c171a24 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -352,8 +352,7 @@ static void show_variable(Dwarf_Die *vr_die, struct probe_finder *pf)
if (dwarf_attr(vr_die, DW_AT_location, &attr) == NULL)
goto error;
/* TODO: handle more than 1 exprs */
- ret = dwarf_getlocation_addr(&attr, (pf->addr - pf->cu_base),
- &expr, &nexpr, 1);
+ ret = dwarf_getlocation_addr(&attr, pf->addr, &expr, &nexpr, 1);
if (ret <= 0 || nexpr == 0)
goto error;

@@ -437,8 +436,7 @@ static void show_probe_point(Dwarf_Die *sp_die, struct probe_finder *pf)

/* Get the frame base attribute/ops */
dwarf_attr(sp_die, DW_AT_frame_base, &fb_attr);
- ret = dwarf_getlocation_addr(&fb_attr, (pf->addr - pf->cu_base),
- &pf->fb_ops, &nops, 1);
+ ret = dwarf_getlocation_addr(&fb_attr, pf->addr, &pf->fb_ops, &nops, 1);
if (ret <= 0 || nops == 0)
pf->fb_ops = NULL;

@@ -644,7 +642,6 @@ static void find_probe_point_by_func(struct probe_finder *pf)
int find_probe_point(int fd, struct probe_point *pp)
{
struct probe_finder pf = {.pp = pp};
- int ret;
Dwarf_Off off, noff;
size_t cuhl;
Dwarf_Die *diep;
@@ -671,10 +668,6 @@ int find_probe_point(int fd, struct probe_point *pp)
pf.fname = NULL;

if (!pp->file || pf.fname) {
- /* Save CU base address (for frame_base) */
- ret = dwarf_lowpc(&pf.cu_die, &pf.cu_base);
- if (ret != 0)
- pf.cu_base = 0;
if (pp->function)
find_probe_point_by_func(&pf);
else if (pp->lazy_line)
diff --git a/tools/perf/util/probe-finder.h b/tools/perf/util/probe-finder.h
index d1a6517..21f7354 100644
--- a/tools/perf/util/probe-finder.h
+++ b/tools/perf/util/probe-finder.h
@@ -71,7 +71,6 @@ struct probe_finder {

/* For variable searching */
Dwarf_Op *fb_ops; /* Frame base attribute */
- Dwarf_Addr cu_base; /* Current CU base address */
const char *var; /* Current variable name */
char *buf; /* Current output buffer */
int len; /* Length of output buffer */

--
Masami Hiramatsu
e-mail: mhiramat@redhat.com