All of lore.kernel.org
 help / color / mirror / Atom feed
From: Preeti U Murthy <preeti@linux.vnet.ibm.com>
To: Ingo Molnar <mingo@kernel.org>, Peter Zijlstra <peterz@infradead.org>
Cc: nicolas.pitre@linaro.org, rjw@rjwysocki.net,
	linux-kernel@vger.kernel.org, tglx@linutronix.de,
	linuxppc-dev@lists.ozlabs.org
Subject: Re: [PATCH V2] clockevents: Fix cpu down race for hrtimer based broadcasting
Date: Thu, 02 Apr 2015 18:14:18 +0530	[thread overview]
Message-ID: <551D39A2.8020009@linux.vnet.ibm.com> (raw)
In-Reply-To: <20150402121247.GA18104@gmail.com>

On 04/02/2015 05:42 PM, Ingo Molnar wrote:
> 
> * Peter Zijlstra <peterz@infradead.org> wrote:
> 
>> On Thu, Apr 02, 2015 at 12:42:27PM +0200, Ingo Molnar wrote:
>>> So why not use a suitable CPU_DOWN* notifier for this, instead of open 
>>> coding it all into a random place in the hotplug machinery?
>>
>> Because notifiers are crap? ;-) [...]
> 
> No doubt - but I didn't feel this poorly named random call into the 
> hotplug code, with no comments was any better.
> 
>> [...] Its entirely impossible to figure out what's happening to core 
>> code in hotplug. You need to go chase down and random order notifier 
>> things.
>>
>> I'm planning on taking out many of the core hotplug notifiers and 
>> hard coding their callbacks into the hotplug code.
> 
> That's very welcome news - but please also lets put in place a proper 
> namespace for all these callbacks, to make them easy to find and 
> change: hotplug_cpu__*() or so, which in this case would turn into 
> hotplug_cpu__tick_pull() or so?
> 
>> That way at least its clear wtf happens when.
> 
> Okay. I'll resurrect the fix with a hotplug_cpu__tick_pull() name - 
> agreed?

Sounds good to me. This needs to be marked to stable also.

Regards
Preeti U Murthy


WARNING: multiple messages have this Message-ID (diff)
From: Preeti U Murthy <preeti@linux.vnet.ibm.com>
To: Ingo Molnar <mingo@kernel.org>, Peter Zijlstra <peterz@infradead.org>
Cc: nicolas.pitre@linaro.org, linuxppc-dev@lists.ozlabs.org,
	tglx@linutronix.de, rjw@rjwysocki.net,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH V2] clockevents: Fix cpu down race for hrtimer based broadcasting
Date: Thu, 02 Apr 2015 18:14:18 +0530	[thread overview]
Message-ID: <551D39A2.8020009@linux.vnet.ibm.com> (raw)
In-Reply-To: <20150402121247.GA18104@gmail.com>

On 04/02/2015 05:42 PM, Ingo Molnar wrote:
> 
> * Peter Zijlstra <peterz@infradead.org> wrote:
> 
>> On Thu, Apr 02, 2015 at 12:42:27PM +0200, Ingo Molnar wrote:
>>> So why not use a suitable CPU_DOWN* notifier for this, instead of open 
>>> coding it all into a random place in the hotplug machinery?
>>
>> Because notifiers are crap? ;-) [...]
> 
> No doubt - but I didn't feel this poorly named random call into the 
> hotplug code, with no comments was any better.
> 
>> [...] Its entirely impossible to figure out what's happening to core 
>> code in hotplug. You need to go chase down and random order notifier 
>> things.
>>
>> I'm planning on taking out many of the core hotplug notifiers and 
>> hard coding their callbacks into the hotplug code.
> 
> That's very welcome news - but please also lets put in place a proper 
> namespace for all these callbacks, to make them easy to find and 
> change: hotplug_cpu__*() or so, which in this case would turn into 
> hotplug_cpu__tick_pull() or so?
> 
>> That way at least its clear wtf happens when.
> 
> Okay. I'll resurrect the fix with a hotplug_cpu__tick_pull() name - 
> agreed?

Sounds good to me. This needs to be marked to stable also.

Regards
Preeti U Murthy

  reply	other threads:[~2015-04-02 12:44 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-03-30  9:29 [PATCH V2] clockevents: Fix cpu down race for hrtimer based broadcasting Preeti U Murthy
2015-03-31  3:11 ` Nicolas Pitre
2015-03-31  3:11   ` Nicolas Pitre
2015-04-02 10:42 ` Ingo Molnar
2015-04-02 10:42   ` Ingo Molnar
2015-04-02 11:25   ` Preeti U Murthy
2015-04-02 11:25     ` Preeti U Murthy
2015-04-02 11:31     ` Ingo Molnar
2015-04-02 11:31       ` Ingo Molnar
2015-04-02 11:44       ` Preeti U Murthy
2015-04-02 12:02   ` Peter Zijlstra
2015-04-02 12:02     ` Peter Zijlstra
2015-04-02 12:12     ` Ingo Molnar
2015-04-02 12:12       ` Ingo Molnar
2015-04-02 12:44       ` Preeti U Murthy [this message]
2015-04-02 12:44         ` Preeti U Murthy
2015-04-02 12:58       ` Peter Zijlstra
2015-04-02 12:58         ` Peter Zijlstra
2015-04-02 14:30 ` [tip:timers/core] clockevents: Fix cpu_down() " tip-bot for Preeti U Murthy
2015-04-03 10:38   ` Preeti U Murthy
2015-04-03 10:50     ` Ingo Molnar
2015-04-06  4:28       ` Preeti U Murthy

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=551D39A2.8020009@linux.vnet.ibm.com \
    --to=preeti@linux.vnet.ibm.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=mingo@kernel.org \
    --cc=nicolas.pitre@linaro.org \
    --cc=peterz@infradead.org \
    --cc=rjw@rjwysocki.net \
    --cc=tglx@linutronix.de \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.