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Sun, 17 Mar 2019 19:06:17 +0000 From: Michael Kelley To: "will.deacon@arm.com" , "marc.zyngier@arm.com" , "linux-arm-kernel@lists.infradead.org" , "gregkh@linuxfoundation.org" , "linux-kernel@vger.kernel.org" , "linux-hyperv@vger.kernel.org" , "olaf@aepfle.de" , "apw@canonical.com" , vkuznets , "jasowang@redhat.com" , "marcelo.cerri@canonical.com" , Sunil Muthuswamy , KY Srinivasan Subject: [PATCH v2 1/2] Drivers: hv: Create Hyper-V clocksource driver from existing clockevents code Thread-Topic: [PATCH v2 1/2] Drivers: hv: Create Hyper-V clocksource driver from existing clockevents code Thread-Index: AQHU3PR/1ks0xJJOT0qx5+YJAoKM+Q== Date: Sun, 17 Mar 2019 19:06:16 +0000 Message-ID: <1552849512-10063-2-git-send-email-mikelley@microsoft.com> References: <1552849512-10063-1-git-send-email-mikelley@microsoft.com> In-Reply-To: <1552849512-10063-1-git-send-email-mikelley@microsoft.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-clientproxiedby: CO2PR18CA0050.namprd18.prod.outlook.com (2603:10b6:104:2::18) To BN6PR21MB0466.namprd21.prod.outlook.com (2603:10b6:404:b2::16) x-ms-exchange-messagesentrepresentingtype: 1 x-mailer: git-send-email 1.8.3.1 x-originating-ip: [167.220.2.136] x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: bf01f286-392f-4936-a3d3-08d6ab0ba1c6 x-ms-office365-filtering-ht: Tenant x-microsoft-antispam: BCL:0; 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DIR:OUT; SFP:1102; SCL:1; SRVR:BN6PR21MB0788; H:BN6PR21MB0466.namprd21.prod.outlook.com; FPR:; SPF:None; LANG:en; PTR:InfoNoRecords; MX:1; A:1; received-spf: None (protection.outlook.com: microsoft.com does not designate permitted sender hosts) authentication-results: spf=none (sender IP is ) smtp.mailfrom=mikelley@microsoft.com; x-ms-exchange-senderadcheck: 1 x-microsoft-antispam-message-info: gccGkRwg3UHQx32glXNjX2sG8bIQz71t4+ow8p8pODdOYund/r4O6H3yHLYFWqVpopnSynxUzHldhMqBFRosKztEdqA6Ud4PwZZpI5FRc1hC5oSpm6qMrmS9hxbUj08wZM9jUwdi7TRM+wGbqqgrEh1y/7o+FHaDKZT+Vpru/JbBF023K2pDmHVkwVV94FSWmsc8qxx21hygRwmtapMAdLgI3r/DpkERPzd/b07KGye/DaQdxiGGOfS8gqD3G6nkZk9frdsmM3b4ZJXNxIjhmW393SQWRZXaR2m02ymEp9W3KviNwaK0/S2ekG9N+ClE1fAf/1N57ctnOo0iCKVKGKdpj9eNLbsCHxI9PcXGHe+vt76nYFwqr6oGS7iISBdU42s9RVFDgZgWVXRkyd+gnZetJSkUW2IJFXJ+mLwFYQY= MIME-Version: 1.0 X-OriginatorOrg: microsoft.com X-MS-Exchange-CrossTenant-Network-Message-Id: bf01f286-392f-4936-a3d3-08d6ab0ba1c6 X-MS-Exchange-CrossTenant-originalarrivaltime: 17 Mar 2019 19:06:16.9566 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 72f988bf-86f1-41af-91ab-2d7cd011db47 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN6PR21MB0788 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190317_120621_205423_CD2907BC X-CRM114-Status: GOOD ( 20.00 ) 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: "mark.rutland@arm.com" , "catalin.marinas@arm.com" , Michael Kelley Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP Clockevents code for Hyper-V synthetic timers is currently mixed in with other Hyper-V code. Move the code to a Hyper-V specific driver in the "clocksource" directory. Update