linux-imx

// SPDX-License-Identifier: GPL-2.0

/*

 * Functions related to interrupt-poll handling in the block layer. This

 * is similar to NAPI for network devices.

 */

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/init.h>

#include <linux/bio.h>

#include <linux/interrupt.h>

#include <linux/cpu.h>

#include <linux/irq_poll.h>

#include <linux/delay.h>

​

static unsigned int irq_poll_budget __read_mostly = 256;

​

static DEFINE_PER_CPU(struct list_head, blk_cpu_iopoll);

​

/**

 * irq_poll_sched - Schedule a run of the iopoll handler

 * @iop:      The parent iopoll structure

 *

 * Description:

 *     Add this irq_poll structure to the pending poll list and trigger the

 *     raise of the blk iopoll softirq.

 **/

void irq_poll_sched(struct irq_poll *iop)

{

    unsigned long flags;

​

    if (test_bit(IRQ_POLL_F_DISABLE, &iop->state))

        return;

    if (test_and_set_bit(IRQ_POLL_F_SCHED, &iop->state))

        return;

​

    local_irq_save(flags);

    list_add_tail(&iop->list, this_cpu_ptr(&blk_cpu_iopoll));

    raise_softirq_irqoff(IRQ_POLL_SOFTIRQ);

    local_irq_restore(flags);

}

EXPORT_SYMBOL(irq_poll_sched);

​

/**

 * __irq_poll_complete - Mark this @iop as un-polled again

 * @iop:      The parent iopoll structure

 *

 * Description:

 *     See irq_poll_complete(). This function must be called with interrupts

 *     disabled.

 **/

static void __irq_poll_complete(struct irq_poll *iop)

{

    list_del(&iop->list);

    smp_mb__before_atomic();

    clear_bit_unlock(IRQ_POLL_F_SCHED, &iop->state);

}

​

/**

 * irq_poll_complete - Mark this @iop as un-polled again

 * @iop:      The parent iopoll structure

 *

 * Description:

 *     If a driver consumes less than the assigned budget in its run of the