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 X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 D0E98C4727E for ; Wed, 23 Sep 2020 14:33:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 92B5121D43 for ; Wed, 23 Sep 2020 14:33:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="pA5Hd7/w"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="qGRiwr69" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726819AbgIWOdW (ORCPT ); Wed, 23 Sep 2020 10:33:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33960 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726587AbgIWOdV (ORCPT ); Wed, 23 Sep 2020 10:33:21 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7B8F9C0613CE; Wed, 23 Sep 2020 07:33:21 -0700 (PDT) From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1600871599; 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: in-reply-to:in-reply-to:references:references; bh=htFCLJWsNhxoKbCNWhQS/6Kyz86LUNNWBiBq6qkBFyQ=; b=pA5Hd7/wYPJW36CTtNNTbOYCzRvXBsTbhCHBjjmQZ01hpagIyv/VcnxLW17kJqMxHoJumz z5+hv3BrOqb8U7x+bnWe3Vg7hjpdsIzhk0Jj3S1z+5+winumEs8KsUyf1K1TnGwBajSWcB LPdDuPzlUY6BQkUL/KCzLAeEkhIHNDaswPGDWAOJny+dzcHlZahNl7c2FSd1xp6gP0rEgj KzUlj0Dxhw0txRUSLaqWlErEiWSU9Sozf2/yRD5Qwp08ro8Q2KjAE/20gQBa42apztEBT8 SUzGb5WlY8s1AJc0khV/84NW02EhLXtT8nMIfQBdpZd1EmcFI7Hj8Ky6D6u98A== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1600871599; 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: in-reply-to:in-reply-to:references:references; bh=htFCLJWsNhxoKbCNWhQS/6Kyz86LUNNWBiBq6qkBFyQ=; b=qGRiwr69/8k8ntlbQpv0icecJVUI4PbZN1b5MTw/xOk+gHpAMJmHhEqUxn40L21XWDImxq PUiJwewr0xn47MAg== To: Linus Torvalds Cc: LKML , linux-arch , Paul McKenney , the arch/x86 maintainers , Sebastian Andrzej Siewior , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Daniel Bristot de Oliveira , Will Deacon , Andrew Morton , Linux-MM , Russell King , Linux ARM , Chris Zankel , Max Filippov , linux-xtensa@linux-xtensa.org, Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , David Airlie , Daniel Vetter , intel-gfx , dri-devel , Ard Biesheuvel , Herbert Xu , Vineet Gupta , "open list\:SYNOPSYS ARC ARCHITECTURE" , Arnd Bergmann , Guo Ren , 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 , "David S. Miller" , linux-sparc Subject: Re: [patch RFC 00/15] mm/highmem: Provide a preemptible variant of kmap_atomic & friends In-Reply-To: <87sgbbaq0y.fsf@nanos.tec.linutronix.de> References: <20200919091751.011116649@linutronix.de> <87mu1lc5mp.fsf@nanos.tec.linutronix.de> <87k0wode9a.fsf@nanos.tec.linutronix.de> <87eemwcpnq.fsf@nanos.tec.linutronix.de> <87a6xjd1dw.fsf@nanos.tec.linutronix.de> <87sgbbaq0y.fsf@nanos.tec.linutronix.de> Date: Wed, 23 Sep 2020 16:33:19 +0200 Message-ID: <877dska7gw.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Sep 21 2020 at 21:27, Thomas Gleixner wrote: > On Mon, Sep 21 2020 at 09:24, Linus Torvalds wrote: >> On Mon, Sep 21, 2020 at 12:39 AM Thomas Gleixner wrote: >> Maybe we really *could* call this new kmap functionality something >> like "kmap_percpu()" (or maybe "local" is good enough), and make it >> act like your RT code does for spinlocks - not disable preemption, but >> only disabling CPU migration. > > I"m all for it, but the scheduler people have opinions :) I just took the latest version of migrate disable patches https://lore.kernel.org/r/20200921163557.234036895@infradead.org removed the RT dependency on top of them and adopted the kmap stuff (addressing the various comments while at it and unbreaking ARM). I'm not going to post that until there is consensus about the general availability of migrate disable, but for those who want to play with it I've pushed the resulting combo out to: git://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git highmem For testing I've tweaked a few places to use the new _local() variants and it survived testing so far and I've verified that there is actual preemption which means zap/restore of the thread local kmaps. Thanks, tglx From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Gleixner Date: Wed, 23 Sep 2020 14:33:19 +0000 Subject: Re: [patch RFC 00/15] mm/highmem: Provide a preemptible variant of kmap_atomic & friends Message-Id: <877dska7gw.fsf@nanos.tec.linutronix.de> List-Id: References: <20200919091751.011116649@linutronix.de> <87mu1lc5mp.fsf@nanos.tec.linutronix.de> <87k0wode9a.fsf@nanos.tec.linutronix.de> <87eemwcpnq.fsf@nanos.tec.linutronix.de> <87a6xjd1dw.fsf@nanos.tec.linutronix.de> <87sgbbaq0y.fsf@nanos.tec.linutronix.de> In-Reply-To: <87sgbbaq0y.