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=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 80D21C04AAF for ; Tue, 21 May 2019 17:22:21 +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 48BF12173E for ; Tue, 21 May 2019 17:22:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="j0eQ5w8q" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 48BF12173E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com 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:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=fGJo3bDW+k0BC5fXrfKBLvzbLcEb25nbsdy2TNbCBHY=; b=j0eQ5w8qSS9tdwtl0sLwl9Y0cv scXtt5cQClX6XJIhQX1Bi/Ea3qQ7A+ymTqFyYmnFZv3wZTp1hIWFtbPZZEpoRJCVTQIrz39JmCB1C tbgzoHqiqr449Dr1MKOBwllfD9XUH1npa6nhuaprDqSBFStDUoD8Evh9VZEuNFBbY+l12rJDCQ7j/ SOt2tPjyt7K3NlqZrasKS2TVR/fbljegw6pCHQ1dTpG/XMLcGeMCtE7kUhszOeej/OvbhMa73wOuC p33G4sEZ8RZ6O0I3fWWNJsOYK0gAoCdKSVcW15ngmluPRnqA/0R4LjxIpwLUAVK3Ib6Op+GtLQm1P c3lAJ4Iw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hT8Sx-0001qs-Jd; Tue, 21 May 2019 17:22:19 +0000 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70] helo=foss.arm.com) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hT8Sc-0001Oz-On for linux-arm-kernel@lists.infradead.org; Tue, 21 May 2019 17:22:01 +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 AEA4115A2; Tue, 21 May 2019 10:21:57 -0700 (PDT) Received: from e108454-lin.cambridge.arm.com (e108454-lin.cambridge.arm.com [10.1.196.50]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 76F4A3F718; Tue, 21 May 2019 10:21:55 -0700 (PDT) From: Julien Grall To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu Subject: [PATCH v5 2/3] arch/arm64: fpsimd: Introduce fpsimd_save_and_flush_cpu_state() and use it Date: Tue, 21 May 2019 18:21:38 +0100 Message-Id: <20190521172139.21277-3-julien.grall@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190521172139.21277-1-julien.grall@arm.com> References: <20190521172139.21277-1-julien.grall@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190521_102158_941226_103E56D5 X-CRM114-Status: GOOD ( 17.40 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: ard.biesheuvel@linaro.org, julien.thierry@arm.com, marc.zyngier@arm.com, catalin.marinas@arm.com, suzuki.poulose@arm.com, will.deacon@arm.com, christoffer.dall@arm.com, Julien Grall , james.morse@arm.com, Dave.Martin@arm.com MIME-Version: 1.0 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 The only external user of fpsimd_save() and fpsimd_flush_cpu_state() is the KVM FPSIMD code. A following patch will introduce a mechanism to acquire owernship of the FPSIMD/SVE context for performing context management operations. Rather than having to export the new helpers to get/put the context, we can just introduce a new function to combine fpsimd_save() and fpsimd_flush_cpu_state(). This has also the advantage to remove any external call of fpsimd_save() and fpsimd_flush_cpu_state(), so they can be turned static. Lastly, the new function can also be used in the PM notifier. Signed-off-by: Julien Grall Reviewed-by: Dave Martin --- kernel_neon_begin() does not use fpsimd_save_and_flush_cpu_state() because the next patch will modify the function to also grab the FPSIMD/SVE context. Changes in v4: - Remove newline before the new prototype - Add Dave's reviewed-by Changes in v3: - Rework the commit message - Move the prototype of fpsimd_save_and_flush_cpu_state() further down in the header - Remove comment in kvm_arch_vcpu_put_fp() Changes in v2: - Patch added --- arch/arm64/include/asm/fpsimd.h | 4 +--- arch/arm64/kernel/fpsimd.c | 17 +++++++++++++---- arch/arm64/kvm/fpsimd.c | 4 +--- 3 files changed, 15 insertions(+), 10 deletions(-) diff --git a/arch/arm64/include/asm/fpsimd.h b/arch/arm64/include/asm/fpsimd.h index b73d12fcc7f9..4154851c21ab 100644 --- a/arch/arm64/include/asm/fpsimd.h +++ b/arch/arm64/include/asm/fpsimd.h @@ -48,8 +48,6 @@ struct task_struct; extern void fpsimd_save_state(struct user_fpsimd_state *state); extern void fpsimd_load_state(struct user_fpsimd_state *state); -extern void fpsimd_save(void); - extern void fpsimd_thread_switch(struct task_struct *next); extern void fpsimd_flush_thread(void); @@ -63,7 +61,7 @@ extern void fpsimd_bind_state_to_cpu(struct user_fpsimd_state *state, void *sve_state, unsigned int sve_vl); extern void fpsimd_flush_task_state(struct task_struct *target); -extern void fpsimd_flush_cpu_state(void); +extern void fpsimd_save_and_flush_cpu_state(void); /* Maximum VL that SVE VL-agnostic software can transparently support */ #define SVE_VL_ARCH_MAX 0x100 diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index a38bf74bcca8..6448921a2f59 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -246,7 +246,7 @@ static void task_fpsimd_load(void) * * Softirqs (and preemption) must be disabled. */ -void fpsimd_save(void) +static void fpsimd_save(void) { struct fpsimd_last_state_struct const *last = this_cpu_ptr(&fpsimd_last_state); @@ -1122,12 +1122,22 @@ void fpsimd_flush_task_state(struct task_struct *t) * Invalidate any task's FPSIMD state that is present on this cpu. * This function must be called with softirqs disabled. */ -void fpsimd_flush_cpu_state(void) +static void fpsimd_flush_cpu_state(void) { __this_cpu_write(fpsimd_last_state.st, NULL); set_thread_flag(TIF_FOREIGN_FPSTATE); } +/* + * Save the FPSIMD state to memory and invalidate cpu view. + * This function must be called with softirqs (and preemption) disabled. + */ +void fpsimd_save_and_flush_cpu_state(void) +{ + fpsimd_save(); + fpsimd_flush_cpu_state(); +} + #ifdef CONFIG_KERNEL_MODE_NEON DEFINE_PER_CPU(bool, kernel_neon_busy); @@ -1284,8 +1294,7 @@ static int fpsimd_cpu_pm_notifier(struct notifier_block *self, { switch (cmd) { case CPU_PM_ENTER: - fpsimd_save(); - fpsimd_flush_cpu_state(); + fpsimd_save_and_flush_cpu_state(); break; case CPU_PM_EXIT: break; diff --git a/arch/arm64/kvm/fpsimd.c b/arch/arm64/kvm/fpsimd.c index 6e3c9c8b2df9..525010504f9d 100644 --- a/arch/arm64/kvm/fpsimd.c +++ b/arch/arm64/kvm/fpsimd.c @@ -112,9 +112,7 @@ void kvm_arch_vcpu_put_fp(struct kvm_vcpu *vcpu) if (vcpu->arch.flags & KVM_ARM64_FP_ENABLED) { u64 *guest_zcr = &vcpu->arch.ctxt.sys_regs[ZCR_EL1]; - /* Clean guest FP state to memory and invalidate cpu view */ - fpsimd_save(); - fpsimd_flush_cpu_state(); + fpsimd_save_and_flush_cpu_state(); if (guest_has_sve) *guest_zcr = read_sysreg_s(SYS_ZCR_EL12); -- 2.11.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel