KVM: PPC: Book3S HV: Add ICP real mode counters

Add two counters to count how often we generate real-mode ICS resend
and reject events. The counters provide some performance statistics
that could be used in the future to consider if the real mode functions
need further optimizing. The counters are displayed as part of IPC and
ICP state provided by /sys/debug/kernel/powerpc/kvm* for each VM.

Also added two counters that count (approximately) how many times we
don't find an ICP or ICS we're looking for. These are not currently
exposed through sysfs, but can be useful when debugging crashes.

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>

1 files changed, 7 insertions, 0 deletions

diff --git a/arch/powerpc/kvm/book3s_hv_rm_xics.c b/arch/powerpc/kvm/book3s_hv_rm_xics.c
index 73bbe9246512..6dded8c75234 100644
--- a/arch/powerpc/kvm/book3s_hv_rm_xics.c
+++ b/arch/powerpc/kvm/book3s_hv_rm_xics.c
@@ -227,6 +227,7 @@ static void icp_rm_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp,
 	ics = kvmppc_xics_find_ics(xics, new_irq, &src);
 	if (!ics) {
 		/* Unsafe increment, but this does not need to be accurate */
+		xics->err_noics++;
 		return;
 	}
 	state = &ics->irq_state[src];
@@ -239,6 +240,7 @@ static void icp_rm_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp,
 		icp = kvmppc_xics_find_server(xics->kvm, state->server);
 		if (!icp) {
 			/* Unsafe increment again*/
+			xics->err_noicp++;
 			goto out;
 		}
 	}
@@ -383,6 +385,7 @@ static void icp_rm_down_cppr(struct kvmppc_xics *xics, struct kvmppc_icp *icp,
 	 * separately here as well.
 	 */
 	if (resend) {
+		icp->n_check_resend++;
 		icp_rm_check_resend(xics, icp);
 	}
 }
@@ -500,11 +503,13 @@ int kvmppc_rm_h_ipi(struct kvm_vcpu *vcpu, unsigned long server,
 
 	/* Handle reject in real mode */
 	if (reject && reject != XICS_IPI) {
+		this_icp->n_reject++;
 		icp_rm_deliver_irq(xics, icp, reject);
 	}
 
 	/* Handle resends in real mode */
 	if (resend) {
+		this_icp->n_check_resend++;
 		icp_rm_check_resend(xics, icp);
 	}
 
@@ -566,6 +571,7 @@ int kvmppc_rm_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr)
 	 * attempt (see comments in icp_rm_deliver_irq).
 	 */
 	if (reject && reject != XICS_IPI) {
+		icp->n_reject++;
 		icp_rm_deliver_irq(xics, icp, reject);
 	}
  bail:
@@ -616,6 +622,7 @@ int kvmppc_rm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr)
 
 	/* Still asserted, resend it */
 	if (state->asserted) {
+		icp->n_reject++;
 		icp_rm_deliver_irq(xics, icp, irq);
 	}