1 files changed, 107 insertions, 70 deletions

diff --git a/drivers/infiniband/hw/cxgb4/device.c b/drivers/infiniband/hw/cxgb4/device.c
index 4a033853312e..ba7335fd4ebf 100644
--- a/drivers/infiniband/hw/cxgb4/device.c
+++ b/drivers/infiniband/hw/cxgb4/device.c
@@ -64,6 +64,10 @@ struct uld_ctx {
 static LIST_HEAD(uld_ctx_list);
 static DEFINE_MUTEX(dev_mutex);
 
+#define DB_FC_RESUME_SIZE 64
+#define DB_FC_RESUME_DELAY 1
+#define DB_FC_DRAIN_THRESH 0
+
 static struct dentry *c4iw_debugfs_root;
 
 struct c4iw_debugfs_data {
@@ -282,7 +286,7 @@ static const struct file_operations stag_debugfs_fops = {
 	.llseek  = default_llseek,
 };
 
-static char *db_state_str[] = {"NORMAL", "FLOW_CONTROL", "RECOVERY"};
+static char *db_state_str[] = {"NORMAL", "FLOW_CONTROL", "RECOVERY", "STOPPED"};
 
 static int stats_show(struct seq_file *seq, void *v)
 {
@@ -311,9 +315,10 @@ static int stats_show(struct seq_file *seq, void *v)
 	seq_printf(seq, "  DB FULL: %10llu\n", dev->rdev.stats.db_full);
 	seq_printf(seq, " DB EMPTY: %10llu\n", dev->rdev.stats.db_empty);
 	seq_printf(seq, "  DB DROP: %10llu\n", dev->rdev.stats.db_drop);
-	seq_printf(seq, " DB State: %s Transitions %llu\n",
+	seq_printf(seq, " DB State: %s Transitions %llu FC Interruptions %llu\n",
 		   db_state_str[dev->db_state],
-		   dev->rdev.stats.db_state_transitions);
+		   dev->rdev.stats.db_state_transitions,
+		   dev->rdev.stats.db_fc_interruptions);
 	seq_printf(seq, "TCAM_FULL: %10llu\n", dev->rdev.stats.tcam_full);
 	seq_printf(seq, "ACT_OFLD_CONN_FAILS: %10llu\n",
 		   dev->rdev.stats.act_ofld_conn_fails);
@@ -643,6 +648,12 @@ static int c4iw_rdev_open(struct c4iw_rdev *rdev)
 		printk(KERN_ERR MOD "error %d initializing ocqp pool\n", err);
 		goto err4;
 	}
+	rdev->status_page = (struct t4_dev_status_page *)
+			    __get_free_page(GFP_KERNEL);
+	if (!rdev->status_page) {
+		pr_err(MOD "error allocating status page\n");
+		goto err4;
+	}
 	return 0;
 err4:
 	c4iw_rqtpool_destroy(rdev);
@@ -656,6 +667,7 @@ err1:
 
 static void c4iw_rdev_close(struct c4iw_rdev *rdev)
 {
+	free_page((unsigned long)rdev->status_page);
 	c4iw_pblpool_destroy(rdev);
 	c4iw_rqtpool_destroy(rdev);
 	c4iw_destroy_resource(&rdev->resource);
@@ -703,18 +715,6 @@ static struct c4iw_dev *c4iw_alloc(const struct cxgb4_lld_info *infop)
 		pr_info("%s: On-Chip Queues not supported on this device.\n",
 			pci_name(infop->pdev));
 
