Module Name: src
Committed By: knakahara
Date: Mon Jan 18 09:09:04 UTC 2021
Modified Files:
src/sys/dev/pci/ixgbe: ix_txrx.c
Log Message:
Fix ixg(4) Rx interrupt stall when Rx buffers are exhausted.
Current ixgbe_rxeof() implementation calls ixgbe_refresh_mbufs()(and
ixgbe_getjcl()) after ixgbe_rx_input()(and if_percpuq_enqueue()).
And ixg(4) uses its own m_ext structure. That causes Rx interrupt
stall when Rx buffers are exhausted. e.g. TCP iperf3 with large
windows size. Furthermore, Rx descriptor problem has occurred
after stoppping the load.
To fix that problem, ixgbe_rxeof() must call ixgbe_getjcl() before
ixgbe_rx_input(), and must discard the new packet when ixgbe_getjcl()
fails.
By the way, ixg(4) should use MCLGET() instead of own m_ext structure.
ok'ed by msaitoh@n.o, thanks.
To generate a diff of this commit:
cvs rdiff -u -r1.63 -r1.64 src/sys/dev/pci/ixgbe/ix_txrx.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/pci/ixgbe/ix_txrx.c
diff -u src/sys/dev/pci/ixgbe/ix_txrx.c:1.63 src/sys/dev/pci/ixgbe/ix_txrx.c:1.64
--- src/sys/dev/pci/ixgbe/ix_txrx.c:1.63 Fri Apr 17 02:21:25 2020
+++ src/sys/dev/pci/ixgbe/ix_txrx.c Mon Jan 18 09:09:04 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: ix_txrx.c,v 1.63 2020/04/17 02:21:25 msaitoh Exp $ */
+/* $NetBSD: ix_txrx.c,v 1.64 2021/01/18 09:09:04 knakahara Exp $ */
/******************************************************************************
@@ -1818,6 +1818,7 @@ ixgbe_rxeof(struct ix_queue *que)
for (i = rxr->next_to_check; count != 0;) {
struct mbuf *sendmp, *mp;
+ struct mbuf *newmp;
u32 rsc, ptype;
u16 len;
u16 vtag = 0;
@@ -1860,6 +1861,15 @@ ixgbe_rxeof(struct ix_queue *que)
goto next_desc;
}
+ /* pre-alloc new mbuf */
+ newmp = ixgbe_getjcl(&rxr->jcl_head, M_NOWAIT, MT_DATA, M_PKTHDR,
+ rxr->mbuf_sz);
+ if (newmp == NULL) {
+ rxr->rx_discarded.ev_count++;
+ ixgbe_rx_discard(rxr, i);
+ goto next_desc;
+ }
+
bus_dmamap_sync(rxr->ptag->dt_dmat, rbuf->pmap, 0,
rbuf->buf->m_pkthdr.len, BUS_DMASYNC_POSTREAD);
@@ -1908,7 +1918,8 @@ ixgbe_rxeof(struct ix_queue *que)
*/
sendmp = rbuf->fmp;
if (sendmp != NULL) { /* secondary frag */
- rbuf->buf = rbuf->fmp = NULL;
+ rbuf->buf = newmp;
+ rbuf->fmp = NULL;
mp->m_flags &= ~M_PKTHDR;
sendmp->m_pkthdr.len += mp->m_len;
} else {
@@ -1927,10 +1938,13 @@ ixgbe_rxeof(struct ix_queue *que)
sendmp->m_len = len;
rxr->rx_copies.ev_count++;
rbuf->flags |= IXGBE_RX_COPY;
+
+ m_freem(newmp);
}
}
if (sendmp == NULL) {
- rbuf->buf = rbuf->fmp = NULL;
+ rbuf->buf = newmp;
+ rbuf->fmp = NULL;
sendmp = mp;
}
