qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Stefan Hajnoczi <stefanha@gmail.com>
To: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>,
	mjt@tls.msk.ru, qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] [PATCH] iov: avoid memcpy for "simple" iov_from_buf/iov_to_buf
Date: Tue, 22 Dec 2015 16:34:10 +0800	[thread overview]
Message-ID: <20151222083410.GA30435@stefanha-x1.localdomain> (raw)
In-Reply-To: <20151218050843.GA13945@stefanha-x1.localdomain>

[-- Attachment #1: Type: text/plain, Size: 916 bytes --]

On Fri, Dec 18, 2015 at 01:08:43PM +0800, Stefan Hajnoczi wrote:
> On Wed, Dec 16, 2015 at 11:57:33AM +0100, Paolo Bonzini wrote:
> > memcpy can take a large amount of time for small reads and writes.
> > For virtio it is a common case that the first iovec can satisfy the
> > whole read or write.  In that case, and if bytes is a constant to
> > avoid excessive growth of code, inline the first iteration
> > into the caller.
> > 
> > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> > ---
> >  include/qemu/iov.h | 32 ++++++++++++++++++++++++++++----
> >  util/iov.c         |  8 ++++----
> >  2 files changed, 32 insertions(+), 8 deletions(-)
> 
> Thanks, applied to my block-next tree:
> https://github.com/stefanha/qemu/commits/block-next

Paolo, I've dropped this from block-next because it breaks
tests/test-iov.

Please resolve the failure and submit a new patch.

Thanks,
Stefan

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 473 bytes --]

      reply	other threads:[~2015-12-22  8:34 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-12-16 10:57 [Qemu-devel] [PATCH] iov: avoid memcpy for "simple" iov_from_buf/iov_to_buf Paolo Bonzini
2015-12-18  5:08 ` Stefan Hajnoczi
2015-12-22  8:34   ` Stefan Hajnoczi [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=20151222083410.GA30435@stefanha-x1.localdomain \
    --to=stefanha@gmail.com \
    --cc=mjt@tls.msk.ru \
    --cc=pbonzini@redhat.com \
    --cc=qemu-devel@nongnu.org \
    --cc=stefanha@redhat.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 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).