hv: ptdev: move softirq_dev_entry_list from vm structure to per_cpu region

Using per_cpu list to record ptdev interrupts is more reasonable than
recording them per-vm. It makes dispatching such interrupts more easier
as we now do it in softirq which happens following interrupt context of
each pcpu.

Tracked-On: #3663
Signed-off-by: Jason Chen CJ <jason.cj.chen@intel.com>
Signed-off-by: Shuo A Liu <shuo.a.liu@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>

hypervisor/arch/x86/cpu.c

@@ -248,6 +248,7 @@ void init_pcpu_post(uint16_t pcpu_id)
 		init_interrupt(pcpu_id);
 
 		timer_init();
+		ptdev_init();
 
 		/* Wait for boot processor to signal all secondary cores to continue */
 		wait_sync_change(&pcpu_sync, 0UL);

hypervisor/arch/x86/guest/assign.c

@@ -520,11 +520,8 @@ static void ptirq_handle_intx(struct acrn_vm *vm,
 
 void ptirq_softirq(uint16_t pcpu_id)
 {
-	struct acrn_vcpu *vcpu = per_cpu(vcpu, pcpu_id);
-	struct acrn_vm *vm = vcpu->vm;
-
 	while (1) {
-		struct ptirq_remapping_info *entry = ptirq_dequeue_softirq(vm);
+		struct ptirq_remapping_info *entry = ptirq_dequeue_softirq(pcpu_id);
 		struct ptirq_msi_info *msi;
 
 		if (entry == NULL) {
@@ -541,11 +538,11 @@ void ptirq_softirq(uint16_t pcpu_id)
 
 		/* handle real request */
 		if (entry->intr_type == PTDEV_INTR_INTX) {
-			ptirq_handle_intx(vm, entry);
+			ptirq_handle_intx(entry->vm, entry);
 		} else {
 			if (msi != NULL) {
 				/* TODO: msi destmode check required */
-				(void)vlapic_intr_msi(vm, msi->vmsi_addr.full, msi->vmsi_data.full);
+				(void)vlapic_intr_msi(entry->vm, msi->vmsi_addr.full, msi->vmsi_data.full);
 				dev_dbg(ACRN_DBG_PTIRQ, "dev-assign: irq=0x%x MSI VR: 0x%x-0x%x",
 					entry->allocated_pirq,
 					msi->vmsi_data.bits.vector,

hypervisor/arch/x86/guest/vm.c

@@ -478,8 +478,6 @@ int32_t create_vm(uint16_t vm_id, struct acrn_vm_config *vm_config, struct acrn_
 	if (status == 0) {
 		prepare_epc_vm_memmap(vm);
 
-		INIT_LIST_HEAD(&vm->softirq_dev_entry_list);
-		spinlock_init(&vm->softirq_dev_lock);
 		spinlock_init(&vm->vm_lock);
 
 		vm->arch_vm.vlapic_state = VM_VLAPIC_XAPIC;

hypervisor/common/ptdev.c

@@ -4,6 +4,7 @@
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
+#include <per_cpu.h>
 #include <vm.h>
 #include <softirq.h>
 #include <ptdev.h>
@@ -34,13 +35,13 @@ static void ptirq_enqueue_softirq(struct ptirq_remapping_info *entry)
 	uint64_t rflags;
 
 	/* enqueue request in order, SOFTIRQ_PTDEV will pickup */
-	spinlock_irqsave_obtain(&entry->vm->softirq_dev_lock, &rflags);
+	CPU_INT_ALL_DISABLE(&rflags);
 
 	/* avoid adding recursively */
 	list_del(&entry->softirq_node);
 	/* TODO: assert if entry already in list */
-	list_add_tail(&entry->softirq_node, &entry->vm->softirq_dev_entry_list);
-	spinlock_irqrestore_release(&entry->vm->softirq_dev_lock, rflags);
+	list_add_tail(&entry->softirq_node, &get_cpu_var(softirq_dev_entry_list));
+	CPU_INT_ALL_RESTORE(rflags);
 	fire_softirq(SOFTIRQ_PTDEV);
 }
 
@@ -51,15 +52,15 @@ static void ptirq_intr_delay_callback(void *data)
 	ptirq_enqueue_softirq(entry);
 }
 
