From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <467F6C8F.9040400@yahoo.com.au> Date: Mon, 25 Jun 2007 17:19:43 +1000 From: Nick Piggin MIME-Version: 1.0 Subject: Re: [patch 1/3] add the fsblock layer References: <20070624014528.GA17609@wotan.suse.de> <20070624014613.GB17609@wotan.suse.de> In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Andi Kleen Cc: Nick Piggin , Linux Kernel Mailing List , Linux Memory Management List , linux-fsdevel@vger.kernel.org List-ID: Andi Kleen wrote: > Nick Piggin writes: > > > [haven't read everything, just commenting on something that caught my eye] > > >>+struct fsblock { >>+ atomic_t count; >>+ union { >>+ struct { >>+ unsigned long flags; /* XXX: flags could be int for better packing */ > > > int is not supported by many architectures, but works on x86 at least. Yeah, that would be nice. We could actually use this for buffer_head as well, but saving 4% there isn't so important as saving 20% for fsblock :) > Hmm, could define a macro DECLARE_ATOMIC_BITMAP(maxbit) that expands to the smallest > possible type for each architecture. And a couple of ugly casts for set_bit et.al. > but those could be also hidden in macros. Should be relatively easy to do. Cool. It would probably be useful for other things as well. -- SUSE Labs, Novell Inc. -- 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