Re: [RFC PATCH 0/6] Convert all tasklets to workqueues

From: david
Date: Fri Jun 22 2007 - 18:11:33 EST


On Fri, 22 Jun 2007, Daniel Walker wrote:


On Fri, 2007-06-22 at 22:40 +0200, Ingo Molnar 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)? It seems like Christoph's suggestion of converting
all the tasklets individually might be a better option, to deal with
specific pitfalls.

that would be the safe way to do it, but it will take a lot of time and a lot of testing.

it's probably better to try the big-bang change and only if you see problames go back and break things down.

remember, these changes have been in use in -rt for a while. there's reason to believe that they aren't going to cause drastic problems.

David Lang
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