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Linus Torvalds Cc: Juri Lelli , Peter Zijlstra , Sebastian Andrzej Siewior , dri-devel , linux-mips@vger.kernel.org, Ben Segall , Max Filippov , Guo Ren , linux-sparc , Vincent Chen , Will Deacon , Ard Biesheuvel , linux-arch , Vincent Guittot , Herbert Xu , Michael Ellerman , the arch/x86 maintainers , Russell King , linux-csky@vger.kernel.org, David Airlie , Mel Gorman , "open list:SYNOPSYS ARC ARCHITECTURE" , linux-xtensa@linux-xtensa.org, Paul McKenney , intel-gfx , linuxppc-dev , Steven Rostedt , Rodrigo Vivi , Dietmar Eggemann , Linux ARM , Chris Zankel , Michal Simek , Thomas Bogendoerfer , Nick Hu , Linux-MM , Vineet Gupta , LKML , Arnd Bergmann , Paul Mackerras , Andrew Morton , Daniel Bristot de Oliveira , "David S. Miller" , Greentime Hu On Mon, Sep 21 2020 at 21:27, Thomas Gleixner wrote: > On Mon, Sep 21 2020 at 09:24, Linus Torvalds wrote: >> On Mon, Sep 21, 2020 at 12:39 AM Thomas Gleixner wrote: >> Maybe we really *could* call this new kmap functionality something >> like "kmap_percpu()" (or maybe "local" is good enough), and make it >> act like your RT code does for spinlocks - not disable preemption, but >> only disabling CPU migration. > > I"m all for it, but the scheduler people have opinions :) I just took the latest version of migrate disable patches https://lore.kernel.org/r/20200921163557.234036895@infradead.org removed the RT dependency on top of them and adopted the kmap stuff (addressing the various comments while at it and unbreaking ARM). I'm not going to post that until there is consensus about the general availability of migrate disable, but for those who want to play with it I've pushed the resulting combo out to: git://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git highmem For testing I've tweaked a few places to use the new _local() variants and it survived testing so far and I've verified that there is actual preemption which means zap/restore of the thread local kmaps. Thanks, tglx 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 X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 95012C4727F for ; Wed, 23 Sep 2020 14:33:24 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 1069123899 for ; Wed, 23 Sep 2020 14:33:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="pA5Hd7/w"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="qGRiwr69" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1069123899 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 390B56B005C; Wed, 23 Sep 2020 10:33:23 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 319876B005D; Wed, 23 Sep 2020 10:33:23 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 194166B0062; Wed, 23 Sep 2020 10:33:23 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0085.hostedemail.com [216.40.44.85]) by kanga.kvack.org (Postfix) with ESMTP id EE5E76B005C for ; Wed, 23 Sep 2020 10:33:22 -0400 (EDT) Received: from smtpin07.