cxgb4: Make sure that Freelist size is larger than Egress Congestion Threshold

We need to make sure that the Free List Size, in pointers, is at
least 2 Egress Queue Units (8 pointers/each) larger than the SGE's Egress
Congestion Threshold (in pointers).

Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/chelsio/cxgb4/sge.c b/drivers/net/ethernet/chelsio/cxgb4/sge.c
index 0d2edda..517d5b4 100644 (file)
--- a/drivers/net/ethernet/chelsio/cxgb4/sge.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/sge.c
@@ -2473,6 +2473,15 @@ int t4_sge_alloc_rxq(struct adapter *adap, struct sge_rspq *iq, bool fwevtq,
        c.iqaddr = cpu_to_be64(iq->phys_addr);
 
        if (fl) {
+               /* Allocate the ring for the hardware free list (with space
+                * for its status page) along with the associated software
+                * descriptor ring.  The free list size needs to be a multiple
+                * of the Egress Queue Unit and at least 2 Egress Units larger
+                * than the SGE's Egress Congrestion Threshold
+                * (fl_starve_thres - 1).
+                */
+               if (fl->size < s->fl_starve_thres - 1 + 2 * 8)
+                       fl->size = s->fl_starve_thres - 1 + 2 * 8;
                fl->size = roundup(fl->size, 8);
                fl->desc = alloc_ring(adap->pdev_dev, fl->size, sizeof(__be64),
                                      sizeof(struct rx_sw_desc), &fl->addr,

diff --git a/drivers/net/ethernet/chelsio/cxgb4vf/sge.c b/drivers/net/ethernet/chelsio/cxgb4vf/sge.c
index 482f6de..cc92c69 100644 (file)
--- a/drivers/net/ethernet/chelsio/cxgb4vf/sge.c
+++ b/drivers/net/ethernet/chelsio/cxgb4vf/sge.c
@@ -2243,8 +2243,12 @@ int t4vf_sge_alloc_rxq(struct adapter *adapter, struct sge_rspq *rspq,
                 * Allocate the ring for the hardware free list (with space
                 * for its status page) along with the associated software
                 * descriptor ring.  The free list size needs to be a multiple
-                * of the Egress Queue Unit.
+                * of the Egress Queue Unit and at least 2 Egress Units larger
+                * than the SGE's Egress Congrestion Threshold
+                * (fl_starve_thres - 1).
                 */
+               if (fl->size < s->fl_starve_thres - 1 + 2 * FL_PER_EQ_UNIT)
+                       fl->size = s->fl_starve_thres - 1 + 2 * FL_PER_EQ_UNIT;
                fl->size = roundup(fl->size, FL_PER_EQ_UNIT);
                fl->desc = alloc_ring(adapter->pdev_dev, fl->size,
                                      sizeof(__be64), sizeof(struct rx_sw_desc),