Messages in this thread | | | Date | Tue, 17 Jun 2008 07:21:04 -0700 | From | Mike Travis <> | Subject | Re: [patch 04/41] cpu ops: Core piece for generic atomic per cpu operations |
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Rusty Russell wrote: > On Tuesday 17 June 2008 00:52:08 Christoph Lameter wrote: >> On Sun, 15 Jun 2008, Rusty Russell wrote: >>>> 3. Some hooks for arches to override particular behavior as needed. >>>> F.e. IA64 allocates percpu structures in a special way. x86_64 >>>> needs to do some tricks for the pda etc etc. >>> IA64 is going to need some work, since dynamic percpu addresses won't be >>> able to use their pinned TLB trick to get the local version. >> The ia64 hook could simply return the address of percpu area that >> was reserved when the per node memory layout was generated (which happens >> very early during node bootstrap). > > Apologies, this time I read the code. I thought IA64 used the pinned TLB area > to access per-cpu vars under some circumstances, but they only do that via an > arch-specific macro. > > So creating new congruent mappings to expand the percpu area(s) is our main > concern now? > > Rusty.
Not exactly. Getting the system to not panic early in the boot (before x86_64_start_kernel()) is the primary problem right now. This happens in the tip tree with the change to use zero-based percpu offsets. It gets much farther on the linux-next tree.
Thanks, Mike
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