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id A6867AC07 for ; Wed, 23 Sep 2020 14:33:22 +0000 (UTC) X-FDA: 77294569044.07.boys82_0f0376527157 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin07.hostedemail.com (Postfix) with ESMTP id 80EC81849A3A1 for ; Wed, 23 Sep 2020 14:33:22 +0000 (UTC) X-HE-Tag: boys82_0f0376527157 X-Filterd-Recvd-Size: 5385 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by imf47.hostedemail.com (Postfix) with ESMTP for ; Wed, 23 Sep 2020 14:33:21 +0000 (UTC) From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1600871599; 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: in-reply-to:in-reply-to:references:references; bh=htFCLJWsNhxoKbCNWhQS/6Kyz86LUNNWBiBq6qkBFyQ=; b=pA5Hd7/wYPJW36CTtNNTbOYCzRvXBsTbhCHBjjmQZ01hpagIyv/VcnxLW17kJqMxHoJumz z5+hv3BrOqb8U7x+bnWe3Vg7hjpdsIzhk0Jj3S1z+5+winumEs8KsUyf1K1TnGwBajSWcB LPdDuPzlUY6BQkUL/KCzLAeEkhIHNDaswPGDWAOJny+dzcHlZahNl7c2FSd1xp6gP0rEgj KzUlj0Dxhw0txRUSLaqWlErEiWSU9Sozf2/yRD5Qwp08ro8Q2KjAE/20gQBa42apztEBT8 SUzGb5WlY8s1AJc0khV/84NW02EhLXtT8nMIfQBdpZd1EmcFI7Hj8Ky6D6u98A== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1600871599; 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: in-reply-to:in-reply-to:references:references; bh=htFCLJWsNhxoKbCNWhQS/6Kyz86LUNNWBiBq6qkBFyQ=; b=qGRiwr69/8k8ntlbQpv0icecJVUI4PbZN1b5MTw/xOk+gHpAMJmHhEqUxn40L21XWDImxq PUiJwewr0xn47MAg== To: Linus Torvalds Cc: LKML , linux-arch , Paul McKenney , the arch/x86 maintainers , Sebastian Andrzej Siewior , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Daniel Bristot de Oliveira , Will Deacon , Andrew Morton , Linux-MM , Russell King , Linux ARM , Chris Zankel , Max Filippov , linux-xtensa@linux-xtensa.org, Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , David Airlie , Daniel Vetter , intel-gfx , dri-devel , Ard Biesheuvel , Herbert Xu , Vineet Gupta , "open list\:SYNOPSYS ARC ARCHITECTURE" , Arnd Bergmann , Guo Ren , 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 , "David S. Miller" , linux-sparc Subject: Re: [patch RFC 00/15] mm/highmem: Provide a preemptible variant of kmap_atomic & friends In-Reply-To: <87sgbbaq0y.fsf@nanos.tec.linutronix.de> References: <20200919091751.011116649@linutronix.de> <87mu1lc5mp.fsf@nanos.tec.linutronix.de> <87k0wode9a.fsf@nanos.tec.linutronix.de> <87eemwcpnq.fsf@nanos.tec.linutronix.de> <87a6xjd1dw.fsf@nanos.tec.linutronix.de> <87sgbbaq0y.fsf@nanos.tec.linutronix.de> Date: Wed, 23 Sep 2020 16:33:19 +0200 Message-ID: <877dska7gw.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain 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: On Mon, Sep 21 2020 at 21:27, Thomas Gleixner wrote: > On Mon, Sep 21 2020 at 09:24, Linus Torvalds wrote: >> On Mon, Sep 21, 2020 at 12:39 AM Thomas Gleixner wrote: >> Maybe we really *could* call this new kmap functionality something >> like "kmap_percpu()" (or maybe "local" is good enough), and make it >> act like your RT code does for spinlocks - not disable preemption, but >> only disabling CPU migration. > > I"m all for it, but the scheduler people have opinions :) I just took the latest version of migrate disable patches https://lore.kernel.org/r/20200921163557.234036895@infradead.org removed the RT dependency on top of them and adopted the kmap stuff (addressing the various comments while at it and unbreaking ARM). I'm not going to post that until there is consensus about the general availability of migrate disable, but for those who want to play with it I've pushed the resulting combo out to: git://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git highmem For testing I've tweaked a few places to use the new _local() variants and it survived testing so far and I've verified that there is actual preemption which means zap/restore of the thread local kmaps. Thanks, tglx 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 X-Spam-Level: X-Spam-Status: No, score=-8.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 D3EFFC4363D for ; Wed, 23 Sep 2020 14:39:34 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (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 E558721D43 for ; Wed, 23 Sep 2020 14:39:33 +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="pA5Hd7/w"; 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dkim=pass header.d=linutronix.de header.i=@linutronix.de header.a=ed25519-sha256 header.s=2020e header.b=qGRiwr69; dkim-atps=neutral Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4BxLJS5JGmzDqW2 for ; Thu, 24 Sep 2020 00:33:28 +1000 (AEST) From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1600871599; 