From: Thomas Gleixner <tglx@linutronix.de>
To: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Cc: John Stultz <john.stultz@linaro.org>,
Stephen Boyd <sboyd@codeaurora.org>,
Chris Wilson <chris@chris-wilson.co.uk>,
linux-kernel@vger.kernel.org
Subject: Re: Creating cyclecounter and lock member in timecounter structure [ Was Re: [RFC 1/4] drm/i915/perf: Add support to correlate GPU timestamp with system time]
Date: Thu, 23 Nov 2017 19:59:40 +0100 (CET) [thread overview]
Message-ID: <alpine.DEB.2.20.1711231947280.2364@nanos> (raw)
In-Reply-To: <d529503f-2eb3-b353-763d-901235383c6c@intel.com>
On Thu, 23 Nov 2017, Sagar Arun Kamble wrote:
> We needed inputs on possible optimization that can be done to
> timecounter/cyclecounter structures/usage.
> This mail is in response to review of patch
> https://patchwork.freedesktop.org/patch/188448/.
>
> As Chris's observation below, about dozen of timecounter users in the kernel
> have below structures
> defined individually:
>
> spinlock_t lock;
> struct cyclecounter cc;
> struct timecounter tc;
>
> Can we move lock and cc to tc? That way it will be convenient.
> Also it will allow unifying the locking/overflow watchdog handling across all
> drivers.
Looks like none of the timecounter usage sites has a real need to separate
timecounter and cyclecounter.
The lock is a different question. The locking of the various drivers
differs and I have no idea how you want to handle that. Just sticking the
lock into the datastructure and then not making use of it in the
timercounter code and leave it to the callsites does not make sense.
Thanks,
tglx
next prev parent reply other threads:[~2017-11-23 18:59 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1510748034-14034-1-git-send-email-sagar.a.kamble@intel.com>
[not found] ` <1510748034-14034-2-git-send-email-sagar.a.kamble@intel.com>
[not found] ` <151074872901.26264.3145709294590477412@mail.alporthouse.com>
2017-11-23 7:34 ` Creating cyclecounter and lock member in timecounter structure [ Was Re: [RFC 1/4] drm/i915/perf: Add support to correlate GPU timestamp with system time] Sagar Arun Kamble
2017-11-23 18:59 ` Thomas Gleixner [this message]
2017-11-24 9:06 ` Sagar Arun Kamble
2017-11-24 13:31 ` Thomas Gleixner
2017-11-27 10:05 ` Sagar Arun Kamble
2017-11-30 21:03 ` Saeed Mahameed
2017-12-01 7:42 ` Sagar Arun Kamble
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=alpine.DEB.2.20.1711231947280.2364@nanos \
--to=tglx@linutronix.de \
--cc=chris@chris-wilson.co.uk \
--cc=john.stultz@linaro.org \
--cc=linux-kernel@vger.kernel.org \
--cc=sagar.a.kamble@intel.com \
--cc=sboyd@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).