Re: [fix] Too async libata breakage

From: Arjan van de Ven
Date: Thu Jan 08 2009 - 17:29:43 EST


On Thu, 08 Jan 2009 14:20:38 -0800
"Justin P. Mattock" <justinmattock@xxxxxxxxx> wrote:

> Arjan van de Ven wrote:
> >>> Additional async_synchronize_full() helps and box boot to the end.
> >>>
> >
> > Hi Linus,
> >
> > can you add the patch below to your tree? This makes the
> > async_synchronize_full() a real absolute async barrier, rather than
> > just synchronizing the work scheduled upto the starting point.
> > It's a bit too much for some cases (so later on I might introduce
> > the softer synchronization again) but it solves some real problems
> > for people so this should go into -rc1 please...
> >
> > >From ca1827b142e41b54c612026b3c0b5d239f21a715 Mon Sep 17 00:00:00
> > >2001
> > From: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
> > Date: Thu, 8 Jan 2009 12:35:11 -0800
> > Subject: [PATCH] async: make async_synchronize_full() more
> > serializing
> >
> > turns out that there are real problems with allowing async
> > tasks that are scheduled from async tasks to run after
> > the async_synchronize_full() returns.
> >
> > This patch makes the _full more strict and a complete
> > synchronization. Later I might need to add back a lighter
> > form of synchronization for other uses.. but not right now.
> >
> > Signed-off-by: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
> > ---
> > kernel/async.c | 4 +++-
> > 1 files changed, 3 insertions(+), 1 deletions(-)
> >
> > diff --git a/kernel/async.c b/kernel/async.c
> > index 9737338..64cc916 100644
> > --- a/kernel/async.c
> > +++ b/kernel/async.c
> > @@ -206,7 +206,9 @@ EXPORT_SYMBOL_GPL(async_schedule_special);
> >
> > void async_synchronize_full(void)
> > {
> > - async_synchronize_cookie(next_cookie);
> > + do {
> > + async_synchronize_cookie(next_cookie);
> > + } while (!list_empty(&async_running)
> > || !list_empty(&async_pending)); }
> > EXPORT_SYMBOL_GPL(async_synchronize_full);
> >
> >
> I have to say that ohci/firescope is nice
> poof right up: dmesg shows up:
> attach is the results.
> unfortunantly nothing different than
> what the boot screen shows.

just to make clear: this is with the patch right?
because if not... try that..

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Arjan van de Ven Intel Open Source Technology Centre
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