From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1L0yPs-0004EI-7f for qemu-devel@nongnu.org; Fri, 14 Nov 2008 08:08:52 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1L0yPq-0004Ci-J9 for qemu-devel@nongnu.org; Fri, 14 Nov 2008 08:08:51 -0500 Received: from [199.232.76.173] (port=48345 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1L0yPq-0004CX-8v for qemu-devel@nongnu.org; Fri, 14 Nov 2008 08:08:50 -0500 Received: from mail2.shareable.org ([80.68.89.115]:54301) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1L0yPq-0004xh-9o for qemu-devel@nongnu.org; Fri, 14 Nov 2008 08:08:50 -0500 Date: Fri, 14 Nov 2008 13:08:45 +0000 From: Jamie Lokier Subject: Re: [Qemu-devel] [PATCH, v2] Rewrite mmap_find_vma() to work fine on 64-bit hosts with 32-bit targets Message-ID: <20081114130845.GA11975@shareable.org> References: <1223892640-15545-11-git-send-email-kirill@shutemov.name> <20081111005317.GA1215@shareable.org> <20081114122356.GA4943@epbyminw8406h.minsk.epam.com> <200811141251.38759.paul@codesourcery.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200811141251.38759.paul@codesourcery.com> Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paul Brook Cc: "Kirill A. Shutemov" , qemu-devel@nongnu.org Paul Brook wrote: > It's a basic binary search. The problem with it being that as with > any other binary search it relies on being able to do "probes". In > this case that involves mapping and unmapping the region, which I'd > expect to be fairly high overhead. But much less overhead than probing every page address as the current linear search does. The linear algorithm also does a map+unmap in its probes. That's the point. -- Jamie