-----Original Message-----
From: Trahe, Fiona [mailto:fiona.trahe@intel.com]
Sent: 24 November 2017 22:26
To: dev@dpdk.org; Verma, Shally <redacted>
Cc: Challa, Mahipal <redacted>; Athreya, Narayana
Prasad [off-list ref];
pablo.de.lara.guarch@intel.com; fiona.trahe@intel.com
Subject: [RFC v2] lib: add compressdev API

compressdev API

Signed-off-by: Trahe, Fiona <redacted>
---

//snip//

+unsigned int
+rte_compressdev_get_header_session_size(void)
+{
+	/*
+	 * Header contains pointers to the private data
+	 * of all registered drivers
+	 */
+	return (sizeof(void *) * nb_drivers);
+}
+
+unsigned int
+rte_compressdev_get_private_session_size(uint8_t dev_id)
+{
+	struct rte_compressdev *dev;
+	unsigned int header_size = sizeof(void *) * nb_drivers;
+	unsigned int priv_sess_size;
+
+	if (!rte_compressdev_pmd_is_valid_dev(dev_id))
+		return 0;
+
+	dev = rte_compressdev_pmd_get_dev(dev_id);
+
+	if (*dev->dev_ops->session_get_size == NULL)
+		return 0;
+
+	priv_sess_size = (*dev->dev_ops->session_get_size)(dev);
+
+	/*
+	 * If size is less than session header size,
+	 * return the latter, as this guarantees that
+	 * sessionless operations will work
+	 */

[Shally] believe this comment need an edit

+	if (priv_sess_size < header_size)
+		return header_size;
+
+	return priv_sess_size;

[Shally] This doesn't return header_size inclusive which is fine as per API definition. So should application call 
rte_compressdev_get_header_session_size() in case it want to know header_size overhead per session and allocate pool with elt_size = sess_header_size + dev_priv_sz?

+
+}

//snip//

Thanks
Shally