cxgb4: rework queue config and MSI-X allocation

Simplify queue configuration and MSI-X allocation logic. Use a single
MSI-X information table for both NIC and ULDs. Remove hard-coded
MSI-X indices for firmware event queue and non data interrupts.
Instead, use the MSI-X bitmap to obtain a free MSI-X index
dynamically. Save each Rxq's index into the MSI-X information table,
within the Rxq structures themselves, for easier cleanup.
Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/chelsio/cxgb4/cxgb4.h

@@ -712,6 +712,7 @@ struct sge_eth_rxq {                /* SW Ethernet Rx queue */
 	struct sge_rspq rspq;
 	struct sge_fl fl;
 	struct sge_eth_stats stats;
+	struct msix_info *msix;
 } ____cacheline_aligned_in_smp;
 
 struct sge_ofld_stats {             /* offload queue statistics */
@@ -725,6 +726,7 @@ struct sge_ofld_rxq {               /* SW offload Rx queue */
 	struct sge_rspq rspq;
 	struct sge_fl fl;
 	struct sge_ofld_stats stats;
+	struct msix_info *msix;
 } ____cacheline_aligned_in_smp;
 
 struct tx_desc {
@@ -789,7 +791,6 @@ struct sge_ctrl_txq {               /* state for an SGE control Tx queue */
 struct sge_uld_rxq_info {
 	char name[IFNAMSIZ];	/* name of ULD driver */
 	struct sge_ofld_rxq *uldrxq; /* Rxq's for ULD */
-	u16 *msix_tbl;		/* msix_tbl for uld */
 	u16 *rspq_id;		/* response queue id's of rxq */
 	u16 nrxq;		/* # of ingress uld queues */
 	u16 nciq;		/* # of completion queues */
@@ -842,6 +843,9 @@ struct sge {
 	unsigned long *blocked_fl;
 	struct timer_list rx_timer; /* refills starving FLs */
 	struct timer_list tx_timer; /* checks Tx queues */
+
+	int fwevtq_msix_idx; /* Index to firmware event queue MSI-X info */
+	int nd_msix_idx; /* Index to non-data interrupts MSI-X info */
 };
 
 #define for_each_ethrxq(sge, i) for (i = 0; i < (sge)->ethqsets; i++)
@@ -871,13 +875,13 @@ struct hash_mac_addr {
 	unsigned int iface_mac;
 };
 
-struct uld_msix_bmap {
+struct msix_bmap {
 	unsigned long *msix_bmap;
 	unsigned int mapsize;
 	spinlock_t lock; /* lock for acquiring bitmap */
 };
 
-struct uld_msix_info {
+struct msix_info {
 	unsigned short vec;
 	char desc[IFNAMSIZ + 10];
 	unsigned int idx;
@@ -946,14 +950,9 @@ struct adapter {
 	struct cxgb4_virt_res vres;
 	unsigned int swintr;
 
-	struct msix_info {
-		unsigned short vec;
-		char desc[IFNAMSIZ + 10];
-		cpumask_var_t aff_mask;
-	} msix_info[MAX_INGQ + 1];
-	struct uld_msix_info *msix_info_ulds; /* msix info for uld's */
-	struct uld_msix_bmap msix_bmap_ulds; /* msix bitmap for all uld */
-	int msi_idx;
+	/* MSI-X Info for NIC and OFLD queues */
+	struct msix_info *msix_info;
+	struct msix_bmap msix_bmap;
 
 	struct doorbell_stats db_stats;
 	struct sge sge;
@@ -1954,5 +1953,6 @@ int cxgb4_alloc_raw_mac_filt(struct adapter *adap,
 int cxgb4_update_mac_filt(struct port_info *pi, unsigned int viid,
 			  int *tcam_idx, const u8 *addr,
 			  bool persistent, u8 *smt_idx);
-
+int cxgb4_get_msix_idx_from_bmap(struct adapter *adap);
+void cxgb4_free_msix_idx_in_bmap(struct adapter *adap, u32 msix_idx);
 #endif /* __CXGB4_H__ */

drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.c

@@ -53,35 +53,6 @@
 
 #define for_each_uldrxq(m, i) for (i = 0; i < ((m)->nrxq + (m)->nciq); i++)
 
