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=-3.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 611A2C2BA1A for ; Sun, 26 Apr 2020 07:26:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3DBE7206D4 for ; Sun, 26 Apr 2020 07:26:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="Re1ECLpO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726144AbgDZH0o (ORCPT ); Sun, 26 Apr 2020 03:26:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56394 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1725847AbgDZH0o (ORCPT ); Sun, 26 Apr 2020 03:26:44 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 96806C061A0C; Sun, 26 Apr 2020 00:26:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=CWSwm8Yeluzm8cpwZm/62btaRJCyoviiCLbacfabnGM=; b=Re1ECLpOnjCxMnMxw3nbFwqX2n aoIEpiDwCOhSXjRFQsAtKAUzFPfcZvScmnluhdPrGcpB4A73YnCcAK3X1/Udnt463gXZiWTPz/hdY Zm1qsK/TTQvahB8trR8xHhgpUygnDRg+nIVFpopoPErU2kCehwboKE+gZgzOWx7tGiBfdqF+7XjLQ nXGbVkpLeDiFJyDIB00acjlEnat0Goyv5mEX0AfFgXOl9BLdSgCkmDQwkWJK/Ym/oifDtpOlRDYDp XopgAFXT0HVE//Q7QrX3iZhO0PVRR0c/B26jlIRviJj+L4KI9zh60oN87/iGag0hjjm6rgmN2bu1K JDzqUHOw==; Received: from hch by bombadil.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jSbgY-00048J-Cx; Sun, 26 Apr 2020 07:26:42 +0000 Date: Sun, 26 Apr 2020 00:26:42 -0700 From: Christoph Hellwig To: ira.weiny@intel.com Cc: linux-kernel@vger.kernel.org, Andrew Morton , Dan Williams , Thomas Bogendoerfer , "James E.J. Bottomley" , Helge Deller , Benjamin Herrenschmidt , Paul Mackerras , "David S. Miller" , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H. Peter Anvin" , Dave Hansen , Andy Lutomirski , Peter Zijlstra , Chris Zankel , Max Filippov , linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, linux-xtensa@linux-xtensa.org Subject: Re: [PATCH 4/5] arch/kmap_atomic: Consolidate duplicate code Message-ID: <20200426072642.GB22024@infradead.org> References: <20200426055406.134198-1-ira.weiny@intel.com> <20200426055406.134198-5-ira.weiny@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200426055406.134198-5-ira.weiny@intel.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-parisc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-parisc@vger.kernel.org > diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c > index 4db13a6b9f3b..1cae4b911a33 100644 > --- a/arch/arc/mm/highmem.c > +++ b/arch/arc/mm/highmem.c > @@ -53,11 +53,10 @@ void *kmap_atomic(struct page *page) > { > int idx, cpu_idx; > unsigned long vaddr; > + void *addr = kmap_atomic_fast(page); > > - preempt_disable(); > - pagefault_disable(); > - if (!PageHighMem(page)) > - return page_address(page); > + if (addr) > + return addr; Wouldn't it make sense to just move kmap_atomic itelf to common code, and call out to a kmap_atomic_high for the highmem case, following the scheme in kmap? Same for the unmap side. That might require to support kmap_atomic_prot everywhere first, which sounds like a really good idea anyway, and would avoid the need for strange workaround in drm. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Date: Sun, 26 Apr 2020 07:26:42 +0000 Subject: Re: [PATCH 4/5] arch/kmap_atomic: Consolidate duplicate code Message-Id: <20200426072642.GB22024@infradead.org> List-Id: References: <20200426055406.134198-1-ira.weiny@intel.com> <20200426055406.134198-5-ira.weiny@intel.com> In-Reply-To: <20200426055406.134198-5-ira.weiny@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ira.weiny@intel.com Cc: Peter Zijlstra , Benjamin Herrenschmidt , Dave Hansen , linux-mips@vger.kernel.org, "James E.J. Bottomley" , Max Filippov , Paul Mackerras , "H. Peter