Re: DRM lock ordering fix series

[Andi Kleen]

Eric Anholt <eric@xxxxxxxxxx> writes:

> Here's hopefully the final attempt at the lock ordering fix for GEM.  The
> problem was introduced in .29 with the GTT mapping support.  We hashed out
> a few potential fixes on the mailing list and at OSTS.  Peter's plan was
> to use get_user_pages, but it has significant CPU overhead (10% cost to text
> rendering, though part of that is due to some dumb userland code.  But it's
> dumb userland code we're all running).


You are aware that there is a fast path now (get_user_pages_fast) which
is significantly faster? (but has some limitations)

-Andi

-- 
ak@xxxxxxxxxxxxxxx -- Speaking for myself only.
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