Messages in this thread | | | Subject | Re: [PATCH 3/5] perf_counter: rework ioctl()s | From | Peter Zijlstra <> | Date | Mon, 11 May 2009 17:12:21 +0200 |
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On Mon, 2009-05-11 at 11:29 +1000, Paul Mackerras wrote: > Peter Zijlstra writes: > > > Corey noticed that ioctl()s on grouped counters didn't work on the whole group. > > This extends the ioctl() interface to take a second argument that is > > interpreted as a flags field. We then provide PERF_IOC_FLAG_GROUP to toggle > > the behaviour. > > > > Having this flag gives the greatest flexibility, allowing you to individually > > enable/disable/reset counters in a group, or all together. > > As far as enable/disable are concerned, I don't think this is really > necessary. My intention was that if you want to enable/disable a > whole group you just enable/disable the leader and leave all its > siblings enabled, since if the leader is disabled the whole group > can't go on. > > Corey's problem was that we have a bug where enabling the leader only > puts the leader on and not the enabled group members. I meant to send > a patch to fix that ages ago but I got distracted. I'll send out the > patch shortly.
Thanks, I missed that little detail.
Do we still want the new ioctl iteration flag?
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