Anvin" , sparclinux@vger.kernel.org, Dan Williams , Helge Deller , x86@kernel.org, linux-csky@vger.kernel.org, Ingo Molnar , linux-snps-arc@lists.infradead.org, linux-xtensa@linux-xtensa.org, Borislav Petkov , Andy Lutomirski , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, Chris Zankel , Thomas Bogendoerfer , linux-parisc@vger.kernel.org, linux-kernel@vger.kernel.org, Andrew Morton , linuxppc-dev@lists.ozlabs.org, "David S. Miller" > diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c > index 4db13a6b9f3b..1cae4b911a33 100644 > --- a/arch/arc/mm/highmem.c > +++ b/arch/arc/mm/highmem.c > @@ -53,11 +53,10 @@ void *kmap_atomic(struct page *page) > { > int idx, cpu_idx; > unsigned long vaddr; > + void *addr = kmap_atomic_fast(page); > > - preempt_disable(); > - pagefault_disable(); > - if (!PageHighMem(page)) > - return page_address(page); > + if (addr) > + return addr; Wouldn't it make sense to just move kmap_atomic itelf to common code, and call out to a kmap_atomic_high for the highmem case, following the scheme in kmap? Same for the unmap side. That might require to support kmap_atomic_prot everywhere first, which sounds like a really good idea anyway, and would avoid the need for strange workaround in drm. 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=-3.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 6CEC0C2BA1A for ; Sun, 26 Apr 2020 07:29:04 +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 1B2AD206D4 for ; Sun, 26 Apr 2020 07:29:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="Re1ECLpO" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1B2AD206D4 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 498zzx26wSzDqDr for ; Sun, 26 Apr 2020 17:29:01 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=bombadil.srs.infradead.org (client-ip=2607:7c80:54:e::133; helo=bombadil.infradead.org; envelope-from=batv+b4ccdff4e5217ceee7c0+6090+infradead.org+hch@bombadil.srs.infradead.org; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=bombadil.20170209 header.b=Re1ECLpO; dkim-atps=neutral Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) (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 498zxl3Jd1zDqTp for ; Sun, 26 Apr 2020 17:27:07 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=CWSwm8Yeluzm8cpwZm/62btaRJCyoviiCLbacfabnGM=; b=Re1ECLpOnjCxMnMxw3nbFwqX2n aoIEpiDwCOhSXjRFQsAtKAUzFPfcZvScmnluhdPrGcpB4A73YnCcAK3X1/Udnt463gXZiWTPz/hdY Zm1qsK/TTQvahB8trR8xHhgpUygnDRg+nIVFpopoPErU2kCehwboKE+gZgzOWx7tGiBfdqF+7XjLQ nXGbVkpLeDiFJyDIB00acjlEnat0Goyv5mEX0AfFgXOl9BLdSgCkmDQwkWJK/Ym/oifDtpOlRDYDp XopgAFXT0HVE//Q7QrX3iZhO0PVRR0c/B26jlIRviJj+L4KI9zh60oN87/iGag0hjjm6rgmN2bu1K JDzqUHOw==; Received: from hch by bombadil.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jSbgY-00048J-Cx; Sun, 26 Apr 2020 07:26:42 +0000 Date: Sun, 26 Apr 2020 00:26:42 -0700 From: Christoph Hellwig To: ira.weiny@intel.com Subject: Re: [PATCH 4/5] arch/kmap_atomic: Consolidate duplicate code Message-ID: <20200426072642.GB22024@infradead.org> References: <20200426055406.134198-1-ira.weiny@intel.com> <20200426055406.134198-5-ira.weiny@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200426055406.134198-5-ira.weiny@intel.