LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Christoph Hellwig <hch@infradead.org>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Sumant Patro <sumantp@lsil.com>,
	James.Bottomley@SteelEye.com, linux-scsi@vger.kernel.org,
	linux-kernel@vger.kernel.org, neela.kolli@lsi.com,
	bo.yang@lsi.com, sumant.patro@lsi.com
Subject: Re: [PATCH 4/5] scsi: megaraid_sas - preallocate memory for ioctl processing
Date: Thu, 8 Feb 2007 19:38:27 +0000	[thread overview]
Message-ID: <20070208193827.GA2354@infradead.org> (raw)
In-Reply-To: <20070207133020.4c58e271.akpm@linux-foundation.org>

On Wed, Feb 07, 2007 at 01:30:20PM -0800, Andrew Morton wrote:
> On Tue, 06 Feb 2007 14:19:54 -0800
> Sumant Patro <sumantp@lsil.com> wrote:
> 
> > Preallocate memory for ioctl processing. This is to avoid situations 
> > where ioctl fails for lack of memory (when system under heavy stress).
> > The memory pool will have 8*4K, 4*8K and 1*64K memory chunks
> 
> mutter.
> 
> I suspect all this horror is due to stupidity in the DMA API.
> 
> pci_alloc_consistent() just goes and assumes GFP_ATOMIC, whereas
> the caller (megasas_mgmt_fw_ioctl) would have been perfectly happy
> to use GFP_KERNEL.
> 
> I bet this fixes it:

but it's ugly as hell, why there is a much more trivial fix for it:
simply use dma_alloc_coherent.


      parent reply	other threads:[~2007-02-08 19:38 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-02-06 22:19 Sumant Patro
2007-02-07 21:30 ` Andrew Morton
2007-02-07 22:02   ` James Bottomley
2008-10-16  0:17     ` CaT
2008-10-16 13:54       ` Yang, Bo
2008-10-16 21:51         ` CaT
2007-02-08 19:38   ` Christoph Hellwig [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=20070208193827.GA2354@infradead.org \
    --to=hch@infradead.org \
    --cc=James.Bottomley@SteelEye.com \
    --cc=akpm@linux-foundation.org \
    --cc=bo.yang@lsi.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-scsi@vger.kernel.org \
    --cc=neela.kolli@lsi.com \
    --cc=sumant.patro@lsi.com \
    --cc=sumantp@lsil.com \
    --subject='Re: [PATCH 4/5] scsi: megaraid_sas - preallocate memory for ioctl processing' \
    /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

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).