[PATCH] IB/ipath: rC receive interrupt performance changes
This patch separates QP state used for sending and receiving RC packets so the
processing in the receive interrupt handler can be done mostly without locks
being held. ACK packets are now sent without requiring synchronization with
the send tasklet.
Signed-off-by: Ralph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: Bryan O'Sullivan <bryan.osullivan@qlogic.com>
Cc: "Michael S. Tsirkin" <mst@mellanox.co.il>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/infiniband/hw/ipath/ipath_qp.c b/drivers/infiniband/hw/ipath/ipath_qp.c
index 83b9a6a..68f0151 100644
--- a/drivers/infiniband/hw/ipath/ipath_qp.c
+++ b/drivers/infiniband/hw/ipath/ipath_qp.c
@@ -333,10 +333,11 @@
qp->remote_qpn = 0;
qp->qkey = 0;
qp->qp_access_flags = 0;
+ clear_bit(IPATH_S_BUSY, &qp->s_flags);
qp->s_hdrwords = 0;
qp->s_psn = 0;
qp->r_psn = 0;
- atomic_set(&qp->msn, 0);
+ qp->r_msn = 0;
if (qp->ibqp.qp_type == IB_QPT_RC) {
qp->s_state = IB_OPCODE_RC_SEND_LAST;
qp->r_state = IB_OPCODE_RC_SEND_LAST;
@@ -345,7 +346,8 @@
qp->r_state = IB_OPCODE_UC_SEND_LAST;
}
qp->s_ack_state = IB_OPCODE_RC_ACKNOWLEDGE;
- qp->s_nak_state = 0;
+ qp->r_ack_state = IB_OPCODE_RC_ACKNOWLEDGE;
+ qp->r_nak_state = 0;
qp->s_rnr_timeout = 0;
qp->s_head = 0;
qp->s_tail = 0;
@@ -363,10 +365,10 @@
* @qp: the QP to put into an error state
*
* Flushes both send and receive work queues.
- * QP r_rq.lock and s_lock should be held.
+ * QP s_lock should be held and interrupts disabled.
*/
-static void ipath_error_qp(struct ipath_qp *qp)
+void ipath_error_qp(struct ipath_qp *qp)
{
struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
struct ib_wc wc;
@@ -409,12 +411,14 @@
qp->s_ack_state = IB_OPCODE_RC_ACKNOWLEDGE;
wc.opcode = IB_WC_RECV;
+ spin_lock(&qp->r_rq.lock);
while (qp->r_rq.tail != qp->r_rq.head) {
wc.wr_id = get_rwqe_ptr(&qp->r_rq, qp->r_rq.tail)->wr_id;
if (++qp->r_rq.tail >= qp->r_rq.size)
qp->r_rq.tail = 0;
ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
}
+ spin_unlock(&qp->r_rq.lock);
}
/**
@@ -434,8 +438,7 @@
unsigned long flags;
int ret;
- spin_lock_irqsave(&qp->r_rq.lock, flags);
- spin_lock(&qp->s_lock);
+ spin_lock_irqsave(&qp->s_lock, flags);
cur_state = attr_mask & IB_QP_CUR_STATE ?
attr->cur_qp_state : qp->state;
@@ -506,31 +509,19 @@
}
if (attr_mask & IB_QP_MIN_RNR_TIMER)
- qp->s_min_rnr_timer = attr->min_rnr_timer;
+ qp->r_min_rnr_timer = attr->min_rnr_timer;
if (attr_mask & IB_QP_QKEY)
qp->qkey = attr->qkey;
qp->state = new_state;
- spin_unlock(&qp->s_lock);
- spin_unlock_irqrestore(&qp->r_rq.lock, flags);
+ spin_unlock_irqrestore(&qp->s_lock, flags);
- /*
- * If QP1 changed to the RTS state, try to move to the link to INIT
- * even if it was ACTIVE so the SM will reinitialize the SMA's
- * state.
- */
- if (qp->ibqp.qp_num == 1 && new_state == IB_QPS_RTS) {
- struct ipath_ibdev *dev = to_idev(ibqp->device);
-
- ipath_layer_set_linkstate(dev->dd, IPATH_IB_LINKDOWN);
- }
ret = 0;
goto bail;
inval:
- spin_unlock(&qp->s_lock);
- spin_unlock_irqrestore(&qp->r_rq.lock, flags);
+ spin_unlock_irqrestore(&qp->s_lock, flags);
ret = -EINVAL;
bail:
@@ -564,7 +555,7 @@
attr->sq_draining = 0;
attr->max_rd_atomic = 1;
attr->max_dest_rd_atomic = 1;
- attr->min_rnr_timer = qp->s_min_rnr_timer;
+ attr->min_rnr_timer = qp->r_min_rnr_timer;
attr->port_num = 1;
attr->timeout = 0;
attr->retry_cnt = qp->s_retry_cnt;
@@ -591,16 +582,12 @@
* @qp: the queue pair to compute the AETH for
*
* Returns the AETH.
- *
- * The QP s_lock should be held.
*/
__be32 ipath_compute_aeth(struct ipath_qp *qp)
{
- u32 aeth = atomic_read(&qp->msn) & IPS_MSN_MASK;
+ u32 aeth = qp->r_msn & IPS_MSN_MASK;
- if (qp->s_nak_state) {
- aeth |= qp->s_nak_state << IPS_AETH_CREDIT_SHIFT;
- } else if (qp->ibqp.srq) {
+ if (qp->ibqp.srq) {
/*
* Shared receive queues don't generate credits.
* Set the credit field to the invalid value.