> > > > I didn't say anything magic, but a table of pointers that are very > > critical for the system running. Should we implement it with a single > > switch, like we discussed in San Diego to do with the system call table? > > > > That is, have a "normal" table, and a "trace" table. The trace table > > points to functions that have tracepoints. The first enabler of > > tracing switches the table to use the tracepoints, and the last > > disabler switches it back? > > > > That is certainly a reasonable implementation option. It is slightly less > usable than it is for system calls, though, because the vectors in > the IDTs are somewhat scrambled and so you can't just do an indirect jump to > the original vector content. This does get messy > because you also want to preserve registers... >
Peter, Steven, Thank you for explaining the reason why you think a time penalty should be zero and discussing its implementation. I will update my patch so that a time penalty makes zero and submit it shortly. Seiji -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
