On Thu, 2012-08-23 at 12:00 +0900, Masami Hiramatsu wrote: > (2012/08/23 11:01), Masami Hiramatsu wrote: > > (2012/08/22 22:41), Steven Rostedt wrote: > >> On Wed, 2012-08-22 at 17:43 +0900, Yoshihiro YUNOMAE wrote: > >>> From: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx> > >>> > >>> Count debugfs/tracing/per_cpu/cpu* to determine the > >>> number of CPUs. > >> > >> I'm curious, do you find that sysconf doesn't return the # of CPUs the > >> system has? > > > > No, sysconf returns the number of hosts CPUs, not guests. > > > >> I've had boxes where the per_cpu/cpu* had more cpus than the > >> box actually holds. But this was a bug in the kernel, not the tool. This > >> change log needs to have rational instead of just explaining what the > >> patch does. > > > > Ah, I see. Hmm, then this should be enabled by a command line > > option or an environment variable. > > Oops, I misunderstood. I'll add more comment for why this > should be tried instead of sysconf. And now that I understand why you are doing this, why not only do this if the TRACE_AGENT or DEBUG_TRACING_DIR is defined. That is, if we are doing it against a bare metal system, then sysconf should suffice, but if we are tracing against a guest, then it should use the tracing directory to determine the buffers. We could add options to override this, but I would think the default should just Do The Right Thing(tm). -- Steve _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
