From: Jiri Olsa <jolsa@redhat.com>
To: Raghavendra Rao Ananta <rananta@codeaurora.org>
Cc: peterz@infradead.org, mingo@redhat.com, acme@kernel.org,
alexander.shishkin@linux.intel.com, namhyung@kernel.org,
linux-kernel@vger.kernel.org, psodagud@codeaurora.org,
tsoni@codeaurora.org
Subject: Re: [PATCH] perf: Add support for creating offline events
Date: Mon, 12 Feb 2018 22:04:42 +0100 [thread overview]
Message-ID: <20180212210442.GA32093@krava> (raw)
In-Reply-To: <53408020-8638-4947-90f6-87dbc4c2c4e5@codeaurora.org>
On Mon, Feb 12, 2018 at 09:42:05AM -0800, Raghavendra Rao Ananta wrote:
> Hi Jiri,
>
> Thank you for the response.
>
> Does perf tool has its own check to see if the CPU was offline during the
> lifetime of an event? If so, it might ignore these type of events.
nope, we don't check on that
>
> Initially, I tested the same using perf tool and found similar results.
> Then I debugged further and found that the perf core was actually sending
> data to the userspace (copy_to_user()) and the corresponding count for the
> data. Hence, I tested this further by writing my own userspace application,
> and I was able to read the count through this,
> even when the CPU was made offline and back online.
>
> Do you think we also have to modify the perf tool accordingly?
hum, I wonder what's wrong.. will check
jirka
next prev parent reply other threads:[~2018-02-12 21:04 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-02-09 23:07 [PATCH] perf: Add support for creating offline events Raghavendra Rao Ananta
2018-02-12 9:43 ` Jiri Olsa
2018-02-12 17:42 ` Raghavendra Rao Ananta
2018-02-12 21:04 ` Jiri Olsa [this message]
2018-02-12 21:21 ` Jiri Olsa
2018-02-12 22:22 ` Raghavendra Rao Ananta
2018-02-13 16:08 ` Jiri Olsa
2018-02-13 18:03 ` Raghavendra Rao Ananta
2018-02-12 9:44 ` Jiri Olsa
2018-02-12 19:11 ` kbuild test robot
2018-02-13 18:23 ` Peter Zijlstra
2018-02-13 22:17 ` Sodagudi Prasad
2018-02-14 8:32 ` Peter Zijlstra
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=20180212210442.GA32093@krava \
--to=jolsa@redhat.com \
--cc=acme@kernel.org \
--cc=alexander.shishkin@linux.intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=namhyung@kernel.org \
--cc=peterz@infradead.org \
--cc=psodagud@codeaurora.org \
--cc=rananta@codeaurora.org \
--cc=tsoni@codeaurora.org \
/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).