(2014/07/21 21:24), Hemant Kumar wrote: > > On 07/20/2014 08:46 AM, Masami Hiramatsu wrote: >> (2014/07/20 2:32), Hemant Kumar wrote: >>>>> [SNIP] >>>>> First, scan the binaries using : >>>>> # perf list sdt --scan >>>> At a glance, maybe we'd better have perf sdt-cache as like as perf >>>> buildid-cache >>>> for manage sdt information. what would you think? >>>> >>> I agree with you having perf sdt-cache similar to perf buildid-cache. >>> But I think if the functionality of perf sdt-cache is only to build the >>> cache, then we can >>> go with the perf list sdt --scan. Since, "perf list sdt" is used for >>> other purposes too, it >>> should be less confusing for the users to just add another option >>> (--scan) to create/modify >>> the cache. What do you suggest? >> I think there may be some other cases, for example adding user local build >> binary to the cache, or remove/update it locally. :) >> >> And also, in user's mental model of perf-list, it doesn't take an "active" >> action, that always does "passive" action. So adding such "active" scan >> option >> will be more confusing. > > Ok, I understand now. > >> But I also think it is OK that if the sdt is never scanned, the perf-list >> automatically scans in background (without any option) or suggests user >> to run "perf sdt-cache --scan". (it depends on how long time it may take) >> >> To summarize it, I'd like to suggest adding below functions; >> >> perf list sdt : shows all cached SDT events >> perf list sdt <file> : shows SDT events in <file> >> perf sdt-cache --scan/-s : scans all system binaries/libraries + added files >> perf sdt-cache --add/-a <file(s)> : add SDT events in <file> to cache >> perf sdt-cache --remove/-r <file(s)>: remove SDT events in <file> from cache > > Yeah, I agree with the above mentioned functions. > > So, according to this, if perf list sdt <file> can't find the SDT events > for that file > in the SDT cache, should it say "use perf sdt-cache --add <file> to add > the SDT > events for that file to the cache", or silently, should add that file's > SDT events > to SDT cache?
Hmm, it's a good question. Since the SDT events will be used as a normal events, perf-record may NOT take an option of execfile in where SDT events are. This means that if the given events are not cached, perf-record always fails. Thus, I think we have 2 options, one is just removing "perf-list sdt <file>" support, or another is "perf-list sdt <file>" silently caches the SDT in <file>. IMHO, at the first version, we'd better just removes "perf-list sdt <file>" support, since it is very simple model. And if someone asks supporting that, we can add that afterwords as an enhancement. ;) Thank you, -- Masami HIRAMATSU Software Platform Research Dept. Linux Technology Research Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: masami.hiramatsu...@hitachi.com -- 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/
