Re: [RFC] sched: implement the exclusive wait queue as a LIFO queue

[David Howells]

Changli Gao <xiaosuo@xxxxxxxxx> wrote:

> If there isn't enough work to be done, we'd better not disrupt them
> and  leave them sleeping forever to keep the scheduler happier. Do we
> have reason to keep fair to all the workers? Does it have benefit?

You've made one important assumption: the processes on the wait queue are
sleeping waiting to service things... but what if the wait queue governs
access to a resource, and all the processes on that wait queue need access to
that resource to do things?  Some of the processes waiting for it may never
get a go, and so necessary work may be left undone.

So NACK.

David
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