On 05.09.2005 [09:32:21 +0100], Russell King wrote: > On Mon, Sep 05, 2005 at 01:49:35PM +0530, Srivatsa Vaddagiri wrote: > > This is precisely what I have done. I have made cur_timer->mark-offset() to > > return the lost ticks and update wall-time from the callee, which > > can be either timer_interrupt handler or in dyn-tick case the dyn-tick > > code (I have called it dyn_tick_interrupt) which is called before > > processing > > _any_ interrupt. > > When you have a timer which constantly increments from 0 to MAX and > wraps, and you can set the value to match to cause an interrupt, > it makes more sense to handle it the way we're doing it (which > incidentally leads to no loss of precision.)
This is the way ppc works, I believe (match register). > Calculating the number of ticks missed, updating the kernel time, > and updating the timer match will cause problems with these - if > the timer has already past the number of ticks you originally > calculated, you may not get another interrupt for a long time. Yes, this is the source of much bugginess, especially with bad hardware :) > > If ARM had a timer_opts equivalent we could have followed > > I think your timer_opts is effectively our struct sys_timer. I agree, in looking over the two. Perhaps those structures could be served to be unified as well? John Stultz would be the one to talk to, though. Thanks, Nish - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