the VMbus driver to call initialization and cleanup routines since the Hyper-V synthetic timers are not independently enumerated in ACPI. No behavior is changed and no new functionality is added. Suggested-by: Marc Zyngier Signed-off-by: Michael Kelley --- MAINTAINERS | 2 + arch/x86/include/asm/hyperv-tlfs.h | 6 ++ arch/x86/kernel/cpu/mshyperv.c | 2 + drivers/clocksource/Makefile | 1 + drivers/clocksource/hyperv_timer.c | 206 +++++++++++++++++++++++++++++++++++++ drivers/hv/Kconfig | 3 + drivers/hv/hv.c | 154 --------------------------- drivers/hv/hyperv_vmbus.h | 3 - drivers/hv/vmbus_drv.c | 39 +++---- include/clocksource/hyperv_timer.h | 26 +++++ 10 files changed, 266 insertions(+), 176 deletions(-) create mode 100644 drivers/clocksource/hyperv_timer.c create mode 100644 include/clocksource/hyperv_timer.h diff --git a/MAINTAINERS b/MAINTAINERS index 21ab064..63142da 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7159,6 +7159,7 @@ F: arch/x86/include/asm/trace/hyperv.h F: arch/x86/include/asm/hyperv-tlfs.h F: arch/x86/kernel/cpu/mshyperv.c F: arch/x86/hyperv +F: drivers/clocksource/hyperv_timer.c F: drivers/hid/hid-hyperv.c F: drivers/hv/ F: drivers/input/serio/hyperv-keyboard.c @@ -7168,6 +7169,7 @@ F: drivers/scsi/storvsc_drv.c F: drivers/uio/uio_hv_generic.c F: drivers/video/fbdev/hyperv_fb.c F: net/vmw_vsock/hyperv_transport.c +F: include/clocksource/hyperv_timer.h F: include/linux/hyperv.h F: include/uapi/linux/hyperv.h F: tools/hv/ diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h index 2bdbbbc..ee62f57 100644 --- a/arch/x86/include/asm/hyperv-tlfs.h +++ b/arch/x86/include/asm/hyperv-tlfs.h @@ -401,6 +401,12 @@ enum HV_GENERIC_SET_FORMAT { #define HV_STATUS_INVALID_CONNECTION_ID 18 #define HV_STATUS_INSUFFICIENT_BUFFERS 19 +/* + * The Hyper-V TimeRefCount register and the TSC + * page provide a guest VM clock with 100ns tick rate + */ +#define HV_CLOCK_HZ (NSEC_PER_SEC/100) + typedef struct _HV_REFERENCE_TSC_PAGE { __u32 tsc_sequence; __u32 res1; diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c index e81a2db..f53a35a 100644 --- a/arch/x86/kernel/cpu/mshyperv.c +++ b/arch/x86/kernel/cpu/mshyperv.c @@ -21,6 +21,7 @@ #include #include #include +#include #include #include #include @@ -84,6 +85,7 @@ __visible void __irq_entry hv_stimer0_vector_handler(struct pt_regs *regs) inc_irq_stat(hyperv_stimer0_count); if (hv_stimer0_handler) hv_stimer0_handler(); + add_interrupt_randomness(HYPERV_STIMER0_VECTOR, 0); ack_APIC_irq(); exiting_irq(); diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index be6e0fb..cd284a4 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -83,3 +83,4 @@ obj-$(CONFIG_ATCPIT100_TIMER) += timer-atcpit100.o obj-$(CONFIG_RISCV_TIMER) += timer-riscv.o obj-$(CONFIG_CSKY_MP_TIMER) += timer-mp-csky.o obj-$(CONFIG_GX6605S_TIMER) += timer-gx6605s.o +obj-$(CONFIG_HYPERV_TIMER) += hyperv_timer.o diff --git a/drivers/clocksource/hyperv_timer.c b/drivers/clocksource/hyperv_timer.c new file mode 100644 index 0000000..e856529 --- /dev/null +++ b/drivers/clocksource/hyperv_timer.c @@ -0,0 +1,206 