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: in-reply-to:in-reply-to:references:references; bh=htFCLJWsNhxoKbCNWhQS/6Kyz86LUNNWBiBq6qkBFyQ=; b=pA5Hd7/wYPJW36CTtNNTbOYCzRvXBsTbhCHBjjmQZ01hpagIyv/VcnxLW17kJqMxHoJumz z5+hv3BrOqb8U7x+bnWe3Vg7hjpdsIzhk0Jj3S1z+5+winumEs8KsUyf1K1TnGwBajSWcB LPdDuPzlUY6BQkUL/KCzLAeEkhIHNDaswPGDWAOJny+dzcHlZahNl7c2FSd1xp6gP0rEgj KzUlj0Dxhw0txRUSLaqWlErEiWSU9Sozf2/yRD5Qwp08ro8Q2KjAE/20gQBa42apztEBT8 SUzGb5WlY8s1AJc0khV/84NW02EhLXtT8nMIfQBdpZd1EmcFI7Hj8Ky6D6u98A== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1600871599; 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: in-reply-to:in-reply-to:references:references; bh=htFCLJWsNhxoKbCNWhQS/6Kyz86LUNNWBiBq6qkBFyQ=; b=qGRiwr69/8k8ntlbQpv0icecJVUI4PbZN1b5MTw/xOk+gHpAMJmHhEqUxn40L21XWDImxq PUiJwewr0xn47MAg== To: Linus Torvalds Subject: Re: [patch RFC 00/15] mm/highmem: Provide a preemptible variant of kmap_atomic & friends In-Reply-To: <87sgbbaq0y.fsf@nanos.tec.linutronix.de> References: <20200919091751.011116649@linutronix.de> <87mu1lc5mp.fsf@nanos.tec.linutronix.de> <87k0wode9a.fsf@nanos.tec.linutronix.de> <87eemwcpnq.fsf@nanos.tec.linutronix.de> <87a6xjd1dw.fsf@nanos.tec.linutronix.de> <87sgbbaq0y.fsf@nanos.tec.linutronix.de> Date: Wed, 23 Sep 2020 16:33:19 +0200 Message-ID: <877dska7gw.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Juri Lelli , Peter Zijlstra , Sebastian Andrzej Siewior , Joonas Lahtinen , dri-devel , linux-mips@vger.kernel.org, Ben Segall , Max Filippov , Guo Ren , linux-sparc , Vincent Chen , Will Deacon , Ard Biesheuvel , linux-arch , Vincent Guittot , Herbert Xu , the arch/x86 maintainers , Russell King , linux-csky@vger.kernel.org, David Airlie , Mel Gorman , "open list:SYNOPSYS ARC ARCHITECTURE" , linux-xtensa@linux-xtensa.org, Paul McKenney , intel-gfx , linuxppc-dev , Steven Rostedt , Jani Nikula , Rodrigo Vivi , Dietmar Eggemann , Linux ARM , Chris Zankel , Michal Simek , Thomas Bogendoerfer , Nick Hu , Linux-MM , Vineet Gupta , LKML , Arnd Bergmann , Daniel Vetter , Paul Mackerras , Andrew Morton , Daniel Bristot de Oliveira , "David S. Miller" , Greentime Hu Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Mon, Sep 21 2020 at 21:27, Thomas Gleixner wrote: > On Mon, Sep 21 2020 at 09:24, Linus Torvalds wrote: >> On Mon, Sep 21, 2020 at 12:39 AM Thomas Gleixner wrote: >> Maybe we really *could* call this new kmap functionality something >> like "kmap_percpu()" (or maybe "local" is good enough), and make it >> act like your RT code does for spinlocks - not disable preemption, but >> only disabling CPU migration. > > I"m all for it, but the scheduler people have opinions :) I just took the latest version of migrate disable patches https://lore.kernel.org/r/20200921163557.234036895@infradead.org removed the RT dependency on top of them and adopted the kmap stuff (addressing the various comments while at it and unbreaking ARM). I'm not going to post that until there is consensus about the general availability of migrate disable, but for those who want to play with it I've pushed the resulting combo out to: git://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git highmem For testing I've tweaked a few places to use the new _local() variants and it survived testing so far and I've verified that there is actual preemption which means zap/restore of the thread local kmaps. Thanks, tglx 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 X-Spam-Level: X-Spam-Status: No, score=-10.