From patchwork Thu Nov 17 18:35:41 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sebastian Andrzej Siewior X-Patchwork-Id: 696286 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3tKVKx13MNz9s65 for ; Fri, 18 Nov 2016 05:40:05 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755079AbcKQSgg (ORCPT ); Thu, 17 Nov 2016 13:36:36 -0500 Received: from Galois.linutronix.de ([146.0.238.70]:49708 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755044AbcKQSgf (ORCPT ); Thu, 17 Nov 2016 13:36:35 -0500 Received: from localhost ([127.0.0.1] helo=bazinga.breakpoint.cc) by Galois.linutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1c7RVh-0005qn-7V; Thu, 17 Nov 2016 19:34:09 +0100 From: Sebastian Andrzej Siewior To: linux-kernel@vger.kernel.org Cc: rt@linuxtronix.de, Sebastian Andrzej Siewior , Bjorn Helgaas , x86@kernel.org, linux-pci@vger.kernel.org Subject: [PATCH 20/20] x86/pci/amd-bus: Convert to hotplug state machine Date: Thu, 17 Nov 2016 19:35:41 +0100 Message-Id: <20161117183541.8588-21-bigeasy@linutronix.de> X-Mailer: git-send-email 2.10.2 In-Reply-To: <20161117183541.8588-1-bigeasy@linutronix.de> References: <20161117183541.8588-1-bigeasy@linutronix.de> MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Install the callbacks via the state machine and let the core invoke the callbacks on the already online CPUs. The smp_call_function_single() is dropped because the ONLINE callback is invoked on the target CPU since commit 1cf4f629d9d2 ("cpu/hotplug: Move online calls to hotplugged cpu"). smp_call_function_single() invokes the invoked function with interrupts disabled, but this calling convention is not preserved as the MSR is not modified by anything else than this code. Cc: Bjorn Helgaas Cc: x86@kernel.org Cc: linux-pci@vger.kernel.org Signed-off-by: Sebastian Andrzej Siewior --- arch/x86/pci/amd_bus.c | 34 +++++++--------------------------- 1 file changed, 7 insertions(+), 27 deletions(-) diff --git a/arch/x86/pci/amd_bus.c b/arch/x86/pci/amd_bus.c index c20d2cc7ef64..ae387e5ee6f7 100644 --- a/arch/x86/pci/amd_bus.c +++ b/arch/x86/pci/amd_bus.c @@ -327,35 +327,18 @@ static int __init early_root_info_init(void) #define ENABLE_CF8_EXT_CFG (1ULL << 46) -static void enable_pci_io_ecs(void *unused) +static int amd_bus_cpu_online(unsigned int cpu) { u64 reg; + rdmsrl(MSR_AMD64_NB_CFG, reg); if (!(reg & ENABLE_CF8_EXT_CFG)) { reg |= ENABLE_CF8_EXT_CFG; wrmsrl(MSR_AMD64_NB_CFG, reg); } + return 0; } -static int amd_cpu_notify(struct notifier_block *self, unsigned long action, - void *hcpu) -{ - int cpu = (long)hcpu; - switch (action) { - case CPU_ONLINE: - case CPU_ONLINE_FROZEN: - smp_call_function_single(cpu, enable_pci_io_ecs, NULL, 0); - break; - default: - break; - } - return NOTIFY_OK; -} - -static struct notifier_block amd_cpu_notifier = { - .notifier_call = amd_cpu_notify, -}; - static void __init pci_enable_pci_io_ecs(void) { #ifdef CONFIG_AMD_NB @@ -385,7 +368,7 @@ static void __init pci_enable_pci_io_ecs(void) static int __init pci_io_ecs_init(void) { - int cpu; + int ret; /* assume all cpus from fam10h have IO ECS */ if (boot_cpu_data.x86 < 0x10) @@ -395,12 +378,9 @@ static int __init pci_io_ecs_init(void) if (early_pci_allowed()) pci_enable_pci_io_ecs(); - cpu_notifier_register_begin(); - for_each_online_cpu(cpu) - amd_cpu_notify(&amd_cpu_notifier, (unsigned long)CPU_ONLINE, - (void *)(long)cpu); - __register_cpu_notifier(&amd_cpu_notifier); - cpu_notifier_register_done(); + ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "pci/amd_bus:online", + amd_bus_cpu_online, NULL); + WARN_ON(ret < 0); pci_probe |= PCI_HAS_IO_ECS;