Dynamic pcpu, arm, mips, powerpc, sun, etc. help needed

[Attilio Rao]

2009/6/21 Marius Strobl <marius at alchemy.franken.de>:
> On Wed, Jun 17, 2009 at 12:55:52PM -1000, Jeff Roberson wrote:
>>
>> On Tue, 9 Jun 2009, Peter Grehan wrote:
>>
>> >>As for sparc64 allocating the storage for the dynamic area
>> >>from end probably isn't a good idea as the pmap code assumes
>> >>that the range from KERNBASE to end is covered by the pages
>> >>allocated by and locked into the TLB for the kernel by the
>> >>loader
>> >
>> >Ditto for ppc. It's possible to get the additional space from within or
>> >after return from pmap_bootstrap() (like thread0's kstack, or the msgbuf).
>>
>> http://people.freebsd.org/~jeff/dpcpu.diff
>>
>> I have updated this patch based on feedback relating to various
>> architectures md code.  I tried to model most architectures after the way
>> msgbuf memory was taken.  I have no capacity to test anything other than
>> i386 and amd64.  ARM is reported to work with one minor diff.  Apparently
>> sparc64 worked with the earlier diff but this should be cleaner.  If
>> anyone can report back on sparc64, mips, or powerpc, I'd appreciate it.
>>
>
> The earlier patch worked on sparc64 as long as the kernel
> happened to leave enough room in the last 4MB page allocated
> for it.
> The new version unfortunately doesn't compile on sparc64 as
> pmap_bootstrap_alloc() is static to its pmap.c (I think it
> should also stay that way). Also the memory allocated with
> it isn't safe to be used before we've taken over the trap
> table. A kernel built with the sparc64 bits replaced with
> the following patch boots fine:
> http://people.freebsd.org/~marius/sparc64_dpcpu.diff
> Do you have some simple test case for DPCPU which can be
> used to verify that it actually works?

I can suggest to switch pc_rm_queue of rmlocks in pcpu to be used as dynamic.
It should not be difficult at all.

Thanks,
Attilio


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