All of lore.kernel.org
 help / color / mirror / Atom feed
From: Cyrill Gorcunov <gorcunov@gmail.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: Rakib Mullick <rakib.mullick@gmail.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	"H. Peter Anvin" <hpa@zytor.com>,
	LKML <linux-kernel@vger.kernel.org>,
	x86@kernel.org
Subject: Re: [PATCH] x86, apic: Do not increment disabled_cpus from generic_processor_info.
Date: Sun, 09 Jan 2011 14:44:12 +0300	[thread overview]
Message-ID: <4D299F8C.9070700@gmail.com> (raw)
In-Reply-To: <20110109093926.GB542@elte.hu>

On 01/09/2011 12:39 PM, Ingo Molnar wrote:
> 
> * Rakib Mullick <rakib.mullick@gmail.com> wrote:
> 
>>  disabled_cpus has been incremented from the call path of
>> generic_processor_info (i.e from  acpi_register_lapic and
>> MP_processor_info) when a perticular cpu is not enabled. So, we can
>> remove the redundant increment of disabled_cpus from
>> generic_processor_info.
>>
>>
>> Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
...
> Hm, what effects does this have in practice? smpboot.c uses disabled_cpus as a value 
> to calculate limits - why has this bug not caused some misbehavior somewhere? (or if 
> it has caused misbehavior, what is that?)
>  
> Thanks,
> 
> 	Ingo

This disabled cpu may happen if nr_cpus early param specified and it's less than
nr_cpu_ids, but cpu might still be enabled in mp/acpi so we have to disable it.
And if we will not increment disabled_cpus this will lead the further report
about disabled cpu would refer to wrong cpu number. So I don't see why we
need to remove this disabled_cpus increment here.

Rakib is there something I miss?

-- 
    Cyrill

  reply	other threads:[~2011-01-09 11:44 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-01-09  6:29 [PATCH] x86, apic: Do not increment disabled_cpus from generic_processor_info Rakib Mullick
2011-01-09  9:39 ` Ingo Molnar
2011-01-09 11:44   ` Cyrill Gorcunov [this message]
2011-01-09 17:09     ` Rakib Mullick
2011-01-09 16:57   ` Rakib Mullick
2011-01-09 18:38     ` Cyrill Gorcunov
2011-01-10  4:06       ` Rakib Mullick
2011-01-10  9:57         ` Cyrill Gorcunov
2011-01-10 14:04           ` Rakib Mullick

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=4D299F8C.9070700@gmail.com \
    --to=gorcunov@gmail.com \
    --cc=hpa@zytor.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=rakib.mullick@gmail.com \
    --cc=tglx@linutronix.de \
    --cc=x86@kernel.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 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.