-struct ptirq_remapping_info *ptirq_dequeue_softirq(struct acrn_vm *vm)
+struct ptirq_remapping_info *ptirq_dequeue_softirq(uint16_t pcpu_id)
 {
 	uint64_t rflags;
 	struct ptirq_remapping_info *entry = NULL;
 
-	spinlock_irqsave_obtain(&vm->softirq_dev_lock, &rflags);
+	CPU_INT_ALL_DISABLE(&rflags);
 
-	while (!list_empty(&vm->softirq_dev_entry_list)) {
-		entry = get_first_item(&vm->softirq_dev_entry_list, struct ptirq_remapping_info, softirq_node);
+	while (!list_empty(&get_cpu_var(softirq_dev_entry_list))) {
+		entry = get_first_item(&per_cpu(softirq_dev_entry_list, pcpu_id), struct ptirq_remapping_info, softirq_node);
 
 		list_del_init(&entry->softirq_node);
 
@@ -73,7 +74,7 @@ struct ptirq_remapping_info *ptirq_dequeue_softirq(struct acrn_vm *vm)
 		}
 	}
 
-	spinlock_irqrestore_release(&vm->softirq_dev_lock, rflags);
+	CPU_INT_ALL_RESTORE(rflags);
 	return entry;
 }
 
@@ -106,10 +107,10 @@ void ptirq_release_entry(struct ptirq_remapping_info *entry)
 {
 	uint64_t rflags;
 
-	spinlock_irqsave_obtain(&entry->vm->softirq_dev_lock, &rflags);
+	CPU_INT_ALL_DISABLE(&rflags);
 	list_del_init(&entry->softirq_node);
 	del_timer(&entry->intr_delay_timer);
-	spinlock_irqrestore_release(&entry->vm->softirq_dev_lock, rflags);
+	CPU_INT_ALL_RESTORE(rflags);
 
 	bitmap_clear_nolock((entry->ptdev_entry_id) & 0x3FU,
 		&ptirq_entry_bitmaps[((entry->ptdev_entry_id) & 0x3FU) >> 6U]);
@@ -176,10 +177,10 @@ void ptirq_deactivate_entry(struct ptirq_remapping_info *entry)
 void ptdev_init(void)
 {
 	if (get_pcpu_id() == BOOT_CPU_ID) {
-
 		spinlock_init(&ptdev_lock);
 		register_softirq(SOFTIRQ_PTDEV, ptirq_softirq);
 	}
+	INIT_LIST_HEAD(&get_cpu_var(softirq_dev_entry_list));
 }
 
 void ptdev_release_all_entries(const struct acrn_vm *vm)

hypervisor/include/arch/x86/guest/vm.h

@@ -143,8 +143,6 @@ struct acrn_vm {
 
 	uint8_t vrtc_offset;
 
-	spinlock_t softirq_dev_lock;
-	struct list_head softirq_dev_entry_list;
 	uint64_t intr_inject_delay_delta; /* delay of intr injection */
 } __aligned(PAGE_SIZE);
 

hypervisor/include/arch/x86/per_cpu.h

@@ -51,6 +51,7 @@ struct per_cpu_region {
 	uint32_t lapic_ldr;
 	uint32_t softirq_servicing;
 	struct smp_call_info_data smp_call_info;
+	struct list_head softirq_dev_entry_list;
 #ifdef PROFILING_ON
 	struct profiling_info_wrapper profiling_info;
 #endif

hypervisor/include/common/ptdev.h

@@ -154,7 +154,7 @@ void ptirq_softirq(uint16_t pcpu_id);
 void ptdev_init(void);
 void ptdev_release_all_entries(const struct acrn_vm *vm);
 
-struct ptirq_remapping_info *ptirq_dequeue_softirq(struct acrn_vm *vm);
+struct ptirq_remapping_info *ptirq_dequeue_softirq(uint16_t pcpu_id);
 struct ptirq_remapping_info *ptirq_alloc_entry(struct acrn_vm *vm, uint32_t intr_type);
 void ptirq_release_entry(struct ptirq_remapping_info *entry);
 int32_t ptirq_activate_entry(struct ptirq_remapping_info *entry, uint32_t phys_irq);