Re: [Qemu-devel] [PATCHv11 00/31] aio / timers: Add AioContext timers and use ppoll

[Stefan Hajnoczi]

On Thu, Aug 15, 2013 at 09:34:08PM +0100, Alex Bligh wrote:
> [ This patch set is available from git at:
>    https://github.com/abligh/qemu/tree/aio-timers11
> As autogenerated patch 30 of the series is too large for the mailing list. ]
> 
> This patch series adds support for timers attached to an AioContext clock
> which get called within aio_poll.
> 
> In doing so it removes alarm timers and moves to use ppoll where possible.
> 
> This patch set 'sort of' passes make check (see below for caveat)
> including a new test harness for the aio timers, but has not been
> tested much beyond that. In particular, the win32 changes have not
> even been compile tested. Equally, alterations to use_icount
> are untested.
> 
> Caveat: I have had to alter tests/test-aio.c so the following error
> no longer occurs.
> 
> ERROR:tests/test-aio.c:346:test_wait_event_notifier_noflush: assertion 
> failed: (aio_poll(ctx, false))
> 
> As gar as I can tell, this check was incorrect, in that it checking
> aio_poll makes progress when in fact it should not make progress. I
> fixed an issue where aio_poll was (as far as I can tell) wrongly
> returning true on a timeout, and that generated this error.
> 
> Note also the comment on patch 19 in relation to a possible bug
> in cpus.c.
> 
> The penultimate patch is patch which is created in an automated manner
> using scripts/switch-timer-api, added in this patch set. It violates some
> coding standards (e.g. line length >= 80 characters), but this is preferable
> in terms of giving a provably correct conversion. This patch is too
> large for the mailing list, so
> 
> EITHER: get it from git at the URL at the top of this message.
> 
> OR: Do the following:
>  1. Apply patches 0000-0029 inclusive
>  2. Run scripts/switch-timer-api
>  3. git commit -a (+ suitable commit message)
>  4. Apply patch 0031
> 
> If there is demand I can split it one commit per file.
> 
> This patch set has been compile tested & make check tested on a
> 'christmas-tree' configuration, meaning a configuration with every --enable-*
> value tested that can be easily configured on Ubuntu Precise,
> after application of each patch.

Please run qemu-iotests on this series and fix any failures.  It is
failing with "I/O thread has spun for 1000 iterations".

Stefan