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Clocksource driver for the synthetic counter and timers + * provided by the Hyper-V hypervisor to guest VMs, as described + * in the Hyper-V Top Level Functional Spec (TLFS). This driver + * is instruction set architecture independent. + * + * Copyright (C) 2019, Microsoft, Inc. + * + * Author: Michael Kelley + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +static struct clock_event_device __percpu *hv_clock_event; + +/* + * If false, we're using the old mechanism for stimer0 interrupts + * where it sends a VMbus message when it expires. The old + * mechanism is used when running on older versions of Hyper-V + * that don't support Direct Mode. While Hyper-V provides + * four stimer's per CPU, Linux uses only stimer0. + */ +static bool direct_mode_enabled; + +static int stimer0_irq; +static int stimer0_vector; +static int stimer0_message_sint; +static int stimer0_cpuhp_online; + +/* + * ISR for when stimer0 is operating in Direct Mode. Direct Mode + * does not use VMbus or any VMbus messages, so process here and not + * in the VMbus driver code. + */ +void hv_stimer0_isr(void) +{ + struct clock_event_device *ce; + + ce = this_cpu_ptr(hv_clock_event); + ce->event_handler(ce); +} +EXPORT_SYMBOL_GPL(hv_stimer0_isr); + +static int hv_ce_set_next_event(unsigned long delta, + struct clock_event_device *evt) +{ + u64 current_tick; + + WARN_ON(!clockevent_state_oneshot(evt)); + + current_tick = hyperv_cs->read(NULL); + current_tick += delta; + hv_init_timer(0, current_tick); + return 0; +} + +static int hv_ce_shutdown(struct clock_event_device *evt) +{ + hv_init_timer(0, 0); + hv_init_timer_config(0, 0); + if (direct_mode_enabled) + hv_disable_stimer0_percpu_irq(stimer0_irq); + + return 0; +} + +static int hv_ce_set_oneshot(struct clock_event_device *evt) +{ + union hv_stimer_config timer_cfg; + + timer_cfg.as_uint64 = 0; + timer_cfg.enable = 1; + timer_cfg.auto_enable = 1; + if (direct_mode_enabled) { + /* + * When it expires, the timer will directly interrupt + * on the specified hardware vector/IRQ. + */ + timer_cfg.direct_mode = 1; + timer_cfg.apic_vector = stimer0_vector; + hv_enable_stimer0_percpu_irq(stimer0_irq); + } else { + /* + * When it expires, the timer will generate a VMbus message, + * to be handled by the normal VMbus interrupt handler. + */ + timer_cfg.direct_mode = 0; + timer_cfg.sintx = stimer0_message_sint; + } + hv_init_timer_config(0, timer_cfg.as_uint64); + return 0; +} + +/* + * hv_stimer_init - Per-cpu initialization of the clockevent + */ +static int hv_stimer_init(unsigned int cpu) +{ + struct clock_event_device *ce; + + if (ms_hyperv.features & HV_MSR_SYNTIMER_AVAILABLE) { + ce = per_cpu_ptr(hv_clock_event, cpu); + ce->name = "Hyper-V clockevent"; + ce->features = CLOCK_EVT_FEAT_ONESHOT; + ce->cpumask = cpumask_of(cpu); + ce->rating = 1000; + ce->set_state_shutdown = hv_ce_shutdown; + ce->set_state_oneshot = hv_ce_set_oneshot; + ce->set_next_event = hv_ce_set_next_event; + + clockevents_config_and_register(ce, + HV_CLOCK_HZ, + HV_MIN_DELTA_TICKS, + HV_MAX_MAX_DELTA_TICKS); + } + return 0; +} + +/* + * hv_stimer_cleanup - Per-cpu cleanup of the clockevent + */ +int hv_stimer_cleanup(unsigned int cpu) +{ + struct clock_event_device *ce; + + /* Turn off clockevent device */ + if (ms_hyperv.features & HV_MSR_SYNTIMER_AVAILABLE) { + ce = per_cpu_ptr(hv_clock_event, cpu); + clockevents_unbind_device(ce, cpu); + hv_ce_shutdown(ce); + } + + return 0; +} +EXPORT_SYMBOL_GPL(hv_stimer_cleanup); + +/* hv_stimer_alloc - Global initialization of the clockevent and stimer0 */ +int hv_stimer_alloc(int sint) +{ + int ret; + + hv_clock_event = alloc_percpu(struct clock_event_device); + if (!hv_clock_event) + return -ENOMEM; + + direct_mode_enabled = ms_hyperv.misc_features & + HV_STIMER_DIRECT_MODE_AVAILABLE; + if (direct_mode_enabled && + hv_setup_stimer0_irq(&stimer0_irq, &stimer0_vector, + hv_stimer0_isr)) + goto err_irq; + + stimer0_message_sint = sint; + + ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "hyperv/stimer0:online", + hv_stimer_init, hv_stimer_cleanup); + if (ret < 0) + goto err_cpuhp; + stimer0_cpuhp_online = ret; + return 0; + +err_cpuhp: + if (direct_mode_enabled) + hv_remove_stimer0_irq(stimer0_irq); +err_irq: + free_percpu(hv_clock_event); + return -EINVAL; +} +EXPORT_SYMBOL_GPL(hv_stimer_alloc); + +/* hv_stimer_free - Free global resources allocated by hv_stimer_alloc() */ +void hv_stimer_free(void) +{ + cpuhp_remove_state(stimer0_cpuhp_online); + if (direct_mode_enabled) + hv_remove_stimer0_irq(stimer0_irq); + free_percpu(hv_clock_event); +} +EXPORT_SYMBOL_GPL(hv_stimer_free); + +/* + * Do a global cleanup of clockevents for the cases of kexec and + * vmbus exit + */ +void hv_stimer_global_cleanup(void) +{ + int cpu; + struct clock_event_device *ce; + + if (ms_hyperv.features & HV_MSR_SYNTIMER_AVAILABLE) + for_each_present_cpu(cpu) { + ce = per_cpu_ptr(hv_clock_event, cpu); + clockevents_unbind_device(ce, cpu); + } + hv_stimer_free(); +} +EXPORT_SYMBOL_GPL(hv_stimer_global_cleanup); diff --git a/drivers/hv/Kconfig b/drivers/hv/Kconfig index 1c1a251..c423e57 100644 --- a/drivers/hv/Kconfig +++ b/drivers/hv/Kconfig @@ -10,6 +10,9 @@ config HYPERV Select this option to run Linux as a Hyper-V client operating system. +config HYPERV_TIMER + def_bool HYPERV + config HYPERV_TSCPAGE def_bool HYPERV && X86_64 diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c index 632d256..e3ee010 100644 --- a/drivers/hv/hv.c +++ b/drivers/hv/hv.c @@ -36,21 +36,6 @@ struct hv_context hv_context; /* - * If false, we're using the old mechanism for stimer0 interrupts - * where it sends a VMbus message when it expires. The old - * mechanism is used when running on older versions of Hyper-V - * that don't support Direct Mode. While Hyper-V provides - * four stimer's per CPU, Linux uses only stimer0. - */ -static bool direct_mode_enabled; -static int stimer0_irq; -static int stimer0_vector; - -#define HV_TIMER_FREQUENCY (10 * 1000 * 1000) /* 100ns period */ -#define HV_MAX_MAX_DELTA_TICKS 0xffffffff -#define HV_MIN_DELTA_TICKS 1 - -/* * hv_init - Main initialization routine. * * This routine must be called before any other routines in here are called @@ -60,9 +45,6 @@ int