> -----Original Message----- > From: Trahe, Fiona [mailto:fiona.tr...@intel.com] > Sent: 11 December 2017 23:52 > To: Verma, Shally <shally.ve...@cavium.com>; dev@dpdk.org > Cc: Athreya, Narayana Prasad <narayanaprasad.athr...@cavium.com>; > Challa, Mahipal <mahipal.cha...@cavium.com>; De Lara Guarch, Pablo > <pablo.de.lara.gua...@intel.com>; Gupta, Ashish > <ashish.gu...@cavium.com>; Sahu, Sunila <sunila.s...@cavium.com>; > Trahe, Fiona <fiona.tr...@intel.com> > Subject: RE: [RFC v2] lib: add compressdev API > > > > > -----Original Message----- > > From: Verma, Shally [mailto:shally.ve...@cavium.com] > > Sent: Thursday, December 7, 2017 9:59 AM > > To: Trahe, Fiona <fiona.tr...@intel.com>; dev@dpdk.org > > Cc: Athreya, Narayana Prasad <narayanaprasad.athr...@cavium.com>; > Challa, Mahipal > > <mahipal.cha...@cavium.com>; De Lara Guarch, Pablo > <pablo.de.lara.gua...@intel.com>; Gupta, > > Ashish <ashish.gu...@cavium.com>; Sahu, Sunila > <sunila.s...@cavium.com> > > Subject: RE: [RFC v2] lib: add compressdev API > > > > > > > > > -----Original Message----- > > > From: Trahe, Fiona [mailto:fiona.tr...@intel.com] > > > Sent: 24 November 2017 22:26 > > > To: dev@dpdk.org; Verma, Shally <shally.ve...@cavium.com> > > > Cc: Challa, Mahipal <mahipal.cha...@cavium.com>; Athreya, Narayana > > > Prasad <narayanaprasad.athr...@cavium.com>; > > > pablo.de.lara.gua...@intel.com; fiona.tr...@intel.com > > > Subject: [RFC v2] lib: add compressdev API > > > > > > compressdev API > > > > > > Signed-off-by: Trahe, Fiona <fiona.tr...@intel.com> > > > --- > > > > //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? > > > [Fiona] I don't see a need for this and will just return what the PMD returns. > Yes, appl should call rte_compressdev_get_header_session_size() > And rte_compressdev_get_private_session_size() for (one device in) each > driver it wants the session to handle. > And pick the largest of these as the element size. > The idea is to use one mempool object for the hdr and another object for > each driver. > So if the session is intended to be used on 2 drivers, then the pool should be > sized so 3 objects are available (x max_nb_sessions). > Else the API layer would need to store offsets for each type of driver as > their > session size would be different. > Instead the API layer doesn't need offsets as each driver just grabs an object > from the pool and stores the ptr to this in the hdr array. > [Shally] Ok. Got it.
Thanks Shally > > > > + > > > +} > > //snip// > > > > Thanks > > Shally
