[lkml]   [2007]   [Jun]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [RFC PATCH 0/6] Convert all tasklets to workqueues

* Daniel Walker <> wrote:

> > - tasklets have certain fairness limitations. (they are executed in
> > softirq context and thus preempt everything, even if there is
> > some potentially more important, high-priority task waiting to be
> > executed.)
> Since -rt has been executing tasklets in process context for a long
> time, I'm not sure this change would cause to many regressions.
> However, it seems like implicit dependencies on "tasklets preempt
> everything" might crop up. The other issue is if they don't "preempt
> everything" (most of the time), what default priority do we give them
> (all of the time)? [...]

there is no such guarantee at all (of 'instant preemption'), even with
current, softirq-based tasklets. A tasklet might be 'stolen' by another
CPU. It might be delayed to the next timer tick (or other softirq
execution). Or it might be delayed into a ksoftirqd context, which
currently runs at nice +19. So your worry of implicit execution
dependencies is unfounded, because, if they existed, they would be bad
(and triggerable) bugs today too.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2007-06-23 00:19    [W:0.161 / U:7.732 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site