Alexey Brodkin 36481cf7fb ARCv2: perf: Support sampling events using overflow interrupts ... In times of ARC 700 performance counters didn't have support of interrupt an so for ARC we only had support of non-sampling events. Put simply only "perf stat" was functional. Now with ARC HS we have support of interrupts in performance counters which this change introduces support of. ARC performance counters act in the following way in regard of interrupts generation. [1] A counter counts starting from value set in PCT_COUNT register pair [2] Once counter reaches value set in PCT_INT_CNT interrupt is raised Basic setup look like this: [1] PCT_COUNT = 0; [2] PCT_INT_CNT = __limit_value__; [3] Enable interrupts for that counter and let it run [4] Let counter reach its limit [5] Handle interrupt when it happens Note that PCT HW block is build in CPU core and so ints interrupt line (which is basically OR of all counters IRQs) is wired directly to top-level IRQC. That means do de-assert PCT interrupt it's required to reset IRQs from all counters that have reached their limit values. Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>		2015-08-27 14:57:43 +05:30
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asm	ARCv2: perf: Support sampling events using overflow interrupts	2015-08-27 14:57:43 +05:30
uapi/asm	ARC: Make pt_regs regs unsigned	2015-08-05 11:48:21 +05:30