[dpdk-dev] [PATCH v3 05/25] raw/ioat: add a flag to control copying handle parameters

[Bruce Richardson <bruce.richardson@intel.com>]

From: Cheng Jiang <Cheng1.jiang@intel.com>

Add a flag which controls whether rte_ioat_enqueue_copy and
rte_ioat_completed_copies function should process handle parameters. Not
doing so can improve the performance when handle parameters are not
necessary.

Signed-off-by: Cheng Jiang <Cheng1.jiang@intel.com>
Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
Reviewed-by: Kevin Laatz <kevin.laatz@intel.com>
---
 doc/guides/rawdevs/ioat.rst            |  3 ++
 doc/guides/rel_notes/release_20_11.rst |  6 ++++
 drivers/raw/ioat/ioat_rawdev.c         |  2 ++
 drivers/raw/ioat/rte_ioat_rawdev.h     | 45 +++++++++++++++++++-------
 4 files changed, 45 insertions(+), 11 deletions(-)

diff --git a/doc/guides/rawdevs/ioat.rst b/doc/guides/rawdevs/ioat.rst
index c46460ff4..af00d77fb 100644
--- a/doc/guides/rawdevs/ioat.rst
+++ b/doc/guides/rawdevs/ioat.rst
@@ -129,6 +129,9 @@ output, the ``dev_private`` structure element cannot be NULL, and must
 point to a valid ``rte_ioat_rawdev_config`` structure, containing the ring
 size to be used by the device. The ring size must be a power of two,
 between 64 and 4096.
+If it is not needed, the tracking by the driver of user-provided completion
+handles may be disabled by setting the ``hdls_disable`` flag in
+the configuration structure also.
 
 The following code shows how the device is configured in
 ``test_ioat_rawdev.c``:
diff --git a/doc/guides/rel_notes/release_20_11.rst b/doc/guides/rel_notes/release_20_11.rst
index 4eb3224a7..196209f63 100644
--- a/doc/guides/rel_notes/release_20_11.rst
+++ b/doc/guides/rel_notes/release_20_11.rst
@@ -78,6 +78,12 @@ New Features
     ``--portmask=N``
     where N represents the hexadecimal bitmask of ports used.
 
+* **Updated ioat rawdev driver**
+
+  The ioat rawdev driver has been updated and enhanced. Changes include:
+
+  * Added a per-device configuration flag to disable management of user-provided completion handles
+
 
 Removed Items
 -------------
diff --git a/drivers/raw/ioat/ioat_rawdev.c b/drivers/raw/ioat/ioat_rawdev.c
index 0732b059f..ea9f51ffc 100644
--- a/drivers/raw/ioat/ioat_rawdev.c
+++ b/drivers/raw/ioat/ioat_rawdev.c
@@ -58,6 +58,7 @@ ioat_dev_configure(const struct rte_rawdev *dev, rte_rawdev_obj_t config,
 		return -EINVAL;
 
 	ioat->ring_size = params->ring_size;
+	ioat->hdls_disable = params->hdls_disable;
 	if (ioat->desc_ring != NULL) {
 		rte_memzone_free(ioat->desc_mz);
 		ioat->desc_ring = NULL;
@@ -122,6 +123,7 @@ ioat_dev_info_get(struct rte_rawdev *dev, rte_rawdev_obj_t dev_info,
 		return -EINVAL;
 
 	cfg->ring_size = ioat->ring_size;
+	cfg->hdls_disable = ioat->hdls_disable;
 	return 0;
 }
 
diff --git a/drivers/raw/ioat/rte_ioat_rawdev.h b/drivers/raw/ioat/rte_ioat_rawdev.h
index 3d8419271..28ce95cc9 100644
--- a/drivers/raw/ioat/rte_ioat_rawdev.h
+++ b/drivers/raw/ioat/rte_ioat_rawdev.h
@@ -38,7 +38,8 @@ extern "C" {
  * an ioat rawdev instance.
  */
 struct rte_ioat_rawdev_config {
-	unsigned short ring_size;
+	unsigned short ring_size; /**< size of job submission descriptor ring */
+	bool hdls_disable;    /**< if set, ignore user-supplied handle params */
 };
 
 /**
@@ -56,6 +57,7 @@ struct rte_ioat_rawdev {
 
 	unsigned short ring_size;
 	struct rte_ioat_generic_hw_desc *desc_ring;
+	bool hdls_disable;
 	__m128i *hdls; /* completion handles for returning to user */
 
 
@@ -88,10 +90,14 @@ struct rte_ioat_rawdev {
  *   The length of the data to be copied
  * @param src_hdl
  *   An opaque handle for the source data, to be returned when this operation
- *   has been completed and the user polls for the completion details
+ *   has been completed and the user polls for the completion details.
+ *   NOTE: If hdls_disable configuration option for the device is set, this
+ *   parameter is ignored.
  * @param dst_hdl
  *   An opaque handle for the destination data, to be returned when this
- *   operation has been completed and the user polls for the completion details
+ *   operation has been completed and the user polls for the completion details.
+ *   NOTE: If hdls_disable configuration option for the device is set, this
+ *   parameter is ignored.
  * @param fence
  *   A flag parameter indicating that hardware should not begin to perform any
  *   subsequently enqueued copy operations until after this operation has
@@ -126,8 +132,10 @@ rte_ioat_enqueue_copy(int dev_id, phys_addr_t src, phys_addr_t dst,
 	desc->u.control_raw = (uint32_t)((!!fence << 4) | (!(write & 0xF)) << 3);
 	desc->src_addr = src;
 	desc->dest_addr = dst;
+	if (!ioat->hdls_disable)
+		ioat->hdls[write] = _mm_set_epi64x((int64_t)dst_hdl,
+					(int64_t)src_hdl);
 
-	ioat->hdls[write] = _mm_set_epi64x((int64_t)dst_hdl, (int64_t)src_hdl);
 	rte_prefetch0(&ioat->desc_ring[ioat->next_write & mask]);
 
 	ioat->enqueued++;
@@ -174,19 +182,29 @@ rte_ioat_get_last_completed(struct rte_ioat_rawdev *ioat, int *error)
 /**
  * Returns details of copy operations that have been completed
  *
- * Returns to the caller the user-provided "handles" for the copy operations
- * which have been completed by the hardware, and not already returned by
- * a previous call to this API.
+ * If the hdls_disable option was not set when the device was configured,
+ * the function will return to the caller the user-provided "handles" for
+ * the copy operations which have been completed by the hardware, and not
+ * already returned by a previous call to this API.
+ * If the hdls_disable option for the device was set on configure, the
+ * max_copies, src_hdls and dst_hdls parameters will be ignored, and the
+ * function returns the number of newly-completed operations.
  *
  * @param dev_id
  *   The rawdev device id of the ioat instance
  * @param max_copies
  *   The number of entries which can fit in the src_hdls and dst_hdls
- *   arrays, i.e. max number of completed operations to report
+ *   arrays, i.e. max number of completed operations to report.
+ *   NOTE: If hdls_disable configuration option for the device is set, this
+ *   parameter is ignored.
  * @param src_hdls
- *   Array to hold the source handle parameters of the completed copies
+ *   Array to hold the source handle parameters of the completed copies.
+ *   NOTE: If hdls_disable configuration option for the device is set, this
+ *   parameter is ignored.
  * @param dst_hdls
- *   Array to hold the destination handle parameters of the completed copies
+ *   Array to hold the destination handle parameters of the completed copies.
+ *   NOTE: If hdls_disable configuration option for the device is set, this
+ *   parameter is ignored.
  * @return
  *   -1 on error, with rte_errno set appropriately.
  *   Otherwise number of completed operations i.e. number of entries written
@@ -212,6 +230,11 @@ rte_ioat_completed_copies(int dev_id, uint8_t max_copies,
 		return -1;
 	}
 
+	if (ioat->hdls_disable) {
+		read += count;
+		goto end;
+	}
+
 	if (count > max_copies)
 		count = max_copies;
 
@@ -229,7 +252,7 @@ rte_ioat_completed_copies(int dev_id, uint8_t max_copies,
 		src_hdls[i] = hdls[0];
 		dst_hdls[i] = hdls[1];
 	}
-
+end:
 	ioat->next_read = read;
 	ioat->completed += count;
 	return count;
-- 
2.25.1