From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: [patch 05/19] split LRU lists into anon & file sets From: Lee Schermerhorn In-Reply-To: <20080111143627.FD64.KOSAKI.MOTOHIRO@jp.fujitsu.com> References: <20080108205939.323955454@redhat.com> <20080108210002.638347207@redhat.com> <20080111143627.FD64.KOSAKI.MOTOHIRO@jp.fujitsu.com> Content-Type: text/plain Date: Fri, 11 Jan 2008 10:50:09 -0500 Message-Id: <1200066610.5304.11.camel@localhost> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: KOSAKI Motohiro Cc: Rik van Riel , linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On Fri, 2008-01-11 at 15:24 +0900, KOSAKI Motohiro wrote: > Hi Rik > > > +static inline int is_file_lru(enum lru_list l) > > +{ > > + BUILD_BUG_ON(LRU_INACTIVE_FILE != 2 || LRU_ACTIVE_FILE != 3); > > + return (l/2 == 1); > > +} > > below patch is a bit cleanup proposal. > i think LRU_FILE is more clarify than "/2". > > What do you think it? > > > > Index: linux-2.6.24-rc6-mm1-rvr/include/linux/mmzone.h > =================================================================== > --- linux-2.6.24-rc6-mm1-rvr.orig/include/linux/mmzone.h 2008-01-11 11:10:30.000000000 +0900 > +++ linux-2.6.24-rc6-mm1-rvr/include/linux/mmzone.h 2008-01-11 14:40:31.000000000 +0900 > @@ -147,7 +147,7 @@ > static inline int is_file_lru(enum lru_list l) > { > BUILD_BUG_ON(LRU_INACTIVE_FILE != 2 || LRU_ACTIVE_FILE != 3); > - return (l/2 == 1); > + return !!(l & LRU_FILE); > } > > struct per_cpu_pages { > Kosaki-san: Again, my doing. I agree that the calculation is a bit strange, but I wanted to "future-proof" this function in case we ever get to a value of '6' for the lru_list enum. In that case, the AND will evaluate to non-zero for what may not be a file LRU. Between the build time assertion and the division [which could just be a 'l >> 1', I suppose] we should be safe. Thanks, Lee -- 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