Re: [QUESTION] perf annotate: how do we fix the 'total period' feature ?

From: Taeung Song
Date: Wed Jul 05 2017 - 02:50:55 EST

Hi Namhyung :)

On 07/05/2017 03:07 PM, Namhyung Kim wrote:
Hi Taeung,

On Wed, Jul 5, 2017 at 2:47 PM, Taeung Song <treeze.taeung@xxxxxxxxx> wrote:

Two problems of perf-annotate were mentioned in recent PATCH reviews
by Milian and Namhyung.

Currently perf-annotate has a '--show-total-period' option
and a 't' key "Toggle total period view" on TUI browser.

Hmm... I didn't notice it has the option. I think its name is
incorrect and should be --show-nr-samples in accordance with perf

Okey, I got it.

However, they actually show the number of samples, not period(Raw number of
event count of sample).
So it's a different number to the perf report like below.

For example,

$ perf report --stdio --show-nr-sample --show-total-period -S hex2u64
# Overhead Samples Period Command Shared Object
# ........ ............ ............ ....... .............
3.07% 36 26484668 perf perf

$ perf annotate --stdio --show-total-period -s hex2u64
Percent | Source code & Disassembly of perf for cycles:ppp (36
: Disassembly of section .text:
: 000000000053ef9e <hex2u64>:
: hex2u64():
0 : 53ef9e: push %rbp
0 : 53ef9f: mov %rsp,%rbp
0 : 53efa2: sub $0x30,%rsp
1 : 53efa6: callq 424810
0 : 53efab: mov %rdi,-0x28(%rbp)
2 : 53efaf: mov %rsi,-0x30(%rbp)

1) the total period of perf-annotate is different from perf-report's
2) perf-annotate only shows the first column as 'Percent'
(even though the number of samples for each addr are actually printed)

So we need to just rename it ? ('total period' -> 'samples')

we should enable perf-annotate to support both features for 'periods' and
'samples' ?

I think we should support both. Then you need to change the code to
save periods when processing samples and show them in the annotate


Currently perf-annotate only count the number of samples for each addr
in __symbol__inc_addr_samples() of util/annotate.c when processing samples.
But it seems to make new functions for 'periods'..

Okey, I got hints of how to fix this problems.
will send the PATCH for them ! :)