The following commit has been merged into the x86/entry branch of tip: Commit-ID: fad1940a6a856f59b073e8650e02052ce531154c Gitweb: https://git.kernel.org/tip/fad1940a6a856f59b073e8650e02052ce531154c Author: Vitaly Kuznetsov <vkuzn...@redhat.com> AuthorDate: Tue, 28 Apr 2020 11:38:22 +02:00 Committer: Thomas Gleixner <t...@linutronix.de> CommitterDate: Wed, 13 May 2020 21:13:54 +02:00
x86/xen: Split HVM vector callback setup and interrupt gate allocation As a preparatory change for making alloc_intr_gate() __init split xen_callback_vector() into callback vector setup via hypercall (xen_setup_callback_vector()) and interrupt gate allocation (xen_alloc_callback_vector()). xen_setup_callback_vector() is being called twice: on init and upon system resume from xen_hvm_post_suspend(). alloc_intr_gate() only needs to be called once. Suggested-by: Thomas Gleixner <t...@linutronix.de> Signed-off-by: Vitaly Kuznetsov <vkuzn...@redhat.com> Signed-off-by: Thomas Gleixner <t...@linutronix.de> Link: https://lkml.kernel.org/r/20200428093824.1451532-2-vkuzn...@redhat.com --- arch/x86/xen/suspend_hvm.c | 2 +- arch/x86/xen/xen-ops.h | 2 +- drivers/xen/events/events_base.c | 28 +++++++++++++++++----------- 3 files changed, 19 insertions(+), 13 deletions(-) diff --git a/arch/x86/xen/suspend_hvm.c b/arch/x86/xen/suspend_hvm.c index e666b61..5152afe 100644 --- a/arch/x86/xen/suspend_hvm.c +++ b/arch/x86/xen/suspend_hvm.c @@ -13,6 +13,6 @@ void xen_hvm_post_suspend(int suspend_cancelled) xen_hvm_init_shared_info(); xen_vcpu_restore(); } - xen_callback_vector(); + xen_setup_callback_vector(); xen_unplug_emulated_devices(); } diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h index 45a441c..1cc1568 100644 --- a/arch/x86/xen/xen-ops.h +++ b/arch/x86/xen/xen-ops.h @@ -55,7 +55,7 @@ void xen_enable_sysenter(void); void xen_enable_syscall(void); void xen_vcpu_restore(void); -void xen_callback_vector(void); +void xen_setup_callback_vector(void); void xen_hvm_init_shared_info(void); void xen_unplug_emulated_devices(void); diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c index 3a791c8..eb35c3c 100644 --- a/drivers/xen/events/events_base.c +++ b/drivers/xen/events/events_base.c @@ -1639,26 +1639,30 @@ EXPORT_SYMBOL_GPL(xen_set_callback_via); /* Vector callbacks are better than PCI interrupts to receive event * channel notifications because we can receive vector callbacks on any * vcpu and we don't need PCI support or APIC interactions. */ -void xen_callback_vector(void) +void xen_setup_callback_vector(void) { - int rc; uint64_t callback_via; if (xen_have_vector_callback) { callback_via = HVM_CALLBACK_VECTOR(HYPERVISOR_CALLBACK_VECTOR); - rc = xen_set_callback_via(callback_via); - if (rc) { + if (xen_set_callback_via(callback_via)) { pr_err("Request for Xen HVM callback vector failed\n"); xen_have_vector_callback = 0; - return; } - pr_info_once("Xen HVM callback vector for event delivery is enabled\n"); - alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, - xen_hvm_callback_vector); } } + +static __init void xen_alloc_callback_vector(void) +{ + if (!xen_have_vector_callback) + return; + + pr_info("Xen HVM callback vector for event delivery is enabled\n"); + alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, xen_hvm_callback_vector); +} #else -void xen_callback_vector(void) {} +void xen_setup_callback_vector(void) {} +static inline void xen_alloc_callback_vector(void) {} #endif #undef MODULE_PARAM_PREFIX @@ -1692,8 +1696,10 @@ void __init xen_init_IRQ(void) if (xen_initial_domain()) pci_xen_initial_domain(); } - if (xen_feature(XENFEAT_hvm_callback_vector)) - xen_callback_vector(); + if (xen_feature(XENFEAT_hvm_callback_vector)) { + xen_setup_callback_vector(); + xen_alloc_callback_vector(); + } if (xen_hvm_domain()) { native_init_IRQ();