-static int get_msix_idx_from_bmap(struct adapter *adap)
-{
-	struct uld_msix_bmap *bmap = &adap->msix_bmap_ulds;
-	unsigned long flags;
-	unsigned int msix_idx;
-
-	spin_lock_irqsave(&bmap->lock, flags);
-	msix_idx = find_first_zero_bit(bmap->msix_bmap, bmap->mapsize);
-	if (msix_idx < bmap->mapsize) {
-		__set_bit(msix_idx, bmap->msix_bmap);
-	} else {
-		spin_unlock_irqrestore(&bmap->lock, flags);
-		return -ENOSPC;
-	}
-
-	spin_unlock_irqrestore(&bmap->lock, flags);
-	return msix_idx;
-}
-
-static void free_msix_idx_in_bmap(struct adapter *adap, unsigned int msix_idx)
-{
-	struct uld_msix_bmap *bmap = &adap->msix_bmap_ulds;
-	unsigned long flags;
-
-	spin_lock_irqsave(&bmap->lock, flags);
-	__clear_bit(msix_idx, bmap->msix_bmap);
-	spin_unlock_irqrestore(&bmap->lock, flags);
-}
-
 /* Flush the aggregated lro sessions */
 static void uldrx_flush_handler(struct sge_rspq *q)
 {
@@ -138,9 +109,9 @@ static int alloc_uld_rxqs(struct adapter *adap,
 			  struct sge_uld_rxq_info *rxq_info, bool lro)
 {
 	unsigned int nq = rxq_info->nrxq + rxq_info->nciq;
-	int i, err, msi_idx, que_idx = 0, bmap_idx = 0;
 	struct sge_ofld_rxq *q = rxq_info->uldrxq;
 	unsigned short *ids = rxq_info->rspq_id;
+	int i, err, msi_idx, que_idx = 0;
 	struct sge *s = &adap->sge;
 	unsigned int per_chan;
 
@@ -159,12 +130,18 @@ static int alloc_uld_rxqs(struct adapter *adap,
 		}
 
 		if (msi_idx >= 0) {
-			bmap_idx = get_msix_idx_from_bmap(adap);
-			if (bmap_idx < 0) {
+			msi_idx = cxgb4_get_msix_idx_from_bmap(adap);
+			if (msi_idx < 0) {
 				err = -ENOSPC;
 				goto freeout;
 			}
-			msi_idx = adap->msix_info_ulds[bmap_idx].idx;
+
+			snprintf(adap->msix_info[msi_idx].desc,
+				 sizeof(adap->msix_info[msi_idx].desc),
+				 "%s-%s%d",
+				 adap->port[0]->name, rxq_info->name, i);
+
+			q->msix = &adap->msix_info[msi_idx];
 		}
 		err = t4_sge_alloc_rxq(adap, &q->rspq, false,
 				       adap->port[que_idx++ / per_chan],
@@ -175,8 +152,7 @@ static int alloc_uld_rxqs(struct adapter *adap,
 				       0);
 		if (err)
 			goto freeout;
-		if (msi_idx >= 0)
-			rxq_info->msix_tbl[i] = bmap_idx;
+
 		memset(&q->stats, 0, sizeof(q->stats));
 		if (ids)
 			ids[i] = q->rspq.abs_id;
@@ -188,6 +164,8 @@ static int alloc_uld_rxqs(struct adapter *adap,
 		if (q->rspq.desc)
 			free_rspq_fl(adap, &q->rspq,
 				     q->fl.size ? &q->fl : NULL);
+		if (q->msix)
+			cxgb4_free_msix_idx_in_bmap(adap, q->msix->idx);
 	}
 	return err;
 }
@@ -198,14 +176,6 @@ setup_sge_queues_uld(struct adapter *adap, unsigned int uld_type, bool lro)
 	struct sge_uld_rxq_info *rxq_info = adap->sge.uld_rxq_info[uld_type];
 	int i, ret = 0;
 
-	if (adap->flags & CXGB4_USING_MSIX) {
-		rxq_info->msix_tbl = kcalloc((rxq_info->nrxq + rxq_info->nciq),
-					     sizeof(unsigned short),
-					     GFP_KERNEL);
-		if (!rxq_info->msix_tbl)
-			return -ENOMEM;
-	}
-
 	ret = !(!alloc_uld_rxqs(adap, rxq_info, lro));
 
 	/* Tell uP to route control queue completions to rdma rspq */
@@ -261,8 +231,6 @@ static void free_sge_queues_uld(struct adapter *adap, unsigned int uld_type)
 		t4_free_uld_rxqs(adap, rxq_info->nciq,
 				 rxq_info->uldrxq + rxq_info->nrxq);
 	t4_free_uld_rxqs(adap, rxq_info->nrxq, rxq_info->uldrxq);
-	if (adap->flags & CXGB4_USING_MSIX)
-		kfree(rxq_info->msix_tbl);
 }
 
 static int cfg_queues_uld(struct adapter *adap, unsigned int uld_type,
@@ -355,13 +323,12 @@ static int
 request_msix_queue_irqs_uld(struct adapter *adap, unsigned int uld_type)
 {
 	struct sge_uld_rxq_info *rxq_info = adap->sge.uld_rxq_info[uld_type];
-	struct uld_msix_info *minfo;
+	struct msix_info *minfo;
+	unsigned int idx;
 	int err = 0;
-	unsigned int idx, bmap_idx;
 