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 61173C4363D for ; Wed, 23 Sep 2020 14:33:31 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 CBF4121D43 for ; Wed, 23 Sep 2020 14:33:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="K+qdCZNX"; 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bh=htFCLJWsNhxoKbCNWhQS/6Kyz86LUNNWBiBq6qkBFyQ=; b=pA5Hd7/wYPJW36CTtNNTbOYCzRvXBsTbhCHBjjmQZ01hpagIyv/VcnxLW17kJqMxHoJumz z5+hv3BrOqb8U7x+bnWe3Vg7hjpdsIzhk0Jj3S1z+5+winumEs8KsUyf1K1TnGwBajSWcB LPdDuPzlUY6BQkUL/KCzLAeEkhIHNDaswPGDWAOJny+dzcHlZahNl7c2FSd1xp6gP0rEgj KzUlj0Dxhw0txRUSLaqWlErEiWSU9Sozf2/yRD5Qwp08ro8Q2KjAE/20gQBa42apztEBT8 SUzGb5WlY8s1AJc0khV/84NW02EhLXtT8nMIfQBdpZd1EmcFI7Hj8Ky6D6u98A== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1600871599; 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: in-reply-to:in-reply-to:references:references; bh=htFCLJWsNhxoKbCNWhQS/6Kyz86LUNNWBiBq6qkBFyQ=; b=qGRiwr69/8k8ntlbQpv0icecJVUI4PbZN1b5MTw/xOk+gHpAMJmHhEqUxn40L21XWDImxq PUiJwewr0xn47MAg== To: Linus Torvalds Subject: Re: [patch RFC 00/15] mm/highmem: Provide a preemptible variant of kmap_atomic & friends In-Reply-To: <87sgbbaq0y.fsf@nanos.tec.linutronix.de> References: <20200919091751.011116649@linutronix.de> <87mu1lc5mp.fsf@nanos.tec.linutronix.de> <87k0wode9a.fsf@nanos.tec.linutronix.de> <87eemwcpnq.fsf@nanos.tec.linutronix.de> <87a6xjd1dw.fsf@nanos.tec.linutronix.de> <87sgbbaq0y.fsf@nanos.tec.linutronix.de> Date: Wed, 23 Sep 2020 16:33:19 +0200 Message-ID: <877dska7gw.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200923_103321_342483_4BCA1BB1 X-CRM114-Status: GOOD ( 14.21 ) X-BeenThere: linux-snps-arc@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on Synopsys ARC Processors List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Juri Lelli , Peter Zijlstra , Benjamin Herrenschmidt , Sebastian Andrzej Siewior , Joonas Lahtinen , dri-devel , linux-mips@vger.kernel.org, Ben Segall , Max Filippov , Guo Ren , linux-sparc , Vincent Chen , Will Deacon , Ard Biesheuvel , linux-arch , Vincent Guittot , Herbert Xu , Michael Ellerman , the arch/x86 maintainers , Russell King , linux-csky@vger.kernel.org, David Airlie , Mel Gorman , "open list:SYNOPSYS ARC ARCHITECTURE" , linux-xtensa@linux-xtensa.org, Paul McKenney , intel-gfx , linuxppc-dev , Steven Rostedt , Jani Nikula , Rodrigo Vivi , Dietmar Eggemann , Linux ARM , Chris Zankel , Michal Simek , Thomas Bogendoerfer , Nick Hu , Linux-MM , Vineet Gupta , LKML , Arnd Bergmann , Daniel Vetter , Paul Mackerras , Andrew Morton , Daniel Bristot de Oliveira , "David S. Miller" , Greentime Hu Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-snps-arc" Errors-To: linux-snps-arc-bounces+linux-snps-arc=archiver.kernel.org@lists.infradead.org On Mon, Sep 21 2020 at 21:27, Thomas Gleixner wrote: > On Mon, Sep 21 2020 at 09:24, Linus Torvalds wrote: >> On Mon, Sep 21, 2020 at 12:39 AM Thomas Gleixner wrote: >> Maybe we really *could* call this new kmap functionality something >> like "kmap_percpu()" (or maybe "local" is good enough), and make it >> act like your RT code does for spinlocks - not disable preemption, but >> only disabling CPU migration. > > I"m all for it, but the scheduler people have opinions :) I just took the latest version of migrate disable patches https://lore.kernel.org/r/20200921163557.234036895@infradead.org removed the RT dependency on top of them and adopted the kmap stuff (addressing the various comments while at it and unbreaking ARM). I'm not going to post that until there is consensus about the general availability of migrate disable, but for those who want to play with it I've pushed the resulting combo out to: git://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git highmem For testing I've tweaked a few places to use the new _local() variants and it survived testing so far and I've verified that there is actual preemption which means zap/restore of the thread local kmaps. Thanks, tglx _______________________________________________ linux-snps-arc mailing list linux-snps-arc@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-snps-arc 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 X-Spam-Level: X-Spam-Status: No, score=-10.