Stefan Hajnoczi writes: > On Sun, Apr 28, 2013 at 09:25:15PM +0200, Lluís Vilanova wrote: >> Stefan Hajnoczi writes: >> >> > On Fri, Apr 26, 2013 at 02:15:46PM +0200, Lluís Vilanova wrote: >> > Advanced users will have to modify the QEMU source. >> >> >> > Basically I think putting a stable API in place here isn't going to fly. >> >> > In terms of the tracing subsystem I don't mind, but I think it's a >> >> > question for the larger QEMU community. >> >> >> >> What are you referring to as an API? The tracing events and their >> >> signatures? >> >> > The interface that dynamic instrumentation libraries use to interact >> > with QEMU. That means "stable" tracing events plus any operations that >> > libraries can perform (stop/stop vcpu, peek/poke memory, dirty bitmaps, >> > MMU, interrupts, etc). >> >> Not all events require being "stable", just a few that I established as >> "abstract" and relate to some very generic guest state (which in their most >> basic form can be boiled down to 5). As for the rest of the API and more >> controversial events, as I said I have no problem in maintaining a separate >> branch.
> Can you split the work into two patch series: > 1. Target-independent TCG events (e.g. vbbl_begin) > 2. "custom" trace backend that links custom C trace event handler > functions - but without dynamic libraries or stable API. > It loses the dynamic library and stable API features but would be easy > to merge. Yes, I was thinking about sending a mail along those lines too. This basically entails two series (2nd and 4th in my current branch): * Support for tracing events at TCG code generation time (basically auto-generating per-event TCG helpers - trace_<event>_tcg -, which call the actual tracing event - trace_<event> -). * The events themselves (calls to trace_<event>_tcg). I can then maintain instrumentation support and its public API on a separate branch. Still, I'm not sure when I'll have time for this, as it will require moving a few patches among the series I have now (and readjusting their contents). Thanks, Lluis -- "And it's much the same thing with knowledge, for whenever you learn something new, the whole world becomes that much richer." -- The Princess of Pure Reason, as told by Norton Juster in The Phantom Tollbooth