Commit bf22ff45 authored by Jeffy Chen's avatar Jeffy Chen Committed by Thomas Gleixner
Browse files

genirq: Avoid unnecessary low level irq function calls 



Check irq state in enable/disable/unmask/mask_irq to avoid unnecessary
low level irq function calls.

This has two advantages:
    - Conditionals are faster than hardware access

    - Solves issues with the underlying refcounting of the pinctrl
      infrastructure

Suggested-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarJeffy Chen <jeffy.chen@rock-chips.com>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Cc: tfiga@chromium.org
Cc: briannorris@chromium.org
Cc: dianders@chromium.org
Link: http://lkml.kernel.org/r/1498476814-12563-2-git-send-email-jeffy.chen@rock-chips.com
parent d829b8fb

kernel/irq/chip.c

+33 −20
Original line number Diff line number Diff line
@@ -314,16 +314,25 @@ void irq_shutdown(struct irq_desc *desc) 


void irq_enable(struct irq_desc *desc)

{

	if (!irqd_irq_disabled(&desc->irq_data)) {

		unmask_irq(desc);

	} else {

		irq_state_clr_disabled(desc);

	if (desc->irq_data.chip->irq_enable)

		if (desc->irq_data.chip->irq_enable) {

			desc->irq_data.chip->irq_enable(&desc->irq_data);

	else

		desc->irq_data.chip->irq_unmask(&desc->irq_data);

			irq_state_clr_masked(desc);

		} else {

			unmask_irq(desc);

		}

	}

}



static void __irq_disable(struct irq_desc *desc, bool mask)

{

	if (irqd_irq_disabled(&desc->irq_data)) {

		if (mask)

			mask_irq(desc);

	} else {

		irq_state_set_disabled(desc);

		if (desc->irq_data.chip->irq_disable) {

			desc->irq_data.chip->irq_disable(&desc->irq_data);
@@ -332,6 +341,7 @@ static void __irq_disable(struct irq_desc *desc, bool mask) 
			mask_irq(desc);

		}

	}

}



/**

 * irq_disable - Mark interrupt disabled
@@ -378,18 +388,21 @@ void irq_percpu_disable(struct irq_desc *desc, unsigned int cpu) 


static inline void mask_ack_irq(struct irq_desc *desc)

{

	if (desc->irq_data.chip->irq_mask_ack)

	if (desc->irq_data.chip->irq_mask_ack) {

		desc->irq_data.chip->irq_mask_ack(&desc->irq_data);

	else {

		desc->irq_data.chip->irq_mask(&desc->irq_data);

		irq_state_set_masked(desc);

	} else {

		mask_irq(desc);

		if (desc->irq_data.chip->irq_ack)

			desc->irq_data.chip->irq_ack(&desc->irq_data);

	}

	irq_state_set_masked(desc);

}



void mask_irq(struct irq_desc *desc)

{

	if (irqd_irq_masked(&desc->irq_data))

		return;



	if (desc->irq_data.chip->irq_mask) {

		desc->irq_data.chip->irq_mask(&desc->irq_data);

		irq_state_set_masked(desc);
@@ -398,6 +411,9 @@ void mask_irq(struct irq_desc *desc) 


void unmask_irq(struct irq_desc *desc)

{

	if (!irqd_irq_masked(&desc->irq_data))

		return;



	if (desc->irq_data.chip->irq_unmask) {

		desc->irq_data.chip->irq_unmask(&desc->irq_data);

		irq_state_clr_masked(desc);
@@ -411,10 +427,7 @@ void unmask_threaded_irq(struct irq_desc *desc) 
	if (chip->flags & IRQCHIP_EOI_THREADED)

		chip->irq_eoi(&desc->irq_data);



	if (chip->irq_unmask) {

		chip->irq_unmask(&desc->irq_data);

		irq_state_clr_masked(desc);

	}

	unmask_irq(desc);

}



/*

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