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 73E83C4363D for ; Wed, 23 Sep 2020 14:34:34 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 1AD95206FB for ; 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bh=htFCLJWsNhxoKbCNWhQS/6Kyz86LUNNWBiBq6qkBFyQ=; b=pA5Hd7/wYPJW36CTtNNTbOYCzRvXBsTbhCHBjjmQZ01hpagIyv/VcnxLW17kJqMxHoJumz z5+hv3BrOqb8U7x+bnWe3Vg7hjpdsIzhk0Jj3S1z+5+winumEs8KsUyf1K1TnGwBajSWcB LPdDuPzlUY6BQkUL/KCzLAeEkhIHNDaswPGDWAOJny+dzcHlZahNl7c2FSd1xp6gP0rEgj KzUlj0Dxhw0txRUSLaqWlErEiWSU9Sozf2/yRD5Qwp08ro8Q2KjAE/20gQBa42apztEBT8 SUzGb5WlY8s1AJc0khV/84NW02EhLXtT8nMIfQBdpZd1EmcFI7Hj8Ky6D6u98A== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1600871599; 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: in-reply-to:in-reply-to:references:references; bh=htFCLJWsNhxoKbCNWhQS/6Kyz86LUNNWBiBq6qkBFyQ=; b=qGRiwr69/8k8ntlbQpv0icecJVUI4PbZN1b5MTw/xOk+gHpAMJmHhEqUxn40L21XWDImxq PUiJwewr0xn47MAg== To: Linus Torvalds Subject: Re: [patch RFC 00/15] mm/highmem: Provide a preemptible variant of kmap_atomic & friends In-Reply-To: <87sgbbaq0y.fsf@nanos.tec.linutronix.de> References: <20200919091751.011116649@linutronix.de> <87mu1lc5mp.fsf@nanos.tec.linutronix.de> <87k0wode9a.fsf@nanos.tec.linutronix.de> <87eemwcpnq.fsf@nanos.tec.linutronix.de> <87a6xjd1dw.fsf@nanos.tec.linutronix.de> <87sgbbaq0y.fsf@nanos.tec.linutronix.de> Date: Wed, 23 Sep 2020 16:33:19 +0200 Message-ID: <877dska7gw.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200923_103321_342483_4BCA1BB1 X-CRM114-Status: GOOD ( 14.21 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Juri Lelli , Peter Zijlstra , Benjamin Herrenschmidt , Sebastian Andrzej Siewior , Joonas Lahtinen , dri-devel , linux-mips@vger.kernel.org, Ben Segall , Max Filippov , Guo Ren , linux-sparc , Vincent Chen , Will Deacon , Ard Biesheuvel , linux-arch , Vincent Guittot , Herbert Xu , Michael Ellerman , the arch/x86 maintainers , Russell King , linux-csky@vger.kernel.org, David Airlie , Mel Gorman , "open list:SYNOPSYS ARC ARCHITECTURE" , linux-xtensa@linux-xtensa.org, Paul McKenney , intel-gfx , linuxppc-dev , Steven Rostedt , Jani Nikula , Rodrigo Vivi , Dietmar Eggemann , Linux ARM , Chris Zankel , Michal Simek , Thomas Bogendoerfer , Nick Hu , Linux-MM , Vineet Gupta , LKML , Arnd Bergmann , Daniel Vetter , Paul Mackerras , Andrew Morton , Daniel Bristot de Oliveira , "David S. Miller" , Greentime Hu Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Sep 21 2020 at 21:27, Thomas Gleixner wrote: > On Mon, Sep 21 2020 at 09:24, Linus Torvalds wrote: >> On Mon, Sep 21, 2020 at 12:39 AM Thomas Gleixner wrote: >> Maybe we really *could* call this new kmap functionality something >> like "kmap_percpu()" (or maybe "local" is good enough), and make it >> act like your RT code does for spinlocks - not disable preemption, but >> only disabling CPU migration. > > I"m all for it, but the scheduler people have opinions :) I just took the latest version of migrate disable patches https://lore.kernel.org/r/20200921163557.234036895@infradead.org removed the RT dependency on top of them and adopted the kmap stuff (addressing the various comments while at it and unbreaking ARM). I'm not going to post that until there is consensus about the general availability of migrate disable, but for those who want to play with it I've pushed the resulting combo out to: git://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git highmem For testing I've tweaked a few places to use the new _local() variants and it survived testing so far and I've verified that there is actual preemption which means zap/restore of the thread local kmaps. Thanks, tglx _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel 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 X-Spam-Level: X-Spam-Status: No, score=-8.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 4DFEAC2D0E2 for ; Thu, 24 Sep 2020 07:19:24 +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 E6B8F20936 for ; Thu, 24 Sep 2020 07:19:23 +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="pA5Hd7/w"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="qGRiwr69" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E6B8F20936 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linutronix.