From: Benjamin Moody <benjamin.moody@gmail.com>
To: Vince Weaver <vincent.weaver@maine.edu>
Cc: David Ahern <dsahern@gmail.com>, linux-perf-users@vger.kernel.org
Subject: Re: Bizarre results from perf event API
Date: Sun, 22 Feb 2015 20:12:26 +0000 [thread overview]
Message-ID: <CAAk6P0V0QyCtBTi+zULhK_wwSQLN3xsLZq0uXWaBFkjar3BmWQ@mail.gmail.com> (raw)
In-Reply-To: <alpine.DEB.2.11.1502211758120.24085@vincent-weaver-1.umelst.maine.edu>
On 2/21/15, Vince Weaver <vincent.weaver@maine.edu> wrote:
> On Sat, 21 Feb 2015, Benjamin Moody wrote:
>
>
>> there are grandchild processes involved. (And I can't help thinking
>> the first version is a lot more elegant!) Does the kernel somehow get
>> confused because enable_on_exec is set and the original process hasn't
>> actually exec'ed anything?
>
> Have you tried enabling the "inherit_stat" flag to see if that helps?
That does seem to help for the simple case I posted. It doesn't work
in all cases, though. I'll have to experiment a bit to find a simple
example.
My impression was that the inherit_stat bit shouldn't matter if we are
only interested in aggregate event counts, as opposed to counting
events per thread (found a ML thread about this a while ago but I
can't find it right now.) Please correct me if I'm wrong. In any
case, though, the perf tool doesn't use that bit.
Benjamin
next prev parent reply other threads:[~2015-02-22 20:12 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-02-20 23:26 Bizarre results from perf event API Benjamin Moody
2015-02-21 0:39 ` David Ahern
2015-02-21 21:44 ` Benjamin Moody
2015-02-21 22:59 ` Vince Weaver
2015-02-22 20:12 ` Benjamin Moody [this message]
2015-02-22 20:37 ` Vince Weaver
2015-02-24 0:46 ` Benjamin Moody
2015-02-24 1:21 ` David Ahern
2015-02-27 21:41 ` Benjamin Moody
2015-02-23 20:44 ` Andi Kleen
2015-02-23 23:13 ` Benjamin Moody
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=CAAk6P0V0QyCtBTi+zULhK_wwSQLN3xsLZq0uXWaBFkjar3BmWQ@mail.gmail.com \
--to=benjamin.moody@gmail.com \
--cc=dsahern@gmail.com \
--cc=linux-perf-users@vger.kernel.org \
--cc=vincent.weaver@maine.edu \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).