G'Day Masami-san, Namhyung, I'm really looking forward to this feature -- very useful, thanks!...
On Sat, Jul 18, 2015 at 9:24 PM, Namhyung Kim <namhy...@kernel.org> wrote: > Hi Masami, > > On Fri, Jul 17, 2015 at 12:21:42PM +0900, Masami Hiramatsu wrote: >> Now I'm thinking that we should avoid using %event syntax for perf-list >> and perf-record to avoid confusion. For example, suppose that we have >> "libfoo:bar" SDT event, when we just scanned the libfoo binary and >> use it via perf-record, we'll run perf record -e "%libfoo:bar". >> However, after we set the probe via perf-probe, we have to run >> perf record -e "libfoo:bar". That difference looks no good. >> So, I think in both case it should accept -e "libfoo:bar" syntax. > > I don't remember how the SDT events should be shown to users. Sorry > if I'm missing something here. > > AFAIK an SDT event consists of a provider and an event name. So it > can be simply 'provider:event' like tracepoints or > 'binary:provider_event' like uprobes. > > I like the former because it's simpler but it needs to guarantee that > it doesn't clash with existing tracepoints/[ku]probes. So IIUC we > chose the '%' sign to distinguish them. But after setting a probe at > it, the group name should be the binary name. So the whole event name > might be changed, and this is not good. I don't think we should worry about the clash, as the provider name should differentiate. So I think "libfoo:bar" with perf record is better. After adding them to the cache (via % if needed), I'd think they would be best looking like tracepoints. Eg, listing them together they can be differentiated, something like: # perf list [...] block:block_rq_abort [Tracepoint event] block:block_rq_requeue [Tracepoint event] block:block_rq_complete [Tracepoint event] [...] libc:memory_heap_new [User tracepoint event] libc:memory_heap_free [User tracepoint event] libc:memory_heap_more [User tracepoint event] [...] Then used the same. Brendan -- 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/