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 5527A6EAB6; Thu, 24 Sep 2020 07:19:10 +0000 (UTC) Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by gabe.freedesktop.org (Postfix) with ESMTPS id A6B596E9BC; Wed, 23 Sep 2020 14:33:21 +0000 (UTC) From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1600871599; 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: in-reply-to:in-reply-to:references:references; bh=htFCLJWsNhxoKbCNWhQS/6Kyz86LUNNWBiBq6qkBFyQ=; b=pA5Hd7/wYPJW36CTtNNTbOYCzRvXBsTbhCHBjjmQZ01hpagIyv/VcnxLW17kJqMxHoJumz z5+hv3BrOqb8U7x+bnWe3Vg7hjpdsIzhk0Jj3S1z+5+winumEs8KsUyf1K1TnGwBajSWcB LPdDuPzlUY6BQkUL/KCzLAeEkhIHNDaswPGDWAOJny+dzcHlZahNl7c2FSd1xp6gP0rEgj KzUlj0Dxhw0txRUSLaqWlErEiWSU9Sozf2/yRD5Qwp08ro8Q2KjAE/20gQBa42apztEBT8 SUzGb5WlY8s1AJc0khV/84NW02EhLXtT8nMIfQBdpZd1EmcFI7Hj8Ky6D6u98A== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1600871599; 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: in-reply-to:in-reply-to:references:references; bh=htFCLJWsNhxoKbCNWhQS/6Kyz86LUNNWBiBq6qkBFyQ=; b=qGRiwr69/8k8ntlbQpv0icecJVUI4PbZN1b5MTw/xOk+gHpAMJmHhEqUxn40L21XWDImxq PUiJwewr0xn47MAg== To: Linus Torvalds Subject: Re: [patch RFC 00/15] mm/highmem: Provide a preemptible variant of kmap_atomic & friends In-Reply-To: <87sgbbaq0y.fsf@nanos.tec.linutronix.de> References: <20200919091751.011116649@linutronix.de> <87mu1lc5mp.fsf@nanos.tec.linutronix.de> <87k0wode9a.fsf@nanos.tec.linutronix.de> <87eemwcpnq.fsf@nanos.tec.linutronix.de> <87a6xjd1dw.fsf@nanos.tec.linutronix.de> <87sgbbaq0y.fsf@nanos.tec.linutronix.de> Date: Wed, 23 Sep 2020 16:33:19 +0200 Message-ID: <877dska7gw.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 X-Mailman-Approved-At: Thu, 24 Sep 2020 07:19:09 +0000 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Juri Lelli , Peter Zijlstra , Sebastian Andrzej Siewior , dri-devel , linux-mips@vger.kernel.org, Ben Segall , Max Filippov , Guo Ren , linux-sparc , Vincent Chen , Will Deacon , Ard Biesheuvel , linux-arch , Vincent Guittot , Herbert Xu , Michael Ellerman , the arch/x86 maintainers , Russell King , linux-csky@vger.kernel.org, David Airlie , Mel Gorman , "open list:SYNOPSYS ARC ARCHITECTURE" , linux-xtensa@linux-xtensa.org, Paul McKenney , intel-gfx , linuxppc-dev , Steven Rostedt , Rodrigo Vivi , Dietmar Eggemann , Linux ARM , Chris Zankel , Michal Simek , Thomas Bogendoerfer , Nick Hu , Linux-MM , Vineet Gupta , LKML , Arnd Bergmann , Paul Mackerras , Andrew Morton , Daniel Bristot de Oliveira , "David S. Miller" , Greentime Hu Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Mon, Sep 21 2020 at 21:27, Thomas Gleixner wrote: > On Mon, Sep 21 2020 at 09:24, Linus Torvalds wrote: >> On Mon, Sep 21, 2020 at 12:39 AM Thomas Gleixner wrote: >> Maybe we really *could* call this new kmap functionality something >> like "kmap_percpu()" (or maybe "local" is good enough), and make it >> act like your RT code does for spinlocks - not disable preemption, but >> only disabling CPU migration. > > I"m all for it, but the scheduler people have opinions :) I just took the latest version of migrate disable patches https://lore.kernel.org/r/20200921163557.234036895@infradead.org removed the RT dependency on top of them and adopted the kmap stuff (addressing the various comments while at it and unbreaking ARM). I'm not going to post that until there is consensus about the general availability of migrate disable, but for those who want to play with it I've pushed the resulting combo out to: git://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git highmem For testing I've tweaked a few places to use the new _local() variants and it survived testing so far and I've verified that there is actual preemption which means zap/restore of the thread local kmaps. Thanks, tglx _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel 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 X-Spam-Level: X-Spam-Status: No, score=-8.