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Date: Sat, 28 Apr 2007 13:04:40 +1000
From: Nick Piggin <nickpiggin@yahoo.com.au>
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To: Nick Piggin <nickpiggin@yahoo.com.au>
CC: rohitseth@google.com, Mike Stroyan <mike.stroyan@hp.com>,
       Andrew Morton <akpm@linux-foundation.org>,
       Hugh Dickins <hugh@veritas.com>, "Luck, Tony" <tony.luck@intel.com>,
       linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: Fw: [PATCH] ia64: race flushing icache in do_no_page path
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Nick Piggin wrote:

> What if you were to say remove all the PG_arch_1 code, and do something
> really simple like flush icache in flush_dcache_page? Would performance
> suffer horribly?

OIC, you need a virtual address to evict the icache, so you can't
flush at flush_dcache time? Or does ia64 have an instruction to
flush the whole icache? (it would be worth testing, to see how much
performance suffers).

-- 
SUSE Labs, Novell Inc.