From patchwork Wed Jan 21 12:43:10 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Suzuki K Poulose X-Patchwork-Id: 5676761 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 [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 074B3C058D for ; Wed, 21 Jan 2015 12:47:12 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id EFC5A203B7 for ; Wed, 21 Jan 2015 12:47:10 +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 DC886202C8 for ; Wed, 21 Jan 2015 12:47:09 +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 1YDuer-0003Td-5x; Wed, 21 Jan 2015 12:45:17 +0000 Received: from service87.mimecast.com ([91.220.42.44]) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1YDudU-0001kr-Cs for linux-arm-kernel@lists.infradead.org; Wed, 21 Jan 2015 12:43:54 +0000 Received: from cam-owa2.Emea.Arm.com (fw-tnat.cambridge.arm.com [217.140.96.140]) by service87.mimecast.com; Wed, 21 Jan 2015 12:43:25 +0000 Received: from e106634-lin.cambridge.arm.com ([10.1.255.212]) by cam-owa2.Emea.Arm.com with Microsoft SMTPSVC(6.0.3790.3959); Wed, 21 Jan 2015 12:43:25 +0000 From: "Suzuki K. Poulose" To: linux-arm-kernel@lists.infradead.org Subject: [PATCH 2/3] arm64: Consolidate hotplug notifier for instruction emulation Date: Wed, 21 Jan 2015 12:43:10 +0000 Message-Id: <1421844191-9263-3-git-send-email-suzuki.poulose@arm.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1421844191-9263-2-git-send-email-suzuki.poulose@arm.com> References: <1421844191-9263-1-git-send-email-suzuki.poulose@arm.com> <1421844191-9263-2-git-send-email-suzuki.poulose@arm.com> X-OriginalArrivalTime: 21 Jan 2015 12:43:25.0128 (UTC) FILETIME=[D8F85C80:01D03577] X-MC-Unique: 115012112432513901 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150121_044352_791864_A9E1238A X-CRM114-Status: GOOD ( 14.09 ) X-Spam-Score: -2.3 (--) Cc: Mark Rutland , yexl@marvell.com, "Suzuki K. Poulose" , Catalin Marinas , Punit Agrawal , Will Deacon , linux-kernel@vger.kernel.org, leo.yan@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=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, 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 From: "Suzuki K. Poulose" As of now each insn_emulation has a cpu hotplug notifier that enables/disables the CPU feature bit for the functionality. This patch re-arranges the code, such that there is only one notifier that runs through the list of registered emulation hooks and runs their corresponding set_hw_mode. We do nothing when a CPU is dying as we will set the appropriate bits as it comes back online based on the state of the hooks. Signed-off-by: Mark Rutland Signed-off-by: Suzuki K. Poulose Cc: Will Deacon Cc: Catalin Marinas Cc: Punit Agrawal --- arch/arm64/include/asm/cputype.h | 2 + arch/arm64/kernel/armv8_deprecated.c | 125 +++++++++++++++++++++------------- 2 files changed, 79 insertions(+), 48 deletions(-) diff --git a/arch/arm64/include/asm/cputype.h b/arch/arm64/include/asm/cputype.h index 44e578d..2c4c852 100644 --- a/arch/arm64/include/asm/cputype.h +++ b/arch/arm64/include/asm/cputype.h @@ -82,6 +82,8 @@ #define ID_AA64MMFR0_BIGEND(mmfr0) \ (((mmfr0) & ID_AA64MMFR0_BIGEND_MASK) >> ID_AA64MMFR0_BIGEND_SHIFT) +#define SCTLR_EL1_CP15BEN (0x1 << 5) + #ifndef __ASSEMBLY__ /* diff --git a/arch/arm64/kernel/armv8_deprecated.c b/arch/arm64/kernel/armv8_deprecated.c index c363671..2c991f1 100644 --- a/arch/arm64/kernel/armv8_deprecated.c +++ b/arch/arm64/kernel/armv8_deprecated.c @@ -19,6 +19,7 @@ #include #include #include +#include #define CREATE_TRACE_POINTS #include "trace-events-emulation.h" @@ -85,6 +86,57 @@ static void remove_emulation_hooks(struct insn_emulation_ops *ops) pr_notice("Removed %s emulation handler\n", ops->name); } +static void enable_insn_hw_mode(void *data) +{ + struct insn_emulation *insn = (struct insn_emulation *)data; + if (insn && insn->ops->set_hw_mode) + insn->ops->set_hw_mode(true); +} + +static void disable_insn_hw_mode(void *data) +{ + struct insn_emulation *insn = (struct insn_emulation *)data; + if (insn && insn->ops->set_hw_mode) + insn->ops->set_hw_mode(false); +} + +/* Run set_hw_mode(mode) on all active CPUs */ +static int run_all_cpu_set_hw_mode(struct insn_emulation *insn, bool