@@ -143,7 +143,37 @@ Performing Data Copies
~~~~~~~~~~~~~~~~~~~~~~~
Refer to the :ref:`Enqueue / Dequeue APIs <dmadev_enqueue_dequeue>` section of the dmadev library
-documentation for details on operation enqueue and submission API usage.
+documentation for details on operation enqueue, submission and completion API usage.
It is expected that, for efficiency reasons, a burst of operations will be enqueued to the
device via multiple enqueue calls between calls to the ``rte_dma_submit()`` function.
+
+When gathering completions, ``rte_dma_completed()`` should be used, up until the point an error
+occurs in an operation. If an error was encountered, ``rte_dma_completed_status()`` must be used
+to kick the device off to continue processing operations and also to gather the status of each
+individual operations which is filled in to the ``status`` array provided as parameter by the
+application.
+
+The following status codes are supported by IDXD:
+
+* ``RTE_DMA_STATUS_SUCCESSFUL``: The operation was successful.
+* ``RTE_DMA_STATUS_INVALID_OPCODE``: The operation failed due to an invalid operation code.
+* ``RTE_DMA_STATUS_INVALID_LENGTH``: The operation failed due to an invalid data length.
+* ``RTE_DMA_STATUS_NOT_ATTEMPTED``: The operation was not attempted.
+* ``RTE_DMA_STATUS_ERROR_UNKNOWN``: The operation failed due to an unspecified error.
+
+The following code shows how to retrieve the number of successfully completed
+copies within a burst and then using ``rte_dma_completed_status()`` to check
+which operation failed and kick off the device to continue processing operations:
+
+.. code-block:: C
+
+ enum rte_dma_status_code status[COMP_BURST_SZ];
+ uint16_t count, idx, status_count;
+ bool error = 0;
+
+ count = rte_dma_completed(dev_id, vchan, COMP_BURST_SZ, &idx, &error);
+
+ if (error){
+ status_count = rte_dma_completed_status(dev_id, vchan, COMP_BURST_SZ, &idx, status);
+ }
@@ -141,6 +141,240 @@ idxd_submit(void *dev_private, uint16_t qid __rte_unused)
return 0;
}
+static enum rte_dma_status_code
+get_comp_status(struct idxd_completion *c)
+{
+ uint8_t st = c->status;
+ switch (st) {
+ /* successful descriptors are not written back normally */
+ case IDXD_COMP_STATUS_INCOMPLETE:
+ case IDXD_COMP_STATUS_SUCCESS:
+ return RTE_DMA_STATUS_SUCCESSFUL;
+ case IDXD_COMP_STATUS_INVALID_OPCODE:
+ return RTE_DMA_STATUS_INVALID_OPCODE;
+ case IDXD_COMP_STATUS_INVALID_SIZE:
+ return RTE_DMA_STATUS_INVALID_LENGTH;
+ case IDXD_COMP_STATUS_SKIPPED:
+ return RTE_DMA_STATUS_NOT_ATTEMPTED;
+ default:
+ return RTE_DMA_STATUS_ERROR_UNKNOWN;
+ }
+}
+
+static __rte_always_inline int
+batch_ok(struct idxd_dmadev *idxd, uint16_t max_ops, enum rte_dma_status_code *status)
+{
+ uint16_t ret;
+ uint8_t bstatus;
+
+ if (max_ops == 0)
+ return 0;
+
+ /* first check if there are any unreturned handles from last time */
+ if (idxd->ids_avail != idxd->ids_returned) {
+ ret = RTE_MIN((uint16_t)(idxd->ids_avail - idxd->ids_returned), max_ops);
+ idxd->ids_returned += ret;
+ if (status)
+ memset(status, RTE_DMA_STATUS_SUCCESSFUL, ret * sizeof(*status));
+ return ret;
+ }
+
+ if (idxd->batch_idx_read == idxd->batch_idx_write)
+ return 0;
+
+ bstatus = idxd->batch_comp_ring[idxd->batch_idx_read].status;
+ /* now check if next batch is complete and successful */
+ if (bstatus == IDXD_COMP_STATUS_SUCCESS) {
+ /* since the batch idx ring stores the start of each batch, pre-increment to lookup
+ * start of next batch.
