lkml.org 
[lkml]   [2004]   [Dec]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] pcxx: replace cli()/sti() with spin_lock_irqsave()/spin_unlock_irqrestore()
Alan Cox wrote:
> On Llu, 2004-12-20 at 14:59, Alan Cox wrote:
>
>>On Gwe, 2004-12-17 at 22:34, James Nelson wrote:
>>
>>>- save_flags(flags);
>>>- cli();
>>>+ spin_lock_irqsave(&pcxx_lock, flags);
>>> del_timer_sync(&pcxx_timer);
>>
>>Not safe if the lock is grabbed by the timer between the lock and the
>>irqsave as it will spin on another cpu and the timer delete will never
>>finish.
>
>
> Error between brain and keyboard
>
> Between the lock and the timer_delete of course
>

Right.

Go ahead and ignore that set of cli()/sti() patches - I'll have to take them a
little slower, checking for potential deadlocks and other nastiness.

I'll try again in a week or so - gotta finish "The Design of the Unix Operating
System" first. Love early Xmas presents from my aunt, the mainframe systems
programmer... :)
-
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: 2005-03-22 14:08    [W:0.488 / U:0.008 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site