-	if (!is_t4(infop->adapter_type)) {
-		if (!allow_db_fc_on_t5) {
-			db_fc_threshold = 100000;
-			pr_info("DB Flow Control Disabled.\n");
-		}
-
-		if (!allow_db_coalescing_on_t5) {
-			db_coalescing_threshold = -1;
-			pr_info("DB Coalescing Disabled.\n");
-		}
-	}
-
 	devp = (struct c4iw_dev *)ib_alloc_device(sizeof(*devp));
 	if (!devp) {
 		printk(KERN_ERR MOD "Cannot allocate ib device\n");
@@ -749,6 +749,7 @@ static struct c4iw_dev *c4iw_alloc(const struct cxgb4_lld_info *infop)
 	spin_lock_init(&devp->lock);
 	mutex_init(&devp->rdev.stats.lock);
 	mutex_init(&devp->db_mutex);
+	INIT_LIST_HEAD(&devp->db_fc_list);
 
 	if (c4iw_debugfs_root) {
 		devp->debugfs_root = debugfs_create_dir(
@@ -977,13 +978,16 @@ static int disable_qp_db(int id, void *p, void *data)
 
 static void stop_queues(struct uld_ctx *ctx)
 {
-	spin_lock_irq(&ctx->dev->lock);
-	if (ctx->dev->db_state == NORMAL) {
-		ctx->dev->rdev.stats.db_state_transitions++;
-		ctx->dev->db_state = FLOW_CONTROL;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ctx->dev->lock, flags);
+	ctx->dev->rdev.stats.db_state_transitions++;
+	ctx->dev->db_state = STOPPED;
+	if (ctx->dev->rdev.flags & T4_STATUS_PAGE_DISABLED)
 		idr_for_each(&ctx->dev->qpidr, disable_qp_db, NULL);
-	}
-	spin_unlock_irq(&ctx->dev->lock);
+	else
+		ctx->dev->rdev.status_page->db_off = 1;
+	spin_unlock_irqrestore(&ctx->dev->lock, flags);
 }
 
 static int enable_qp_db(int id, void *p, void *data)
@@ -994,15 +998,70 @@ static int enable_qp_db(int id, void *p, void *data)
 	return 0;
 }
 
+static void resume_rc_qp(struct c4iw_qp *qp)
+{
+	spin_lock(&qp->lock);
+	t4_ring_sq_db(&qp->wq, qp->wq.sq.wq_pidx_inc);
+	qp->wq.sq.wq_pidx_inc = 0;
+	t4_ring_rq_db(&qp->wq, qp->wq.rq.wq_pidx_inc);
+	qp->wq.rq.wq_pidx_inc = 0;
+	spin_unlock(&qp->lock);
+}
+
+static void resume_a_chunk(struct uld_ctx *ctx)
+{
+	int i;
+	struct c4iw_qp *qp;
+
+	for (i = 0; i < DB_FC_RESUME_SIZE; i++) {
+		qp = list_first_entry(&ctx->dev->db_fc_list, struct c4iw_qp,
+				      db_fc_entry);
+		list_del_init(&qp->db_fc_entry);
+		resume_rc_qp(qp);
+		if (list_empty(&ctx->dev->db_fc_list))
+			break;
+	}
+}
+
 static void resume_queues(struct uld_ctx *ctx)
 {
 	spin_lock_irq(&ctx->dev->lock);
-	if (ctx->dev->qpcnt <= db_fc_threshold &&
-	    ctx->dev->db_state == FLOW_CONTROL) {
-		ctx->dev->db_state = NORMAL;
-		ctx->dev->rdev.stats.db_state_transitions++;
-		idr_for_each(&ctx->dev->qpidr, enable_qp_db, NULL);
+	if (ctx->dev->db_state != STOPPED)
+		goto out;
+	ctx->dev->db_state = FLOW_CONTROL;
+	while (1) {
+		if (list_empty(&ctx->dev->db_fc_list)) {
+			WARN_ON(ctx->dev->db_state != FLOW_CONTROL);
+			ctx->dev->db_state = NORMAL;
+			ctx->dev->rdev.stats.db_state_transitions++;
+			if (ctx->dev->rdev.flags & T4_STATUS_PAGE_DISABLED) {
+				idr_for_each(&ctx->dev->qpidr, enable_qp_db,
+					     NULL);
+			} else {
+				ctx->dev->rdev.status_page->db_off = 0;
+			}
+			break;
+		} else {
+			if (cxgb4_dbfifo_count(ctx->dev->rdev.lldi.ports[0], 1)
+			    < (ctx->dev->rdev.lldi.dbfifo_int_thresh <<
+			       DB_FC_DRAIN_THRESH)) {
+				resume_a_chunk(ctx);
+			}
+			if (!list_empty(&ctx->dev->db_fc_list)) {
+				spin_unlock_irq(&ctx->dev->lock);
+				if (DB_FC_RESUME_DELAY) {
+					set_current_state(TASK_UNINTERRUPTIBLE);
+					schedule_timeout(DB_FC_RESUME_DELAY);
+				}
+				spin_lock_irq(&ctx->dev->lock);
+				if (ctx->dev->db_state != FLOW_CONTROL)
+					break;
+			}
+		}
 	}
+out:
+	if (ctx->dev->db_state != NORMAL)
+		ctx->dev->rdev.stats.db_fc_interruptions++;
 	spin_unlock_irq(&ctx->dev->lock);
 }
 
