From patchwork Thu Nov 3 20:23:12 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Rutland X-Patchwork-Id: 80730 Delivered-To: patch@linaro.org Received: by 10.140.97.247 with SMTP id m110csp826656qge; Thu, 3 Nov 2016 13:27:07 -0700 (PDT) X-Received: by 10.98.80.2 with SMTP id e2mr20171204pfb.183.1478204827578; Thu, 03 Nov 2016 13:27:07 -0700 (PDT) Return-Path: Received: from bombadil.infradead.org (bombadil.infradead.org. [2001:1868:205::9]) by mx.google.com with ESMTPS id e17si11514300pgj.133.2016.11.03.13.27.07 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 03 Nov 2016 13:27:07 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org designates 2001:1868:205::9 as permitted sender) client-ip=2001:1868:205::9; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org designates 2001:1868:205::9 as permitted sender) smtp.mailfrom=linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1c2OaI-0003L4-2d; Thu, 03 Nov 2016 20:26:02 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1c2OYb-0001Gh-68 for linux-arm-kernel@lists.infradead.org; Thu, 03 Nov 2016 20:24:19 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id D815315BE; Thu, 3 Nov 2016 13:23:53 -0700 (PDT) Received: from localhost.localdomain (usa-sjc-mx-foss1.foss.arm.com [217.140.101.70]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 3E7CE3F318; Thu, 3 Nov 2016 13:23:52 -0700 (PDT) From: Mark Rutland To: linux-arm-kernel@lists.infradead.org Subject: [PATCHv2 10/11] arm64: assembler: introduce ldr_this_cpu Date: Thu, 3 Nov 2016 20:23:12 +0000 Message-Id: <1478204593-29145-11-git-send-email-mark.rutland@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1478204593-29145-1-git-send-email-mark.rutland@arm.com> References: <1478204593-29145-1-git-send-email-mark.rutland@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20161103_132417_390134_0D3817FC X-CRM114-Status: GOOD ( 10.24 ) X-Spam-Score: -8.3 (--------) X-Spam-Report: SpamAssassin version 3.4.0 on bombadil.infradead.org summary: Content analysis details: (-8.3 points) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at http://www.dnswl.org/, high trust [217.140.101.70 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -1.4 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mark.rutland@arm.com, lorenzo.pieralisi@arm.com, keescook@chromium.org, ard.biesheuvel@linaro.org, catalin.marinas@arm.com, suzuki.poulose@arm.com, will.deacon@arm.com, takahiro.akashi@linaro.org, james.morse@arm.com, luto@kernel.org, labbott@redhat.com MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org Shortly we will want to load a percpu variable in the return from userspace path. We can save an instruction by folding the addition of the percpu offset into the load instruction, and this patch adds a new helper to do so. At the same time, we clean up this_cpu_ptr for consistency. As with {adr,ldr,str}_l, we change the template to take the destination register first, and name this dst. Secondly, we rename the macro to adr_this_cpu, following the scheme of adr_l, and matching the newly added ldr_this_cpu. Signed-off-by: Mark Rutland Tested-by: Laura Abbott Cc: Ard Biesheuvel Cc: Catalin Marinas Cc: James Morse Cc: Will Deacon --- arch/arm64/include/asm/assembler.h | 19 +++++++++++++++---- arch/arm64/kernel/entry.S | 2 +- 2 files changed, 16 insertions(+), 5 deletions(-) -- 2.7.4 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index 28bfe61..128a9ca 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -202,14 +202,25 @@ lr .req x30 // link register .endm /* + * @dst: Result of per_cpu(sym, smp_processor_id()) * @sym: The name of the per-cpu variable - * @reg: Result of per_cpu(sym, smp_processor_id()) * @tmp: scratch register */ - .macro this_cpu_ptr, sym, reg, tmp - adr_l \reg, \sym + .macro adr_this_cpu, dst, sym, tmp + adr_l \dst, \sym mrs \tmp, tpidr_el1 - add \reg, \reg, \tmp + add \dst, \dst, \tmp + .endm + + /* + * @dst: Result of READ_ONCE(per_cpu(sym, smp_processor_id())) + * @sym: The name of the per-cpu variable + * @tmp: scratch register + */ + .macro ldr_this_cpu dst, sym, tmp + adr_l \dst, \sym + mrs \tmp, tpidr_el1 + ldr \dst, [\dst, \tmp] .endm /* diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index 223d54a..2d4c83b 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -200,7 +200,7 @@ alternative_else_nop_endif cmp x25, tsk b.ne 9998f - this_cpu_ptr irq_stack, x25, x26 + adr_this_cpu x25, irq_stack, x26 mov x26, #IRQ_STACK_START_SP add x26, x25, x26