lkml.org 
[lkml]   [2007]   [Mar]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [patch 13/13] signalfd/timerfd/asyncfd v5 - KAIO asyncfd support (example/maybe-broken) ...
On Wed, 14 Mar 2007, Linus Torvalds wrote:

> On Wed, 14 Mar 2007, Davide Libenzi wrote:
> > >
> > > That won't work. aio_complete() is supposed to be irq safe.
> >
> > Can you point me to a kernel path that ends up calling aio_complete() in a
> > do-not-sleep mode?
>
> All of them.
>
> It's called from dio_bio_end_aio(), which is the bi_end_io function for an
> AIO action. Which in turn is called at IO completion time.
>
> Which is basically _always_ interrupt context.
>
> So you cannot sleep. It's not about holding spinlocks (which it might well
> do as well). It's about a much more fundamental issue: you can only sleep
> in process context, not from interrupts.

Ack! Gotcha. Sigh! :)



- Davide


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2007-03-15 01:23    [W:0.051 / U:0.480 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site