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Deadline scheduling: coming soon?
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ACPI for ARM?
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Posted Sep 25, 2013 13:39 UTC (Wed) by deater (subscriber, #11746)
I'm currently doing the RDPMC accesses directly. The eventual goal is to have the PAPI performance library use the interface; there are overhead issues with the interface I was dealing with first (sometimes it is slower to use RDPMC than to just use the read() syscall, for reasons that took me a long time to figure out. Thankfully there are workarounds).
In any case yes, the documentation is awful. I wrote the perf_event_open() manpage in an attempt to address this. I've been working on updating the RDPMC part of that recently, although had to spend time trying to sanely document this ABI issue instead.
Don't go by the example RDPMC code in perf_event.h, it's out of date and possibly never really worked. I've been meaning to send a patch to fix that.
Posted Sep 25, 2013 19:20 UTC (Wed) by mathstuf (subscriber, #69389)
Could a patch which replaces it with "TODO: Add an example" (or similar) be pushed for 3.12 at least? If there's anything worse than no documentation, it's bad documentation.
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