All of lore.kernel.org
 help / color / mirror / Atom feed
From: Paul Jackson <pj@sgi.com>
To: James Bottomley <James.Bottomley@SteelEye.com>
Cc: lethal@linux-sh.org, linux-kernel@vger.kernel.org, akpm@osdl.org,
	spyro@f2s.com, tony@atomide.com, jamey.hicks@hp.com,
	joshua@joshuawise.com, david-b@pacbell.net, rmk@arm.linux.org.uk
Subject: Re: [PATCH] bitmap: Support for pages > BITS_PER_LONG.
Date: Fri, 20 Jan 2006 01:10:56 -0800	[thread overview]
Message-ID: <20060120011056.be8f23b2.pj@sgi.com> (raw)
In-Reply-To: <1137727710.3571.51.camel@mulgrave>

James wrote:
> Is wrong.  You're looking for an unset span of order bits at a given
> offset. 

But your comment, James, said:

 * This is used to allocate a memory region from a bitmap.  The idea is
 * that the region has to be 1<<order sized and 1<<order aligned (this
 * makes the search algorithm much faster).



So, like the other Paul said:
> Unless I'm missing something, I don't see how your case
> would happen.

James further wrote:
>   i.e. (assuming BITS_PER_LONG=32) for a span
> of 126 at offset 1, you check

I thought that the span had to be a power of two.  Perhaps
you mean 128, not 126 (order 7: 2**7 == 128).

And I thought, from your comment above, that if the span was
128, then the alignment had to be 128 as well.

-- 
                  I won't rest till it's the best ...
                  Programmer, Linux Scalability
                  Paul Jackson <pj@sgi.com> 1.925.600.0401

  parent reply	other threads:[~2006-01-20  9:11 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-01-19  1:48 [PATCH] bitmap: Support for pages > BITS_PER_LONG Paul Mundt
2006-01-19  3:11 ` Paul Jackson
2006-01-20  3:28   ` James Bottomley
2006-01-20  7:28     ` Paul Mundt
2006-01-20  9:10     ` Paul Jackson [this message]
2006-01-19  6:07 ` Paul Jackson
2006-01-19  6:40   ` Paul Jackson

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=20060120011056.be8f23b2.pj@sgi.com \
    --to=pj@sgi.com \
    --cc=James.Bottomley@SteelEye.com \
    --cc=akpm@osdl.org \
    --cc=david-b@pacbell.net \
    --cc=jamey.hicks@hp.com \
    --cc=joshua@joshuawise.com \
    --cc=lethal@linux-sh.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=rmk@arm.linux.org.uk \
    --cc=spyro@f2s.com \
    --cc=tony@atomide.com \
    /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.