enable) +{ + if (!insn->ops->set_hw_mode) + return -EINVAL; + if (enable) + on_each_cpu(enable_insn_hw_mode, (void *)insn, true); + else + on_each_cpu(disable_insn_hw_mode, (void *)insn, true); + return 0; +} + +/* + * Run set_hw_mode for all insns on a starting CPU. + * Returns: + * 0 - If all the hooks ran successfully. + * -EINVAL - At least one hook is not supported by the CPU. + */ +static int run_all_insn_set_hw_mode(unsigned long cpu) +{ + int rc = 0; + unsigned long flags; + struct insn_emulation *insn; + + raw_spin_lock_irqsave(&insn_emulation_lock, flags); + list_for_each_entry(insn, &insn_emulation, node) { + bool enable = (insn->current_mode == INSN_HW); + if (insn->ops->set_hw_mode && insn->ops->set_hw_mode(enable)) { + pr_warn(enable, "CPU[%ld] cannot support the emulation of %s", + cpu, insn->ops->name); + rc = -EINVAL; + } + } + raw_spin_unlock_irqrestore(&insn_emulation_lock, flags); + return rc; +} + static int update_insn_emulation_mode(struct insn_emulation *insn, enum insn_emulation_mode prev) { @@ -97,10 +149,8 @@ static int update_insn_emulation_mode(struct insn_emulation *insn, remove_emulation_hooks(insn->ops); break; case INSN_HW: - if (insn->ops->set_hw_mode) { - insn->ops->set_hw_mode(false); + if (!run_all_cpu_set_hw_mode(insn, false)) pr_notice("Disabled %s support\n", insn->ops->name); - } break; } @@ -111,10 +161,9 @@ static int update_insn_emulation_mode(struct insn_emulation *insn, register_emulation_hooks(insn->ops); break; case INSN_HW: - if (insn->ops->set_hw_mode && insn->ops->set_hw_mode(true)) + ret = run_all_cpu_set_hw_mode(insn, true); + if (!ret) pr_notice("Enabled %s support\n", insn->ops->name); - else - ret = -EINVAL; break; } @@ -133,6 +182,8 @@ static void register_insn_emulation(struct insn_emulation_ops *ops) switch (ops->status) { case INSN_DEPRECATED: insn->current_mode = INSN_EMULATE; + /* Disable the HW mode if it was turned on at early boot time */ + run_all_cpu_set_hw_mode(insn, false); insn->max = INSN_HW; break; case INSN_OBSOLETE: @@ -453,8 +504,6 @@ ret: return 0; } -#define SCTLR_EL1_CP15BEN (1 << 5) - static inline void config_sctlr_el1(u32 clear, u32 set) { u32 val; @@ -465,48 +514,13 @@ static inline void config_sctlr_el1(u32 clear, u32 set) asm volatile("msr sctlr_el1, %0" : : "r" (val)); } -static void enable_cp15_ben(void *info) -{ - config_sctlr_el1(0, SCTLR_EL1_CP15BEN); -} - -static void disable_cp15_ben(void *info) -{ - config_sctlr_el1(SCTLR_EL1_CP15BEN, 0); -} - -static int cpu_hotplug_notify(struct notifier_block *b, - unsigned long action, void *hcpu) -{ - switch (action) { - case CPU_STARTING: - case CPU_STARTING_FROZEN: - enable_cp15_ben(NULL); - return NOTIFY_DONE; - case CPU_DYING: - case CPU_DYING_FROZEN: - disable_cp15_ben(NULL); - return NOTIFY_DONE; - } - - return NOTIFY_OK; -} - -static struct notifier_block cpu_hotplug_notifier = { - .notifier_call = cpu_hotplug_notify, -}; - static int cp15_barrier_set_hw_mode(bool enable) { - if (enable) { - register_cpu_notifier(&cpu_hotplug_notifier); - on_each_cpu(enable_cp15_ben, NULL, true); - } else { - unregister_cpu_notifier(&cpu_hotplug_notifier); - on_each_cpu(disable_cp15_ben, NULL, true); - } - - return true; + if (enable) + config_sctlr_el1(0, SCTLR_EL1_CP15BEN); + else + config_sctlr_el1(SCTLR_EL1_CP15BEN, 0); + return 0; } static struct undef_hook cp15_barrier_hooks[] = { @@ -534,6 +548,20 @@ static struct insn_emulation_ops cp15_barrier_ops = { .set_hw_mode = cp15_barrier_set_hw_mode, }; +static int insn_cpu_hotplug_notify(struct notifier_block *b, + unsigned long action, void *hcpu) +{ + int rc = 0; + if ((action & ~CPU_TASKS_FROZEN) == CPU_STARTING) + rc = run_all_insn_set_hw_mode((unsigned long)hcpu); + + return notifier_from_errno(rc); +} + +static struct notifier_block insn_cpu_hotplug_notifier = { + .notifier_call = insn_cpu_hotplug_notify, +}; + /* * Invoked as late_initcall, since not needed before init spawned. */ @@ -545,6 +573,7 @@ static int __init armv8_deprecated_init(void) if (IS_ENABLED(CONFIG_CP15_BARRIER_EMULATION)) register_insn_emulation(&cp15_barrier_ops); + register_cpu_notifier(&insn_cpu_hotplug_notifier); register_insn_emulation_sysctl(ctl_abi); return 0;