From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 29 Apr 2008 23:05:43 -0700 (PDT) Message-Id: <20080429.230543.98200575.davem@davemloft.net> Subject: Re: [rfc] data race in page table setup/walking? From: David Miller In-Reply-To: <20080430060340.GE27652@wotan.suse.de> References: <20080429050054.GC21795@wotan.suse.de> <20080430060340.GE27652@wotan.suse.de> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org From: Nick Piggin Date: Wed, 30 Apr 2008 08:03:40 +0200 Return-Path: To: npiggin@suse.de Cc: hugh@veritas.com, torvalds@linux-foundation.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, benh@kernel.crashing.org List-ID: > Hardware walkers, I shouldn't worry too much about, except as a thought > exercise to realise that we have lockless readers. I think(?) alpha can > walk the linux ptes in hardware on TLB miss, but surely they will have > to do the requisite barriers in hardware too (otherwise things get > really messy) My understanding is that all Alpha implementations walk the page tables in PAL code. > Powerpc's find_linux_pte is one of the software walked lockless ones. > That's basically how I imagine hardware walkers essentially should operate. Sparc64 walks the page tables lockless in it's TLB hash table miss handling. MIPS does something similar. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org