![]() | ||||||||||
Messages in this thread |
On Thu, 20 Oct 2005, john stultz wrote: > > > > > > John, would this cause any problems to keep cycle_t at s64? > > > > I mean at u64. > > Performance would be the only concern. It had been a u64 before I > started optimizing the code a bit. > > The real problem however was the timeofday_perioidic_hook() was being > starved. Since not all clocksources are 64 bits wide (although most do > not overflow as fast as 32bits of the TSC) I'm not sure that will always > solve the issue. > > Ingo: Should the periodic_hook() call be converted to using the ktimer > or some other interface to ensure that it will be regularly run at some > frequency (currently 50ms, but that can be changed)? > Thomas showed me a trick with the ktimers API, that I use to schedule my custom scheduler. If you set periodic_hook to be called via ktimer with a prio of -1, it will force the timer to be run in the timer interrupt instead of a softirq task. Now the issue is the latency this would cause and to make sure that periodic_hook only grabs raw locks. Ingo? -- Steve - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ | |||||||||
| Last update: 2005-10-20 17:01 [from the cache] ©2003-2008 | ||||||||||