vvOn Fri 2011-06-10 14:30:30, Peter Zijlstra wrote: >On Fri, 2011-06-10 at 13:28 +0200, Peter Zijlstra wrote: > > On Thu, 2011-06-09 at 16:57 -0700, Hugh Dickins wrote: > > > > > > All console-related activity curently happens under spin_lock_irqsave(&console_lock). > > > This causes interrutps to be blocked for 1-2 milliseconds with vgacon, and for > > > hundreds of milliseconds with fbdevs. This results in network overruns, audio > > > dropouts, dropped characters on serial ports and other such nice things. > > > > Hmm, with these proposed patches we're actually back to that. I wonder > > if fbdev is still that crappy.. > > So I tried adding a fbcon to my test box (not that it actually has a > display, but who cares) and disabled lockdep (otherwise that's all I can > catch on the latency tracer) to see if I could see whopping horrid > latencies there, but I'm afraid I either failed to set things up > properly or my fbcon isn't sucky enough. > > What I did was enable: > > CONFIG_FB=y > CONFIG_FB_SIS=y > CONFIG_FB_SIS_315=y (the board has XGI z7) sis will be accelerated. Try vesafb; scrolling should be horrible. -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
