Unverified Commit 096b52fd authored by Sergey Matyukevich's avatar Sergey Matyukevich Committed by Palmer Dabbelt
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perf: RISC-V: throttle perf events 



Call perf_sample_event_took() to report time spent in overflow
interrupts. Perf core uses these measurements to throttle
perf events properly.

Signed-off-by: default avatarSergey Matyukevich <sergey.matyukevich@syntacore.com>
Reviewed-by: default avatarAtish Patra <atishp@rivosinc.com>
Link: https://lore.kernel.org/r/20220830155306.301714-4-geomatsi@gmail.com


Signed-off-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
parent 1537bf26

drivers/perf/riscv_pmu_sbi.c

+4 −0
Original line number Diff line number Diff line
@@ -18,6 +18,7 @@ 
#include <linux/of_irq.h>

#include <linux/of.h>

#include <linux/cpu_pm.h>

#include <linux/sched/clock.h>



#include <asm/sbi.h>

#include <asm/hwcap.h>
@@ -570,6 +571,7 @@ static irqreturn_t pmu_sbi_ovf_handler(int irq, void *dev) 
	unsigned long overflow;

	unsigned long overflowed_ctrs = 0;

	struct cpu_hw_events *cpu_hw_evt = dev;

	u64 start_clock = sched_clock();



	if (WARN_ON_ONCE(!cpu_hw_evt))

		return IRQ_NONE;
@@ -638,7 +640,9 @@ static irqreturn_t pmu_sbi_ovf_handler(int irq, void *dev) 
			perf_event_overflow(event, &data, regs);

		}

	}



	pmu_sbi_start_overflow_mask(pmu, overflowed_ctrs);

	perf_sample_event_took(sched_clock() - start_clock);



	return IRQ_HANDLED;

}