From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f173.google.com (mail-pd0-f173.google.com [209.85.192.173]) by kanga.kvack.org (Postfix) with ESMTP id B90296B0031 for ; Mon, 2 Dec 2013 23:59:47 -0500 (EST) Received: by mail-pd0-f173.google.com with SMTP id p10so19533941pdj.32 for ; Mon, 02 Dec 2013 20:59:47 -0800 (PST) Received: from smtp.codeaurora.org (smtp.codeaurora.org. [198.145.11.231]) by mx.google.com with ESMTPS id nu5si10276770pbc.268.2013.12.02.20.59.45 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 02 Dec 2013 20:59:46 -0800 (PST) Message-ID: <529D653F.3090401@codeaurora.org> Date: Mon, 02 Dec 2013 20:59:43 -0800 From: Laura Abbott MIME-Version: 1.0 Subject: Re: [RFC PATCH 3/4] mm/vmalloc.c: Allow lowmem to be tracked in vmalloc References: <1384212412-21236-1-git-send-email-lauraa@codeaurora.org> <1384212412-21236-4-git-send-email-lauraa@codeaurora.org> <52850C37.1080506@sr71.net> <5285A896.3030204@codeaurora.org> <20131126144541.6b16979b77f927f6d945ab60@linux-foundation.org> In-Reply-To: <20131126144541.6b16979b77f927f6d945ab60@linux-foundation.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Dave Hansen , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, Neeti Desai On 11/26/2013 2:45 PM, Andrew Morton wrote: > So yes, it would be prudent to be worried about is_vmalloc_addr() > performance at the outset. > > Couldn't is_vmalloc_addr() just be done with a plain old bitmap? It > would consume 128kbytes to manage a 4G address space, and 1/8th of a meg > isn't much. > Yes, I came to the same conclusion after realizing I needed something similar to fix up proc/kcore.c . I plan to go with the bitmap for the next patch version. Laura -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation -- 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