[openib-general] [PATCH 3/7] IB/ipath - performance improvements via mmap of queues

[Roland Dreier]

I applied this, but I'm wondering if this:

 > +int ipath_resize_cq(struct ibv_cq *ibcq, int cqe)
 >  {
 > +	struct ipath_cq		       *cq = to_icq(ibcq);
 > +	struct ibv_resize_cq		cmd;
 > +	struct ipath_resize_cq_resp	resp;
 > +	size_t				size;
 > +	int				ret;
 > +
 > +	pthread_spin_lock(&cq->lock);
 > +	/* Save the old size so we can unmmap the queue. */
 > +	size = sizeof(struct ipath_cq_wc) +
 > +		(sizeof(struct ipath_wc) * cq->ibv_cq.cqe);
 > +	ret = ibv_cmd_resize_cq(ibcq, cqe, &cmd, sizeof cmd,
 > +				&resp.ibv_resp, sizeof resp);
 > +	if (ret) {
 > +		pthread_spin_unlock(&cq->lock);
 > +		return ret;
 > +	}
 > +	(void) munmap(cq->queue, size);
 > +	size = sizeof(struct ipath_cq_wc) +
 > +		(sizeof(struct ipath_wc) * cq->ibv_cq.cqe);
 > +	cq->queue = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED,
 > +			 ibcq->context->cmd_fd, resp.offset);
 > +	ret = errno;
 > +	pthread_spin_unlock(&cq->lock);
 > +	if ((void *) cq->queue == MAP_FAILED)
 > +		return ret;
 > +	return 0;
 > +}

works against an old kernel driver.  It seems you do have this:

 > +	if (dev->abi_version == 1) {
 > +		context->ibv_ctx.ops.poll_cq       = ibv_cmd_poll_cq;
 > +		context->ibv_ctx.ops.post_srq_recv = ibv_cmd_post_srq_recv;
 > +		context->ibv_ctx.ops.post_recv     = ibv_cmd_post_recv;
 > +	}

so I guess you're just ignoring the failure of mmap() or something?

 - R.