X-Git-Url: https://git.kernel.dk/?a=blobdiff_plain;f=flow.c;h=c64bb3b27559053d27a79fa2c9a45f68de6e71c2;hb=cb765e413e4d124355c3eec47f7ac8cd314a6951;hp=a8dbfb9bb48e66a991953810d2c25d92eeeacb54;hpb=971caeb177d3bc4f65fa31381bbfb83710bfc690;p=fio.git

diff --git a/flow.c b/flow.c
index a8dbfb9b..c64bb3b2 100644
--- a/flow.c
+++ b/flow.c
@@ -5,9 +5,10 @@
 
 struct fio_flow {
 	unsigned int refs;
-	struct flist_head list;
 	unsigned int id;
-	long long int flow_counter;
+	struct flist_head list;
+	unsigned long flow_counter;
+	unsigned int total_weight;
 };
 
 static struct flist_head *flow_list;
@@ -16,28 +17,40 @@ static struct fio_sem *flow_lock;
 int flow_threshold_exceeded(struct thread_data *td)
 {
 	struct fio_flow *flow = td->flow;
-	long long flow_counter;
+	double flow_counter_ratio, flow_weight_ratio;
 
 	if (!flow)
 		return 0;
 
-	if (td->o.flow > 0)
-		flow_counter = flow->flow_counter;
-	else
-		flow_counter = -flow->flow_counter;
-
-	if (flow_counter > td->o.flow_watermark) {
+	flow_counter_ratio = (double)td->flow_counter /
+		atomic_load_relaxed(&flow->flow_counter);
+	flow_weight_ratio = (double)td->o.flow /
+		atomic_load_relaxed(&flow->total_weight);
+
+	/*
+	 * each thread/process executing a fio job will stall based on the
+	 * expected  user ratio for a given flow_id group. the idea is to keep
+	 * 2 counters, flow and job-specific counter to test if the
+	 * ratio between them is proportional to other jobs in the same flow_id
+	 */
+	if (flow_counter_ratio > flow_weight_ratio) {
 		if (td->o.flow_sleep) {
 			io_u_quiesce(td);
 			usleep(td->o.flow_sleep);
+		} else if (td->o.zone_mode == ZONE_MODE_ZBD) {
+			io_u_quiesce(td);
 		}
 
 		return 1;
 	}
 
-	/* No synchronization needed because it doesn't
-	 * matter if the flow count is slightly inaccurate */
-	flow->flow_counter += td->o.flow;
+	/*
+	 * increment flow(shared counter, therefore atomically)
+	 * and job-specific counter
+	 */
+	atomic_add(&flow->flow_counter, 1);
+	++td->flow_counter;
+
 	return 0;
 }
 
@@ -68,7 +81,8 @@ static struct fio_flow *flow_get(unsigned int id)
 		flow->refs = 0;
 		INIT_FLIST_HEAD(&flow->list);
 		flow->id = id;
-		flow->flow_counter = 0;
+		flow->flow_counter = 1;
+		flow->total_weight = 0;
 
 		flist_add_tail(&flow->list, flow_list);
 	}
@@ -78,14 +92,19 @@ static struct fio_flow *flow_get(unsigned int id)
 	return flow;
 }
 
-static void flow_put(struct fio_flow *flow)
+static void flow_put(struct fio_flow *flow, unsigned long flow_counter,
+				        unsigned int weight)
 {
 	if (!flow_lock)
 		return;
 
 	fio_sem_down(flow_lock);
 
+	atomic_sub(&flow->flow_counter, flow_counter);
+	atomic_sub(&flow->total_weight, weight);
+
 	if (!--flow->refs) {
+		assert(flow->flow_counter == 1);
 		flist_del(&flow->list);
 		sfree(flow);
 	}
@@ -95,14 +114,17 @@ static void flow_put(struct fio_flow *flow)
 
 void flow_init_job(struct thread_data *td)
 {
-	if (td->o.flow)
+	if (td->o.flow) {
 		td->flow = flow_get(td->o.flow_id);
+		td->flow_counter = 0;
+		atomic_add(&td->flow->total_weight, td->o.flow);
+	}
 }
 
 void flow_exit_job(struct thread_data *td)
 {
 	if (td->flow) {
-		flow_put(td->flow);
+		flow_put(td->flow, td->flow_counter, td->o.flow);
 		td->flow = NULL;
 	}
 }