From mboxrd@z Thu Jan 1 00:00:00 1970 In-reply-to: <12004129652397-git-send-email-salikhmetov@gmail.com> (message from Anton Salikhmetov on Tue, 15 Jan 2008 19:02:43 +0300) Subject: Re: [PATCH 0/2] Updating ctime and mtime for memory-mapped files [try #4] References: <12004129652397-git-send-email-salikhmetov@gmail.com> Message-Id: From: Miklos Szeredi Date: Tue, 15 Jan 2008 21:27:09 +0100 Sender: owner-linux-mm@kvack.org Return-Path: To: salikhmetov@gmail.com Cc: linux-mm@kvack.org, jakob@unthought.net, linux-kernel@vger.kernel.org, valdis.kletnieks@vt.edu, riel@redhat.com, ksm@42.dk, staubach@redhat.com, jesper.juhl@gmail.com, torvalds@linux-foundation.org, a.p.zijlstra@chello.nl, akpm@linux-foundation.org, protasnb@gmail.com, miklos@szeredi.hu List-ID: > 1. Introduction > > This is the fourth version of my solution for the bug #2645: > > http://bugzilla.kernel.org/show_bug.cgi?id=2645 > > Changes since the previous version: > > 1) the case of retouching an already-dirty page pointed out > by Miklos Szeredi has been addressed; I'm a bit sceptical, as we've also pointed out, that this is not possible without messing with the page tables. Did you try my test program on the patched kernel? I've refreshed the patch, where we left this issue last time. It should basically have equivalent functionality to your patch, and is a lot simpler. There might be performance issues with it, but it's a good starting point. Miklos ---- Index: linux/mm/memory.c =================================================================== --- linux.orig/mm/memory.c 2008-01-09 21:16:30.000000000 +0100 +++ linux/mm/memory.c 2008-01-15 21:16:14.000000000 +0100 @@ -1680,6 +1680,8 @@ gotten: unlock: pte_unmap_unlock(page_table, ptl); if (dirty_page) { + if (vma->vm_file) + file_update_time(vma->vm_file); /* * Yes, Virginia, this is actually required to prevent a race * with clear_page_dirty_for_io() from clearing the page dirty @@ -2313,6 +2315,8 @@ out_unlocked: if (anon) page_cache_release(vmf.page); else if (dirty_page) { + if (vma->vm_file) + file_update_time(vma->vm_file); set_page_dirty_balance(dirty_page, page_mkwrite); put_page(dirty_page); } -- 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