[Cbe-oss-dev] [RFC, PATCH 0/2] powerpc/spufs: allow access to scheduled-out NOSCHED contexts

[Kazunori Asayama]

Jeremy Kerr wrote:
> Currently, we have no way of accessing the "regs" file of SPE contexts
> created with the SPU_CREATE_NOSCHED flag. This means that libSPE can't
> set up the initial register set.
> 
> However, not all access to the register file of a NOSCHED context are
> invalid - the context may already be saved, or we may not currently
> be running the context (in which case, it'll be OK to save to the CSA).
> 
> The following patches allow access to the regs file (as well as other
> files previously restricted to schedulable contexts), by enabling us
> to call spu_acquire_saved on NOSCHED contexts. If a NOSCHED context
> would be descheduled due to this call, it will return with -EBUSY.

Even with these changes, regular SPE programs with NOSCHED don't work 
correctly because spu_create ignores the parameter 'npc' for all NOSCHED 
contexts and execution always starts at 0x0. Is it expected behavior? Or 
should be fixed?

-- 
(ASAYAMA Kazunori
   (asayama at sm.sony.co.jp))
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