[PATCH v6 6/6] perf util: use correct IP mapping to find srcline for hist entry

From: Milian Wolff
Date: Wed Oct 18 2017 - 14:54:18 EST


When inline frame resolution is disabled, a bogus srcline is obtained
for hist entries:

~~~~~
$ perf report -s sym,srcline --no-inline --stdio -g none
95.21% 0.00% [.] __libc_start_main __libc_start_main+18446603358170398953
95.21% 0.00% [.] _start _start+18446650082411225129
46.67% 0.00% [.] main main+18446650082411225208
38.75% 0.00% [.] hypot hypot+18446603358164312084
23.75% 0.00% [.] main main+18446650082411225151
20.83% 20.83% [.] std::generate_canonical<double, 53ul, std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> > random.h:143
18.12% 0.00% [.] main main+18446650082411225165
13.12% 13.12% [.] std::generate_canonical<double, 53ul, std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> > random.tcc:3330
4.17% 4.17% [.] __hypot_finite __hypot_finite+163
4.17% 4.17% [.] std::generate_canonical<double, 53ul, std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> > random.tcc:3333
4.17% 0.00% [.] __hypot_finite __hypot_finite+18446603358164312227
4.17% 0.00% [.] std::generate_canonical<double, 53ul, std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> > std::generate_canonical<double, 53ul, std::line
2.92% 0.00% [.] std::generate_canonical<double, 53ul, std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> > std::generate_canonical<double, 53ul, std::line
2.50% 2.50% [.] __hypot_finite __hypot_finite+11
2.50% 2.50% [.] __hypot_finite __hypot_finite+24
2.50% 0.00% [.] __hypot_finite __hypot_finite+18446603358164312075
2.50% 0.00% [.] __hypot_finite __hypot_finite+18446603358164312088
~~~~~

Note how we get very large offsets to main and cannot see any srcline
from one of the complex or random headers, even though the instruction
pointers actually lie in code inlined from there.

This patch fixes the mapping to use map__objdump_2mem instead of
map__objdump_2mem in hist_entry__get_srcline. This fixes the srcline
values for me when inline resolution is disabled:

~~~~~
$ perf report -s sym,srcline --no-inline --stdio -g none
95.21% 0.00% [.] __libc_start_main __libc_start_main+233
95.21% 0.00% [.] _start _start+41
46.88% 0.00% [.] main complex:589
43.96% 0.00% [.] main random.h:185
38.75% 0.00% [.] hypot hypot+20
20.83% 0.00% [.] std::generate_canonical<double, 53ul, std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> > random.h:143
13.12% 0.00% [.] std::generate_canonical<double, 53ul, std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> > random.tcc:3330
4.17% 4.17% [.] __hypot_finite __hypot_finite+140715545239715
4.17% 4.17% [.] std::generate_canonical<double, 53ul, std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> > std::generate_canonical<double, 53ul, std::line
4.17% 0.00% [.] __hypot_finite __hypot_finite+163
4.17% 0.00% [.] std::generate_canonical<double, 53ul, std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> > random.tcc:3333
2.92% 2.92% [.] std::generate_canonical<double, 53ul, std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> > std::generate_canonical<double, 53ul, std::line
2.50% 2.50% [.] __hypot_finite __hypot_finite+140715545239563
2.50% 2.50% [.] __hypot_finite __hypot_finite+140715545239576
2.50% 2.50% [.] std::generate_canonical<double, 53ul, std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> > std::generate_canonical<double, 53ul, std::line
2.50% 2.50% [.] std::generate_canonical<double, 53ul, std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> > std::generate_canonical<double, 53ul, std::line
2.50% 0.00% [.] __hypot_finite __hypot_finite+11
~~~~~

Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Yao Jin <yao.jin@xxxxxxxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Signed-off-by: Milian Wolff <milian.wolff@xxxxxxxx>

Note how most of the large offset values are now gone. Most notably,
we get proper srcline resolution for the random.h and complex headers.
---
tools/perf/util/sort.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/sort.c b/tools/perf/util/sort.c
index 006d10a0dc96..6f3d109078a3 100644
--- a/tools/perf/util/sort.c
+++ b/tools/perf/util/sort.c
@@ -334,7 +334,7 @@ char *hist_entry__get_srcline(struct hist_entry *he)
if (!map)
return SRCLINE_UNKNOWN;

- return get_srcline(map->dso, map__rip_2objdump(map, he->ip),
+ return get_srcline(map->dso, map__objdump_2mem(map, he->ip),
he->ms.sym, true, true);
}

--
2.14.2