Messages in this thread | | | Subject | Re: [PATCH 4/6] perf_counter: Add PERF_COUNTER_IOC_SET_FILTER ioctl | From | Tom Zanussi <> | Date | Wed, 09 Sep 2009 23:45:57 -0500 |
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On Wed, 2009-09-09 at 10:18 +0800, Li Zefan wrote: > >>>> Hrm,.. not at all sure about this.. what are the ABI implications? > >>> I think the ABI should be fine if it's always a sub-set of C syntax. > >>> That would be C expressions initially. Hm? > >> Right, so I've no clue what filter expressions look like, and the > >> changelog doesn't help us at all. It doesn't mention its a well > >> considered decision to henceforth freeze the expression syntax. > >> > >> Of course, since filters so far only work with tracepoint things, and > >> since you can only come by tracepoint things through debugfs, and since > >> anything debugfs is basically a free-for-all ABI-less world, we might be > >> good, but then this is a very ill-defined ioctl() indeed. > >> > >> So please, consider this well -- there might not be a second chance. > >> > > > > I've been meaning to write up something about the event filters - here's > > a first stab that hopefully helps explain them... > > > > Great! > > Reviewed-by: Li Zefan <lizf@cn.fujitsu.com> > > Could you add your SOB and send it to Ingo? > > Some nitpicks below:
Sure, I'll send a new version shortly - thanks for the suggestions.
Tom
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