Messages in this thread | | | Date | Wed, 16 Jan 2008 22:39:09 -0500 (EST) | From | Steven Rostedt <> | Subject | Re: [RFC PATCH 16/22 -v2] add get_monotonic_cycles |
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On Thu, 17 Jan 2008, Paul Mackerras wrote: > > It's very hard to do a per-thread counter in the VDSO, since threads > in the same process see the same memory, by definition. You'd have to > have an array of counters and have some way for each thread to know > which entry to read. Also you'd have to find space for tens or > hundreds of thousands of counters, since there can be that many > threads in a process sometimes.
I was thinking about this. What would also work is just the ability to read the schedule counter for the current cpu. Now this would require that the task had a way to know which CPU it was currently on.
-- Steve
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