From 9a9ab3cc00dc0c338e3ab96f75a0e1a3c1aa3c27 Mon Sep 17 00:00:00 2001 From: Stefano Stabellini Date: Thu, 25 Apr 2013 16:17:04 +0000 Subject: [PATCH] xen/arm: SMP support Map vcpu_info using VCPUOP_register_vcpu_info on all the online vcpus, make sure the allocated struct doesn't cross a page boundary. Call enable_percpu_irq on every cpu. Changes in v5: - allocate xen_vcpu_info dynamically, aligning it to the size of the struct; - use VCPUOP_register_vcpu_info on cpu0 too. Changed in v2: - move the percpu variable argument fix to a separate patch; - remove unused variable. Signed-off-by: Stefano Stabellini --- arch/arm/xen/enlighten.c | 48 +++++++++++++++++++++++++++++++++++----- 1 file changed, 42 insertions(+), 6 deletions(-) diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c index 82d5e63cb03b..6c87d116df63 100644 --- a/arch/arm/xen/enlighten.c +++ b/arch/arm/xen/enlighten.c @@ -2,6 +2,7 @@ #include #include #include +#include #include #include #include @@ -32,6 +33,7 @@ struct shared_info xen_dummy_shared_info; struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info; DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu); +static struct vcpu_info __percpu *xen_vcpu_info; /* These are unused until we support booting "pre-ballooned" */ unsigned long xen_released_pages; @@ -148,6 +150,29 @@ int xen_unmap_domain_mfn_range(struct vm_area_struct *vma, } EXPORT_SYMBOL_GPL(xen_unmap_domain_mfn_range); +static int __init xen_secondary_init(unsigned int cpu) +{ + struct vcpu_register_vcpu_info info; + struct vcpu_info *vcpup; + int err; + + pr_info("Xen: initializing cpu%d\n", cpu); + vcpup = per_cpu_ptr(xen_vcpu_info, cpu); + + info.mfn = __pa(vcpup) >> PAGE_SHIFT; + info.offset = offset_in_page(vcpup); + + err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info); + if (err) { + pr_debug("register_vcpu_info failed: err=%d\n", err); + } else { + /* This cpu is using the registered vcpu info, even if + later ones fail to. */ + per_cpu(xen_vcpu, cpu) = vcpup; + } + return 0; +} + /* * see Documentation/devicetree/bindings/arm/xen.txt for the * documentation of the Xen Device Tree format. @@ -163,6 +188,7 @@ static int __init xen_guest_init(void) const char *version = NULL; const char *xen_prefix = "xen,xen-"; struct resource res; + int i; node = of_find_compatible_node(NULL, NULL, "xen,xen"); if (!node) { @@ -209,13 +235,18 @@ static int __init xen_guest_init(void) /* xen_vcpu is a pointer to the vcpu_info struct in the shared_info * page, we use it in the event channel upcall and in some pvclock - * related functions. We don't need the vcpu_info placement - * optimizations because we don't use any pv_mmu or pv_irq op on - * HVM. + * related functions. * The shared info contains exactly 1 CPU (the boot CPU). The guest * is required to use VCPUOP_register_vcpu_info to place vcpu info - * for secondary CPUs as they are brought up. */ - per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0]; + * for secondary CPUs as they are brought up. + * For uniformity we use VCPUOP_register_vcpu_info even on cpu0. + */ + xen_vcpu_info = __alloc_percpu(sizeof(struct vcpu_info), + sizeof(struct vcpu_info)); + if (xen_vcpu_info == NULL) + return -ENOMEM; + for_each_online_cpu(i) + xen_secondary_init(i); gnttab_init(); if (!xen_initial_domain()) @@ -231,6 +262,11 @@ static irqreturn_t xen_arm_callback(int irq, void *arg) return IRQ_HANDLED; } +static __init void xen_percpu_enable_events(void *unused) +{ + enable_percpu_irq(xen_events_irq, 0); +} + static int __init xen_init_events(void) { if (!xen_domain() || xen_events_irq < 0) @@ -244,7 +280,7 @@ static int __init xen_init_events(void) return -EINVAL; } - enable_percpu_irq(xen_events_irq, 0); + on_each_cpu(xen_percpu_enable_events, NULL, 0); return 0; } -- 2.30.2