hv: vcpu: wait and signal vcpu event support

Introduce two kinds of events for each vcpu, VCPU_EVENT_IOREQ: for vcpu waiting for IO request completion VCPU_EVENT_VIRTUAL_INTERRUPT: for vcpu waiting for virtual interrupts events vcpu can wait for such events, and resume to run when the event get signalled. This patch also change IO request waiting/notifying to this way. Tracked-On: #4329 Signed-off-by: Shuo A Liu <shuo.a.liu@intel.com> Acked-by: Eddie Dong <eddie.dong@intel.com>
projectacrn · Jan 7, 2020 · e3c3033 · e3c3033
1 parent 1f23fe3
commit e3c3033
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Showing 4 changed files with 14 additions and 13 deletions.
diff --git a/hypervisor/arch/x86/guest/vcpu.c b/hypervisor/arch/x86/guest/vcpu.c
@@ -802,7 +802,7 @@ void launch_vcpu(struct acrn_vcpu *vcpu)
 /* help function for vcpu create */
 int32_t prepare_vcpu(struct acrn_vm *vm, uint16_t pcpu_id)
 {
-	int32_t ret;
+	int32_t ret, i;
 	struct acrn_vcpu *vcpu = NULL;
 	char thread_name[16];
 
@@ -818,6 +818,9 @@ int32_t prepare_vcpu(struct acrn_vm *vm, uint16_t pcpu_id)
 		vcpu->thread_obj.switch_out = context_switch_out;
 		vcpu->thread_obj.switch_in = context_switch_in;
 		init_thread_data(&vcpu->thread_obj);
+		for (i = 0; i < VCPU_EVENT_NUM; i++) {
+			init_event(&vcpu->events[i]);
+		}
 	}
 
 	return ret;

diff --git a/hypervisor/common/hypercall.c b/hypervisor/common/hypercall.c
@@ -553,8 +553,9 @@ int32_t hcall_notify_ioreq_finish(uint16_t vmid, uint16_t vcpu_id)
 		} else {
 			vcpu = vcpu_from_vid(target_vm, vcpu_id);
 			if (!vcpu->vm->sw.is_completion_polling) {
-				ret = resume_vcpu(vcpu);
+				signal_event(&vcpu->events[VCPU_EVENT_IOREQ]);
 			}
+			ret = 0;
 		}
 	}
 

diff --git a/hypervisor/dm/io_req.c b/hypervisor/dm/io_req.c
@@ -103,14 +103,6 @@ int32_t acrn_insert_request(struct acrn_vcpu *vcpu, const struct io_request *io_
 		}
 		clac();
 
-		/* pause vcpu in notification mode , wait for VHM to handle the MMIO request.
-		 * TODO: when pause_vcpu changed to switch vcpu out directlly, we
-		 * should fix the race issue between req.processed update and vcpu pause
-		 */
-		if (!is_polling) {
-			pause_vcpu(vcpu, VCPU_PAUSED);
-		}
-
 		/* Before updating the vhm_req state, enforce all fill vhm_req operations done */
 		cpu_write_memory_barrier();
 
@@ -136,10 +128,8 @@ int32_t acrn_insert_request(struct acrn_vcpu *vcpu, const struct io_request *io_
 					schedule();
 				}
 			}
-		} else if (need_reschedule(pcpuid_from_vcpu(vcpu))) {
-			schedule();
 		} else {
-			ret = -EINVAL;
+			wait_event(&vcpu->events[VCPU_EVENT_IOREQ]);
 		}
 	} else {
 		ret = -EINVAL;

diff --git a/hypervisor/include/arch/x86/guest/vcpu.h b/hypervisor/include/arch/x86/guest/vcpu.h
@@ -22,6 +22,7 @@
 #include <vlapic.h>
 #include <vmtrr.h>
 #include <schedule.h>
+#include <event.h>
 #include <io_req.h>
 #include <msr.h>
 #include <cpu.h>
@@ -145,6 +146,10 @@ enum vm_cpu_mode {
 	CPU_MODE_64BIT,			/* IA-32E mode (CS.L = 1) */
 };
 
+#define	VCPU_EVENT_IOREQ		0
+#define	VCPU_EVENT_VIRTUAL_INTERRUPT	1
+#define	VCPU_EVENT_NUM			2
+
 enum reset_mode;
 
 /* 2 worlds: 0 for Normal World, 1 for Secure World */
@@ -260,6 +265,8 @@ struct acrn_vcpu {
 
 	uint64_t reg_cached;
 	uint64_t reg_updated;
+
+	struct sched_event events[VCPU_EVENT_NUM];
 } __aligned(PAGE_SIZE);
 
 struct vcpu_dump {