[PATCH v2 10/12] KVM: selftests / xen: map shared_info using HVA rather than GFN

[Paul Durrant]

From: Paul Durrant <pdurrant@xxxxxxxxxx>

Using the HVA of the shared_info page is more efficient, so if the
capability (KVM_XEN_HVM_CONFIG_SHARED_INFO_HVA) is present use that method
to do the mapping.

Signed-off-by: Paul Durrant <pdurrant@xxxxxxxxxx>
---
Cc: Sean Christopherson <seanjc@xxxxxxxxxx>
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx>

v2:
 - New in this version.
---
 .../selftests/kvm/x86_64/xen_shinfo_test.c    | 50 ++++++++++++++++---
 1 file changed, 43 insertions(+), 7 deletions(-)

diff --git a/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c b/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c
index 49d0c91ee078..fa829d6e0848 100644
--- a/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c
+++ b/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c
@@ -395,6 +395,7 @@ static int cmp_timespec(struct timespec *a, struct timespec *b)
 		return 0;
 }
 
+static struct shared_info *shinfo;
 static struct vcpu_info *vinfo;
 static struct kvm_vcpu *vcpu;
 
@@ -406,7 +407,7 @@ static void handle_alrm(int sig)
 	TEST_FAIL("IRQ delivery timed out");
 }
 
-static void *juggle_shinfo_state(void *arg)
+static void *juggle_shinfo_state_gfn(void *arg)
 {
 	struct kvm_vm *vm = (struct kvm_vm *)arg;
 
@@ -429,6 +430,29 @@ static void *juggle_shinfo_state(void *arg)
 	return NULL;
 }
 
+static void *juggle_shinfo_state_hva(void *arg)
+{
+	struct kvm_vm *vm = (struct kvm_vm *)arg;
+
+	struct kvm_xen_hvm_attr cache_activate = {
+		.type = KVM_XEN_ATTR_TYPE_SHARED_INFO_HVA,
+		.u.shared_info.hva = (unsigned long)shinfo
+	};
+
+	struct kvm_xen_hvm_attr cache_deactivate = {
+		.type = KVM_XEN_ATTR_TYPE_SHARED_INFO_HVA,
+		.u.shared_info.hva = 0
+	};
+
+	for (;;) {
+		__vm_ioctl(vm, KVM_XEN_HVM_SET_ATTR, &cache_activate);
+		__vm_ioctl(vm, KVM_XEN_HVM_SET_ATTR, &cache_deactivate);
+		pthread_testcancel();
+	}
+
+	return NULL;
+}
+
 int main(int argc, char *argv[])
 {
 	struct timespec min_ts, max_ts, vm_ts;
@@ -449,6 +473,7 @@ int main(int argc, char *argv[])
 	bool do_eventfd_tests = !!(xen_caps & KVM_XEN_HVM_CONFIG_EVTCHN_2LEVEL);
 	bool do_evtchn_tests = do_eventfd_tests && !!(xen_caps & KVM_XEN_HVM_CONFIG_EVTCHN_SEND);
 	bool has_vcpu_id = !!(xen_caps & KVM_XEN_HVM_CONFIG_EVTCHN_SEND);
+	bool has_shinfo_hva = !!(xen_caps & KVM_XEN_HVM_CONFIG_SHARED_INFO_HVA);
 
 	clock_gettime(CLOCK_REALTIME, &min_ts);
 
@@ -459,7 +484,7 @@ int main(int argc, char *argv[])
 				    SHINFO_REGION_GPA, SHINFO_REGION_SLOT, 3, 0);
 	virt_map(vm, SHINFO_REGION_GVA, SHINFO_REGION_GPA, 3);
 
-	struct shared_info *shinfo = addr_gpa2hva(vm, SHINFO_VADDR);
+	shinfo = addr_gpa2hva(vm, SHINFO_VADDR);
 
 	int zero_fd = open("/dev/zero", O_RDONLY);
 	TEST_ASSERT(zero_fd != -1, "Failed to open /dev/zero");
@@ -495,10 +520,16 @@ int main(int argc, char *argv[])
 			    "Failed to read back RUNSTATE_UPDATE_FLAG attr");
 	}
 
-	struct kvm_xen_hvm_attr ha = {
-		.type = KVM_XEN_ATTR_TYPE_SHARED_INFO,
-		.u.shared_info.gfn = SHINFO_ADDR / PAGE_SIZE,
-	};
+	struct kvm_xen_hvm_attr ha = {};
+
+	if (has_shinfo_hva) {
+		ha.type = KVM_XEN_ATTR_TYPE_SHARED_INFO_HVA;
+		ha.u.shared_info.hva = (unsigned long)shinfo;
+	} else {
+		ha.type = KVM_XEN_ATTR_TYPE_SHARED_INFO;
+		ha.u.shared_info.gfn = SHINFO_ADDR / PAGE_SIZE;
+	}
+
 	vm_ioctl(vm, KVM_XEN_HVM_SET_ATTR, &ha);
 
 	/*
@@ -902,7 +933,12 @@ int main(int argc, char *argv[])
 				if (verbose)
 					printf("Testing shinfo lock corruption (KVM_XEN_HVM_EVTCHN_SEND)\n");
 
-				ret = pthread_create(&thread, NULL, &juggle_shinfo_state, (void *)vm);
+				if (has_shinfo_hva)
+					ret = pthread_create(&thread, NULL,
+							     &juggle_shinfo_state_hva, (void *)vm);
+				else
+					ret = pthread_create(&thread, NULL,
+							     &juggle_shinfo_state_gfn, (void *)vm);
 				TEST_ASSERT(ret == 0, "pthread_create() failed: %s", strerror(ret));
 
 				struct kvm_irq_routing_xen_evtchn uxe = {
-- 
2.39.2