From patchwork Tue Nov 3 09:27:17 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 11876785 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 00A01C6379D for ; Tue, 3 Nov 2020 10:33:37 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 925772242A for ; Tue, 3 Nov 2020 10:33:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="qxeKab/j"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="sa3bXF2K" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 925772242A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linutronix.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 4494D6EC63; Tue, 3 Nov 2020 10:33:33 +0000 (UTC) Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by gabe.freedesktop.org (Postfix) with ESMTPS id 991F16EC4F; Tue, 3 Nov 2020 10:33:31 +0000 (UTC) Message-Id: <20201103095857.078043987@linutronix.de> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1604399609; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: references:references; bh=ut1GkVw4OXMSCtChDMtmqVv6FlrafPsAPVPH5qh/+W4=; b=qxeKab/jnzonAYIBxQj7C+lU1MXIOtv9AUxIqLZgMNOheS1/C1ppYtMhiRGWGILT0p9BRX pgQSNcMXtj2Uc5P/cIyFA85cG3zt2PWv30XyG8pKoOND+ze18oEqwDagKsMk4iFbkxn6w3 nHjpZ+/5f9nyGALGAnCDWfSOLvmz6+kVq3EXJm/nem1WmvK7IfNuhg+QYUzzvNXpCI5JCV /zpQKKIRbeU1LpPLNe05AoFKzjsDBQG2wAWha8c2KiRVj55HfMkJaQutHQqfH87MuhQYm+ dvAy7X7H2pEzrttiZjmlLL/Ut6jFrU2e2uklduyXACJvrBvG+GDZzRfAbFAKGQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1604399609; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: references:references; bh=ut1GkVw4OXMSCtChDMtmqVv6FlrafPsAPVPH5qh/+W4=; b=sa3bXF2K349r2Sx437G+viH7NII4z1vmSjqFyQiLWboorIUK0oCNgpdHH/H8Y0GgaZiyhO PJb8yq1jh8Mfa0Dw== Date: Tue, 03 Nov 2020 10:27:17 +0100 From: Thomas Gleixner To: LKML References: <20201103092712.714480842@linutronix.de> MIME-Version: 1.0 Subject: [Intel-gfx] [patch V3 05/37] asm-generic: Provide kmap_size.h X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Juri Lelli , linux-aio@kvack.org, Peter Zijlstra , Benjamin Herrenschmidt , Sebastian Andrzej Siewior , dri-devel@lists.freedesktop.org, virtualization@lists.linux-foundation.org, Ben Segall , Chris Mason , Huang Rui , Paul Mackerras , Gerd Hoffmann , Daniel Bristot de Oliveira , sparclinux@vger.kernel.org, Vincent Chen , Christoph Hellwig , Paul McKenney , Max Filippov , Michael Ellerman , x86@kernel.org, Russell King , linux-csky@vger.kernel.org, Ingo Molnar , David Airlie , VMware Graphics , Mel Gorman , nouveau@lists.freedesktop.org, Dave Airlie , linux-snps-arc@lists.infradead.org, Ben Skeggs , linux-xtensa@linux-xtensa.org, Arnd Bergmann , intel-gfx@lists.freedesktop.org, Roland Scheidegger , Josef Bacik , Steven Rostedt , Linus Torvalds , Alexander Viro , spice-devel@lists.freedesktop.org, David Sterba , Dietmar Eggemann , linux-arm-kernel@lists.infradead.org, Chris Zankel , Michal Simek , Thomas Bogendoerfer , Nick Hu , linux-mm@kvack.org, Vineet Gupta , linux-mips@vger.kernel.org, Christian Koenig , Benjamin LaHaise , linux-fsdevel@vger.kernel.org, Andrew Morton , linuxppc-dev@lists.ozlabs.org, "David S. Miller" , linux-btrfs@vger.kernel.org, Greentime Hu Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" kmap_types.h is a misnomer because the old atomic MAP based array does not exist anymore and the whole indirection of architectures including kmap_types.h is inconinstent and does not allow to provide guard page debugging for this misfeature. Add a common header file which defines the mapping stack size for all architectures. Will be used when converting architectures over to a generic kmap_local/atomic implementation. The array size is chosen with the following constraints in mind: - The deepest nest level in one context is 3 according to code inspection. - The worst case nesting for the upcoming reemptible version would be: 2 maps in task context and a fault inside 2 maps in the fault handler 3 maps in softirq 2 maps in interrupt So a total of 16 is sufficient and probably overestimated. Signed-off-by: Thomas Gleixner Acked-by: Arnd Bergmann --- V3: New patch --- include/asm-generic/Kbuild | 1 + include/asm-generic/kmap_size.h | 12 ++++++++++++ 2 files changed, 13 insertions(+) --- a/include/asm-generic/Kbuild +++ b/include/asm-generic/Kbuild @@ -31,6 +31,7 @@ mandatory-y += irq_regs.h mandatory-y += irq_work.h mandatory-y += kdebug.h mandatory-y += kmap_types.h +mandatory-y += kmap_size.h mandatory-y += kprobes.h mandatory-y += linkage.h mandatory-y += local.h --- /dev/null +++ b/include/asm-generic/kmap_size.h @@ -0,0 +1,12 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_GENERIC_KMAP_SIZE_H +#define _ASM_GENERIC_KMAP_SIZE_H + +/* For debug this provides guard pages between the maps */ +#ifdef CONFIG_DEBUG_HIGHMEM +# define KM_MAX_IDX 33 +#else +# define KM_MAX_IDX 16 +#endif + +#endif