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html 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: Peter Zijlstra , Dave Hansen , linux-mips@vger.kernel.org, "James E.J. Bottomley" , Max Filippov , Paul Mackerras , "H. Peter Anvin" , sparclinux@vger.kernel.org, Dan Williams , Helge Deller , x86@kernel.org, linux-csky@vger.kernel.org, Ingo Molnar , linux-snps-arc@lists.infradead.org, linux-xtensa@linux-xtensa.org, Borislav Petkov , Andy Lutomirski , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, Chris Zankel , Thomas Bogendoerfer , linux-parisc@vger.kernel.org, linux-kernel@vger.kernel.org, Andrew Morton , linuxppc-dev@lists.ozlabs.org, "David S. Miller" Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" > diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c > index 4db13a6b9f3b..1cae4b911a33 100644 > --- a/arch/arc/mm/highmem.c > +++ b/arch/arc/mm/highmem.c > @@ -53,11 +53,10 @@ void *kmap_atomic(struct page *page) > { > int idx, cpu_idx; > unsigned long vaddr; > + void *addr = kmap_atomic_fast(page); > > - preempt_disable(); > - pagefault_disable(); > - if (!PageHighMem(page)) > - return page_address(page); > + if (addr) > + return addr; Wouldn't it make sense to just move kmap_atomic itelf to common code, and call out to a kmap_atomic_high for the highmem case, following the scheme in kmap? Same for the unmap side. That might require to support kmap_atomic_prot everywhere first, which sounds like a really good idea anyway, and would avoid the need for strange workaround in drm. 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=-3.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 F201EC55191 for ; Sun, 26 Apr 2020 07:26:45 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 C15302084D for ; Sun, 26 Apr 2020 07:26:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="E6UTxZ8E" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C15302084D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-snps-arc-bounces+linux-snps-arc=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=OENs1M/tg4vHJBZS1yEvCCt4ahpwb3vA/XGM2WMOEE8=; b=E6UTxZ8EAW9Reu cc96RjJu1fFUIWYTTUIQXfj10zffSgfobIup/pG9y+q8V7JI+fm/vzqpXEZTysIGl+7FYSiueHKPG z42TLAR+tCdiU8v7zF3zhP9RD1Zshc+0I1QsQlCzrDA7yAct0spQI9Cm6VEheQS4IyfBbsfW7in86 1f2tfnnUZi2NmHgkwyDWWkU8m53HlpqS8nPE3RefojGfZvDsk9aMiGd0eXZgznBIj2BsWm5yn4B8M IIX4j0NfIjovKwkose8XiL7WxJRGJjCHt07Qzoq48kmHidFjtE8wqsqPlyhNweRt4MBY/wDbJtg84 o3CnJINY0K5NiL3aTY2A==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jSbga-00048e-CD; Sun, 26 Apr 2020 07:26:44 +0000 Received: from hch by bombadil.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jSbgY-00048J-Cx; Sun, 26 Apr 2020 07:26:42 +0000 Date: Sun, 26 Apr 2020 00:26:42 -0700 From: Christoph Hellwig To: ira.weiny@intel.com Subject: Re: [PATCH 4/5] arch/kmap_atomic: Consolidate duplicate code Message-ID: <20200426072642.GB22024@infradead.org> References: <20200426055406.134198-1-ira.weiny@intel.com> <20200426055406.134198-5-ira.weiny@intel.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200426055406.134198-5-ira.weiny@intel.com> 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: Peter Zijlstra , Benjamin Herrenschmidt , Dave Hansen , linux-mips@vger.kernel.org, "James E.J. Bottomley" , Max Filippov , Paul Mackerras , "H. Peter Anvin" , sparclinux@vger.kernel.org, Dan Williams , Helge Deller , x86@kernel.org, linux-csky@vger.kernel.org, Ingo Molnar , linux-snps-arc@lists.infradead.org, linux-xtensa@linux-xtensa.org, Borislav Petkov , Andy Lutomirski , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, Chris Zankel , Thomas Bogendoerfer , linux-parisc@vger.kernel.org, linux-kernel@vger.kernel.org, Andrew Morton , linuxppc-dev@lists.ozlabs.org, "David S. Miller" 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 > diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c > index 4db13a6b9f3b..1cae4b911a33 100644 > --- a/arch/arc/mm/highmem.c > +++ b/arch/arc/mm/highmem.c > @@ -53,11 +53,10 @@ void *kmap_atomic(struct page *page) > { > int idx, cpu_idx; > unsigned