[PATCH] perf: fix getting source line failure in annotate

From: Wei Li
Date: Thu Feb 21 2019 - 04:58:11 EST


The output of "perf annotate -l --stdio xxx" changed since commit 425859ff0de33 ("perf
annotate: No need to calculate notes->start twice") removed notes->start assignment
in symbol__calc_lines(). It will get failed in find_address_in_section() from
symbol__tty_annotate() subroutine as the a2l->addr is wrong. So the annotate summary
doesn't report the line number of source code correctly.

Before fix:

liwei@euler:~/main_code/hulk_work/hulk/tools/perf$ cat common_while_1.c
void hotspot_1(void)
{
volatile int i;

for (i = 0; i < 0x10000000; i++);
for (i = 0; i < 0x10000000; i++);
for (i = 0; i < 0x10000000; i++);
}

int main(void)
{
hotspot_1();

return 0;
}
liwei@euler:~/main_code/hulk_work/hulk/tools/perf$ gcc common_while_1.c -g -o common_while_1

liwei@euler:~/main_code/hulk_work/hulk/tools/perf$ sudo ./perf record ./common_while_1
[ perf record: Woken up 2 times to write data ]
[ perf record: Captured and wrote 0.488 MB perf.data (12498 samples) ]
liwei@euler:~/main_code/hulk_work/hulk/tools/perf$ sudo ./perf annotate -l -s hotspot_1 --stdio

Sorted summary for file /home/liwei/main_code/hulk_work/hulk/tools/perf/common_while_1
----------------------------------------------

19.30 common_while_1[32]
19.03 common_while_1[4e]
19.01 common_while_1[16]
5.04 common_while_1[13]
4.99 common_while_1[4b]
4.78 common_while_1[2c]
4.77 common_while_1[10]
4.66 common_while_1[2f]
4.59 common_while_1[51]
4.59 common_while_1[35]
4.52 common_while_1[19]
4.20 common_while_1[56]
0.51 common_while_1[48]
Percent | Source code & Disassembly of common_while_1 for cycles:ppp (12480 samples, percent: local period)
-----------------------------------------------------------------------------------------------------------------
:
:
:
: Disassembly of section .text:
:
: 00000000000005fa <hotspot_1>:
: hotspot_1():
: void hotspot_1(void)
: {
0.00 : 5fa: push %rbp
0.00 : 5fb: mov %rsp,%rbp
: volatile int i;
:
: for (i = 0; i < 0x10000000; i++);
0.00 : 5fe: movl $0x0,-0x4(%rbp)
0.00 : 605: jmp 610 <hotspot_1+0x16>
0.00 : 607: mov -0x4(%rbp),%eax
common_while_1[10] 4.77 : 60a: add $0x1,%eax
common_while_1[13] 5.04 : 60d: mov %eax,-0x4(%rbp)
common_while_1[16] 19.01 : 610: mov -0x4(%rbp),%eax
common_while_1[19] 4.52 : 613: cmp $0xfffffff,%eax
0.00 : 618: jle 607 <hotspot_1+0xd>
: for (i = 0; i < 0x10000000; i++);
...

After fix:

liwei@euler:~/main_code/hulk_work/hulk/tools/perf$ sudo ./perf record ./common_while_1
[ perf record: Woken up 2 times to write data ]
[ perf record: Captured and wrote 0.488 MB perf.data (12500 samples) ]
liwei@euler:~/main_code/hulk_work/hulk/tools/perf$ sudo ./perf annotate -l -s hotspot_1 --stdio

Sorted summary for file /home/liwei/main_code/hulk_work/hulk/tools/perf/common_while_1
----------------------------------------------

33.34 common_while_1.c:5
33.34 common_while_1.c:6
33.32 common_while_1.c:7
Percent | Source code & Disassembly of common_while_1 for cycles:ppp (12482 samples, percent: local period)
-----------------------------------------------------------------------------------------------------------------
:
:
:
: Disassembly of section .text:
:
: 00000000000005fa <hotspot_1>:
: hotspot_1():
: void hotspot_1(void)
: {
0.00 : 5fa: push %rbp
0.00 : 5fb: mov %rsp,%rbp
: volatile int i;
:
: for (i = 0; i < 0x10000000; i++);
0.00 : 5fe: movl $0x0,-0x4(%rbp)
0.00 : 605: jmp 610 <hotspot_1+0x16>
0.00 : 607: mov -0x4(%rbp),%eax
common_while_1.c:5 4.70 : 60a: add $0x1,%eax
4.89 : 60d: mov %eax,-0x4(%rbp)
common_while_1.c:5 19.03 : 610: mov -0x4(%rbp),%eax
common_while_1.c:5 4.72 : 613: cmp $0xfffffff,%eax
0.00 : 618: jle 607 <hotspot_1+0xd>
: for (i = 0; i < 0x10000000; i++);
0.00 : 61a: movl $0x0,-0x4(%rbp)
0.00 : 621: jmp 62c <hotspot_1+0x32>
0.00 : 623: mov -0x4(%rbp),%eax
common_while_1.c:6 4.54 : 626: add $0x1,%eax
4.73 : 629: mov %eax,-0x4(%rbp)
common_while_1.c:6 19.54 : 62c: mov -0x4(%rbp),%eax
common_while_1.c:6 4.54 : 62f: cmp $0xfffffff,%eax
...

Fixes: 425859ff0de33 ("perf annotate: No need to calculate notes->start twice")
Signed-off-by: Wei Li <liwei391@xxxxxxxxxx>
---
tools/perf/util/annotate.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index 70de8f6b3aee..9142fd294e76 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -1889,6 +1889,7 @@ int symbol__annotate(struct symbol *sym, struct map *map,
struct annotation_options *options,
struct arch **parch)
{
+ struct annotation *notes = symbol__annotation(sym);
struct annotate_args args = {
.privsize = privsize,
.evsel = evsel,
@@ -1919,6 +1920,7 @@ int symbol__annotate(struct symbol *sym, struct map *map,

args.ms.map = map;
args.ms.sym = sym;
+ notes->start = map__rip_2objdump(map, sym->start);

return symbol__disassemble(sym, &args);
}
@@ -2794,8 +2796,6 @@ int symbol__annotate2(struct symbol *sym, struct map *map, struct perf_evsel *ev

symbol__calc_percent(sym, evsel);

- notes->start = map__rip_2objdump(map, sym->start);
-
annotation__set_offsets(notes, size);
annotation__mark_jump_targets(notes, sym);
annotation__compute_ipc(notes, size);
--
2.17.1