 	for_each_uldrxq(rxq_info, idx) {
-		bmap_idx = rxq_info->msix_tbl[idx];
-		minfo = &adap->msix_info_ulds[bmap_idx];
+		minfo = rxq_info->uldrxq[idx].msix;
 		err = request_irq(minfo->vec,
 				  t4_sge_intr_msix, 0,
 				  minfo->desc,
@@ -376,10 +343,9 @@ request_msix_queue_irqs_uld(struct adapter *adap, unsigned int uld_type)
 
 unwind:
 	while (idx-- > 0) {
-		bmap_idx = rxq_info->msix_tbl[idx];
-		minfo = &adap->msix_info_ulds[bmap_idx];
+		minfo = rxq_info->uldrxq[idx].msix;
 		cxgb4_clear_msix_aff(minfo->vec, minfo->aff_mask);
-		free_msix_idx_in_bmap(adap, bmap_idx);
+		cxgb4_free_msix_idx_in_bmap(adap, minfo->idx);
 		free_irq(minfo->vec, &rxq_info->uldrxq[idx].rspq);
 	}
 	return err;
@@ -389,33 +355,17 @@ static void
 free_msix_queue_irqs_uld(struct adapter *adap, unsigned int uld_type)
 {
 	struct sge_uld_rxq_info *rxq_info = adap->sge.uld_rxq_info[uld_type];
-	struct uld_msix_info *minfo;
-	unsigned int idx, bmap_idx;
+	struct msix_info *minfo;
+	unsigned int idx;
 
 	for_each_uldrxq(rxq_info, idx) {
-		bmap_idx = rxq_info->msix_tbl[idx];
-		minfo = &adap->msix_info_ulds[bmap_idx];
-
+		minfo = rxq_info->uldrxq[idx].msix;
 		cxgb4_clear_msix_aff(minfo->vec, minfo->aff_mask);
-		free_msix_idx_in_bmap(adap, bmap_idx);
+		cxgb4_free_msix_idx_in_bmap(adap, minfo->idx);
 		free_irq(minfo->vec, &rxq_info->uldrxq[idx].rspq);
 	}
 }
 
-static void name_msix_vecs_uld(struct adapter *adap, unsigned int uld_type)
-{
-	struct sge_uld_rxq_info *rxq_info = adap->sge.uld_rxq_info[uld_type];
-	int n = sizeof(adap->msix_info_ulds[0].desc);
-	unsigned int idx, bmap_idx;
-
-	for_each_uldrxq(rxq_info, idx) {
-		bmap_idx = rxq_info->msix_tbl[idx];
-
-		snprintf(adap->msix_info_ulds[bmap_idx].desc, n, "%s-%s%d",
-			 adap->port[0]->name, rxq_info->name, idx);
-	}
-}
-
 static void enable_rx(struct adapter *adap, struct sge_rspq *q)
 {
 	if (!q)
@@ -750,7 +700,6 @@ void cxgb4_register_uld(enum cxgb4_uld type,
 		if (ret)
 			goto free_queues;
 		if (adap->flags & CXGB4_USING_MSIX) {
-			name_msix_vecs_uld(adap, type);
 			ret = request_msix_queue_irqs_uld(adap, type);
 			if (ret)
 				goto free_rxq;

drivers/net/ethernet/chelsio/cxgb4/sge.c

@@ -4060,6 +4060,10 @@ void t4_free_sge_resources(struct adapter *adap)
 		if (eq->rspq.desc)
 			free_rspq_fl(adap, &eq->rspq,
 				     eq->fl.size ? &eq->fl : NULL);
+		if (eq->msix) {
+			cxgb4_free_msix_idx_in_bmap(adap, eq->msix->idx);
+			eq->msix = NULL;
+		}
 
 		etq = &adap->sge.ethtxq[i];
 		if (etq->q.desc) {
@@ -4086,8 +4090,15 @@ void t4_free_sge_resources(struct adapter *adap)
 		}
 	}
 
-	if (adap->sge.fw_evtq.desc)
+	if (adap->sge.fw_evtq.desc) {
 		free_rspq_fl(adap, &adap->sge.fw_evtq, NULL);
+		if (adap->sge.fwevtq_msix_idx >= 0)
+			cxgb4_free_msix_idx_in_bmap(adap,
+						    adap->sge.fwevtq_msix_idx);
+	}
+
+	if (adap->sge.nd_msix_idx >= 0)
+		cxgb4_free_msix_idx_in_bmap(adap, adap->sge.nd_msix_idx);
 
 	if (adap->sge.intrq.desc)
 		free_rspq_fl(adap, &adap->sge.intrq, NULL);