On Thu, Jul 06, 2006 at 08:01:18AM -0700, Stephane Eranian wrote: > Hello, > > > In the context of the perfmon2 subsystem for processor with HyperThreading, > we need to know on which thread we are currently running. This comes from > the fact that the performance counters are shared between the two threads. > > We use the thread id (smt_id) because we split the counters in half > between the two threads such that two threads on the same core can run > with monitoring on. We are currently computing the smt_id from the > apicid as returned by a CPUID instruction. This is not very efficient. > > I looked through the i386 code and could not find a function nor > structure that would return this smt_id. In the cpuinfo_x86 structure > there is an apicid field that looks good, yet it does not seem to be > initialized nor used. > > Is cpuinfo_x86->apicid field obsolete? > If so, what is replacing it?
In i386, it is getting initialized in generic_identify() in common.c and it is getting used for example in intel_cacheinfo.c thanks, suresh _______________________________________________ perfmon mailing list [email protected] http://www.hpl.hp.com/hosted/linux/mail-archives/perfmon/
