From 929320e4b4c10708d3477d7e395f0ce7b0cc8744 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Sun, 23 Feb 2014 21:40:20 +0000 Subject: x86: Add proper vector accounting for HYPERVISOR_CALLBACK_VECTOR HyperV abuses a device interrupt to account for the HYPERVISOR_CALLBACK_VECTOR. Provide proper accounting as we have for the other vectors as well. Signed-off-by: Thomas Gleixner Cc: Peter Zijlstra Cc: Konrad Rzeszutek Wilk Cc: K. Y. Srinivasan Cc: x86 Link: http://lkml.kernel.org/r/20140223212738.681855582@linutronix.de Signed-off-by: Thomas Gleixner --- arch/x86/kernel/irq.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'arch/x86/kernel') diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c index d99f31d9a750..42805fac0092 100644 --- a/arch/x86/kernel/irq.c +++ b/arch/x86/kernel/irq.c @@ -124,6 +124,12 @@ int arch_show_interrupts(struct seq_file *p, int prec) for_each_online_cpu(j) seq_printf(p, "%10u ", per_cpu(mce_poll_count, j)); seq_printf(p, " Machine check polls\n"); +#endif +#if defined(CONFIG_HYPERV) || defined(CONFIG_XEN) + seq_printf(p, "%*s: ", prec, "THR"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->irq_hv_callback_count); + seq_printf(p, " Hypervisor callback interrupts\n"); #endif seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count)); #if defined(CONFIG_X86_IO_APIC) -- cgit v1.2.3 From 1aec169673d7db113c37367bbc371c2ba8109f06 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Sun, 23 Feb 2014 21:40:22 +0000 Subject: x86: Hyperv: Cleanup the irq mess The vmbus/hyperv interrupt handling is another complete trainwreck and probably the worst of all currently in tree. If CONFIG_HYPERV=y then the interrupt delivery to the vmbus happens via the direct HYPERVISOR_CALLBACK_VECTOR. So far so good, but: The driver requests first a normal device interrupt. The only reason to do so is to increment the interrupt stats of that device interrupt. For no reason it also installs a private flow handler. We have proper accounting mechanisms for direct vectors, but of course it's too much effort to add that 5 lines of code. Aside of that the alloc_intr_gate() is not protected against reallocation which makes module reload impossible. Solution to the problem is simple to rip out the whole mess and implement it correctly. First of all move all that code to arch/x86/kernel/cpu/mshyperv.c and merily install the HYPERVISOR_CALLBACK_VECTOR with proper reallocation protection and use the proper direct vector accounting mechanism. Signed-off-by: Thomas Gleixner Acked-by: K. Y. Srinivasan Cc: Peter Zijlstra Cc: Greg Kroah-Hartman Cc: linuxdrivers Cc: x86 Link: http://lkml.kernel.org/r/20140223212739.028307673@linutronix.de Signed-off-by: Thomas Gleixner --- arch/x86/include/asm/mshyperv.h | 4 ++- arch/x86/kernel/cpu/mshyperv.c | 78 +++++++++++++++++++++-------------------- drivers/hv/vmbus_drv.c | 39 +++------------------ 3 files changed, 47 insertions(+), 74 deletions(-) (limited to 'arch/x86/kernel') diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h index cd9c41938b8a..e98f66f35635 100644 --- a/arch/x86/include/asm/mshyperv.h +++ b/arch/x86/include/asm/mshyperv.h @@ -2,6 +2,7 @@ #define _ASM_X86_MSHYPER_H #include +#include #include struct ms_hyperv_info { @@ -16,6 +17,7 @@ void hyperv_callback_vector(void); #define trace_hyperv_callback_vector hyperv_callback_vector #endif void hyperv_vector_handler(struct pt_regs *regs); -void hv_register_vmbus_handler(int irq, irq_handler_t handler); +int hv_setup_vmbus_irq(int irq, irq_handler_t handler, void *dev_id); +void hv_remove_vmbus_irq(int irq, void *dev_id); #endif diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c index 9f7ca266864a..1bd316cd32c8 100644 --- a/arch/x86/kernel/cpu/mshyperv.c +++ b/arch/x86/kernel/cpu/mshyperv.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include #include @@ -30,6 +31,45 @@ struct ms_hyperv_info ms_hyperv; EXPORT_SYMBOL_GPL(ms_hyperv); +#ifdef CONFIG_HYPERV +static irq_handler_t *vmbus_handler; + +void hyperv_vector_handler(struct pt_regs *regs) +{ + struct pt_regs *old_regs = set_irq_regs(regs); + + irq_enter(); + exit_idle(); + + inc_irq_stat(irq_hv_callback_count); + if (vmbus_handler) + vmbus_handler(); + + irq_exit(); + set_irq_regs(old_regs); +} + +int hv_setup_vmbus_irq(int irq, irq_handler_t *handler, void *dev_id) +{ + vmbus_handler = handler; + /* + * Setup the IDT for hypervisor callback. Prevent reallocation + * at module reload. + */ + if (!test_bit(HYPERVISOR_CALLBACK_VECTOR, used_vectors)) + alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, + hyperv_callback_vector); +} + +void hv_remove_vmbus_irq(unsigned int irq, void *dev_id) +{ + /* We have no way to deallocate the interrupt gate */ + vmbus_handler = NULL; +} +EXPORT_SYMBOL_GPL(hv_setup_vmbus_irq); +EXPORT_SYMBOL_GPL(hv_remove_vmbus_irq); +#endif + static uint32_t __init ms_hyperv_platform(void) { u32 eax; @@ -113,41 +153,3 @@ const __refconst struct hypervisor_x86 x86_hyper_ms_hyperv = { .init_platform = ms_hyperv_init_platform, }; EXPORT_SYMBOL(x86_hyper_ms_hyperv); - -#if IS_ENABLED(CONFIG_HYPERV) -static int vmbus_irq = -1; -static irq_handler_t vmbus_isr; - -void hv_register_vmbus_handler(int irq, irq_handler_t handler) -{ - /* - * Setup the IDT for hypervisor callback. - */ - alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, hyperv_callback_vector); - - vmbus_irq = irq; - vmbus_isr = handler; -} - -void hyperv_vector_handler(struct pt_regs *regs) -{ - struct pt_regs *old_regs = set_irq_regs(regs); - struct irq_desc *desc; - - irq_enter(); - exit_idle(); - - desc = irq_to_desc(vmbus_irq); - - if (desc) - generic_handle_irq_desc(vmbus_irq, desc); - - irq_exit(); - set_irq_regs(old_regs); -} -#else -void hv_register_vmbus_handler(int irq, irq_handler_t handler) -{ -} -#endif -EXPORT_SYMBOL_GPL(hv_register_vmbus_handler); diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index 077bb1bdac34..5a6909fff1c1 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -25,7 +25,6 @@ #include #include #include -#include #include #include #include @@ -558,9 +557,6 @@ static struct bus_type hv_bus = { .dev_groups = vmbus_groups, }; -static const char *driver_name = "hyperv"; - - struct onmessage_work_context { struct work_struct work; struct hv_message msg; @@ -676,19 +672,6 @@ static irqreturn_t vmbus_isr(int irq, void *dev_id) return IRQ_NONE; } -/* - * vmbus interrupt flow handler: - * vmbus interrupts can concurrently occur on multiple CPUs and - * can be handled concurrently. - */ - -static void vmbus_flow_handler(unsigned int irq, struct irq_desc *desc) -{ - kstat_incr_irqs_this_cpu(irq, desc); - - desc->action->handler(irq, desc->action->dev_id); -} - /* * vmbus_bus_init -Main vmbus driver initialization routine. * @@ -715,26 +698,13 @@ static int vmbus_bus_init(int irq) if (ret) goto err_cleanup; - ret = request_irq(irq, vmbus_isr, 0, driver_name, hv_acpi_dev); + ret = hv_setup_vmbus_irq(irq, vmbus_isr, hv_acpi_dev); if (ret != 0) { - pr_err("Unable to request IRQ %d\n", - irq); + pr_err("Unable to request IRQ %d\n", irq); goto err_unregister; } - /* - * Vmbus interrupts can be handled concurrently on - * different CPUs. Establish an appropriate interrupt flow - * handler that can support this model. - */ - irq_set_handler(irq, vmbus_flow_handler); - - /* - * Register our interrupt handler. - */ - hv_register_vmbus_handler(irq, vmbus_isr); - ret = hv_synic_alloc(); if (ret) goto err_alloc; @@ -753,7 +723,7 @@ static int vmbus_bus_init(int irq) err_alloc: hv_synic_free(); - free_irq(irq, hv_acpi_dev); + hv_remove_vmbus_irq(irq, hv_acpi_dev); err_unregister: bus_unregister(&hv_bus); @@ -978,8 +948,7 @@ cleanup: static void __exit vmbus_exit(void) { - - free_irq(irq, hv_acpi_dev); + hv_remove_vmbus_irq(irq, hv_acpi_dev); vmbus_free_channels(); bus_unregister(&hv_bus); hv_cleanup(); -- cgit v1.2.3 From d20d2efbf227042920d386b8eda878815f63c987 Mon Sep 17 00:00:00 2001 From: Michael Opdenacker Date: Tue, 4 Mar 2014 21:35:05 +0100 Subject: x86: Remove deprecated IRQF_DISABLED This patch removes the IRQF_DISABLED flag from x86 architecture code. It's a NOOP since 2.6.35 and it will be removed one day. Signed-off-by: Michael Opdenacker Cc: venki@google.com Link: http://lkml.kernel.org/r/1393965305-17248-1-git-send-email-michael.opdenacker@free-electrons.com Signed-off-by: Thomas Gleixner --- arch/x86/include/asm/floppy.h | 4 ++-- arch/x86/kernel/hpet.c | 2 +- arch/x86/kernel/time.c | 2 +- 3 files changed, 4 insertions(+), 4 deletions(-) (limited to 'arch/x86/kernel') diff --git a/arch/x86/include/asm/floppy.h b/arch/x86/include/asm/floppy.h index d3d74698dce9..1c7eefe32502 100644 --- a/arch/x86/include/asm/floppy.h +++ b/arch/x86/include/asm/floppy.h @@ -145,10 +145,10 @@ static int fd_request_irq(void) { if (can_use_virtual_dma) return request_irq(FLOPPY_IRQ, floppy_hardint, - IRQF_DISABLED, "floppy", NULL); + 0, "floppy", NULL); else return request_irq(FLOPPY_IRQ, floppy_interrupt, - IRQF_DISABLED, "floppy", NULL); + 0, "floppy", NULL); } static unsigned long dma_mem_alloc(unsigned long size) diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c index da85a8e830a1..45d2ded7b1e2 100644 --- a/arch/x86/kernel/hpet.c +++ b/arch/x86/kernel/hpet.c @@ -521,7 +521,7 @@ static int hpet_setup_irq(struct hpet_dev *dev) { if (request_irq(dev->irq, hpet_interrupt_handler, - IRQF_TIMER | IRQF_DISABLED | IRQF_NOBALANCING, + IRQF_TIMER | IRQF_NOBALANCING, dev->name, dev)) return -1; diff --git a/arch/x86/kernel/time.c b/arch/x86/kernel/time.c index 24d3c91e9812..36b2cee629cb 100644 --- a/arch/x86/kernel/time.c +++ b/arch/x86/kernel/time.c @@ -62,7 +62,7 @@ static irqreturn_t timer_interrupt(int irq, void *dev_id) static struct irqaction irq0 = { .handler = timer_interrupt, - .flags = IRQF_DISABLED | IRQF_NOBALANCING | IRQF_IRQPOLL | IRQF_TIMER, + .flags = IRQF_NOBALANCING | IRQF_IRQPOLL | IRQF_TIMER, .name = "timer" }; -- cgit v1.2.3 From 3c433679ab666fb76a9399679819a303989e8ead Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Tue, 4 Mar 2014 23:39:58 +0100 Subject: x86: hyperv: Make it build with CONFIG_HYPERV=m again Commit 1aec16967 (x86: Hyperv: Cleanup the irq mess) removed the ability to build the hyperv stuff as a module. Bring it back. Reported-by: fengguang.wu@intel.com Signed-off-by: Thomas Gleixner Cc: K. Y. Srinivasan Cc: Peter Zijlstra Cc: Greg Kroah-Hartman Cc: linuxdrivers Cc: x86 --- arch/x86/kernel/cpu/mshyperv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86/kernel') diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c index 1bd316cd32c8..316e106e26f0 100644 --- a/arch/x86/kernel/cpu/mshyperv.c +++ b/arch/x86/kernel/cpu/mshyperv.c @@ -31,7 +31,7 @@ struct ms_hyperv_info ms_hyperv; EXPORT_SYMBOL_GPL(ms_hyperv); -#ifdef CONFIG_HYPERV +#if IS_ENABLED(CONFIG_HYPERV) static irq_handler_t *vmbus_handler; void hyperv_vector_handler(struct pt_regs *regs) -- cgit v1.2.3 From 13b5be56d1c5ed302df53f6dfbe19b9f4e3fd3ce Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Tue, 4 Mar 2014 23:51:34 +0100 Subject: x86: hyperv: Fix brown paperbag typos reported by Fenguangs build robot Reported-by: fengguang.wu@intel.com Signed-off-by: Thomas Gleixner Cc: K. Y. Srinivasan Cc: Peter Zijlstra Cc: Greg Kroah-Hartman Cc: linuxdrivers Cc: x86 --- arch/x86/kernel/cpu/mshyperv.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/x86/kernel') diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c index 316e106e26f0..a6f5f351f7af 100644 --- a/arch/x86/kernel/cpu/mshyperv.c +++ b/arch/x86/kernel/cpu/mshyperv.c @@ -32,7 +32,7 @@ struct ms_hyperv_info ms_hyperv; EXPORT_SYMBOL_GPL(ms_hyperv); #if IS_ENABLED(CONFIG_HYPERV) -static irq_handler_t *vmbus_handler; +static irq_handler_t vmbus_handler; void hyperv_vector_handler(struct pt_regs *regs) { @@ -49,7 +49,7 @@ void hyperv_vector_handler(struct pt_regs *regs) set_irq_regs(old_regs); } -int hv_setup_vmbus_irq(int irq, irq_handler_t *handler, void *dev_id) +int hv_setup_vmbus_irq(int irq, irq_handler_t handler, void *dev_id) { vmbus_handler = handler; /* @@ -61,7 +61,7 @@ int hv_setup_vmbus_irq(int irq, irq_handler_t *handler, void *dev_id) hyperv_callback_vector); } -void hv_remove_vmbus_irq(unsigned int irq, void *dev_id) +void hv_remove_vmbus_irq(int irq, void *dev_id) { /* We have no way to deallocate the interrupt gate */ vmbus_handler = NULL; -- cgit v1.2.3 From 76d388cd72ab08c2c56b1e2bd430e7422fc40168 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 5 Mar 2014 13:42:14 +0100 Subject: x86: hyperv: Fixup the (brain) damage caused by the irq cleanup Compiling last minute changes without setting the proper config options is not really clever. Reported-by: Fengguang Wu Signed-off-by: Thomas Gleixner --- arch/x86/include/asm/mshyperv.h | 4 ++-- arch/x86/kernel/cpu/mshyperv.c | 6 +++--- drivers/hv/vmbus_drv.c | 26 ++++++-------------------- 3 files changed, 11 insertions(+), 25 deletions(-) (limited to 'arch/x86/kernel') diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h index