Commit 254272ce authored by Ben Gardon's avatar Ben Gardon Committed by Paolo Bonzini
Browse files

kvm: x86: Add memcg accounting to KVM allocations 



There are many KVM kernel memory allocations which are tied to the life of
the VM process and should be charged to the VM process's cgroup. If the
allocations aren't tied to the process, the OOM killer will not know
that killing the process will free the associated kernel memory.
Add __GFP_ACCOUNT flags to many of the allocations which are not yet being
charged to the VM process's cgroup.

Tested:
	Ran all kvm-unit-tests on a 64 bit Haswell machine, the patch
	introduced no new failures.
	Ran a kernel memory accounting test which creates a VM to touch
	memory and then checks that the kernel memory allocated for the
	process is within certain bounds.
	With this patch we account for much more of the vmalloc and slab memory
	allocated for the VM.

There remain a few allocations which should be charged to the VM's
cgroup but are not. In x86, they include:
	vcpu->arch.pio_data
There allocations are unaccounted in this patch because they are mapped
to userspace, and accounting them to a cgroup causes problems. This
should be addressed in a future patch.

Signed-off-by: default avatarBen Gardon <bgardon@google.com>
Reviewed-by: default avatarShakeel Butt <shakeelb@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent b12ce36a

arch/x86/kvm/hyperv.c

+1 −1
Original line number Diff line number Diff line
@@ -1729,7 +1729,7 @@ static int kvm_hv_eventfd_assign(struct kvm *kvm, u32 conn_id, int fd) 


	mutex_lock(&hv->hv_lock);

	ret = idr_alloc(&hv->conn_to_evt, eventfd, conn_id, conn_id + 1,

			GFP_KERNEL);

			GFP_KERNEL_ACCOUNT);

	mutex_unlock(&hv->hv_lock);



	if (ret >= 0)

arch/x86/kvm/i8254.c

+1 −1
Original line number Diff line number Diff line
@@ -653,7 +653,7 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags) 
	pid_t pid_nr;

	int ret;



	pit = kzalloc(sizeof(struct kvm_pit), GFP_KERNEL);

	pit = kzalloc(sizeof(struct kvm_pit), GFP_KERNEL_ACCOUNT);

	if (!pit)

		return NULL;

arch/x86/kvm/i8259.c

+1 −1
Original line number Diff line number Diff line
@@ -583,7 +583,7 @@ int kvm_pic_init(struct kvm *kvm) 
	struct kvm_pic *s;

	int ret;



	s = kzalloc(sizeof(struct kvm_pic), GFP_KERNEL);

	s = kzalloc(sizeof(struct kvm_pic), GFP_KERNEL_ACCOUNT);

	if (!s)

		return -ENOMEM;

	spin_lock_init(&s->lock);

arch/x86/kvm/ioapic.c

+1 −1
Original line number Diff line number Diff line
@@ -622,7 +622,7 @@ int kvm_ioapic_init(struct kvm *kvm) 
	struct kvm_ioapic *ioapic;

	int ret;



	ioapic = kzalloc(sizeof(struct kvm_ioapic), GFP_KERNEL);

	ioapic = kzalloc(sizeof(struct kvm_ioapic), GFP_KERNEL_ACCOUNT);

	if (!ioapic)

		return -ENOMEM;

	spin_lock_init(&ioapic->lock);

arch/x86/kvm/lapic.c

+4 −3
Original line number Diff line number Diff line
@@ -181,7 +181,8 @@ static void recalculate_apic_map(struct kvm *kvm) 
			max_id = max(max_id, kvm_x2apic_id(vcpu->arch.apic));



	new = kvzalloc(sizeof(struct kvm_apic_map) +

	                   sizeof(struct kvm_lapic *) * ((u64)max_id + 1), GFP_KERNEL);

	                   sizeof(struct kvm_lapic *) * ((u64)max_id + 1),

			   GFP_KERNEL_ACCOUNT);



	if (!new)

		goto out;
@@ -2259,13 +2260,13 @@ int kvm_create_lapic(struct kvm_vcpu *vcpu) 
	ASSERT(vcpu != NULL);

	apic_debug("apic_init %d\n", vcpu->vcpu_id);



	apic = kzalloc(sizeof(*apic), GFP_KERNEL);

	apic = kzalloc(sizeof(*apic), GFP_KERNEL_ACCOUNT);

	if (!apic)

		goto nomem;



	vcpu->arch.apic = apic;



	apic->regs = (void *)get_zeroed_page(GFP_KERNEL);

	apic->regs = (void *)get_zeroed_page(GFP_KERNEL_ACCOUNT);

	if (!apic->regs) {

		printk(KERN_ERR "malloc apic regs error for vcpu %x\n",

		       vcpu->vcpu_id);

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