hv_init(void) hv_context.cpu_context = alloc_percpu(struct hv_per_cpu_context); if (!hv_context.cpu_context) return -ENOMEM; - - direct_mode_enabled = ms_hyperv.misc_features & - HV_STIMER_DIRECT_MODE_AVAILABLE; return 0; } @@ -101,89 +83,6 @@ int hv_post_message(union hv_connection_id connection_id, return status & 0xFFFF; } -/* - * ISR for when stimer0 is operating in Direct Mode. Direct Mode - * does not use VMbus or any VMbus messages, so process here and not - * in the VMbus driver code. - */ - -static void hv_stimer0_isr(void) -{ - struct hv_per_cpu_context *hv_cpu; - - hv_cpu = this_cpu_ptr(hv_context.cpu_context); - hv_cpu->clk_evt->event_handler(hv_cpu->clk_evt); - add_interrupt_randomness(stimer0_vector, 0); -} - -static int hv_ce_set_next_event(unsigned long delta, - struct clock_event_device *evt) -{ - u64 current_tick; - - WARN_ON(!clockevent_state_oneshot(evt)); - - current_tick = hyperv_cs->read(NULL); - current_tick += delta; - hv_init_timer(0, current_tick); - return 0; -} - -static int hv_ce_shutdown(struct clock_event_device *evt) -{ - hv_init_timer(0, 0); - hv_init_timer_config(0, 0); - if (direct_mode_enabled) - hv_disable_stimer0_percpu_irq(stimer0_irq); - - return 0; -} - -static int hv_ce_set_oneshot(struct clock_event_device *evt) -{ - union hv_stimer_config timer_cfg; - - timer_cfg.as_uint64 = 0; - timer_cfg.enable = 1; - timer_cfg.auto_enable = 1; - if (direct_mode_enabled) { - /* - * When it expires, the timer will directly interrupt - * on the specified hardware vector/IRQ. - */ - timer_cfg.direct_mode = 1; - timer_cfg.apic_vector = stimer0_vector; - hv_enable_stimer0_percpu_irq(stimer0_irq); - } else { - /* - * When it expires, the timer will generate a VMbus message, - * to be handled by the normal VMbus interrupt handler. - */ - timer_cfg.direct_mode = 0; - timer_cfg.sintx = VMBUS_MESSAGE_SINT; - } - hv_init_timer_config(0, timer_cfg.as_uint64); - return 0; -} - -static void hv_init_clockevent_device(struct clock_event_device *dev, int cpu) -{ - dev->name = "Hyper-V clockevent"; - dev->features = CLOCK_EVT_FEAT_ONESHOT; - dev->cpumask = cpumask_of(cpu); - dev->rating = 1000; - /* - * Avoid settint dev->owner = THIS_MODULE deliberately as doing so will - * result in clockevents_config_and_register() taking additional - * references to the hv_vmbus module making it impossible to unload. - */ - - dev->set_state_shutdown = hv_ce_shutdown; - dev->set_state_oneshot = hv_ce_set_oneshot; - dev->set_next_event = hv_ce_set_next_event; -} - - int hv_synic_alloc(void) { int cpu; @@ -212,14 +111,6 @@ int hv_synic_alloc(void) tasklet_init(&hv_cpu->msg_dpc, vmbus_on_msg_dpc, (unsigned long) hv_cpu); - hv_cpu->clk_evt = kzalloc(sizeof(struct clock_event_device), - GFP_KERNEL); - if (hv_cpu->clk_evt == NULL) { - pr_err("Unable to allocate clock event device\n"); - goto err; - } - hv_init_clockevent_device(hv_cpu->clk_evt, cpu); - hv_cpu->synic_message_page = (void *)get_zeroed_page(GFP_ATOMIC); if (hv_cpu->synic_message_page == NULL) { @@ -242,11 +133,6 @@ int hv_synic_alloc(void) INIT_LIST_HEAD(&hv_cpu->chan_list); } - if (direct_mode_enabled && - hv_setup_stimer0_irq(&stimer0_irq, &stimer0_vector, - hv_stimer0_isr)) - goto err; - return 0; err: /* @@ -265,7 +151,6 @@ void hv_synic_free(void) struct hv_per_cpu_context *hv_cpu = per_cpu_ptr(hv_context.cpu_context, cpu); - kfree(hv_cpu->clk_evt); free_page((unsigned long)hv_cpu->synic_event_page); free_page((unsigned long)hv_cpu->synic_message_page); free_page((unsigned long)hv_cpu->post_msg_page); @@ -324,39 +209,10 @@ int hv_synic_init(unsigned int cpu) hv_set_synic_state(sctrl.as_uint64); - /* - * Register the per-cpu clockevent source. - */ - if (ms_hyperv.features & HV_MSR_SYNTIMER_AVAILABLE) - clockevents_config_and_register(hv_cpu->clk_evt, - HV_TIMER_FREQUENCY, - HV_MIN_DELTA_TICKS, - HV_MAX_MAX_DELTA_TICKS); return 0; } /* - * hv_synic_clockevents_cleanup - Cleanup clockevent devices - */ -void hv_synic_clockevents_cleanup(void) -{ - int cpu; - - if (!(ms_hyperv.features & HV_MSR_SYNTIMER_AVAILABLE)) - return; - - if (direct_mode_enabled) - hv_remove_stimer0_irq(stimer0_irq); - - for_each_present_cpu(cpu) { - struct hv_per_cpu_context *hv_cpu - = per_cpu_ptr(hv_context.cpu_context, cpu); - - clockevents_unbind_device(hv_cpu->clk_evt, cpu); - } -} - -/* * hv_synic_cleanup - Cleanup routine for hv_synic_init(). */ int hv_synic_cleanup(unsigned int cpu) @@ -401,16 +257,6 @@ int hv_synic_cleanup(unsigned int cpu) if (channel_found && vmbus_connection.conn_state == CONNECTED) return -EBUSY; - /* Turn off clockevent device */ - if (ms_hyperv.features & HV_MSR_SYNTIMER_AVAILABLE) { - struct hv_per_cpu_context *hv_cpu - = this_cpu_ptr(hv_context.cpu_context); - - clockevents_unbind_device(hv_cpu->clk_evt, cpu); - hv_ce_shutdown(hv_cpu->clk_evt); - put_cpu_ptr(hv_cpu); - } - hv_get_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64); shared_sint.masked = 1; diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h index cb86b133..ffd4ad8 100644 --- a/drivers/hv/hyperv_vmbus.h +++ b/drivers/hv/hyperv_vmbus.h @@ -151,7 +151,6 @@ struct hv_per_cpu_context { * per-cpu list of the channels based on their CPU affinity. */ struct list_head chan_list; - struct clock_event_device *clk_evt; }; struct hv_context { @@ -189,8 +188,6 @@ extern int hv_post_message(union hv_connection_id connection_id, extern int hv_synic_cleanup(unsigned int cpu); -extern void hv_synic_clockevents_cleanup(void); - /* Interface */ diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index 000b53e..e71b04b 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -43,6 +43,7 @@ #include #include #include +#include #include "hyperv_vmbus.h" struct vmbus_dynid { @@ -939,17 +940,6 @@ static void vmbus_onmessage_work(struct work_struct *work) kfree(ctx); } -static void hv_process_timer_expiration(struct hv_message *msg, - struct hv_per_cpu_context *hv_cpu) -{ - struct clock_event_device *dev = hv_cpu->clk_evt; - - if (dev->event_handler) - dev->event_handler(dev); - - vmbus_signal_eom(msg, HVMSG_TIMER_EXPIRED); -} - void vmbus_on_msg_dpc(unsigned long data) { struct hv_per_cpu_context *hv_cpu = (void *)data; @@ -1143,9 +1133,10 @@ static void vmbus_isr(void) /* Check if there are actual msgs