From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: rename *MEMALLOC flags (was: Re: [RFC][PATCH 3/4] deadlock prevention core) From: Peter Zijlstra In-Reply-To: <33037.81.207.0.53.1155396500.squirrel@81.207.0.53> References: <20060812141415.30842.78695.sendpatchset@lappy> <20060812141445.30842.47336.sendpatchset@lappy> <44DDE8B6.8000900@garzik.org> <1155395201.13508.44.camel@lappy> <33037.81.207.0.53.1155396500.squirrel@81.207.0.53> Content-Type: text/plain Date: Sat, 12 Aug 2006 17:34:36 +0200 Message-Id: <1155396877.13508.58.camel@lappy> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Indan Zupancic Cc: Jeff Garzik , linux-mm@kvack.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, Evgeniy Polyakov , Daniel Phillips , Rik van Riel , David Miller List-ID: On Sat, 2006-08-12 at 17:28 +0200, Indan Zupancic wrote: > On Sat, August 12, 2006 17:06, Peter Zijlstra said: > > On Sat, 2006-08-12 at 10:41 -0400, Jeff Garzik wrote: > >> Peter Zijlstra wrote: > >> > Index: linux-2.6/include/linux/gfp.h > >> > =================================================================== > >> > --- linux-2.6.orig/include/linux/gfp.h 2006-08-12 12:56:06.000000000 +0200 > >> > +++ linux-2.6/include/linux/gfp.h 2006-08-12 12:56:09.000000000 +0200 > >> > @@ -46,6 +46,7 @@ struct vm_area_struct; > >> > #define __GFP_ZERO ((__force gfp_t)0x8000u)/* Return zeroed page on success */ > >> > #define __GFP_NOMEMALLOC ((__force gfp_t)0x10000u) /* Don't use emergency reserves */ > >> > #define __GFP_HARDWALL ((__force gfp_t)0x20000u) /* Enforce hardwall cpuset memory allocs > >> */ > >> > +#define __GFP_MEMALLOC ((__force gfp_t)0x40000u) /* Use emergency reserves */ > >> > >> This symbol name has nothing to do with its purpose. The entire area of > >> code you are modifying could be described as having something to do with > >> 'memalloc'. > >> > >> GFP_EMERGENCY or GFP_USE_RESERVES or somesuch would be a far better > >> symbol name. > >> > >> I recognize that is matches with GFP_NOMEMALLOC, but that doesn't change > >> the situation anyway. In fact, a cleanup patch to rename GFP_NOMEMALLOC > >> would be nice. > > > > I'm rather bad at picking names, but here goes: > > > > PF_MEMALLOC -> PF_EMERGALLOC > > __GFP_NOMEMALLOC -> __GFP_NOEMERGALLOC > > __GFP_MEMALLOC -> __GFP_EMERGALLOC SOCK_MEMALLOC -> SOCK_EMERGALLOC > > > > Is that suitable and shall I prepare patches? Or do we want more ppl to > > chime in and have a few more rounds? > > Pardon my ignorance, but if we're doing cleanup anyway, why not use only one flag instead of two? > Why is __GFP_NOMEMALLOC needed when not setting __GFP_MEMALLOC could mean the same? Or else what > is the expected behaviour if both flags are set? __GFP_NOMEMALLOC is most authorative; its use is (afaik) to negate PF_MEMALLOC. I agree that having both seems odd, but I haven't spend any significant time on trying to find a 'nicer' solution. -- 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