ixgbe_set_rss_queues(adapter);
}
-static int ixgbe_acquire_msix_vectors(struct ixgbe_adapter *adapter,
- int vectors)
+/**
+ * ixgbe_acquire_msix_vectors - acquire MSI-X vectors
+ * @adapter: board private structure
+ *
+ * Attempts to acquire a suitable range of MSI-X vector interrupts. Will
+ * return a negative error code if unable to acquire MSI-X vectors for any
+ * reason.
+ */
+static int ixgbe_acquire_msix_vectors(struct ixgbe_adapter *adapter)
{
- int i, vector_threshold;
+ struct ixgbe_hw *hw = &adapter->hw;
+ int i, vectors, vector_threshold;
+
+ /* We start by asking for one vector per queue pair */
+ vectors = max(adapter->num_rx_queues, adapter->num_tx_queues);
- /* We'll want at least 2 (vector_threshold):
- * 1) TxQ[0] + RxQ[0] handler
- * 2) Other (Link Status Change, etc.)
+ /* It is easy to be greedy for MSI-X vectors. However, it really
+ * doesn't do much good if we have a lot more vectors than CPUs. We'll
+ * be somewhat conservative and only ask for (roughly) the same number
+ * of vectors as there are CPUs.
*/
- vector_threshold = MIN_MSIX_COUNT;
+ vectors = min_t(int, vectors, num_online_cpus());
- /*
- * The more we get, the more we will assign to Tx/Rx Cleanup
- * for the separate queues...where Rx Cleanup >= Tx Cleanup.
- * Right now, we simply care about how many we'll get; we'll
- * set them up later while requesting irq's.
+ /* Some vectors are necessary for non-queue interrupts */
+ vectors += NON_Q_VECTORS;
+
+ /* Hardware can only support a maximum of hw.mac->max_msix_vectors.
+ * With features such as RSS and VMDq, we can easily surpass the
+ * number of Rx and Tx descriptor queues supported by our device.
+ * Thus, we cap the maximum in the rare cases where the CPU count also
+ * exceeds our vector limit
+ */
+ vectors = min_t(int, vectors, hw->mac.max_msix_vectors);
+
+ /* We want a minimum of two MSI-X vectors for (1) a TxQ[0] + RxQ[0]
+ * handler, and (2) an Other (Link Status Change, etc.) handler.
*/
+ vector_threshold = MIN_MSIX_COUNT;
+
adapter->msix_entries = kcalloc(vectors,
sizeof(struct msix_entry),
GFP_KERNEL);
**/
static void ixgbe_set_interrupt_capability(struct ixgbe_adapter *adapter)
{
- struct ixgbe_hw *hw = &adapter->hw;
- int v_budget, err;
-
- /*
- * It's easy to be greedy for MSI-X vectors, but it really
- * doesn't do us much good if we have a lot more vectors
- * than CPU's. So let's be conservative and only ask for
- * (roughly) the same number of vectors as there are CPU's.
- * The default is to use pairs of vectors.
- */
- v_budget = max(adapter->num_rx_queues, adapter->num_tx_queues);
- v_budget = min_t(int, v_budget, num_online_cpus());
- v_budget += NON_Q_VECTORS;
-
- /*
- * At the same time, hardware can only support a maximum of
- * hw.mac->max_msix_vectors vectors. With features
- * such as RSS and VMDq, we can easily surpass the number of Rx and Tx
- * descriptor queues supported by our device. Thus, we cap it off in
- * those rare cases where the cpu count also exceeds our vector limit.
- */
- v_budget = min_t(int, v_budget, hw->mac.max_msix_vectors);
+ int err;
- /* A failure in MSI-X entry allocation isn't fatal, but it does
- * mean we disable MSI-X capabilities of the adapter. */
- if (!ixgbe_acquire_msix_vectors(adapter, v_budget))
+ /* We will try to get MSI-X interrupts first */
+ if (!ixgbe_acquire_msix_vectors(adapter))
return;
/* At this point, we do not have MSI-X capabilities. We need to