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 D4345C4741F for ; Wed, 23 Sep 2020 14:33:23 +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 87B6D206FB for ; Wed, 23 Sep 2020 14:33:23 +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="pA5Hd7/w"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="qGRiwr69" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 87B6D206FB 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 D0DA76E9BC; Wed, 23 Sep 2020 14:33:22 +0000 (UTC) Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by gabe.freedesktop.org (Postfix) with ESMTPS id A6B596E9BC; Wed, 23 Sep 2020 14:33:21 +0000 (UTC) From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1600871599; 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: in-reply-to:in-reply-to:references:references; bh=htFCLJWsNhxoKbCNWhQS/6Kyz86LUNNWBiBq6qkBFyQ=; b=pA5Hd7/wYPJW36CTtNNTbOYCzRvXBsTbhCHBjjmQZ01hpagIyv/VcnxLW17kJqMxHoJumz z5+hv3BrOqb8U7x+bnWe3Vg7hjpdsIzhk0Jj3S1z+5+winumEs8KsUyf1K1TnGwBajSWcB LPdDuPzlUY6BQkUL/KCzLAeEkhIHNDaswPGDWAOJny+dzcHlZahNl7c2FSd1xp6gP0rEgj KzUlj0Dxhw0txRUSLaqWlErEiWSU9Sozf2/yRD5Qwp08ro8Q2KjAE/20gQBa42apztEBT8 SUzGb5WlY8s1AJc0khV/84NW02EhLXtT8nMIfQBdpZd1EmcFI7Hj8Ky6D6u98A== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1600871599; 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: in-reply-to:in-reply-to:references:references; bh=htFCLJWsNhxoKbCNWhQS/6Kyz86LUNNWBiBq6qkBFyQ=; b=qGRiwr69/8k8ntlbQpv0icecJVUI4PbZN1b5MTw/xOk+gHpAMJmHhEqUxn40L21XWDImxq PUiJwewr0xn47MAg== To: Linus Torvalds In-Reply-To: <87sgbbaq0y.fsf@nanos.tec.linutronix.de> References: <20200919091751.011116649@linutronix.de> <87mu1lc5mp.fsf@nanos.tec.linutronix.de> <87k0wode9a.fsf@nanos.tec.linutronix.de> <87eemwcpnq.fsf@nanos.tec.linutronix.de> <87a6xjd1dw.fsf@nanos.tec.linutronix.de> <87sgbbaq0y.fsf@nanos.tec.linutronix.de> Date: Wed, 23 Sep 2020 16:33:19 +0200 Message-ID: <877dska7gw.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Subject: Re: [Intel-gfx] [patch RFC 00/15] mm/highmem: Provide a preemptible variant of kmap_atomic & friends 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 , Peter Zijlstra , Benjamin Herrenschmidt , Sebastian Andrzej Siewior , dri-devel , linux-mips@vger.kernel.org, Ben Segall , Max Filippov , Guo Ren , linux-sparc , Vincent Chen , Will Deacon , Ard Biesheuvel , linux-arch , Herbert Xu , Michael Ellerman , the arch/x86 maintainers , Russell King , linux-csky@vger.kernel.org, David Airlie , Mel Gorman , "open list:SYNOPSYS ARC ARCHITECTURE" , linux-xtensa@linux-xtensa.org, Paul McKenney , intel-gfx , linuxppc-dev , Steven Rostedt , Dietmar Eggemann , Linux ARM , Chris Zankel , Michal Simek , Thomas Bogendoerfer , Nick Hu , Linux-MM , Vineet Gupta , LKML , Arnd Bergmann , Paul Mackerras , Andrew Morton , Daniel Bristot de Oliveira , "David S. Miller" , Greentime Hu Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Mon, Sep 21 2020 at 21:27, Thomas Gleixner wrote: > On Mon, Sep 21 2020 at 09:24, Linus Torvalds wrote: >> On Mon, Sep 21, 2020 at 12:39 AM Thomas Gleixner wrote: >> Maybe we really *could* call this new kmap functionality something >> like "kmap_percpu()" (or maybe "local" is good enough), and make it >> act like your RT code does for spinlocks - not disable preemption, but >> only disabling CPU migration. > > I"m all for it, but the scheduler people have opinions :) I just took the latest version of migrate disable patches https://lore.kernel.org/r/20200921163557.234036895@infradead.org removed the RT dependency on top of them and adopted the kmap stuff (addressing the various comments while at it and unbreaking ARM). I'm not going to post that until there is consensus about the general availability of migrate disable, but for those who want to play with it I've pushed the resulting combo out to: git://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git highmem For testing I've tweaked a few places to use the new _local() variants and it survived testing so far and I've verified that there is actual preemption which means zap/restore of the thread local kmaps. Thanks, tglx _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx