On Friday 22 May 2009 9:44:18 am Scott Long wrote: > John Baldwin wrote: > > On Thursday 21 May 2009 6:11:02 pm Attilio Rao wrote: > >> At this point I wonder what's the purpose of maintaining the sleeping > >> version for such functions? > > > > Actually, I still very much do not like using M_NOWAIT needlessly. I would > > much rather the solution for make_dev() be that the 1 or 2 places that need > > to do it with a mutex held instead queue a task to do the actual make_dev() > > in a taskqueue when no locks are held. This is basically what > > destroy_dev_sched() is doing. Perhaps a make_dev_sched() with a similar > > callback to be called on completion would be better. Having a device > > driver > > do all the work to setup the hardware only to fail to create a node in /dev > > so that userland can actually use it is pretty rediculous and useless. > > > > It's a lot easier for me to handle a failure of make_dev in CAM than it > is to decouple the call to it. Please don't dictate policy.
But what is there for CAM to handle? I would expect CAM to handle hardware events such as the devices arriving or leaving. A temporary memory shortage it not a hardware event. As a user, if I insert a USB stick when the system happens to be temporarily low on memory, is it more useful for the cdev to appear a few microseconds later from a deferred context once memory is available or for no device to ever appear at all? -- John Baldwin _______________________________________________ svn-src-all@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
