[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Qemu-devel] [Qemu-block] [PATCH v2 09/13] block: Drain throttling q

From: Stefan Hajnoczi
Subject: Re: [Qemu-devel] [Qemu-block] [PATCH v2 09/13] block: Drain throttling queue with BdrvChild callback
Date: Mon, 9 May 2016 14:17:06 +0100
User-agent: Mutt/1.6.0 (2016-04-01)

On Fri, Apr 22, 2016 at 07:42:38PM +0200, Kevin Wolf wrote:
> This removes the last part of I/O throttling from block/io.c and moves
> it to the BlockBackend.
> Instead of having knowledge about throttling inside io.c, we can call a
> BdrvChild callback .drained_begin/end, which happens to drain the
> throttled requests for BlockBackend parents.
> Signed-off-by: Kevin Wolf <address@hidden>
> ---
>  block/block-backend.c     | 32 +++++++++++++++++++++++++++-----
>  block/io.c                | 39 ++++++++++++++++++---------------------
>  include/block/block_int.h |  8 +++-----
>  3 files changed, 48 insertions(+), 31 deletions(-)

I'm confused about the naming.  BdrvChildRole.drained_begin/end and
bdrv_parent_drained_begin/end have nothing to do with

If these were callbacks that happened at bdrv_drained_begin/end time
then I could understand, but that doesn't seem to be the case.

What are the semantics of these callbacks?  Maybe we can find a clearer
name.  I think the point is not to "drain" (in the sense of completing
requests) but simply to restart queued requests?

Attachment: signature.asc
Description: PGP signature

reply via email to

[Prev in Thread] Current Thread [Next in Thread]