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Date:   Mon, 18 Oct 2010 14:46:02 +0400
From:   "Gleb O. Raiko" <raiko@niisi.msk.ru>
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To:     Ralf Baechle <ralf@linux-mips.org>
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Subject: Re: Question about Context register in TLB refilling
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On 18.10.2010 4:00, Ralf Baechle wrote:
> The aliasing problem is solvable and it may be worth to revisit that old
> piece of code again now 15 years later.

Before anybody will start to prepare patches, I'd like to note using 
c0_context allows less than 128 processes (their mm contexts in fact but 
who cares) to be directly mapped on 32-bit cpus. So, some kind of 
caching needs to be implemented and it will add overhead on every mm 
switch. Sure, this overhead might be bounded for a real case where there 
is a small number of processes, so they all fit in the cache.
--- Beware, wild assumptions here ---
I'm afraid the cost of such caching still will be higher than loading 
pgd_current even from main memory on tlb refill.
--- End of wild assumptions ---

Gleb.