long vaddr; > + void *addr = kmap_atomic_fast(page); > > - preempt_disable(); > - pagefault_disable(); > - if (!PageHighMem(page)) > - return page_address(page); > + if (addr) > + return addr; Wouldn't it make sense to just move kmap_atomic itelf to common code, and call out to a kmap_atomic_high for the highmem case, following the scheme in kmap? Same for the unmap side. That might require to support kmap_atomic_prot everywhere first, which sounds like a really good idea anyway, and would avoid the need for strange workaround in drm. _______________________________________________ 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=-3.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 EA0BEC55196 for ; Sun, 26 Apr 2020 07:26:45 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 C07CE206D4 for ; Sun, 26 Apr 2020 07:26:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="MfkQdXW2" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C07CE206D4 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=WgTlu6wpyN93ZADP/xhLSPFANAm8OFJCzFDvt7pH4CM=; b=MfkQdXW26J9zpK 8PIVfXjbYWvh5hyvoqSc10M3mkeiUGcGE5u9E8Yd1EpW/BDzV/mEUiyQDjAEbuqj/NMaBkwlFA1by Lvr0FsFyz49Qn0DuaHmhj9rl7layO6q4U8QzD8zDn/ZydvKLmID3pML8pyBRAvtbIZv7gkrz7liUD CaZmGRRHGO5LMt8haAM+STj4JdciXLWgDcT2D3GCSphD36eDcSEQLbkju4pgKbUPvxPMCDWHxhOTG Yd7ulHooK4l/rHMtAYNdJWvsRJyO+167p8RO0b2mrrjJ18/luNyf+p+anV1ZJidClHmJZtZ8TbrE6 s7zrj1EvUJDUetQMKL9Q==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jSbga-00048r-Rd; Sun, 26 Apr 2020 07:26:44 +0000 Received: from hch by bombadil.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jSbgY-00048J-Cx; Sun, 26 Apr 2020 07:26:42 +0000 Date: Sun, 26 Apr 2020 00:26:42 -0700 From: Christoph Hellwig To: ira.weiny@intel.com Subject: Re: [PATCH 4/5] arch/kmap_atomic: Consolidate duplicate code Message-ID: <20200426072642.GB22024@infradead.org> References: <20200426055406.134198-1-ira.weiny@intel.com> <20200426055406.134198-5-ira.weiny@intel.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200426055406.134198-5-ira.weiny@intel.com> 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: Peter Zijlstra , Benjamin Herrenschmidt , Dave Hansen , linux-mips@vger.kernel.org, "James E.J. Bottomley" , Max Filippov , Paul Mackerras , "H. Peter Anvin" , sparclinux@vger.kernel.org, Dan Williams , Helge Deller , x86@kernel.org, linux-csky@vger.kernel.org, Ingo Molnar , linux-snps-arc@lists.infradead.org, linux-xtensa@linux-xtensa.org, Borislav Petkov , Andy Lutomirski , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, Chris Zankel , Thomas Bogendoerfer , linux-parisc@vger.kernel.org, linux-kernel@vger.kernel.org, Andrew Morton , linuxppc-dev@lists.ozlabs.org, "David S. Miller" Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org > diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c > index 4db13a6b9f3b..1cae4b911a33 100644 > --- a/arch/arc/mm/highmem.c > +++ b/arch/arc/mm/highmem.c > @@ -53,11 +53,10 @@ void *kmap_atomic(struct page *page) > { > int idx, cpu_idx; > unsigned long vaddr; > + void *addr = kmap_atomic_fast(page); > > - preempt_disable(); > - pagefault_disable(); > - if (!PageHighMem(page)) > - return page_address(page); > + if (addr) > + return addr; Wouldn't it make sense to just move kmap_atomic itelf to common code, and call out to a kmap_atomic_high for the highmem case, following the scheme in kmap? Same for the unmap side. That might require to support kmap_atomic_prot everywhere first, which sounds like a really good idea anyway, and would avoid the need for strange workaround in drm. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel