PERFORCE change 125097 for review

[Kip Macy]

http://perforce.freebsd.org/chv.cgi?CH=125097

Change 125097 by kmacy at kmacy_home:ethng on 2007/08/13 04:31:46

	move to using lock embedded in mbuf_ring for protecting producer side

Affected files ...

.. //depot/projects/ethng/src/sys/dev/cxgb/cxgb_multiq.c#6 edit
.. //depot/projects/ethng/src/sys/dev/cxgb/cxgb_osdep.h#3 edit
.. //depot/projects/ethng/src/sys/dev/cxgb/cxgb_sge.c#9 edit

Differences ...

==== //depot/projects/ethng/src/sys/dev/cxgb/cxgb_multiq.c#6 (text+ko) ====

@@ -113,43 +113,36 @@
 	struct sge_txq *txq;
 	struct mbuf_ring *mr;
 	struct mbuf_head *mbq;
+	int prod, cons, mask;
 	int err = 0;
 	
 	if (qs->qs_flags & QS_EXITING) {
 		m_freem_vec(m);
 		return (ENXIO);
 	}
-
 	txq = &qs->txq[TXQ_ETH];
 	
 	DPRINTF("enqueueing packet to cpuid=%d\n", qs->qs_cpuid);
 
 	mbq = &txq->sendq;
-	if (curcpu == qs->qs_cpuid) {
-		critical_enter();
-		mbufq_tail(mbq, m);
-		critical_exit();
+	
+	mr = &txq->txq_mr;
+	mtx_lock(&mr->mr_lock);
+	cons = mr->mr_cons;
+	prod = mr->mr_prod;
+	mask = mr->mr_size - 1;
+	if (((prod + 1) & mask) != cons) {
+		mr->mr_ring[prod] = m;
+		mr->mr_prod = (prod + 1) & mask;
 	} else {
-		int prod, cons, mask;
-
-		mr = &txq->txq_mr;
-		mtx_lock(&txq->lock);
-		cons = mr->mr_cons;
-		prod = mr->mr_prod;
-		mask = mr->mr_size - 1;
-		if (((prod + 1) & mask) != cons) {
-			mr->mr_ring[prod] = m;
-			mr->mr_prod = (prod + 1) & mask;
-		} else {
-			txq->txq_drops++;
-			err = ENOBUFS;
-		}
-		mtx_unlock(&txq->lock);
-		if ((qs->txq[TXQ_ETH].flags & TXQ_TRANSMITTING) == 0)
-			wakeup(qs);
-		if (err) 
-			m_freem(m);
+		txq->txq_drops++;
+		err = ENOBUFS;
 	}
+	mtx_unlock(&mr->mr_lock);
+	if ((qs->txq[TXQ_ETH].flags & TXQ_TRANSMITTING) == 0)
+		wakeup(qs);
+	if (err) 
+		m_freem(m);
 
 	return (err);
 }
@@ -362,7 +355,6 @@
 		return (ENOBUFS); 
 	}
 	
-	critical_enter();
 	cons = mr->mr_cons;
 	prod = mr->mr_prod;
 	while (cons != prod) {
@@ -375,7 +367,6 @@
 		mbufq_tail(mbq, imm);
 
 	*complete = ((mbufq_size(mbq) > TX_WR_SIZE_MAX) || (mbufq_len(mbq) >= TX_WR_COUNT_MAX));
-	critical_exit();
 
 	return (err);
 }

==== //depot/projects/ethng/src/sys/dev/cxgb/cxgb_osdep.h#3 (text+ko) ====

@@ -36,6 +36,9 @@
 #include <sys/endian.h>
 #include <sys/bus.h>
 
+#include <sys/lock.h>
+#include <sys/mutex.h>
+
 #include <dev/mii/mii.h>
 
 #ifdef CONFIG_DEFINED
@@ -57,6 +60,7 @@
 	volatile uint32_t mr_cons;
 	volatile uint32_t mr_prod;
 	int               mr_size;
+	struct mtx        mr_lock;
 };
 
 #define PANIC_IF(exp) do {                  \

==== //depot/projects/ethng/src/sys/dev/cxgb/cxgb_sge.c#9 (text+ko) ====

@@ -1540,9 +1540,10 @@
 	int i;
 
        for (i = 0; i < SGE_TXQ_PER_SET; i++) 
-	       if (q->txq[i].txq_mr.mr_ring != NULL)
+	       if (q->txq[i].txq_mr.mr_ring != NULL) {
 		       free(q->txq[i].txq_mr.mr_ring, M_DEVBUF);
-
+		       mtx_destroy(&q->txq[i].txq_mr.mr_lock);
+	       }
        for (i = 0; i < SGE_RXQ_PER_SET; ++i) {
 		if (q->fl[i].desc) {
 			mtx_lock(&sc->sge.reg_lock);
@@ -2070,6 +2071,7 @@
 		}
 		q->txq[i].txq_mr.mr_prod = q->txq[i].txq_mr.mr_cons = 0;
 		q->txq[i].txq_mr.mr_size = cxgb_txq_mbuf_ring_size;
+		mtx_init(&q->txq[i].txq_mr.mr_lock, "txq mbuf ring", NULL, MTX_DEF);
 	}
 	
 	init_qset_cntxt(q, id);