Provide a set of inline functions to manage simple mbuf(9) queues, based

on queue(3)'s STAILQ.  Utilize them in cxgb(4) and Xen, deleting home
grown implementations.

Sponsored by:	Netflix
Sponsored by:	Nginx, Inc.

2 files changed, 10 insertions, 134 deletions

diff --git a/sys/dev/xen/netfront/mbufq.h b/sys/dev/xen/netfront/mbufq.h
deleted file mode 100644
index 0d6c60430ae6..000000000000
--- a/sys/dev/xen/netfront/mbufq.h
+++ /dev/null
@@ -1,123 +0,0 @@
-/**************************************************************************
-
-Copyright (c) 2007, Chelsio Inc.
-All rights reserved.
-
-Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions are met:
-
- 1. Redistributions of source code must retain the above copyright notice,
-    this list of conditions and the following disclaimer.
-
- 2. Neither the name of the Chelsio Corporation nor the names of its
-    contributors may be used to endorse or promote products derived from
-    this software without specific prior written permission.
-
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
-AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
-ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
-LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
-CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
-SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
-INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
-CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
-ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
-POSSIBILITY OF SUCH DAMAGE.
-
-$FreeBSD$
-
-***************************************************************************/
-
-#ifndef CXGB_MBUFQ_H_
-#define CXGB_MBUFQ_H_
-
-struct mbuf_head {
-	struct mbuf *head;
-	struct mbuf *tail;
-	uint32_t     qlen;
-	uint32_t     qsize;
-	struct mtx   lock;
-};
-
-static __inline void
-mbufq_init(struct mbuf_head *l)
-{
-	l->head = l->tail = NULL;
-	l->qlen = l->qsize = 0;
-}
-
-static __inline int
-mbufq_empty(struct mbuf_head *l)
-{
-	return (l->head == NULL);
-}
-
-static __inline int
-mbufq_len(struct mbuf_head *l)
-{
-	return (l->qlen);
-}
-
-static __inline int
-mbufq_size(struct mbuf_head *l)
-{
-	return (l->qsize);
-}
-
-static __inline int
-mbufq_head_size(struct mbuf_head *l)
-{
-	return (l->head ? l->head->m_pkthdr.len : 0);
-}
-
-static __inline void
-mbufq_tail(struct mbuf_head *l, struct mbuf *m)
-{
-	l->qlen++;
-	if (l->head == NULL)
-		l->head = m;
-	else
-		l->tail->m_nextpkt = m;
-	l->tail = m;
-	l->qsize += m->m_pkthdr.len;
-}
-
-static __inline struct mbuf *
-mbufq_dequeue(struct mbuf_head *l)
-{
-	struct mbuf *m;
-
-	m = l->head;
-	if (m) {
-		if (m == l->tail) 
-			l->head = l->tail = NULL;
-		else
-			l->head = m->m_nextpkt;
-		m->m_nextpkt = NULL;
-		l->qlen--;
-		l->qsize -= m->m_pkthdr.len;
-	}
-
-	return (m);
-}
-
-static __inline struct mbuf *
-mbufq_peek(struct mbuf_head *l)
-{
-	return (l->head);
-}
-
-static __inline void
-mbufq_append(struct mbuf_head *a, struct mbuf_head *b)
-{
-	if (a->tail) 
-		a->tail->m_nextpkt = b->head;
-	if (b->tail)
-		a->tail = b->tail;
-	a->qlen += b->qlen;
-	a->qsize += b->qsize;
-	
-	
-}
-#endif  /* CXGB_MBUFQ_H_ */
diff --git a/sys/dev/xen/netfront/netfront.c b/sys/dev/xen/netfront/netfront.c
index 8f401ac1ad96..b97af6239ce3 100644
--- a/sys/dev/xen/netfront/netfront.c
+++ b/sys/dev/xen/netfront/netfront.c
@@ -33,6 +33,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/sockio.h>
+#include <sys/limits.h>
 #include <sys/mbuf.h>
 #include <sys/malloc.h>
 #include <sys/module.h>
@@ -87,8 +88,6 @@ __FBSDID("$FreeBSD$");
 
 #include <machine/xen/xenvar.h>
 
-#include <dev/xen/netfront/mbufq.h>
-
 #include "xenbus_if.h"
 
 /* Features supported by all backends.  TSO and LRO can be negotiated */
@@ -277,7 +276,7 @@ struct netfront_info {
 	int			rx_ring_ref;
 	uint8_t			mac[ETHER_ADDR_LEN];
 	struct xn_chain_data	xn_cdata;	/* mbufs */
-	struct mbuf_head	xn_rx_batch;	/* head of the batch queue */
+	struct mbufq		xn_rx_batch;	/* batch queue */
 
 	int			xn_if_flags;
 	struct callout	        xn_stat_ch;
@@ -837,7 +836,7 @@ no_mbuf:
 		m_new->m_len = m_new->m_pkthdr.len = MJUMPAGESIZE;
 		
 		/* queue the mbufs allocated */
-		mbufq_tail(&sc->xn_rx_batch, m_new);
+		(void )mbufq_enqueue(&sc->xn_rx_batch, m_new);
 	}
 	
 	/*
@@ -973,7 +972,7 @@ xn_rxeof(struct netfront_info *np)
 	RING_IDX i, rp;
 	multicall_entry_t *mcl;
 	struct mbuf *m;
-	struct mbuf_head rxq, errq;
+	struct mbufq rxq, errq;
 	int err, pages_flipped = 0, work_to_do;
 
 	do {
@@ -981,8 +980,9 @@ xn_rxeof(struct netfront_info *np)
 		if (!netfront_carrier_ok(np))
 			return;
 
-		mbufq_init(&errq);
-		mbufq_init(&rxq);
+		/* XXX: there should be some sane limit. */
+		mbufq_init(&errq, INT_MAX);
+		mbufq_init(&rxq, INT_MAX);
 
 		ifp = np->xn_ifp;
 	
@@ -1000,7 +1000,7 @@ xn_rxeof(struct netfront_info *np)
 
 			if (__predict_false(err)) {
 				if (m)
-					mbufq_tail(&errq, m);
+					(void )mbufq_enqueue(&errq, m);
 				np->stats.rx_errors++;
 				continue;
 			}
@@ -1022,7 +1022,7 @@ xn_rxeof(struct netfront_info *np)
 			np->stats.rx_packets++;
 			np->stats.rx_bytes += m->m_pkthdr.len;
 
-			mbufq_tail(&rxq, m);
+			(void )mbufq_enqueue(&rxq, m);
 			np->rx.rsp_cons = i;
 		}
 
@@ -1046,8 +1046,7 @@ xn_rxeof(struct netfront_info *np)
 			}
 		}
 	
-		while ((m = mbufq_dequeue(&errq)))
-			m_freem(m);
+		mbufq_drain(&errq);
 
 		/* 
 		 * Process all the mbufs after the remapping is complete.