On Tue, 2007-07-03 at 23:17 -0400, Mathieu Desnoyers wrote: > * Tom Zanussi ([EMAIL PROTECTED]) wrote: > > This patch adds the ability to explicitly specify the per-cpu buffer > > to reserve space in. Needed for early DTI tracing. > > > > This should come with the ability to tell relay where the already > allocated static buffers are. Can you tell me a little more on why the > standard relay_reserve would not do the job? Is smp_processor_id() not > ready to output a sensible CPU id yet ? >
In the case of early tracing, the DTI code uses a global buffer and saves the cpuid along with each event. Later, when the relay channel is available, the relogging code wants to put each event in the appropriate per-cpu relay buffer. The standard relay_reserve() always uses the current cpuid, rather than the cpuid attached to the event, which is not what we want. relay_reserve_cpu() simply allows a cpuid other than the current one to be used. Tom - 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/
