Jan Kiszka wrote: > Avi Kivity wrote: > >> Liu, Eric E wrote: >> >>> Hi, >>> The following patches port xentrace to kvm which is useful for >>> performance tuning and debugging. >>> >>> It is designed to allow debugging traces of kvm to be generated on >>> Up/Smp machines. Each trace entry is outputted in a trace ring buffer >>> for per cpu which is mapped to userspace, and the userspace tools can >>> analyze the data according to some formats definitions. >>> >>> Since we already have had debugfs_entries and some other kernel debug >>> mechanism to use, does this kvmtrace make sense? Any comment is >>> welcomed. >>> >>> >> This looks very useful. While kvm_stat provides good data, this is much >> more in depth. >> >> The kernel already contains a method of transferring percpu data to >> userspace; see Documentation/filesystems/relay.txt. It supports mmap() >> and read(). Please see if it is a good fit. >> > > I would also suggest to use the new kernel standard for instrumentation: > trace_mark(). > > This would also allow to reuse the trace points with other tracer and > maybe even obsolete a separate transportation channel, e.g. when LTTng > is once :-/ merged. >
Can one have markers automatically recorded? Or do you need to connect the marker with a logging function? If the latter, it's too difficult to use. -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
