From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Sun, 18 Apr 2004 08:52:19 -0700 From: William Lee Irwin III Subject: Re: PTE aging, ptep_test_and_clear_young() and TLB Message-ID: <20040418155219.GA743@holomorphy.com> References: <20040418093949.GY743@holomorphy.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org Return-Path: To: Hugh Dickins Cc: Russell King , linux-mm@kvack.org List-ID: On Sun, Apr 18, 2004 at 11:58:21AM +0100, Hugh Dickins wrote: > mm and address are directly available in both mine and Andrea's (the > difference between us is finding vma: mine needs find_vma in the anon > case, on Andrea's it's directly available), shouldn't be any need to > add in that ppc/ppc64 code. > Hmm, maybe I didn't look hard enough at it, and could have just taken > it out of ppc/ppc64, instead of moving it from generic; I'll go back > and check on that sometime. > I'm not surprised Russell's found he just needs mm rather than vma, > I did try briefly yesterday to understand just what it is that vma > gives to flush TLB. Needs thorough research through all the arches, > the ARM case is not necessarily representative. > Wouldn't surprise me if it turns out vma necessary on some in the > file-backed case, but on none in the anon case (would then cease > to be a differentiator between anonmm and anon_vma if so). I have to confess to not looking closely at the recent merge-oriented code. Passing the things in when they're available will do it. On Sun, Apr 18, 2004 at 11:58:21AM +0100, Hugh Dickins wrote: > But I still think that we'd want to cut down on the intercpu TLB > flushes for page_referenced, should batch them up to some extent. > Russell may well be right that we're much too lazy about the > referenced bit in 2.6, but that doesn't mean we now have to > jump and get it exactly right all the time: the dirty bit is > vital, the referenced bit never more than a hint. I'm not foreseeing many effective algorithms for batching TLB flushes there. Maybe something will get brewed up that surprises me. -- wli -- 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: aart@kvack.org