Make xl use m_getcl() to allocate an mbuf and a cluster in one shot,

as opposed to one after the other.  This is faster in both -CURRENT
and -STABLE.  Additionally, there is less code duplication for
error-checking.

One thing to note is that this code seems to return(1) when no buffers
are available; perhaps ENOBUFS should be the correct return value?

Partially submitted & tested by: Hiten Pandya <hiten@unixdaemons.com>
MFC after: 1 week

1 files changed, 5 insertions, 19 deletions

diff --git a/sys/pci/if_xl.c b/sys/pci/if_xl.c
index 7920792..cc4c6d5 100644
--- a/sys/pci/if_xl.c
+++ b/sys/pci/if_xl.c
@@ -1939,16 +1939,10 @@ xl_newbuf(sc, c)
 	int			error;
 	u_int32_t		baddr;
 
-	MGETHDR(m_new, M_DONTWAIT, MT_DATA);
+	m_new = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
 	if (m_new == NULL)
 		return(ENOBUFS);
 
-	MCLGET(m_new, M_DONTWAIT);
-	if (!(m_new->m_flags & M_EXT)) {
-		m_freem(m_new);
-		return(ENOBUFS);
-	}
-
 	m_new->m_len = m_new->m_pkthdr.len = MCLBYTES;
 
 	/* Force longword alignment for packet payload. */
@@ -2441,24 +2435,16 @@ xl_encap(sc, c, m_head)
 	 * and would waste cycles.
 	 */
 	if (error) {
-		struct mbuf		*m_new = NULL;
+		struct mbuf		*m_new;
 
-		MGETHDR(m_new, M_DONTWAIT, MT_DATA);
+		m_new = m_head->m_pkthdr.len > MHLEN ?
+		    m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR) :
+		    m_get(M_DONTWAIT, MT_DATA);
 		if (m_new == NULL) {
 			m_freem(m_head);
 			printf("xl%d: no memory for tx list\n", sc->xl_unit);
 			return(1);
 		}
-		if (m_head->m_pkthdr.len > MHLEN) {
-			MCLGET(m_new, M_DONTWAIT);
-			if (!(m_new->m_flags & M_EXT)) {
-				m_freem(m_new);
-				m_freem(m_head);
-				printf("xl%d: no memory for tx list\n",
-						sc->xl_unit);
-				return(1);
-			}
-		}
 		m_copydata(m_head, 0, m_head->m_pkthdr.len,	
 					mtod(m_new, caddr_t));
 		m_new->m_pkthdr.len = m_new->m_len = m_head->m_pkthdr.len;