@@ -1028,12 +1087,12 @@ static int count_qps(int id, void *p, void *data)
 	return 0;
 }
 
-static void deref_qps(struct qp_list qp_list)
+static void deref_qps(struct qp_list *qp_list)
 {
 	int idx;
 
-	for (idx = 0; idx < qp_list.idx; idx++)
-		c4iw_qp_rem_ref(&qp_list.qps[idx]->ibqp);
+	for (idx = 0; idx < qp_list->idx; idx++)
+		c4iw_qp_rem_ref(&qp_list->qps[idx]->ibqp);
 }
 
 static void recover_lost_dbs(struct uld_ctx *ctx, struct qp_list *qp_list)
@@ -1044,17 +1103,22 @@ static void recover_lost_dbs(struct uld_ctx *ctx, struct qp_list *qp_list)
 	for (idx = 0; idx < qp_list->idx; idx++) {
 		struct c4iw_qp *qp = qp_list->qps[idx];
 
+		spin_lock_irq(&qp->rhp->lock);
+		spin_lock(&qp->lock);
 		ret = cxgb4_sync_txq_pidx(qp->rhp->rdev.lldi.ports[0],
 					  qp->wq.sq.qid,
 					  t4_sq_host_wq_pidx(&qp->wq),
 					  t4_sq_wq_size(&qp->wq));
 		if (ret) {
-			printk(KERN_ERR MOD "%s: Fatal error - "
+			pr_err(KERN_ERR MOD "%s: Fatal error - "
 			       "DB overflow recovery failed - "
 			       "error syncing SQ qid %u\n",
 			       pci_name(ctx->lldi.pdev), qp->wq.sq.qid);
+			spin_unlock(&qp->lock);
+			spin_unlock_irq(&qp->rhp->lock);
 			return;
 		}
+		qp->wq.sq.wq_pidx_inc = 0;
 
 		ret = cxgb4_sync_txq_pidx(qp->rhp->rdev.lldi.ports[0],
 					  qp->wq.rq.qid,
@@ -1062,12 +1126,17 @@ static void recover_lost_dbs(struct uld_ctx *ctx, struct qp_list *qp_list)
 					  t4_rq_wq_size(&qp->wq));
 
 		if (ret) {
-			printk(KERN_ERR MOD "%s: Fatal error - "
+			pr_err(KERN_ERR MOD "%s: Fatal error - "
 			       "DB overflow recovery failed - "
 			       "error syncing RQ qid %u\n",
 			       pci_name(ctx->lldi.pdev), qp->wq.rq.qid);
+			spin_unlock(&qp->lock);
+			spin_unlock_irq(&qp->rhp->lock);
 			return;
 		}
+		qp->wq.rq.wq_pidx_inc = 0;
+		spin_unlock(&qp->lock);
+		spin_unlock_irq(&qp->rhp->lock);
 
 		/* Wait for the dbfifo to drain */
 		while (cxgb4_dbfifo_count(qp->rhp->rdev.lldi.ports[0], 1) > 0) {
@@ -1083,36 +1152,22 @@ static void recover_queues(struct uld_ctx *ctx)
 	struct qp_list qp_list;
 	int ret;
 
