On 02/02/2012 07:55 PM, Xiao Guangrong wrote: > On 02/03/2012 01:36 AM, Avi Kivity wrote: > > > On 02/02/2012 07:27 PM, Xiao Guangrong wrote: > >> From: Xiao Guangrong <[email protected]> > >> > >> 'perf kvm-events' will use kvm_exit and kvm_mmio(read...) to calculate > >> mmio read emulated time for the old kernel, in order to trace mmio read > >> event more exactly, we add kvm_mmio_begin to trace the time when mmio read > >> begins > >> > >> Also, add kvm_mmio_done to trace the time when mmio/pio is completed > > > > Previously, we discussed using the kvm_entry to do this. This reduces > > the number of tracepoints, and is backwards compatible. What was the > > conclusion? > > > > > Since using kvm_entry can cause lots of unnecessary calculated, these new two > tracepoints can let the result be exacter.
Do you have numbers on the ratio between kvm_entry traces and kvm_mmio_begin/end traces? > And, they are only used in new kernel, we will fall back to using kvm_entry if > they are not existing, that means it does not break backwards compatible. Ah ok. -- error compiling committee.c: too many arguments to function -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
