[PATCH v2 1/2] ceph: update the __update_latency helper

[xiubli@redhat.com]

From: Xiubo Li <xiubli@redhat.com>

Let the __update_latency() helper choose the correcsponding members
according to the metric_type.

URL: https://tracker.ceph.com/issues/49913
Signed-off-by: Xiubo Li <xiubli@redhat.com>
---
 fs/ceph/metric.c | 73 ++++++++++++++++++++++++++++++++++--------------
 1 file changed, 52 insertions(+), 21 deletions(-)

diff --git a/fs/ceph/metric.c b/fs/ceph/metric.c
index 28b6b42ad677..f3e68db08760 100644
--- a/fs/ceph/metric.c
+++ b/fs/ceph/metric.c
@@ -285,19 +285,56 @@ void ceph_metric_destroy(struct ceph_client_metric *m)
 		ceph_put_mds_session(m->session);
 }
 
-static inline void __update_latency(ktime_t *totalp, ktime_t *lsump,
-				    ktime_t *min, ktime_t *max,
-				    ktime_t *sq_sump, ktime_t lat)
-{
-	ktime_t total, avg, sq, lsum;
-
-	total = ++(*totalp);
-	lsum = (*lsump += lat);
+typedef enum {
+	CEPH_METRIC_READ,
+	CEPH_METRIC_WRITE,
+	CEPH_METRIC_METADATA,
+} metric_type;
+
+#define METRIC_UPDATE_MIN_MAX(min, max, new)	\
+{						\
+	if (unlikely(new < min))		\
+		min = new;			\
+	if (unlikely(new > max))		\
+		max = new;			\
+}
 
-	if (unlikely(lat < *min))
-		*min = lat;
-	if (unlikely(lat > *max))
-		*max = lat;
+static inline void __update_latency(struct ceph_client_metric *m,
+				    metric_type type, ktime_t lat)
+{
+	ktime_t total, avg, sq, lsum, *sq_sump;
+
+	switch (type) {
+	case CEPH_METRIC_READ:
+		total = ++m->total_reads;
+		m->read_latency_sum += lat;
+		lsum = m->read_latency_sum;
+		METRIC_UPDATE_MIN_MAX(m->read_latency_min,
+				      m->read_latency_max,
+				      lat);
+		sq_sump = &m->read_latency_sq_sum;
+		break;
+	case CEPH_METRIC_WRITE:
+		total = ++m->total_writes;
+		m->write_latency_sum += lat;
+		lsum = m->write_latency_sum;
+		METRIC_UPDATE_MIN_MAX(m->write_latency_min,
+				      m->write_latency_max,
+				      lat);
+		sq_sump = &m->write_latency_sq_sum;
+		break;
+	case CEPH_METRIC_METADATA:
+		total = ++m->total_metadatas;
+		m->metadata_latency_sum += lat;
+		lsum = m->metadata_latency_sum;
+		METRIC_UPDATE_MIN_MAX(m->metadata_latency_min,
+				      m->metadata_latency_max,
+				      lat);
+		sq_sump = &m->metadata_latency_sq_sum;
+		break;
+	default:
+		return;
+	}
 
 	if (unlikely(total == 1))
 		return;
@@ -320,9 +357,7 @@ void ceph_update_read_metrics(struct ceph_client_metric *m,
 		return;
 
 	spin_lock(&m->read_metric_lock);
-	__update_latency(&m->total_reads, &m->read_latency_sum,
-			 &m->read_latency_min, &m->read_latency_max,
-			 &m->read_latency_sq_sum, lat);
+	__update_latency(m, CEPH_METRIC_READ, lat);
 	spin_unlock(&m->read_metric_lock);
 }
 
@@ -336,9 +371,7 @@ void ceph_update_write_metrics(struct ceph_client_metric *m,
 		return;
 
 	spin_lock(&m->write_metric_lock);
-	__update_latency(&m->total_writes, &m->write_latency_sum,
-			 &m->write_latency_min, &m->write_latency_max,
-			 &m->write_latency_sq_sum, lat);
+	__update_latency(m, CEPH_METRIC_WRITE, lat);
 	spin_unlock(&m->write_metric_lock);
 }
 
@@ -352,8 +385,6 @@ void ceph_update_metadata_metrics(struct ceph_client_metric *m,
 		return;
 
 	spin_lock(&m->metadata_metric_lock);
-	__update_latency(&m->total_metadatas, &m->metadata_latency_sum,
-			 &m->metadata_latency_min, &m->metadata_latency_max,
-			 &m->metadata_latency_sq_sum, lat);
+	__update_latency(m, CEPH_METRIC_METADATA, lat);
 	spin_unlock(&m->metadata_metric_lock);
 }
-- 
2.27.0