From patchwork Wed Jun 25 15:40:24 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steve Capper X-Patchwork-Id: 4421541 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 0D523BEECB for ; Wed, 25 Jun 2014 15:44:14 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 3BCB420394 for ; Wed, 25 Jun 2014 15:44:13 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C6EE620395 for ; Wed, 25 Jun 2014 15:44:11 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1WzpL2-0002yt-Ta; Wed, 25 Jun 2014 15:42:20 +0000 Received: from merlin.infradead.org ([2001:4978:20e::2]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1WzpK0-0002JB-Cr for linux-arm-kernel@bombadil.infradead.org; Wed, 25 Jun 2014 15:41:16 +0000 Received: from mail-we0-f172.google.com ([74.125.82.172]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1WzpJx-00054J-0n for linux-arm-kernel@lists.infradead.org; Wed, 25 Jun 2014 15:41:15 +0000 Received: by mail-we0-f172.google.com with SMTP id u57so2241192wes.31 for ; Wed, 25 Jun 2014 08:40:47 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=uEye2P2cQZkpDIFVqDn/xmSDLYmE5NQYaR6BJq/XuNg=; b=YfB+VyZbvvfZuuJfPLCpq6t6COr0LET/So9rfWlLhGubtxUk4OP1AJyroYPC6KnWXw 6GhUmqplbfYFEeYyzbRtJdwF4gA9YMGQXKb0Ce1tUyb5P1uNwWnnVKDOSXyJ+xkyq6Xj Dv39J5GMlWSJAEg9AT3jrIecar8P03Go2A0CFkL6j+OxarorNGfG3bAOgsfYkJyNfpxy 6P0OPV/bHJIvXorwSAFKx2ZWCZhgDwk9QKgcuPKNG+6JUHOpb9T/iv4JUzANwgVCiZje nZwDRdXkypRgjLrSvbfoUwVp9MYqIzamuEXfcjRv7Mwuy5yep80gaVGmZDXFUxekFnYb Axow== X-Gm-Message-State: ALoCoQkZCp4A7rBVgPtkZw5DdLZNUHA3d75Im1Az/nmsvnufRDUKkbSjtFk950CJ+M3Jz8Z4oGhH X-Received: by 10.194.158.164 with SMTP id wv4mr4318532wjb.124.1403710845245; Wed, 25 Jun 2014 08:40:45 -0700 (PDT) Received: from marmot.wormnet.eu (marmot.wormnet.eu. [188.246.204.87]) by mx.google.com with ESMTPSA id i3sm54967269wiz.13.2014.06.25.08.40.44 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 25 Jun 2014 08:40:44 -0700 (PDT) From: Steve Capper To: linux-arm-kernel@lists.infradead.org, catalin.marinas@arm.com, linux@arm.linux.org.uk, linux-arch@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 6/6] arm64: mm: Enable RCU fast_gup Date: Wed, 25 Jun 2014 16:40:24 +0100 Message-Id: <1403710824-24340-7-git-send-email-steve.capper@linaro.org> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1403710824-24340-1-git-send-email-steve.capper@linaro.org> References: <1403710824-24340-1-git-send-email-steve.capper@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140625_114113_240747_3D574BD8 X-CRM114-Status: GOOD ( 13.21 ) X-Spam-Score: -2.6 (--) Cc: anders.roxell@linaro.org, peterz@infradead.org, gary.robertson@linaro.org, will.deacon@arm.com, Steve Capper , akpm@linux-foundation.org, christoffer.dall@linaro.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Activate the RCU fast_gup for ARM64. We also need to force THP splits to broadcast an IPI s.t. we block in the fast_gup page walker. As THP splits are comparatively rare, this should not lead to a noticeable performance degradation. Some pre-requisite functions pud_write and pud_page are also added. Signed-off-by: Steve Capper --- arch/arm64/Kconfig | 3 +++ arch/arm64/include/asm/pgtable.h | 11 ++++++++++- arch/arm64/mm/flush.c | 19 +++++++++++++++++++ 3 files changed, 32 insertions(+), 1 deletion(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index e1d2eef..d6fcb8e 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -102,6 +102,9 @@ config GENERIC_CALIBRATE_DELAY config ZONE_DMA def_bool y +config HAVE_RCU_GUP + def_bool y + config ARCH_DMA_ADDR_T_64BIT def_bool y diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index e0ccceb..62510f7 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -237,7 +237,13 @@ static inline pmd_t pte_pmd(pte_t pte) #ifdef CONFIG_TRANSPARENT_HUGEPAGE #define pmd_trans_huge(pmd) (pmd_val(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT)) #define pmd_trans_splitting(pmd) pte_special(pmd_pte(pmd)) -#endif +#ifdef CONFIG_HAVE_RCU_TABLE_FREE +#define __HAVE_ARCH_PMDP_SPLITTING_FLUSH +struct vm_area_struct; +void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address, + pmd_t *pmdp); +#endif /* CONFIG_HAVE_RCU_TABLE_FREE */ +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ #define pmd_young(pmd) pte_young(pmd_pte(pmd)) #define pmd_wrprotect(pmd) pte_pmd(pte_wrprotect(pmd_pte(pmd))) @@ -258,6 +264,7 @@ static inline pmd_t pte_pmd(pte_t pte) #define mk_pmd(page,prot) pfn_pmd(page_to_pfn(page),prot) #define pmd_page(pmd) pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK)) +#define pud_write(pud) pmd_write(__pmd(pud_val(pud))) #define pud_pfn(pud) (((pud_val(pud) & PUD_MASK) & PHYS_MASK) >> PAGE_SHIFT) #define set_pmd_at(mm, addr, pmdp, pmd) set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd)) @@ -345,6 +352,8 @@ static inline pmd_t *pud_page_vaddr(pud_t pud) return __va(pud_val(pud) & PHYS_MASK & (s32)PAGE_MASK); } +#define pud_page(pud) pmd_page(__pmd(pud_val(pud))) + #endif /* CONFIG_ARM64_64K_PAGES */ /* to find an entry in a page-table-directory */ diff --git a/arch/arm64/mm/flush.c b/arch/arm64/mm/flush.c index e4193e3..ddf96c1 100644 --- a/arch/arm64/mm/flush.c +++ b/arch/arm64/mm/flush.c @@ -103,3 +103,22 @@ EXPORT_SYMBOL(flush_dcache_page); */ EXPORT_SYMBOL(flush_cache_all); EXPORT_SYMBOL(flush_icache_range); + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +#ifdef CONFIG_HAVE_RCU_TABLE_FREE +static void thp_splitting_flush_sync(void *arg) +{ +} + +void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address, + pmd_t *pmdp) +{ + pmd_t pmd = pmd_mksplitting(*pmdp); + VM_BUG_ON(address & ~PMD_MASK); + set_pmd_at(vma->vm_mm, address, pmdp, pmd); + + /* dummy IPI to serialise against fast_gup */ + smp_call_function(thp_splitting_flush_sync, NULL, 1); +} +#endif /* CONFIG_HAVE_RCU_TABLE_FREE */ +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */