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: 11876703 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3343B6A2 for ; Tue, 3 Nov 2020 10:33:44 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id D530422409 for ; Tue, 3 Nov 2020 10:33:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (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 D530422409 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linutronix.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 9FBAB6B007B; Tue, 3 Nov 2020 05:33:32 -0500 (EST) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 901FD6B0073; Tue, 3 Nov 2020 05:33:32 -0500 (EST) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 690BC6B0073; Tue, 3 Nov 2020 05:33:32 -0500 (EST) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0146.hostedemail.com [216.40.44.146]) by kanga.kvack.org (Postfix) with ESMTP id 2788D6B007B for ; Tue, 3 Nov 2020 05:33:32 -0500 (EST) Received: from smtpin24.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id C42B7181AC9BF for ; Tue, 3 Nov 2020 10:33:31 +0000 (UTC) X-FDA: 77442745422.24.wire42_190ba5a272b7 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin24.hostedemail.com (Postfix) with ESMTP id 8CD051A4A0; Tue, 3 Nov 2020 10:33:31 +0000 (UTC) X-Spam-Summary: 1,0,0,df959b4e1968d9ae,d41d8cd98f00b204,tglx@linutronix.de,,RULES_HIT:41:152:355:379:800:960:973:988:989:1183:1260:1277:1311:1313:1314:1345:1437:1515:1516:1518:1535:1541:1593:1594:1711:1730:1747:1777:1792:1978:1981:2194:2199:2393:2559:2562:2693:2904:3138:3139:3140:3141:3142:3353:3865:3866:3867:3868:3870:3871:4250:4605:5007:6261:6653:6742:6743:8603:10004:10400:11026:11232:11473:11658:11914:12043:12160:12296:12297:12438:13069:13161:13229:13311:13357:14096:14097:14181:14659:14721:21080:21433:21451:21627:21740:30012:30054,0,RBL:193.142.43.55:@linutronix.de:.lbl8.mailshell.net-64.100.201.201 62.2.6.100;04yg9dokpme3ko1487ckkzmc3j5s6yc438x1dc1wgpmqbokho9d6ap611k57u35.k4w8c4t9b6syca13f7rzws7s58p6usw7s75dfjxfb4i5mjuy68fwdr1w9t8afz4.r-lbl8.mailshell.net-223.238.255.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:69,LUA_SUMMARY:none X-HE-Tag: wire42_190ba5a272b7 X-Filterd-Recvd-Size: 5859 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by imf16.hostedemail.com (Postfix) with ESMTP; Tue, 3 Nov 2020 10:33:30 +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 Cc: Linus Torvalds , Peter Zijlstra , Paul McKenney , Christoph Hellwig , Sebastian Andrzej Siewior , Andrew Morton , linux-mm@kvack.org, Alexander Viro , Benjamin LaHaise , linux-fsdevel@vger.kernel.org, linux-aio@kvack.org, Chris Mason , Josef Bacik , David Sterba , linux-btrfs@vger.kernel.org, x86@kernel.org, Vineet Gupta , linux-snps-arc@lists.infradead.org, Russell King , Arnd Bergmann , linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, Michal Simek , Thomas Bogendoerfer , linux-mips@vger.kernel.org, Nick Hu , Greentime Hu , Vincent Chen , Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , linuxppc-dev@lists.ozlabs.org, "David S. Miller" , sparclinux@vger.kernel.org, Chris Zankel , Max Filippov , linux-xtensa@linux-xtensa.org, Ingo Molnar , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Daniel Bristot de Oliveira , Christian Koenig , Huang Rui , David Airlie , Daniel Vetter , dri-devel@lists.freedesktop.org, VMware Graphics , Roland Scheidegger , Dave Airlie , Gerd Hoffmann , virtualization@lists.linux-foundation.org, spice-devel@lists.freedesktop.org, Ben Skeggs , nouveau@lists.freedesktop.org, Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , intel-gfx@lists.freedesktop.org Subject: [patch V3 05/37] asm-generic: Provide kmap_size.h References: <20201103092712.714480842@linutronix.de> MIME-Version: 1.0 Content-transfer-encoding: 8-bit X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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