Merge "perf: Add workaround for performance monitor irq burst" (ceb432de) · Commits · e / devices / android_kernel_oneplus_sm8150

arch/arm64/Kconfig

+11 −0

Original line number	Diff line number	Diff line
		@@ -1311,6 +1311,17 @@ config BUILD_ARM64_UNCOMPRESSED_KERNEL
		concatenated dtb.
		endchoice

		config KRYO_PMU_WORKAROUND
		bool "Workaround for PMU IRQ burst"
		default n
		depends on ARM_PMU
		help
		Disable Performance Monitor overflow interrupts
		when handling an monitor IRQ, to avoid simultaneous
		overflow interrupts from multiple monitors.

		Enable this flag for effect SoCs.

		config BUILD_ARM64_DT_OVERLAY
		bool "enable DT overlay compilation support"
		depends on OF

arch/arm64/kernel/perf_event.c

+55 −1

Original line number	Diff line number	Diff line
		@@ -677,6 +677,41 @@ static void armv8pmu_disable_event(struct perf_event *event)

		raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
		}
		#ifdef CONFIG_KRYO_PMU_WORKAROUND
		static inline u32 armv8pmu_get_enabled_ints(void)
		{
		u32 int_enset;

		int_enset = read_sysreg(pmintenset_el1);
		write_sysreg(0xffffffff, pmintenclr_el1);
		isb();
		return int_enset;
		}

		static inline u32 armv8pmu_update_enabled_ints(u32 value, int idx, int set)
		{
		if (set)
		value \|= BIT(ARMV8_IDX_TO_COUNTER(idx));
		else
		value &= ~(BIT(ARMV8_IDX_TO_COUNTER(idx)));

		return value;
		}

		static inline void armv8pmu_set_enabled_ints(u32 mask)
		{
		write_sysreg(mask, pmintenset_el1);
		isb();
		}
		#else
		static inline u32 armv8pmu_get_enabled_ints(void)
		{ return 0; }

		static inline u32 armv8pmu_update_enabled_ints(u32 value, int idx, int set)
		{ return value; }

		static inline void armv8pmu_set_enabled_ints(u32 mask) { }
		#endif

		static irqreturn_t armv8pmu_handle_irq(int irq_num, void *dev)
		{
		@@ -686,6 +721,12 @@ static irqreturn_t armv8pmu_handle_irq(int irq_num, void *dev)
		struct pmu_hw_events *cpuc = this_cpu_ptr(cpu_pmu->hw_events);
		struct pt_regs *regs;
		int idx;
		u32 enabled_ints;

		/*
		* Get enabled the PMU interrupts and mask all PMU interrupts.
		*/
		enabled_ints = armv8pmu_get_enabled_ints();

		/*
		* Get and reset the IRQ flags
		@@ -724,8 +765,16 @@ static irqreturn_t armv8pmu_handle_irq(int irq_num, void *dev)
		if (!armpmu_event_set_period(event))
		continue;

		if (perf_event_overflow(event, &data, regs))
		if (perf_event_overflow(event, &data, regs)) {
		cpu_pmu->disable(event);

		/*
		* Update the list of interrupts
		* that should be reenabled.
		*/
		enabled_ints = armv8pmu_update_enabled_ints(
		enabled_ints, idx, 0);
		}
		}

		/*
		@@ -737,6 +786,11 @@ static irqreturn_t armv8pmu_handle_irq(int irq_num, void *dev)
		*/
		irq_work_run();

		/*
		* Re-enable the PMU interrupts
		*/
		armv8pmu_set_enabled_ints(enabled_ints);

		return IRQ_HANDLED;
		}