On Mon, Nov 7, 2016 at 10:22 PM, Luis R. Rodriguez <mcg...@kernel.org> wrote: > On Thu, Oct 27, 2016 at 05:25:51PM +0200, Greg Kroah-Hartman wrote: >> On Wed, Oct 26, 2016 at 01:19:02PM +0200, Lukas Wunner wrote: >> > Hi Rafael, >> > >> > sorry for not responding to v5 of your series earlier, just sending >> > this out now in the hope that it reaches you before your travels. >> > >> > On Mon, Oct 10, 2016 at 02:51:04PM +0200, Rafael J. Wysocki wrote: >> > > - Modify device_links_check_suppliers(), device_links_driver_bound(), >> > > device_links_no_driver(), device_links_driver_cleanup(), >> > > device_links_busy(), >> > > and device_links_unbind_consumers() to walk link lists under >> > > device_links_lock >> > > (to make the new "driver presence tracking" mechanism work reliably). >> > >> > This change might increase boot time if drivers return -EPROBE_DEFER. >> >> "might"? Please verify this before guessing.... >> >> And don't make this more complex than needed before actually determining >> a real issue. > > As clarified by Rafael at Plumbers, this functional dependencies > framework assumes your driver / subsystem supports deferred probe,
It isn't particularly clear what you mean by "support" here. I guess that you mean that it will allow the ->probe callback to be invoked for multiple times for the same device/driver combination without issues. If that's the case, the way the new code uses -EPROBE_DEFER doesn't interfere with this, because it will not invoke the ->probe callbacks for consumers at all until their (required) suppliers are ready. > if it does not support its not clear what will happen.... I don't see any problems here, but if you see any, please just say what they are. > We have no explicit semantics to check if a driver / subsystem > supports deferred probe. That's correct, but then do we need it? Thanks, Rafael