All of lore.kernel.org
 help / color / mirror / Atom feed
From: Linn Crosetto <linn@hp.com>
To: Yinghai Lu <yinghai@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>, "H. Peter Anvin" <hpa@zytor.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Prarit Bhargava <prarit@redhat.com>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v3] x86, irq: get correct available vectors for cpu disable
Date: Wed, 26 Mar 2014 12:55:35 -0600	[thread overview]
Message-ID: <20140326185535.GE24604@oranje.fc.hp.com> (raw)
In-Reply-To: <CAE9FiQUidLDFunEKpVPfSppO1qOzpVPMXW5utd939RdLLei_Fg@mail.gmail.com>

On Wed, Mar 26, 2014 at 10:04:52AM -0700, Yinghai Lu wrote:
> On Wed, Mar 26, 2014 at 9:50 AM, Linn Crosetto <linn@hp.com> wrote:
> > On Tue, Mar 25, 2014 at 05:18:53PM -0700, Yinghai Lu wrote:
> >
> > Just noting that not all bits above first_system_vector are set in the bitmap,
> > so the comment in asm/desc.h and the change log could be misleading:
> >
> > /* used_vectors is BITMAP for irq is not managed by percpu vector_irq */
> >
> 
> Do you mean some vector that is neither used by percpu_vector_irq nor
> system_vector
> after first_system_vector ?

Yes, that is the case. In my previous example, first_system_vector is 239, but
test_bit(240, used_vectors) would return unset, though it cannot be used by
percpu vector_irq. If it marked all vectors unusable by percpu vector_irq, then
all bits above first_system_vector would be set.

> Anyway if bit is set in used_vectors, that vector can not be used by
> percpu vector_irq.
> 
> so that statement looks still right.
> 
> Feel free to suggest right comment or changelog.

The following might be more accurate:

/* 
 * The used_vectors BITMAP marks IRQs not managed by percpu vector_irq, below
 * first_system_vector. Vectors above first_system_vector are not managed by
 * percpu vector_irq.
 */

      reply	other threads:[~2014-03-26 18:55 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-01-28 21:54 [PATCH v3] x86, irq: get correct available vectors for cpu disable Yinghai Lu
2014-01-31 13:14 ` Prarit Bhargava
2014-02-06 19:12 ` Prarit Bhargava
2014-03-25 20:03 ` Linn Crosetto
2014-03-26  0:18   ` Yinghai Lu
2014-03-26 16:50     ` Linn Crosetto
2014-03-26 17:04       ` Yinghai Lu
2014-03-26 18:55         ` Linn Crosetto [this message]

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=20140326185535.GE24604@oranje.fc.hp.com \
    --to=linn@hp.com \
    --cc=hpa@zytor.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=prarit@redhat.com \
    --cc=tglx@linutronix.de \
    --cc=yinghai@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.