Re: cmpxchg is not available to generic code

[David Miller]

From: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Date: Thu, 19 Jul 2007 00:05:49 -0700

> What's that code doing anyway?  driver-private locking primitives?

It's an atomic lock shared with userspace.  Whatever implementation is
used to do the lock on that object must be identical in the userspace
DRM bits.

Unlike futex, the lock operation on the user side isn't optional.
So if the platform can't do a true cmpxchg it generally cannot
support DRM.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/