From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753092AbZBPRa1 (ORCPT ); Mon, 16 Feb 2009 12:30:27 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752761AbZBPRaF (ORCPT ); Mon, 16 Feb 2009 12:30:05 -0500 Received: from fg-out-1718.google.com ([72.14.220.154]:5830 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752752AbZBPRaB (ORCPT ); Mon, 16 Feb 2009 12:30:01 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type :content-transfer-encoding; b=vYQfe5sDSQ7KW75i49Jt1UaPF6UxB62UqQ29PVQPK7YBg4Sxeolm2cnC+6tJSSOtl/ 3fA5ymr6V9NuxYocLCOS4FHhREWL3j3GdTl95yS0iNwoSkL9Wvk4/5TN3mcwu9CiRudz 9iieat3XY2QYOJNnyLEMu1CjlBnu9fEhI0mFM= MIME-Version: 1.0 In-Reply-To: <1234801952.20430.33.camel@localhost> References: <1234272104-10211-1-git-send-email-kirill@shutemov.name> <84144f020902100535i4d626a9fj8cbb305120cf332a@mail.gmail.com> <20090210134651.GA5115@epbyminw8406h.minsk.epam.com> <20090216135643.GA6927@cmpxchg.org> <1234801952.20430.33.camel@localhost> Date: Mon, 16 Feb 2009 19:29:59 +0200 X-Google-Sender-Auth: dd10a8823dc3381e Message-ID: <84144f020902160929k67ce1881p959646a326bb3f40@mail.gmail.com> Subject: Re: [PATCH] Export symbol ksize() From: Pekka Enberg To: Joe Perches Cc: Johannes Weiner , "Kirill A. Shutemov" , Christoph Lameter , Matt Mackall , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-crypto@vger.kernel.org, Herbert Xu , Geert.Uytterhoeven@sonycom.com Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2009-02-16 at 14:56 +0100, Johannes Weiner wrote: >> One problem is that zeroing ksize() >> bytes can have an overhead of nearly twice the actual allocation size. On Mon, Feb 16, 2009 at 6:32 PM, Joe Perches wrote: > A possible good thing is when linux has a > mechanism to use known zeroed memory in > kzalloc or kcalloc, it's already good to go. Hmm, kzfree() is not going to be all that common operation so there won't be that many known zeroed regions and I suspect tracking them will have more overhead than just doing the memset().