+ */
+ if (++idxd->batch_idx_read > idxd->max_batches)
+ idxd->batch_idx_read = 0;
+ idxd->ids_avail = idxd->batch_idx_ring[idxd->batch_idx_read];
+
+ ret = RTE_MIN((uint16_t)(idxd->ids_avail - idxd->ids_returned), max_ops);
+ idxd->ids_returned += ret;
+ if (status)
+ memset(status, RTE_DMA_STATUS_SUCCESSFUL, ret * sizeof(*status));
+ return ret;
+ }
+ /* check if batch is incomplete */
+ else if (bstatus == IDXD_COMP_STATUS_INCOMPLETE)
+ return 0;
+
+ return -1; /* error case */
+}
+
+static inline uint16_t
+batch_completed(struct idxd_dmadev *idxd, uint16_t max_ops, bool *has_error)
+{
+ uint16_t i;
+ uint16_t b_start, b_end, next_batch;
+
+ int ret = batch_ok(idxd, max_ops, NULL);
+ if (ret >= 0)
+ return ret;
+
+ /* ERROR case, not successful, not incomplete */
+ /* Get the batch size, and special case size 1.
+ * once we identify the actual failure job, return other jobs, then update
+ * the batch ring indexes to make it look like the first job of the batch has failed.
+ * Subsequent calls here will always return zero packets, and the error must be cleared by
+ * calling the completed_status() function.
+ */
+ next_batch = (idxd->batch_idx_read + 1);
+ if (next_batch > idxd->max_batches)
+ next_batch = 0;
+ b_start = idxd->batch_idx_ring[idxd->batch_idx_read];
+ b_end = idxd->batch_idx_ring[next_batch];
+
+ if (b_end - b_start == 1) { /* not a batch */
+ *has_error = true;
+ return 0;
+ }
+
+ for (i = b_start; i < b_end; i++) {
+ struct idxd_completion *c = (void *)&idxd->desc_ring[i & idxd->desc_ring_mask];
+ if (c->status > IDXD_COMP_STATUS_SUCCESS) /* ignore incomplete(0) and success(1) */
+ break;
+ }
+ ret = RTE_MIN((uint16_t)(i - idxd->ids_returned), max_ops);
+ if (ret < max_ops)
+ *has_error = true; /* we got up to the point of error */
+ idxd->ids_avail = idxd->ids_returned += ret;
+
+ /* to ensure we can call twice and just return 0, set start of batch to where we finished */
+ idxd->batch_comp_ring[idxd->batch_idx_read].completed_size -= ret;
+ idxd->batch_idx_ring[idxd->batch_idx_read] += ret;
+ if (idxd->batch_idx_ring[next_batch] - idxd->batch_idx_ring[idxd->batch_idx_read] == 1) {
+ /* copy over the descriptor status to the batch ring as if no batch */
+ uint16_t d_idx = idxd->batch_idx_ring[idxd->batch_idx_read] & idxd->desc_ring_mask;
+ struct idxd_completion *desc_comp = (void *)&idxd->desc_ring[d_idx];
+ idxd->batch_comp_ring[idxd->batch_idx_read].status = desc_comp->status;
+ }
+
+ return ret;
+}
+
+static uint16_t
+batch_completed_status(struct idxd_dmadev *idxd, uint16_t max_ops, enum rte_dma_status_code *status)
+{
+ uint16_t next_batch;
+
+ int ret = batch_ok(idxd, max_ops, status);
+ if (ret >= 0)
+ return ret;
+
+ /* ERROR case, not successful, not incomplete */
+ /* Get the batch size, and special case size 1.
+ */
+ next_batch = (idxd->batch_idx_read + 1);
+ if (next_batch > idxd->max_batches)
+ next_batch = 0;
+ const uint16_t b_start = idxd->batch_idx_ring[idxd->batch_idx_read];
+ const uint16_t b_end = idxd->batch_idx_ring[next_batch];
+ const uint16_t b_len = b_end - b_start;
+ if (b_len == 1) {/* not a batch */
+ *status = get_comp_status(&idxd->batch_comp_ring[idxd->batch_idx_read]);
+ idxd->ids_avail++;
+ idxd->ids_returned++;
+ idxd->batch_idx_read = next_batch;
+ return 1;
+ }
+
+ /* not a single-element batch, need to process more.
+ * Scenarios:
+ * 1. max_ops >= batch_size - can fit everything, simple case
+ * - loop through completed ops and then add on any not-attempted ones
+ * 2. max_ops < batch_size - can't fit everything, more complex case
+ * - loop through completed/incomplete and stop when hit max_ops
+ * - adjust the batch descriptor to update where we stopped, with appropriate bcount
+ * - if bcount is to be exactly 1, update the batch descriptor as it will be treated as
+ * non-batch next time.
