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Vineet Gupta authored
As part of fixing another perf issue, observed that after a perf run, the interrupt got disabled on one/more cores. Turns out that despite requesting perf irq as percpu, the flow handler registered was not handle_percpu_irq() Given that on ARCv2 cores, IRQs < 24 are always private to cpu, we register the right handler at the very onset. Before Fix | [ARCLinux]# cat /proc/interrupts | grep perf | 20: 0 0 0 0 ARCv2 core Intc 20 ARC perf counters | | [ARCLinux]# perf record -c 20000 /sbin/hackbench | Running with 10*40 (== 400) tasks. | | [ARCLinux]# cat /proc/interrupts | grep perf | 20: 0 522 8 51916 ARCv2 core Intc 20 ARC perf counters | | [ARCLinux]# perf record -c 20000 /sbin/hackbench | Running with 10*40 (== 400) tasks. | | [ARCLinux]# cat /proc/interrupts | grep perf | 20: 0 522 8 104368 ARCv2 core Intc 20 ARC perf counters After Fix | [ARCLinux]# cat /proc/interrupts | grep perf | 20: 0 0 0 0 ARCv2 core Intc 20 ARC perf counters | | [ARCLinux]# perf record -c 20000 /sbin/hackbench | Running with 10*40 (== 400) tasks. | | [ARCLinux]# cat /proc/interrupts | grep perf | 20: 64198 62012 62697 67803 ARCv2 core Intc 20 ARC perf counters | | [ARCLinux]# perf record -c 20000 /sbin/hackbench | Running with 10*40 (== 400) tasks. | | [ARCLinux]# cat /proc/interrupts | grep perf | 20: 126014 122792 123301 133654 ARCv2 core Intc 20 ARC perf counters Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Alexey Brodkin <abrodkin@synopsys.com> Cc: stable@vger.kernel.org #4.2+ Cc: linux-kernel@vger.kernel.org Signed-off-by:
Vineet Gupta <vgupta@synopsys.com>
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