to be processed */ if (msg->header.message_type != HVMSG_NONE) { - if (msg->header.message_type == HVMSG_TIMER_EXPIRED) - hv_process_timer_expiration(msg, hv_cpu); - else + if (msg->header.message_type == HVMSG_TIMER_EXPIRED) { + hv_stimer0_isr(); + vmbus_signal_eom(msg, HVMSG_TIMER_EXPIRED); + } else tasklet_schedule(&hv_cpu->msg_dpc); } @@ -1248,8 +1239,8 @@ static int vmbus_bus_init(void) if (ret) goto err_alloc; /* - * Initialize the per-cpu interrupt state and - * connect to the host. + * Initialize the per-cpu interrupt state and stimer state. + * Then connect to the host. */ ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "hyperv/vmbus:online", hv_synic_init, hv_synic_cleanup); @@ -1257,6 +1248,10 @@ static int vmbus_bus_init(void) goto err_alloc; hyperv_cpuhp_online = ret; + ret = hv_stimer_alloc(VMBUS_MESSAGE_SINT); + if (ret < 0) + goto err_stimer_alloc; + ret = vmbus_connect(); if (ret) goto err_connect; @@ -1301,6 +1296,8 @@ static int vmbus_bus_init(void) return 0; err_connect: + hv_stimer_free(); +err_stimer_alloc: cpuhp_remove_state(hyperv_cpuhp_online); err_alloc: hv_synic_free(); @@ -1971,7 +1968,7 @@ static int vmbus_acpi_add(struct acpi_device *device) static void hv_kexec_handler(void) { - hv_synic_clockevents_cleanup(); + hv_stimer_global_cleanup(); vmbus_initiate_unload(false); vmbus_connection.conn_state = DISCONNECTED; /* Make sure conn_state is set as hv_synic_cleanup checks for it */ @@ -1982,6 +1979,8 @@ static void hv_kexec_handler(void) static void hv_crash_handler(struct pt_regs *regs) { + int cpu; + vmbus_initiate_unload(true); /* * In crash handler we can't schedule synic cleanup for all CPUs, @@ -1989,7 +1988,9 @@ static void hv_crash_handler(struct pt_regs *regs) * for kdump. */ vmbus_connection.conn_state = DISCONNECTED; - hv_synic_cleanup(smp_processor_id()); + cpu = smp_processor_id(); + hv_stimer_cleanup(cpu); + hv_synic_cleanup(cpu); hyperv_cleanup(); }; @@ -2038,7 +2039,7 @@ static void __exit vmbus_exit(void) hv_remove_kexec_handler(); hv_remove_crash_handler(); vmbus_connection.conn_state = DISCONNECTED; - hv_synic_clockevents_cleanup(); + hv_stimer_global_cleanup(); vmbus_disconnect(); hv_remove_vmbus_irq(); for_each_online_cpu(cpu) { diff --git a/include/clocksource/hyperv_timer.h b/include/clocksource/hyperv_timer.h new file mode 100644 index 0000000..1a5698c --- /dev/null +++ b/include/clocksource/hyperv_timer.h @@ -0,0 +1,26 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* + * Definitions for the clocksource provided by the Hyper-V + * hypervisor to guest VMs, as described in the Hyper-V Top + * Level Functional Spec (TLFS). + * + * Copyright (C) 2019, Microsoft, Inc. + * + * Author: Michael Kelley + */ + +#ifndef __CLKSOURCE_HYPERV_TIMER_H +#define __CLKSOURCE_HYPERV_TIMER_H + +#define HV_MAX_MAX_DELTA_TICKS 0xffffffff +#define HV_MIN_DELTA_TICKS 1 + +/* Routines called by the VMbus driver */ +extern int hv_stimer_alloc(int sint); +extern void hv_stimer_free(void); +extern int hv_stimer_cleanup(unsigned int cpu); +extern void hv_stimer_global_cleanup(void); +extern void hv_stimer0_isr(void); + +#endif