On Mon, Oct 15, 2012 at 2:49 PM, Jesse Barnes <jbarnes at virtuousgeek.org> wrote: > On Mon, 15 Oct 2012 12:32:05 +1000 > Dave Airlie <airlied at gmail.com> wrote: > >> > The console lock can be contended, so rather than prevent other drivers >> > after us from being held up, queue the console suspend into the global >> > work queue that can happen anytime. I've measured this to take around >> > 200ms on my T420. Combined with the ring freq/turbo change, we should >> > save almost 1/2 a second on resume. >> >> Did you measure booting with quiet? I can't think what else could be >> contending on this lock other than printk, now maybe we should reduce >> the printk noise! >> >> This will make debugging things even worse than they are, since you >> don't see any printks on the screen until after we do this. > > I thought I measured with quiet, but I'll double check. > > Not sure about debugging; it's pretty bad to begin with. I generally > use netconsole or the "stare really hard at the code" method when it > comes to suspend/resume or init time anyway. > > But yeah, some investigation into the console lock contention is > probably a good idea at any rate. A typical distro config probably > also has some other fbcon driver and probably vgacon built-in too, and > I haven't checked what they do. > If they are still there at s/r time you now have two problems. Dave.
