Function test_burst_capacity

dpdk/app/test/test_dmadev.c:762–824

}

static int
test_burst_capacity(int16_t dev_id, uint16_t vchan)
{
#define CAP_TEST_BURST_SIZE	64
	const int ring_space = rte_dma_burst_capacity(dev_id, vchan);
	struct rte_mbuf *src, *dst;
	int i, j, iter;
	int cap, ret;
	bool dma_err;

	src = rte_pktmbuf_alloc(pool);
	dst = rte_pktmbuf_alloc(pool);

	/* to test capacity, we enqueue elements and check capacity is reduced
	 * by one each time - rebaselining the expected value after each burst
	 * as the capacity is only for a burst. We enqueue multiple bursts to
	 * fill up half the ring, before emptying it again. We do this multiple
	 * times to ensure that we get to test scenarios where we get ring
	 * wrap-around and wrap-around of the ids returned (at UINT16_MAX).
	 */
	for (iter = 0; iter < 2 * (((int)UINT16_MAX + 1) / ring_space); iter++) {
		for (i = 0; i < (ring_space / (2 * CAP_TEST_BURST_SIZE)) + 1; i++) {
			cap = rte_dma_burst_capacity(dev_id, vchan);

			for (j = 0; j < CAP_TEST_BURST_SIZE; j++) {
				ret = rte_dma_copy(dev_id, vchan, rte_pktmbuf_iova(src),
						rte_pktmbuf_iova(dst), COPY_LEN, 0);
				if (ret < 0)
					ERR_RETURN("Error with rte_dmadev_copy\n");

				if (rte_dma_burst_capacity(dev_id, vchan) != cap - (j + 1))
					ERR_RETURN("Error, ring capacity did not change as expected\n");
			}
			if (rte_dma_submit(dev_id, vchan) < 0)
				ERR_RETURN("Error, failed to submit burst\n");

			if (cap < rte_dma_burst_capacity(dev_id, vchan))
				ERR_RETURN("Error, avail ring capacity has gone up, not down\n");
		}
		await_hw(dev_id, vchan);

		for (i = 0; i < (ring_space / (2 * CAP_TEST_BURST_SIZE)) + 1; i++) {
			ret = rte_dma_completed(dev_id, vchan,
					CAP_TEST_BURST_SIZE, NULL, &dma_err);
			if (ret != CAP_TEST_BURST_SIZE || dma_err) {
				enum rte_dma_status_code status;

				rte_dma_completed_status(dev_id, vchan, 1, NULL, &status);
				ERR_RETURN("Error with rte_dmadev_completed, %u [expected: %u], dma_err = %d, i = %u, iter = %u, status = %u\n",
						ret, CAP_TEST_BURST_SIZE, dma_err, i, iter, status);
			}
		}
		cap = rte_dma_burst_capacity(dev_id, vchan);
		if (cap != ring_space)
			ERR_RETURN("Error, ring capacity has not reset to original value, got %u, expected %u\n",
					cap, ring_space);
	}