From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from luxury.wat.veritas.com([10.10.192.121]) (1444 bytes) by megami.veritas.com via sendmail with P:esmtp/R:smart_host/T:smtp (sender: ) id for ; Wed, 4 Apr 2001 09:12:57 -0700 (PDT) (Smail-3.2.0.101 1997-Dec-17 #4 built 1999-Aug-24) Date: Wed, 4 Apr 2001 17:13:44 +0100 (BST) From: Hugh Dickins Subject: Re: pte_young/pte_mkold/pte_mkyoung In-Reply-To: <200104041600.RAA01119@raistlin.arm.linux.org.uk> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: rmk@arm.linux.org.uk Cc: linux-mm@kvack.org List-ID: On Wed, 4 Apr 2001 rmk@arm.linux.org.uk wrote: > > We currently seem to have: > 2 references to pte_mkyoung() > 1 reference to pte_mkold() > 0 references to pte_young() > > This tells me that we're no longer using the hardware page tables on x86 > for page aging, which leads me nicely on to the following question. > > Are there currently any plans to use the hardware page aging bits in the > future, and if there are, would architectures that don't have them be > required to have them? > > I'm asking this question because for some time (1.3 onwards), the ARM > architecture has had some code to handle software emulation of the young > and dirty bits. If its not required, then I'd like to get rid of this > software emulation. You may be out of luck: mm/vmscan.c try_to_swap_out() has if (ptep_test_and_clear_young(page_table)) { Hugh -- 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.eu.org/Linux-MM/