KVM: s390: deliver floating interrupts in order of priority

This patch makes interrupt handling compliant to the z/Architecture
Principles of Operation with regard to interrupt priorities.

Add a bitmap for pending floating interrupts. Each bit relates to a
interrupt type and its list. A turned on bit indicates that a list
contains items (interrupts) which need to be delivered.  When delivering
interrupts on a cpu we can merge the existing bitmap for cpu-local
interrupts and floating interrupts and have a single mechanism for
delivery.
Currently we have one list for all kinds of floating interrupts and a
corresponding spin lock. This patch adds a separate list per
interrupt type. An exception to this are service signal and machine check
interrupts, as there can be only one pending interrupt at a time.

Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
This commit is contained in:
Jens Freimann 2013-07-03 15:18:35 +02:00 committed by Christian Borntraeger
parent 94aa033efc
commit 6d3da24141
5 changed files with 509 additions and 366 deletions

View file

@ -344,6 +344,11 @@ enum irq_types {
IRQ_PEND_COUNT
};
/* We have 2M for virtio device descriptor pages. Smallest amount of
* memory per page is 24 bytes (1 queue), so (2048*1024) / 24 = 87381
*/
#define KVM_S390_MAX_VIRTIO_IRQS 87381
/*
* Repressible (non-floating) machine check interrupts
* subclass bits in MCIC
@ -421,13 +426,32 @@ struct kvm_s390_local_interrupt {
unsigned long pending_irqs;
};
#define FIRQ_LIST_IO_ISC_0 0
#define FIRQ_LIST_IO_ISC_1 1
#define FIRQ_LIST_IO_ISC_2 2
#define FIRQ_LIST_IO_ISC_3 3
#define FIRQ_LIST_IO_ISC_4 4
#define FIRQ_LIST_IO_ISC_5 5
#define FIRQ_LIST_IO_ISC_6 6
#define FIRQ_LIST_IO_ISC_7 7
#define FIRQ_LIST_PFAULT 8
#define FIRQ_LIST_VIRTIO 9
#define FIRQ_LIST_COUNT 10
#define FIRQ_CNTR_IO 0
#define FIRQ_CNTR_SERVICE 1
#define FIRQ_CNTR_VIRTIO 2
#define FIRQ_CNTR_PFAULT 3
#define FIRQ_MAX_COUNT 4
struct kvm_s390_float_interrupt {
unsigned long pending_irqs;
spinlock_t lock;
struct list_head list;
atomic_t active;
struct list_head lists[FIRQ_LIST_COUNT];
int counters[FIRQ_MAX_COUNT];
struct kvm_s390_mchk_info mchk;
struct kvm_s390_ext_info srv_signal;
int next_rr_cpu;
unsigned long idle_mask[BITS_TO_LONGS(KVM_MAX_VCPUS)];
unsigned int irq_count;
};
struct kvm_hw_wp_info_arch {

File diff suppressed because it is too large Load diff

View file

@ -31,6 +31,7 @@
#include <asm/pgtable.h>
#include <asm/nmi.h>
#include <asm/switch_to.h>
#include <asm/isc.h>
#include <asm/sclp.h>
#include "kvm-s390.h"
#include "gaccess.h"
@ -1069,7 +1070,8 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
goto out_err;
spin_lock_init(&kvm->arch.float_int.lock);
INIT_LIST_HEAD(&kvm->arch.float_int.list);
for (i = 0; i < FIRQ_LIST_COUNT; i++)
INIT_LIST_HEAD(&kvm->arch.float_int.lists[i]);
init_waitqueue_head(&kvm->arch.ipte_wq);
mutex_init(&kvm->arch.ipte_mutex);

View file

@ -178,7 +178,7 @@ int __must_check kvm_s390_inject_vcpu(struct kvm_vcpu *vcpu,
struct kvm_s390_irq *irq);
int __must_check kvm_s390_inject_program_int(struct kvm_vcpu *vcpu, u16 code);
struct kvm_s390_interrupt_info *kvm_s390_get_io_int(struct kvm *kvm,
u64 cr6, u64 schid);
u64 isc_mask, u32 schid);
int kvm_s390_reinject_io_int(struct kvm *kvm,
struct kvm_s390_interrupt_info *inti);
int kvm_s390_mask_adapter(struct kvm *kvm, unsigned int id, bool masked);

View file

@ -294,10 +294,13 @@ static int handle_tpi(struct kvm_vcpu *vcpu)
static int handle_tsch(struct kvm_vcpu *vcpu)
{
struct kvm_s390_interrupt_info *inti;
struct kvm_s390_interrupt_info *inti = NULL;
const u64 isc_mask = 0xffUL << 24; /* all iscs set */
inti = kvm_s390_get_io_int(vcpu->kvm, 0,
vcpu->run->s.regs.gprs[1]);
/* a valid schid has at least one bit set */
if (vcpu->run->s.regs.gprs[1])
inti = kvm_s390_get_io_int(vcpu->kvm, isc_mask,
vcpu->run->s.regs.gprs[1]);
/*
* Prepare exit to userspace.