Re: kill task in TASK_UNINTERRUPTIBLE

[David Woodhouse <dwmw2@infradead.org>]

alan@lxorguk.ukuu.org.uk said:
>  Or waiting on a resource that isnt available - that can occur for
> example with NFS for long periods, or for a few minutes when burning a
> CD and the IDE bus is locked -

Often the main reason for sleeping in uninterruptible state during these 
periods is because the difficulty of performing a sane cleanup exceeds the 
boredom threshold of the programmer. There are plenty of places where 
TASK_UNINTERRUPTIBLE is used just because people have been lazy.

I'm guilty of it too - I use TASK_UNINTERRUPTIBLE for anything which can be
called from jffs2_read_inode() because I was too lazy to chase through a
mechanism by which ->read_inode() may return -ERESTARTSYS without creating a
permanent bad inode. But we're working on it, and this should get fixed in
2.5. 

--
dwmw2