+ */
+ const uint16_t bcount = idxd->batch_comp_ring[idxd->batch_idx_read].completed_size;
+ for (ret = 0; ret < b_len && ret < max_ops; ret++) {
+ struct idxd_completion *c = (void *)
+ &idxd->desc_ring[(b_start + ret) & idxd->desc_ring_mask];
+ status[ret] = (ret < bcount) ? get_comp_status(c) : RTE_DMA_STATUS_NOT_ATTEMPTED;
+ }
+ idxd->ids_avail = idxd->ids_returned += ret;
+
+ /* everything fit */
+ if (ret == b_len) {
+ idxd->batch_idx_read = next_batch;
+ return ret;
+ }
+
+ /* set up for next time, update existing batch descriptor & start idx at batch_idx_read */
+ idxd->batch_idx_ring[idxd->batch_idx_read] += ret;
+ if (ret > bcount) {
+ /* we have only incomplete ones - set batch completed size to 0 */
+ struct idxd_completion *comp = &idxd->batch_comp_ring[idxd->batch_idx_read];
+ comp->completed_size = 0;
+ /* if there is only one descriptor left, job skipped so set flag appropriately */
+ if (b_len - ret == 1)
+ comp->status = IDXD_COMP_STATUS_SKIPPED;
+ } else {
+ struct idxd_completion *comp = &idxd->batch_comp_ring[idxd->batch_idx_read];
+ comp->completed_size -= ret;
+ /* if there is only one descriptor left, copy status info straight to desc */
+ if (comp->completed_size == 1) {
+ struct idxd_completion *c = (void *)
+ &idxd->desc_ring[(b_start + ret) & idxd->desc_ring_mask];
+ comp->status = c->status;
+ /* individual descs can be ok without writeback, but not batches */
+ if (comp->status == IDXD_COMP_STATUS_INCOMPLETE)
+ comp->status = IDXD_COMP_STATUS_SUCCESS;
+ } else if (bcount == b_len) {
+ /* check if we still have an error, and clear flag if not */
+ uint16_t i;
+ for (i = b_start + ret; i < b_end; i++) {
+ struct idxd_completion *c = (void *)
+ &idxd->desc_ring[i & idxd->desc_ring_mask];
+ if (c->status > IDXD_COMP_STATUS_SUCCESS)
+ break;
+ }
+ if (i == b_end) /* no errors */
+ comp->status = IDXD_COMP_STATUS_SUCCESS;
+ }
+ }
+
+ return ret;
+}
+
+uint16_t
+idxd_completed(void *dev_private, uint16_t qid __rte_unused, uint16_t max_ops,
+ uint16_t *last_idx, bool *has_error)
+{
+ struct idxd_dmadev *idxd = dev_private;
+ uint16_t batch, ret = 0;
+
+ do {
+ batch = batch_completed(idxd, max_ops - ret, has_error);
+ ret += batch;
+ } while (batch > 0 && *has_error == false);
+
+ *last_idx = idxd->ids_returned - 1;
+ return ret;
+}
+
+uint16_t
+idxd_completed_status(void *dev_private, uint16_t qid __rte_unused, uint16_t max_ops,
+ uint16_t *last_idx, enum rte_dma_status_code *status)
+{
+ struct idxd_dmadev *idxd = dev_private;
+ uint16_t batch, ret = 0;
+
+ do {
+ batch = batch_completed_status(idxd, max_ops - ret, &status[ret]);
+ ret += batch;
+ } while (batch > 0);
+
+ *last_idx = idxd->ids_returned - 1;
+ return ret;
+}
+
int
idxd_dump(const struct rte_dma_dev *dev, FILE *f)
{
@@ -93,5 +93,10 @@ int idxd_enqueue_copy(void *dev_private, uint16_t qid, rte_iova_t src,
int idxd_enqueue_fill(void *dev_private, uint16_t qid, uint64_t pattern,
rte_iova_t dst, unsigned int length, uint64_t flags);
int idxd_submit(void *dev_private, uint16_t qid);
+uint16_t idxd_completed(void *dev_private, uint16_t qid, uint16_t max_ops,
+ uint16_t *last_idx, bool *has_error);
+uint16_t idxd_completed_status(void *dev_private, uint16_t qid __rte_unused,
+ uint16_t max_ops, uint16_t *last_idx,
+ enum rte_dma_status_code *status);
#endif /* _IDXD_INTERNAL_H_ */