e98f66f35635..c163215abb9a 100644 --- a/arch/x86/include/asm/mshyperv.h +++ b/arch/x86/include/asm/mshyperv.h @@ -17,7 +17,7 @@ void hyperv_callback_vector(void); #define trace_hyperv_callback_vector hyperv_callback_vector #endif void hyperv_vector_handler(struct pt_regs *regs); -int hv_setup_vmbus_irq(int irq, irq_handler_t handler, void *dev_id); -void hv_remove_vmbus_irq(int irq, void *dev_id); +void hv_setup_vmbus_irq(void (*handler)(void)); +void hv_remove_vmbus_irq(void); #endif diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c index a6f5f351f7af..b4dcca124918 100644 --- a/arch/x86/kernel/cpu/mshyperv.c +++ b/arch/x86/kernel/cpu/mshyperv.c @@ -32,7 +32,7 @@ struct ms_hyperv_info ms_hyperv; EXPORT_SYMBOL_GPL(ms_hyperv); #if IS_ENABLED(CONFIG_HYPERV) -static irq_handler_t vmbus_handler; +static void (*vmbus_handler)(void); void hyperv_vector_handler(struct pt_regs *regs) { @@ -49,7 +49,7 @@ void hyperv_vector_handler(struct pt_regs *regs) set_irq_regs(old_regs); } -int hv_setup_vmbus_irq(int irq, irq_handler_t handler, void *dev_id) +void hv_setup_vmbus_irq(void (*handler)(void)) { vmbus_handler = handler; /* @@ -61,7 +61,7 @@ int hv_setup_vmbus_irq(int irq, irq_handler_t handler, void *dev_id) hyperv_callback_vector); } -void hv_remove_vmbus_irq(int irq, void *dev_id) +void hv_remove_vmbus_irq(void) { /* We have no way to deallocate the interrupt gate */ vmbus_handler = NULL; diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index 5a6909fff1c1..3f0a95290e14 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -615,7 +615,7 @@ static void vmbus_on_msg_dpc(unsigned long data) } } -static irqreturn_t vmbus_isr(int irq, void *dev_id) +static void vmbus_isr(void) { int cpu = smp_processor_id(); void *page_addr; @@ -625,7 +625,7 @@ static irqreturn_t vmbus_isr(int irq, void *dev_id) page_addr = hv_context.synic_event_page[cpu]; if (page_addr == NULL) - return IRQ_NONE; + return; event = (union hv_synic_event_flags *)page_addr + VMBUS_MESSAGE_SINT; @@ -661,15 +661,8 @@ static irqreturn_t vmbus_isr(int irq, void *dev_id) msg = (struct hv_message *)page_addr + VMBUS_MESSAGE_SINT; /* Check if there are actual msgs to be processed */ - if (msg->header.message_type != HVMSG_NONE) { - handled = true; + if (msg->header.message_type != HVMSG_NONE) tasklet_schedule(&msg_dpc); - } - - if (handled) - return IRQ_HANDLED; - else - return IRQ_NONE; } /* @@ -698,12 +691,7 @@ static int vmbus_bus_init(int irq) if (ret) goto err_cleanup; - ret = hv_setup_vmbus_irq(irq, vmbus_isr, hv_acpi_dev); - - if (ret != 0) { - pr_err("Unable to request IRQ %d\n", irq); - goto err_unregister; - } + hv_setup_vmbus_irq(vmbus_isr); ret = hv_synic_alloc(); if (ret) @@ -723,9 +711,8 @@ static int vmbus_bus_init(int irq) err_alloc: hv_synic_free(); - hv_remove_vmbus_irq(irq, hv_acpi_dev); + hv_remove_vmbus_irq(); -err_unregister: bus_unregister(&hv_bus); err_cleanup: @@ -917,7 +904,6 @@ static int __init hv_acpi_init(void) /* * Get irq resources first. */ - ret = acpi_bus_register_driver(&vmbus_acpi_driver); if (ret) @@ -948,7 +934,7 @@ cleanup: static void __exit vmbus_exit(void) { - hv_remove_vmbus_irq(irq, hv_acpi_dev); + hv_remove_vmbus_irq(); vmbus_free_channels(); bus_unregister(&hv_bus); hv_cleanup(); -- cgit v1.2.3