Commit 9a9ab3cc authored by Stefano Stabellini's avatar Stefano Stabellini
Browse files

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: default avatarStefano Stabellini <stefano.stabellini@eu.citrix.com>
parent ea0af613

arch/arm/xen/enlighten.c

+42 −6
Original line number Diff line number Diff line
@@ -2,6 +2,7 @@ 
#include <xen/events.h>

#include <xen/grant_table.h>

#include <xen/hvm.h>

#include <xen/interface/vcpu.h>

#include <xen/interface/xen.h>

#include <xen/interface/memory.h>

#include <xen/interface/hvm/params.h>
@@ -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;

}

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