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Revision d16cd297d288e48482c3c261db434a2e13bd9f20 authored by James Bottomley on 02 December 2010, 23:36:47 UTC, committed by Kyle McMartin on 04 December 2010, 16:14:32 UTC 
parisc: fix dino/gsc interrupts
 
The essential problem we're currently having is that dino (and gsc) is a
cascaded CPU interrupt.  Under the old __do_IRQ() handler, our CPU
interrupts basically did an ack followed by an end.  In the new scheme,
we replaced them with level handlers which do a mask, an ack and then an
unmask (but no end).  Instead, with the renaming of end to eoi, we
actually want to call the percpu flow handlers, because they actually
have all the characteristics we want.

This patch does the conversion and gets my C360 booting again.

Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
1 parent 67bace7
Raw File
noop-iosched.c 
/*
 * elevator noop
 */
#include <linux/blkdev.h>
#include <linux/elevator.h>
#include <linux/bio.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>

struct noop_data {
	struct list_head queue;
};

static void noop_merged_requests(struct request_queue *q, struct request *rq,
				 struct request *next)
{
	list_del_init(&next->queuelist);
}

static int noop_dispatch(struct request_queue *q, int force)
{
	struct noop_data *nd = q->elevator->elevator_data;

	if (!list_empty(&nd->queue)) {
		struct request *rq;
		rq = list_entry(nd->queue.next, struct request, queuelist);
		list_del_init(&rq->queuelist);
		elv_dispatch_sort(q, rq);
		return 1;
	}
	return 0;
}

static void noop_add_request(struct request_queue *q, struct request *rq)
{
	struct noop_data *nd = q->elevator->elevator_data;

	list_add_tail(&rq->queuelist, &nd->queue);
}

static int noop_queue_empty(struct request_queue *q)
{
	struct noop_data *nd = q->elevator->elevator_data;

	return list_empty(&nd->queue);
}

static struct request *
noop_former_request(struct request_queue *q, struct request *rq)
{
	struct noop_data *nd = q->elevator->elevator_data;

	if (rq->queuelist.prev == &nd->queue)
		return NULL;
	return list_entry(rq->queuelist.prev, struct request, queuelist);
}

static struct request *
noop_latter_request(struct request_queue *q, struct request *rq)
{
	struct noop_data *nd = q->elevator->elevator_data;

	if (rq->queuelist.next == &nd->queue)
		return NULL;
	return list_entry(rq->queuelist.next, struct request, queuelist);
}

static void *noop_init_queue(struct request_queue *q)
{
	struct noop_data *nd;

	nd = kmalloc_node(sizeof(*nd), GFP_KERNEL, q->node);
	if (!nd)
		return NULL;
	INIT_LIST_HEAD(&nd->queue);
	return nd;
}

static void noop_exit_queue(struct elevator_queue *e)
{
	struct noop_data *nd = e->elevator_data;

	BUG_ON(!list_empty(&nd->queue));
	kfree(nd);
}

static struct elevator_type elevator_noop = {
	.ops = {
		.elevator_merge_req_fn		= noop_merged_requests,
		.elevator_dispatch_fn		= noop_dispatch,
		.elevator_add_req_fn		= noop_add_request,
		.elevator_queue_empty_fn	= noop_queue_empty,
		.elevator_former_req_fn		= noop_former_request,
		.elevator_latter_req_fn		= noop_latter_request,
		.elevator_init_fn		= noop_init_queue,
		.elevator_exit_fn		= noop_exit_queue,
	},
	.elevator_name = "noop",
	.elevator_owner = THIS_MODULE,
};

static int __init noop_init(void)
{
	elv_register(&elevator_noop);

	return 0;
}

static void __exit noop_exit(void)
{
	elv_unregister(&elevator_noop);
}

module_init(noop_init);
module_exit(noop_exit);


MODULE_AUTHOR("Jens Axboe");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("No-op IO scheduler");
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