-	/* lock out kernel db ringers */
-	mutex_lock(&ctx->dev->db_mutex);
-
-	/* put all queues in to recovery mode */
-	spin_lock_irq(&ctx->dev->lock);
-	ctx->dev->db_state = RECOVERY;
-	ctx->dev->rdev.stats.db_state_transitions++;
-	idr_for_each(&ctx->dev->qpidr, disable_qp_db, NULL);
-	spin_unlock_irq(&ctx->dev->lock);
-
 	/* slow everybody down */
 	set_current_state(TASK_UNINTERRUPTIBLE);
 	schedule_timeout(usecs_to_jiffies(1000));
 
-	/* Wait for the dbfifo to completely drain. */
-	while (cxgb4_dbfifo_count(ctx->dev->rdev.lldi.ports[0], 1) > 0) {
-		set_current_state(TASK_UNINTERRUPTIBLE);
-		schedule_timeout(usecs_to_jiffies(10));
-	}
-
 	/* flush the SGE contexts */
 	ret = cxgb4_flush_eq_cache(ctx->dev->rdev.lldi.ports[0]);
 	if (ret) {
 		printk(KERN_ERR MOD "%s: Fatal error - DB overflow recovery failed\n",
 		       pci_name(ctx->lldi.pdev));
-		goto out;
+		return;
 	}
 
 	/* Count active queues so we can build a list of queues to recover */
 	spin_lock_irq(&ctx->dev->lock);
+	WARN_ON(ctx->dev->db_state != STOPPED);
+	ctx->dev->db_state = RECOVERY;
 	idr_for_each(&ctx->dev->qpidr, count_qps, &count);
 
 	qp_list.qps = kzalloc(count * sizeof *qp_list.qps, GFP_ATOMIC);
@@ -1120,7 +1175,7 @@ static void recover_queues(struct uld_ctx *ctx)
 		printk(KERN_ERR MOD "%s: Fatal error - DB overflow recovery failed\n",
 		       pci_name(ctx->lldi.pdev));
 		spin_unlock_irq(&ctx->dev->lock);
-		goto out;
+		return;
 	}
 	qp_list.idx = 0;
 
@@ -1133,29 +1188,13 @@ static void recover_queues(struct uld_ctx *ctx)
 	recover_lost_dbs(ctx, &qp_list);
 
 	/* we're almost done!  deref the qps and clean up */
-	deref_qps(qp_list);
+	deref_qps(&qp_list);
 	kfree(qp_list.qps);
 
-	/* Wait for the dbfifo to completely drain again */
-	while (cxgb4_dbfifo_count(ctx->dev->rdev.lldi.ports[0], 1) > 0) {
-		set_current_state(TASK_UNINTERRUPTIBLE);
-		schedule_timeout(usecs_to_jiffies(10));
-	}
-
-	/* resume the queues */
 	spin_lock_irq(&ctx->dev->lock);
-	if (ctx->dev->qpcnt > db_fc_threshold)
-		ctx->dev->db_state = FLOW_CONTROL;
-	else {
-		ctx->dev->db_state = NORMAL;
-		idr_for_each(&ctx->dev->qpidr, enable_qp_db, NULL);
-	}
-	ctx->dev->rdev.stats.db_state_transitions++;
+	WARN_ON(ctx->dev->db_state != RECOVERY);
+	ctx->dev->db_state = STOPPED;
 	spin_unlock_irq(&ctx->dev->lock);
-
-out:
-	/* start up kernel db ringers again */
-	mutex_unlock(&ctx->dev->db_mutex);
 }
 
 static int c4iw_uld_control(void *handle, enum cxgb4_control control, ...)
@@ -1165,9 +1204,7 @@ static int c4iw_uld_control(void *handle, enum cxgb4_control control, ...)
 	switch (control) {
 	case CXGB4_CONTROL_DB_FULL:
 		stop_queues(ctx);
-		mutex_lock(&ctx->dev->rdev.stats.lock);
 		ctx->dev->rdev.stats.db_full++;
-		mutex_unlock(&ctx->dev->rdev.stats.lock);
 		break;
 	case CXGB4_CONTROL_DB_EMPTY:
 		resume_queues(ctx);