Messages in this thread | | | Date | Wed, 14 Nov 2012 17:39:28 +0000 | From | Russell King - ARM Linux <> | Subject | Re: [RFC PATCH 0/3] introduce static_vm for ARM-specific static mapped area |
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On Thu, Nov 15, 2012 at 01:55:51AM +0900, Joonsoo Kim wrote: > In current implementation, we used ARM-specific flag, that is, > VM_ARM_STATIC_MAPPING, for distinguishing ARM specific static mapped area. > The purpose of static mapped area is to re-use static mapped area when > entire physical address range of the ioremap request can be covered > by this area. > > This implementation causes needless overhead for some cases.
In what cases?
> We unnecessarily iterate vmlist for finding matched area even if there > is no static mapped area. And if there are some static mapped areas, > iterating whole vmlist is not preferable.
Why not? Please put some explanation into your message rather than just statements making unexplained assertions.
> Another reason for doing this work is for removing architecture dependency > on vmalloc layer. I think that vmlist and vmlist_lock is internal data > structure for vmalloc layer. Some codes for debugging and stat inevitably > use vmlist and vmlist_lock. But it is preferable that they are used outside > of vmalloc.c as least as possible.
The vmalloc layer is also made available for ioremap use, and it is intended that architectures hook into this for ioremap support.
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