Merge tag 'kvm-s390-next-6.7-1' of https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

- nested page table management performance counters

Author: bonzini

arch/s390/include/asm/kvm_host.h

@@ -777,6 +777,13 @@ struct kvm_vm_stat {
 	u64 inject_service_signal;
 	u64 inject_virtio;
 	u64 aen_forward;
+	u64 gmap_shadow_create;
+	u64 gmap_shadow_reuse;
+	u64 gmap_shadow_r1_entry;
+	u64 gmap_shadow_r2_entry;
+	u64 gmap_shadow_r3_entry;
+	u64 gmap_shadow_sg_entry;
+	u64 gmap_shadow_pg_entry;
 };
 
 struct kvm_arch_memory_slot {

arch/s390/kvm/gaccess.c

@@ -1382,6 +1382,7 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
 				  unsigned long *pgt, int *dat_protection,
 				  int *fake)
 {
+	struct kvm *kvm;
 	struct gmap *parent;
 	union asce asce;
 	union vaddress vaddr;
@@ -1390,6 +1391,7 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
 
 	*fake = 0;
 	*dat_protection = 0;
+	kvm = sg->private;
 	parent = sg->parent;
 	vaddr.addr = saddr;
 	asce.val = sg->orig_asce;
@@ -1450,6 +1452,7 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
 		rc = gmap_shadow_r2t(sg, saddr, rfte.val, *fake);
 		if (rc)
 			return rc;
+		kvm->stat.gmap_shadow_r1_entry++;
 	}
 		fallthrough;
 	case ASCE_TYPE_REGION2: {
@@ -1478,6 +1481,7 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
 		rc = gmap_shadow_r3t(sg, saddr, rste.val, *fake);
 		if (rc)
 			return rc;
+		kvm->stat.gmap_shadow_r2_entry++;
 	}
 		fallthrough;
 	case ASCE_TYPE_REGION3: {
@@ -1515,6 +1519,7 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
 		rc = gmap_shadow_sgt(sg, saddr, rtte.val, *fake);
 		if (rc)
 			return rc;
+		kvm->stat.gmap_shadow_r3_entry++;
 	}
 		fallthrough;
 	case ASCE_TYPE_SEGMENT: {
@@ -1548,6 +1553,7 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
 		rc = gmap_shadow_pgt(sg, saddr, ste.val, *fake);
 		if (rc)
 			return rc;
+		kvm->stat.gmap_shadow_sg_entry++;
 	}
 	}
 	/* Return the parent address of the page table */
@@ -1618,6 +1624,7 @@ int kvm_s390_shadow_fault(struct kvm_vcpu *vcpu, struct gmap *sg,
 	pte.p |= dat_protection;
 	if (!rc)
 		rc = gmap_shadow_page(sg, saddr, __pte(pte.val));
+	vcpu->kvm->stat.gmap_shadow_pg_entry++;
 	ipte_unlock(vcpu->kvm);
 	mmap_read_unlock(sg->mm);
 	return rc;

arch/s390/kvm/kvm-s390.c

@@ -66,7 +66,14 @@ const struct _kvm_stats_desc kvm_vm_stats_desc[] = {
 	STATS_DESC_COUNTER(VM, inject_pfault_done),
 	STATS_DESC_COUNTER(VM, inject_service_signal),
 	STATS_DESC_COUNTER(VM, inject_virtio),
-	STATS_DESC_COUNTER(VM, aen_forward)
+	STATS_DESC_COUNTER(VM, aen_forward),
+	STATS_DESC_COUNTER(VM, gmap_shadow_reuse),
+	STATS_DESC_COUNTER(VM, gmap_shadow_create),
+	STATS_DESC_COUNTER(VM, gmap_shadow_r1_entry),
+	STATS_DESC_COUNTER(VM, gmap_shadow_r2_entry),
+	STATS_DESC_COUNTER(VM, gmap_shadow_r3_entry),
+	STATS_DESC_COUNTER(VM, gmap_shadow_sg_entry),
+	STATS_DESC_COUNTER(VM, gmap_shadow_pg_entry),
 };
 
 const struct kvm_stats_header kvm_vm_stats_header = {
@@ -4053,6 +4060,8 @@ static void kvm_gmap_notifier(struct gmap *gmap, unsigned long start,
 	unsigned long prefix;
 	unsigned long i;
 
+	trace_kvm_s390_gmap_notifier(start, end, gmap_is_shadow(gmap));
+
 	if (gmap_is_shadow(gmap))
 		return;
 	if (start >= 1UL << 31)

arch/s390/kvm/trace-s390.h

@@ -333,6 +333,29 @@ TRACE_EVENT(kvm_s390_airq_suppressed,
 		      __entry->id, __entry->isc)
 	);
 
+/*
+ * Trace point for gmap notifier calls.
+ */
+TRACE_EVENT(kvm_s390_gmap_notifier,
+	    TP_PROTO(unsigned long start, unsigned long end, unsigned int shadow),
+	    TP_ARGS(start, end, shadow),
+
+	    TP_STRUCT__entry(
+		    __field(unsigned long, start)
+		    __field(unsigned long, end)
+		    __field(unsigned int, shadow)
+		    ),
+
+	    TP_fast_assign(
+		    __entry->start = start;
+		    __entry->end = end;
+		    __entry->shadow = shadow;
+		    ),
+
+	    TP_printk("gmap notified (start:0x%lx end:0x%lx shadow:%d)",
+		      __entry->start, __entry->end, __entry->shadow)
+	);
+
 
 #endif /* _TRACE_KVMS390_H */
 

arch/s390/kvm/vsie.c

@@ -1214,15 +1214,18 @@ static int acquire_gmap_shadow(struct kvm_vcpu *vcpu,
 	 * we're holding has been unshadowed. If the gmap is still valid,
 	 * we can safely reuse it.
 	 */
-	if (vsie_page->gmap && gmap_shadow_valid(vsie_page->gmap, asce, edat))
+	if (vsie_page->gmap && gmap_shadow_valid(vsie_page->gmap, asce, edat)) {
+		vcpu->kvm->stat.gmap_shadow_reuse++;
 		return 0;
+	}
 
 	/* release the old shadow - if any, and mark the prefix as unmapped */
 	release_gmap_shadow(vsie_page);
 	gmap = gmap_shadow(vcpu->arch.gmap, asce, edat);
 	if (IS_ERR(gmap))
 		return PTR_ERR(gmap);
 	gmap->private = vcpu->kvm;
+	vcpu->kvm->stat.gmap_shadow_create++;
 	WRITE_ONCE(vsie_page->gmap, gmap);
 	return 0;
 }