Re: [PATCH 0/2] perf: add sort by inclusive time functionality (v2)

From: Arun Sharma
Date: Mon Mar 12 2012 - 14:21:07 EST


On 3/12/12 12:43 AM, Namhyung Kim wrote:

Known bugs:

total_period computation is broken for order=callee


I'd like to add two more :).

* If perf record misses callchain info, perf report will get stuck.
* If it's used with "symbol" sort order, it'll get stuck too.


Can you post the command lines you used to reproduce this? A backtrace on where perf report is getting stuck would be useful as well.

Since I didn't make any changes to the perf record or perf report code paths that don't involve "-s inclusive", I wonder if you see the same issues without my patch.

For missing callchain info cases, I'd expect cursor->nr to be zero. So loops such as:

+ for (i = 0; i < cursor->nr; i++) {

should terminate immediately.


BTW, I don't like the name 'inclusive' as a sort key. If it cares about
time, IMHO, the name should contain 'time' - something like 'itime' or
'inctime'?

The existing sort orders: pid, comm, dso, symbol, parent -- all care about time, but none of them have time in their name?


Furthermore, I don't think it is a sort key. As it doesn't sort
anything, and only affects the way calculating symbol's period value,
wouldn't it be better making it a separate switch rather than a sort
key? Plus, checking whether it has callchain data and symbol sort key
might be added also.

Yes, we're still sorting by period, but a redefined meaning of period (please see my other mail about period vs period_self). Previous iterations of this code did use a top level flag, but that namespace is getting a bit crowded.

-Arun
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