> -----Original Message----- > From: dev [mailto:[email protected]] On Behalf Of Ananyev, Konstantin > Sent: Tuesday, January 23, 2018 3:12 PM > To: Thomas Monjalon <[email protected]> > Cc: Matan Azrad <[email protected]>; Gaëtan Rivet <[email protected]>; > Wu, Jingjing <[email protected]>; > [email protected]; Neil Horman <[email protected]>; Richardson, Bruce > <[email protected]> > Subject: Re: [dpdk-dev] [PATCH v3 7/7] app/testpmd: adjust ethdev port > ownership > > > > > -----Original Message----- > > From: Thomas Monjalon [mailto:[email protected]] > > Sent: Tuesday, January 23, 2018 2:19 PM > > To: Ananyev, Konstantin <[email protected]> > > Cc: Matan Azrad <[email protected]>; Gaëtan Rivet > > <[email protected]>; Wu, Jingjing <[email protected]>; > > [email protected]; Neil Horman <[email protected]>; Richardson, Bruce > > <[email protected]> > > Subject: Re: [PATCH v3 7/7] app/testpmd: adjust ethdev port ownership > > > > 23/01/2018 14:34, Ananyev, Konstantin: > > > If that' s the use case, then I think you need to set device ownership at > > > creation time - > > > inside dev_allocate(). > > > Again that would avoid such racing conditions inside testpmd. > > > > The devices must be allocated at a low level layer. > > No one arguing about that. > But we can provide owner id information to the low level. > > > When a new device appears (hotplug), an ethdev port should be allocated > > automatically if it passes the whitelist/blacklist policy test. > > Then we must decide who will manage this device. > > I suggest notifying the DPDK libs first. > > So a DPDK lib or PMD like failsafe can have the priority to take the > > ownership in its notification callback. > > Possible, but seems a bit overcomplicated. > Why not just: > > Have a global variable process_default_owner_id, that would be init once at > startup. > Have an LTS variable default_owner_id. > It will be used by rte_eth_dev_allocate() caller can set dev->owner_id at > creation time, > so port allocation and setting ownership - will be an atomic operation. > At the exit rte_eth_dev_allocate() will always reset default_owner_id=0: > > rte_eth_dev_allocate(...) > { > lock(owner_lock); > <allocate_port> > owner = RTE_PER_LCORE(default_owner_id); > if (owner == 0) > owner = process_default_owner_id; > set_owner(port, ..., owner); > unlock(owner_lock); > RTE_PER_LCORE(default_owner_id) = 0;
Or probably better to leave default_owner_id reset to the caller. Another thing - we can use same LTS variable in all control ops to allow/disallow changing of port configuration based on ownership. Konstantin > } > > So callers who don't need any special ownership - don't need to do anything. > Special callers (like failsafe) can set default_owenr_id just before calling > hotplug > handling routine. > > Konstantin > > >
