From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx200.postini.com [74.125.245.200]) by kanga.kvack.org (Postfix) with SMTP id BDAB36B0032 for ; Thu, 16 May 2013 07:52:22 -0400 (EDT) Date: Thu, 16 May 2013 21:52:12 +1000 From: Dave Chinner Subject: Re: [PATCH] mm: vmscan: handle any negative return value from scan_objects Message-ID: <20130516115212.GC11167@devil.localdomain> References: <1368693736-15486-1-git-send-email-oskar.andero@sonymobile.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1368693736-15486-1-git-send-email-oskar.andero@sonymobile.com> Sender: owner-linux-mm@kvack.org List-ID: To: Oskar Andero Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Radovan Lekanovic , David Rientjes , Glauber Costa , Andrew Morton , Hugh Dickins , Greg Kroah-Hartman On Thu, May 16, 2013 at 10:42:16AM +0200, Oskar Andero wrote: > The shrinkers must return -1 to indicate that it is busy. Instead, treat > any negative value as busy. Why? The API defines return condition for aborting a scan and gives a specific value for doing that. i.e. explain why should change the API to over-specify the 'abort scan" return value like this. FWIW, using "any" negative number for "abort scan" is a bad API design decision. It means that in future we can't introduce different negative return values in the API if we have a new to. i.e. each specific negative return value needs to have the potential for defining a different behaviour. So if any change needs to be made, it is to change the -1 return value to an enum and have the shrinkers return that enum when they want an abort. -Dave. -- Dave Chinner dchinner@redhat.com -- 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