From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C8E05C433EF for ; Tue, 22 Mar 2022 03:07:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236020AbiCVDIy (ORCPT ); Mon, 21 Mar 2022 23:08:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51660 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235872AbiCVDIt (ORCPT ); Mon, 21 Mar 2022 23:08:49 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3B2E9140F4; Mon, 21 Mar 2022 20:07:23 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id BF37EB81B41; Tue, 22 Mar 2022 03:07:21 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 80126C340E8; Tue, 22 Mar 2022 03:07:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1647918440; bh=JbminCrwvlKeHI7BEmFEsF5mDATqt+IS8qjcZ0/Jt9M=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=QXAmVA5wzyUI2A1gidTxf5+Lo6mDAbigvc7Oy0OmXaaB60pzd2ZM3RZzXh1ONfLiQ rcm70kJ/Ci2YoNfEesX6/y+NDr/MfTm7yzMJcVfqf5rppfBhzFhpYm3soqnr8vyEqY 0T9J/oRiVAWY51zw2o99VDzbxSp85Gx2cfDifP5vWxNS/tMHx13Ea+2/y90cvg03l5 6gAp8I2yarUR5IZlxfxhCsGvLMrXZeLHenIZlvc706Alb8DGCG8hGWzfBl0t1Me22X omXtfJopIWR+aXYBRHLZKCZK3ZkqQ73ONWYFzfcorVZgEMzViOXN3wifI1BFd32Ulv JiY+QggjG5riw== Received: by mail-vs1-f41.google.com with SMTP id 2so9784745vse.4; Mon, 21 Mar 2022 20:07:20 -0700 (PDT) X-Gm-Message-State: AOAM531aCzh68XRbmaPpJ+FEO+ZW9rMf/PBCYllqnCNNjpVHOJJ2ZfBK NApFte2jWFdiHEXUbfg/fIdhYsGJQiSR/jFfPkU= X-Google-Smtp-Source: ABdhPJx4+oH0hOgpdvstgqFyVbmteIBIBzG7Uewe8HbwCzcGggSv3RFh+6z7krU1v8KMTHuDPkzMCzfD1G8XtTDEGEY= X-Received: by 2002:a05:6102:2e5:b0:325:30d7:c452 with SMTP id j5-20020a05610202e500b0032530d7c452mr1451473vsj.67.1647918439548; Mon, 21 Mar 2022 20:07:19 -0700 (PDT) MIME-Version: 1.0 References: <20220319142759.1026237-1-chenhuacai@loongson.cn> <20220319143817.1026708-1-chenhuacai@loongson.cn> <20220319143817.1026708-4-chenhuacai@loongson.cn> In-Reply-To: From: Huacai Chen Date: Tue, 22 Mar 2022 11:07:11 +0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH V8 11/22] LoongArch: Add process management To: Arnd Bergmann Cc: Andy Lutomirski , Thomas Gleixner , Peter Zijlstra , Andrew Morton , David Airlie , Jonathan Corbet , Linus Torvalds , linux-arch , "open list:DOCUMENTATION" , Linux Kernel Mailing List , Xuefeng Li , Yanteng Si , Jiaxun Yang , Huacai Chen Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Arnd, On Mon, Mar 21, 2022 at 4:43 PM Arnd Bergmann wrote: > > On Sat, Mar 19, 2022 at 3:38 PM Huacai Chen wrote: > > > +#ifdef CONFIG_PAGE_SIZE_64KB > > +#define THREAD_SIZE_ORDER (0) > > +#endif > > + > > +#define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER) > > +#define THREAD_MASK (THREAD_SIZE - 1UL) > > + > > Having a 64KB stack area is rather wasteful. I think you should use a sub-page > allocation in this configuration, or possibly disallow 64KB page configuration > entirely. > > Note that you have to use full pages when using CONFIG_VMAP_STACK, but > you don't seem to support that at the moment, so allocating only 16KB stacks > on a 64KB page config should still work. I think using a 16KB stack for all configurations (4KB/16KB/64KB) is the simplest way. Right? Huacai > > Arnd