diff options
-rw-r--r-- | arch/x86/include/asm/kvm_host.h | 4 | ||||
-rw-r--r-- | arch/x86/kvm/Kconfig | 1 | ||||
-rw-r--r-- | arch/x86/kvm/mmu/mmu.c | 68 | ||||
-rw-r--r-- | include/linux/kvm_host.h | 6 | ||||
-rw-r--r-- | virt/kvm/kvm_main.c | 103 |
5 files changed, 35 insertions, 147 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 3e8afc82ae2f..e159e44a6a1b 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -26,6 +26,7 @@ #include <linux/irqbypass.h> #include <linux/hyperv.h> #include <linux/kfifo.h> +#include <linux/sched/vhost_task.h> #include <asm/apic.h> #include <asm/pvclock-abi.h> @@ -1442,7 +1443,8 @@ struct kvm_arch { bool sgx_provisioning_allowed; struct kvm_x86_pmu_event_filter __rcu *pmu_event_filter; - struct task_struct *nx_huge_page_recovery_thread; + struct vhost_task *nx_huge_page_recovery_thread; + u64 nx_huge_page_last; #ifdef CONFIG_X86_64 /* The number of TDP MMU pages across all roots. */ diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig index 1ed1e4f5d51c..d93af5390341 100644 --- a/arch/x86/kvm/Kconfig +++ b/arch/x86/kvm/Kconfig @@ -30,6 +30,7 @@ config KVM_X86 select HAVE_KVM_IRQ_BYPASS select HAVE_KVM_IRQ_ROUTING select HAVE_KVM_READONLY_MEM + select VHOST_TASK select KVM_ASYNC_PF select USER_RETURN_NOTIFIER select KVM_MMIO diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index d7b391fe2c23..22e7ad235123 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -7162,7 +7162,7 @@ static int set_nx_huge_pages(const char *val, const struct kernel_param *kp) kvm_mmu_zap_all_fast(kvm); mutex_unlock(&kvm->slots_lock); - wake_up_process(kvm->arch.nx_huge_page_recovery_thread); + vhost_task_wake(kvm->arch.nx_huge_page_recovery_thread); } mutex_unlock(&kvm_lock); } @@ -7291,7 +7291,7 @@ static int set_nx_huge_pages_recovery_param(const char *val, const struct kernel mutex_lock(&kvm_lock); list_for_each_entry(kvm, &vm_list, vm_list) - wake_up_process(kvm->arch.nx_huge_page_recovery_thread); + vhost_task_wake(kvm->arch.nx_huge_page_recovery_thread); mutex_unlock(&kvm_lock); } @@ -7394,62 +7394,56 @@ static void kvm_recover_nx_huge_pages(struct kvm *kvm) srcu_read_unlock(&kvm->srcu, rcu_idx); } -static long get_nx_huge_page_recovery_timeout(u64 start_time) +static void kvm_nx_huge_page_recovery_worker_kill(void *data) { - bool enabled; - uint period; - - enabled = calc_nx_huge_pages_recovery_period(&period); - - return enabled ? start_time + msecs_to_jiffies(period) - get_jiffies_64() - : MAX_SCHEDULE_TIMEOUT; } -static int kvm_nx_huge_page_recovery_worker(struct kvm *kvm, uintptr_t data) +static bool kvm_nx_huge_page_recovery_worker(void *data) { - u64 start_time; + struct kvm *kvm = data; + bool enabled; + uint period; long remaining_time; - while (true) { - start_time = get_jiffies_64(); - remaining_time = get_nx_huge_page_recovery_timeout(start_time); - - set_current_state(TASK_INTERRUPTIBLE); - while (!kthread_should_stop() && remaining_time > 0) { - schedule_timeout(remaining_time); - remaining_time = get_nx_huge_page_recovery_timeout(start_time); - set_current_state(TASK_INTERRUPTIBLE); - } - - set_current_state(TASK_RUNNING); - - if (kthread_should_stop()) - return 0; + enabled = calc_nx_huge_pages_recovery_period(&period); + if (!enabled) + return false; - kvm_recover_nx_huge_pages(kvm); + remaining_time = kvm->arch.nx_huge_page_last + msecs_to_jiffies(period) + - get_jiffies_64(); + if (remaining_time > 0) { + schedule_timeout(remaining_time); + /* check for signals and come back */ + return true; } + + __set_current_state(TASK_RUNNING); + kvm_recover_nx_huge_pages(kvm); + kvm->arch.nx_huge_page_last = get_jiffies_64(); + return true; } int kvm_mmu_post_init_vm(struct kvm *kvm) { - int err; - if (nx_hugepage_mitigation_hard_disabled) return 0; - err = kvm_vm_create_worker_thread(kvm, kvm_nx_huge_page_recovery_worker, 0, - "kvm-nx-lpage-recovery", - &kvm->arch.nx_huge_page_recovery_thread); - if (!err) - kthread_unpark(kvm->arch.nx_huge_page_recovery_thread); + kvm->arch.nx_huge_page_last = get_jiffies_64(); + kvm->arch.nx_huge_page_recovery_thread = vhost_task_create( + kvm_nx_huge_page_recovery_worker, kvm_nx_huge_page_recovery_worker_kill, + kvm, "kvm-nx-lpage-recovery"); - return err; + if (!kvm->arch.nx_huge_page_recovery_thread) + return -ENOMEM; + + vhost_task_start(kvm->arch.nx_huge_page_recovery_thread); + return 0; } void kvm_mmu_pre_destroy_vm(struct kvm *kvm) { if (kvm->arch.nx_huge_page_recovery_thread) - kthread_stop(kvm->arch.nx_huge_page_recovery_thread); + vhost_task_stop(kvm->arch.nx_huge_page_recovery_thread); } #ifdef CONFIG_KVM_GENERIC_MEMORY_ATTRIBUTES diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 03e4d26e3bcc..401439bb21e3 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -2425,12 +2425,6 @@ static inline int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu) } #endif /* CONFIG_HAVE_KVM_VCPU_RUN_PID_CHANGE */ -typedef int (*kvm_vm_thread_fn_t)(struct kvm *kvm, uintptr_t data); - -int kvm_vm_create_worker_thread(struct kvm *kvm, kvm_vm_thread_fn_t thread_fn, - uintptr_t data, const char *name, - struct task_struct **thread_ptr); - #ifdef CONFIG_KVM_XFER_TO_GUEST_WORK static inline void kvm_handle_signal_exit(struct kvm_vcpu *vcpu) { diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 27186b06518a..de2c11dae231 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -6426,106 +6426,3 @@ void kvm_exit(void) kvm_irqfd_exit(); } EXPORT_SYMBOL_GPL(kvm_exit); - -struct kvm_vm_worker_thread_context { - struct kvm *kvm; - struct task_struct *parent; - struct completion init_done; - kvm_vm_thread_fn_t thread_fn; - uintptr_t data; - int err; -}; - -static int kvm_vm_worker_thread(void *context) -{ - /* - * The init_context is allocated on the stack of the parent thread, so - * we have to locally copy anything that is needed beyond initialization - */ - struct kvm_vm_worker_thread_context *init_context = context; - struct task_struct *parent; - struct kvm *kvm = init_context->kvm; - kvm_vm_thread_fn_t thread_fn = init_context->thread_fn; - uintptr_t data = init_context->data; - int err; - - err = kthread_park(current); - /* kthread_park(current) is never supposed to return an error */ - WARN_ON(err != 0); - if (err) - goto init_complete; - - err = cgroup_attach_task_all(init_context->parent, current); - if (err) { - kvm_err("%s: cgroup_attach_task_all failed with err %d\n", - __func__, err); - goto init_complete; - } - - set_user_nice(current, task_nice(init_context->parent)); - -init_complete: - init_context->err = err; - complete(&init_context->init_done); - init_context = NULL; - - if (err) - goto out; - - /* Wait to be woken up by the spawner before proceeding. */ - kthread_parkme(); - - if (!kthread_should_stop()) - err = thread_fn(kvm, data); - -out: - /* - * Move kthread back to its original cgroup to prevent it lingering in - * the cgroup of the VM process, after the latter finishes its - * execution. - * - * kthread_stop() waits on the 'exited' completion condition which is - * set in exit_mm(), via mm_release(), in do_exit(). However, the - * kthread is removed from the cgroup in the cgroup_exit() which is - * called after the exit_mm(). This causes the kthread_stop() to return - * before the kthread actually quits the cgroup. - */ - rcu_read_lock(); - parent = rcu_dereference(current->real_parent); - get_task_struct(parent); - rcu_read_unlock(); - cgroup_attach_task_all(parent, current); - put_task_struct(parent); - - return err; -} - -int kvm_vm_create_worker_thread(struct kvm *kvm, kvm_vm_thread_fn_t thread_fn, - uintptr_t data, const char *name, - struct task_struct **thread_ptr) -{ - struct kvm_vm_worker_thread_context init_context = {}; - struct task_struct *thread; - - *thread_ptr = NULL; - init_context.kvm = kvm; - init_context.parent = current; - init_context.thread_fn = thread_fn; - init_context.data = data; - init_completion(&init_context.init_done); - - thread = kthread_run(kvm_vm_worker_thread, &init_context, - "%s-%d", name, task_pid_nr(current)); - if (IS_ERR(thread)) - return PTR_ERR(thread); - - /* kthread_run is never supposed to return NULL */ - WARN_ON(thread == NULL); - - wait_for_completion(&init_context.init_done); - - if (!init_context.err) - *thread_ptr = thread; - - return init_context.err; -} |