As tx mbuf is not set for some advanced descriptors, if there is no
mbuf checking before rte_pktmbuf_free_seg() function be called on
the process of tx done clean up, that will cause a segfault. So add
a NULL pointer check to fix it.
Bugzilla ID: 501
Fixes: 8d907d2b79f7 (net/igb: free consumed Tx buffers on demand)
Signed-off-by: Jeff Guo <jia....@intel.com>
---
drivers/net/e1000/igb_rxtx.c | 170 +++++++++++++++++------------------
1 file changed, 82 insertions(+), 88 deletions(-)
diff --git a/drivers/net/e1000/igb_rxtx.c b/drivers/net/e1000/igb_rxtx.c
index 5717cdb70..115a723e4 100644
--- a/drivers/net/e1000/igb_rxtx.c
+++ b/drivers/net/e1000/igb_rxtx.c
@@ -1295,113 +1295,107 @@ igb_tx_done_cleanup(struct igb_tx_queue *txq,
uint32_t free_cnt)
uint16_t tx_id; /* Current segment being processed. */
uint16_t tx_last; /* Last segment in the current packet. */
uint16_t tx_next; /* First segment of the next packet. */
- int count;
+ int count = 0;
- if (txq != NULL) {
- count = 0;
- sw_ring = txq->sw_ring;
- txr = txq->tx_ring;
+ if (!txq)
+ return = -ENODEV;
- /*
- * tx_tail is the last sent packet on the sw_ring. Goto the end
- * of that packet (the last segment in the packet chain) and
- * then the next segment will be the start of the oldest segment
- * in the sw_ring. This is the first packet that will be
- * attempted to be freed.
- */
+ sw_ring = txq->sw_ring;
+ txr = txq->tx_ring;
- /* Get last segment in most recently added packet. */
- tx_first = sw_ring[txq->tx_tail].last_id;
+ /* tx_tail is the last sent packet on the sw_ring. Goto the end
+ * of that packet (the last segment in the packet chain) and
+ * then the next segment will be the start of the oldest segment
+ * in the sw_ring. This is the first packet that will be
+ * attempted to be freed.
+ */
- /* Get the next segment, which is the oldest segment in ring. */
- tx_first = sw_ring[tx_first].next_id;
+ /* Get last segment in most recently added packet. */
+ tx_first = sw_ring[txq->tx_tail].last_id;
- /* Set the current index to the first. */
- tx_id = tx_first;
+ /* Get the next segment, which is the oldest segment in ring. */
+ tx_first = sw_ring[tx_first].next_id;
- /*
- * Loop through each packet. For each packet, verify that an
- * mbuf exists and that the last segment is free. If so, free
- * it and move on.
- */
- while (1) {
- tx_last = sw_ring[tx_id].last_id;
-
- if (sw_ring[tx_last].mbuf) {
- if (txr[tx_last].wb.status &
- E1000_TXD_STAT_DD) {
- /*
- * Increment the number of packets
- * freed.
- */
- count++;
-
- /* Get the start of the next packet. */
- tx_next = sw_ring[tx_last].next_id;
-
- /*
- * Loop through all segments in a
- * packet.
- */
- do {
-
rte_pktmbuf_free_seg(sw_ring[tx_id].mbuf);
+ /* Set the current index to the first. */
+ tx_id = tx_first;
+
+ /* Loop through each packet. For each packet, verify that an
+ * mbuf exists and that the last segment is free. If so, free
+ * it and move on.
+ */
+ while (1) {
+ tx_last = sw_ring[tx_id].last_id;
+
+ if (sw_ring[tx_last].mbuf) {
+ if (txr[tx_last].wb.status &
+ E1000_TXD_STAT_DD) {
+ /* Increment the number of packets
+ * freed.
+ */
+ count++;
+
+ /* Get the start of the next packet. */
+ tx_next = sw_ring[tx_last].next_id;
+
+ /* Loop through all segments in a
+ * packet.
+ */
+ do {
+ if (sw_ring[tx_id].mbuf) {
+ rte_pktmbuf_free_seg(
+ sw_ring[tx_id].mbuf);
sw_ring[tx_id].mbuf = NULL;
sw_ring[tx_id].last_id = tx_id;
+ }
- /* Move to next segemnt. */
- tx_id = sw_ring[tx_id].next_id;
+ /* Move to next segemnt. */
+ tx_id = sw_ring[tx_id].next_id;
- } while (tx_id != tx_next);
+ } while (tx_id != tx_next);
- if (unlikely(count == (int)free_cnt))
- break;
- } else
- /*
- * mbuf still in use, nothing left to
- * free.
- */
+ if (unlikely(count == (int)free_cnt))
break;
} else {
- /*
- * There are multiple reasons to be here:
- * 1) All the packets on the ring have been
- * freed - tx_id is equal to tx_first
- * and some packets have been freed.
- * - Done, exit
- * 2) Interfaces has not sent a rings worth of
- * packets yet, so the segment after tail is
- * still empty. Or a previous call to this
- * function freed some of the segments but
- * not all so there is a hole in the list.
- * Hopefully this is a rare case.
- * - Walk the list and find the next mbuf. If
- * there isn't one, then done.
+ /* mbuf still in use, nothing left to
+ * free.
*/
- if (likely((tx_id == tx_first) && (count != 0)))
- break;
+ break;
+ }
+ } else {
+ /* There are multiple reasons to be here:
+ * 1) All the packets on the ring have been
+ * freed - tx_id is equal to tx_first
+ * and some packets have been freed.
+ * - Done, exit
+ * 2) Interfaces has not sent a rings worth of
+ * packets yet, so the segment after tail is
+ * still empty. Or a previous call to this
+ * function freed some of the segments but
+ * not all so there is a hole in the list.
+ * Hopefully this is a rare case.
+ * - Walk the list and find the next mbuf. If
+ * there isn't one, then done.
+ */
+ if (likely(tx_id == tx_first && count != 0))
+ break;
- /*
- * Walk the list and find the next mbuf, if any.
- */
- do {
- /* Move to next segemnt. */
- tx_id = sw_ring[tx_id].next_id;
+ /* Walk the list and find the next mbuf, if any. */
+ do {
+ /* Move to next segemnt. */
+ tx_id = sw_ring[tx_id].next_id;
- if (sw_ring[tx_id].mbuf)
- break;
+ if (sw_ring[tx_id].mbuf)
+ break;
- } while (tx_id != tx_first);
+ } while (tx_id != tx_first);
- /*
- * Determine why previous loop bailed. If there
- * is not an mbuf, done.
- */
- if (sw_ring[tx_id].mbuf == NULL)
- break;
- }
+ /* Determine why previous loop bailed. If there
+ * is not an mbuf, done.
+ */
+ if (!sw_ring[tx_id].mbuf)
+ break;
}
- } else
- count = -ENODEV;
+ }
return count;
}
--
2.20.1
