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Subject[PATCH v3 1/2] perf util: Print al_addr when symbol is not found
Date
For branch mode, if the symbol is not found, it prints
the address.

For example, 0x0000555eee0365a0 in below output.

Overhead Command Source Shared Object Source Symbol Target Symbol
17.55% div libc-2.27.so [.] __random [.] __random
6.11% div div [.] 0x0000555eee0365a0 [.] rand
6.10% div libc-2.27.so [.] rand [.] 0x0000555eee036769
5.80% div libc-2.27.so [.] __random_r [.] __random
5.72% div libc-2.27.so [.] __random [.] __random_r
5.62% div libc-2.27.so [.] __random_r [.] __random_r
5.38% div libc-2.27.so [.] __random [.] rand
4.56% div libc-2.27.so [.] __random [.] __random
4.49% div div [.] 0x0000555eee036779 [.] 0x0000555eee0365ff
4.25% div div [.] 0x0000555eee0365fa [.] 0x0000555eee036760

But it's not very easy to understand what the instructions
are in the binary. So this patch uses the al_addr instead.

With this patch, the output is

Overhead Command Source Shared Object Source Symbol Target Symbol
17.55% div libc-2.27.so [.] __random [.] __random
6.11% div div [.] 0x00000000000005a0 [.] rand
6.10% div libc-2.27.so [.] rand [.] 0x0000000000000769
5.80% div libc-2.27.so [.] __random_r [.] __random
5.72% div libc-2.27.so [.] __random [.] __random_r
5.62% div libc-2.27.so [.] __random_r [.] __random_r
5.38% div libc-2.27.so [.] __random [.] rand
4.56% div libc-2.27.so [.] __random [.] __random
4.49% div div [.] 0x0000000000000779 [.] 0x00000000000005ff
4.25% div div [.] 0x00000000000005fa [.] 0x0000000000000760

Now we can use objdump to dump the object starting from 0x5a0.

For example,
objdump -d --start-address 0x5a0 div

00000000000005a0 <rand@plt>:
5a0: ff 25 2a 0a 20 00 jmpq *0x200a2a(%rip) # 200fd0 <__cxa_finalize@plt+0x200a20>
5a6: 68 02 00 00 00 pushq $0x2
5ab: e9 c0 ff ff ff jmpq 570 <srand@plt-0x10>
...

v2:
---
No change

Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
---
tools/perf/util/sort.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/sort.c b/tools/perf/util/sort.c
index ab0cfd790ad0..e860595576c2 100644
--- a/tools/perf/util/sort.c
+++ b/tools/perf/util/sort.c
@@ -869,7 +869,8 @@ static int hist_entry__sym_from_snprintf(struct hist_entry *he, char *bf,
if (he->branch_info) {
struct addr_map_symbol *from = &he->branch_info->from;

- return _hist_entry__sym_snprintf(&from->ms, from->addr, he->level, bf, size, width);
+ return _hist_entry__sym_snprintf(&from->ms, from->al_addr,
+ he->level, bf, size, width);
}

return repsep_snprintf(bf, size, "%-*.*s", width, width, "N/A");
@@ -881,7 +882,8 @@ static int hist_entry__sym_to_snprintf(struct hist_entry *he, char *bf,
if (he->branch_info) {
struct addr_map_symbol *to = &he->branch_info->to;

- return _hist_entry__sym_snprintf(&to->ms, to->addr, he->level, bf, size, width);
+ return _hist_entry__sym_snprintf(&to->ms, to->al_addr,
+ he->level, bf, size, width);
}

return repsep_snprintf(bf, size, "%-*.*s", width, width, "N/A");
--
2.17.1
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