From mboxrd@z Thu Jan 1 00:00:00 1970 From: benh@kernel.crashing.org (Benjamin Herrenschmidt) Date: Sat, 27 Jul 2013 09:47:53 +1000 Subject: [GIT PULL] arm64 fixes for 3.11 In-Reply-To: References: <20130726155458.GA31613@arm.com> Message-ID: <1374882473.9200.33.camel@pasglop> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, 2013-07-26 at 12:54 -0700, Linus Torvalds wrote: > > *Some* other 64-bit architectures do 16k stack sizes. But neither > x86-64 nor powerpc do, afaik. Instead, they do irq stacks, which is > generally a better idea than having one big stack. Sadly you over estimated us here :-) We do 16K *and* irq stacks on 64-bit ... Remember our ABI with it's 112 bytes minimum per frame ? It's been a while since I've last audited our actual usage mind you, we *might* be able to reduce it but at this stage, since our typical configs use a 64K base page size, it's not a big deal (ie, it's not an order-N allocation). Cheers, Ben. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760368Ab3GZXso (ORCPT ); Fri, 26 Jul 2013 19:48:44 -0400 Received: from gate.crashing.org ([63.228.1.57]:51876 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750994Ab3GZXsn (ORCPT ); Fri, 26 Jul 2013 19:48:43 -0400 Message-ID: <1374882473.9200.33.camel@pasglop> Subject: Re: [GIT PULL] arm64 fixes for 3.11 From: Benjamin Herrenschmidt To: Linus Torvalds Cc: Catalin Marinas , Linux Kernel Mailing List , "linux-arm-kernel@lists.infradead.org" Date: Sat, 27 Jul 2013 09:47:53 +1000 In-Reply-To: References: <20130726155458.GA31613@arm.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.6.4-0ubuntu1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2013-07-26 at 12:54 -0700, Linus Torvalds wrote: > > *Some* other 64-bit architectures do 16k stack sizes. But neither > x86-64 nor powerpc do, afaik. Instead, they do irq stacks, which is > generally a better idea than having one big stack. Sadly you over estimated us here :-) We do 16K *and* irq stacks on 64-bit ... Remember our ABI with it's 112 bytes minimum per frame ? It's been a while since I've last audited our actual usage mind you, we *might* be able to reduce it but at this stage, since our typical configs use a 64K base page size, it's not a big deal (ie, it's not an order-N allocation). Cheers, Ben.