On Thu, Sep 12, 2002 at 09:23:15AM +0200, Benjamin Herrenschmidt wrote:

quoted

quoted

That's the least of our worries - the current consistent_alloc() is
badly broken.  It breaks the DMA-mapping.txt rules, because it can't
safely be called from interrupt context.  I think we need generic
changes (gfp masks to various functions) to fix this sanely.

IIRC, to fix the interrupt context bit, we need something like the
following, which was Paul's idea, and he said he would talk to Dave M.
about it.  Did anything ever happen there?

I tend to hate anything that relies on in_interrupt() as they
are other contexts that will have in_interrupt() cleared but still
have the same limitations. Typically, anything on the VM path must
do either GFP_ATOMIC or GFP_NOIO allocations, wether it's running
at interrupt time or not.

The problem is that the atomic pool is limited, iirc.

--
Tom Rini (TR1265)
http://gate.crashing.org/~trini/

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