ARM: 6742/1: pmu: avoid setting IRQ affinity on UP systems (71efb063) · Commits · 戴 / test

Now that we can execute a CONFIG_SMP kernel on a uniprocessor system, extra care has to be taken in the PMU IRQ affinity setting code to ensure that we don't always fail to initialise. This patch changes the CPU PMU initialisation code so that when we only have a single IRQ, whose affinity can not be changed at the controller, we report success (0) rather than -EINVAL. Reported-by:

Avik Sil <avik.sil@linaro.org> Acked-by:

Jamie Iles <jamie@jamieiles.com> Signed-off-by:

Will Deacon <will.deacon@arm.com> Signed-off-by:

Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/kernel/pmu.c

+14 −8

Original line number	Diff line number	Diff line
		@@ -97,28 +97,34 @@ set_irq_affinity(int irq,
		irq, cpu);
		return err;
		#else
		return 0;
		return -EINVAL;
		#endif
		}

		static int
		init_cpu_pmu(void)
		{
		int i, err = 0;
		int i, irqs, err = 0;
		struct platform_device *pdev = pmu_devices[ARM_PMU_DEVICE_CPU];

		if (!pdev) {
		err = -ENODEV;
		goto out;
		}
		if (!pdev)
		return -ENODEV;

		irqs = pdev->num_resources;

		/*
		* If we have a single PMU interrupt that we can't shift, assume that
		* we're running on a uniprocessor machine and continue.
		*/
		if (irqs == 1 && !irq_can_set_affinity(platform_get_irq(pdev, 0)))
		return 0;

		for (i = 0; i < pdev->num_resources; ++i) {
		for (i = 0; i < irqs; ++i) {
		err = set_irq_affinity(platform_get_irq(pdev, i), i);
		if (err)
		break;
		}

		out:
		return err;
		}

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