[PATCH] as-iosched: reuse rq for fifo (d4f2f462) · Commits · 戴 / test

block/as-iosched.c

+12 −22

Original line number	Diff line number	Diff line
		@@ -131,8 +131,6 @@ struct as_data {
		unsigned long antic_expire;
		};

		#define list_entry_fifo(ptr) list_entry((ptr), struct as_rq, fifo)

		/*
		* per-request data.
		*/
		@@ -153,12 +151,6 @@ struct as_rq {

		struct io_context io_context; / The submitting task */

		/*
		* expire fifo
		*/
		struct list_head fifo;
		unsigned long expires;

		unsigned int is_sync;
		enum arq_state state;
		};
		@@ -893,7 +885,7 @@ static void as_remove_queued_request(request_queue_t q, struct request rq)
		if (ad->next_arq[data_dir] == arq)
		ad->next_arq[data_dir] = as_find_next_arq(ad, arq);

		list_del_init(&arq->fifo);
		rq_fifo_clear(rq);
		as_del_arq_rb(ad, rq);
		}

		@@ -907,7 +899,7 @@ static void as_remove_queued_request(request_queue_t q, struct request rq)
		*/
		static int as_fifo_expired(struct as_data *ad, int adir)
		{
		struct as_rq *arq;
		struct request *rq;
		long delta_jif;

		delta_jif = jiffies - ad->last_check_fifo[adir];
		@@ -921,9 +913,9 @@ static int as_fifo_expired(struct as_data *ad, int adir)
		if (list_empty(&ad->fifo_list[adir]))
		return 0;

		arq = list_entry_fifo(ad->fifo_list[adir].next);
		rq = rq_entry_fifo(ad->fifo_list[adir].next);

		return time_after(jiffies, arq->expires);
		return time_after(jiffies, rq_fifo_time(rq));
		}

		/*
		@@ -1089,7 +1081,7 @@ static int as_dispatch_request(request_queue_t *q, int force)
		ad->changed_batch = 1;
		}
		ad->batch_data_dir = REQ_SYNC;
		arq = list_entry_fifo(ad->fifo_list[ad->batch_data_dir].next);
		arq = RQ_DATA(rq_entry_fifo(ad->fifo_list[REQ_SYNC].next));
		ad->last_check_fifo[ad->batch_data_dir] = jiffies;
		goto dispatch_request;
		}
		@@ -1129,8 +1121,7 @@ dispatch_request:

		if (as_fifo_expired(ad, ad->batch_data_dir)) {
		fifo_expired:
		arq = list_entry_fifo(ad->fifo_list[ad->batch_data_dir].next);
		BUG_ON(arq == NULL);
		arq = RQ_DATA(rq_entry_fifo(ad->fifo_list[ad->batch_data_dir].next));
		}

		if (ad->changed_batch) {
		@@ -1186,8 +1177,8 @@ static void as_add_request(request_queue_t q, struct request rq)
		/*
		* set expire time (only used for reads) and add to fifo list
		*/
		arq->expires = jiffies + ad->fifo_expire[data_dir];
		list_add_tail(&arq->fifo, &ad->fifo_list[data_dir]);
		rq_set_fifo_time(rq, jiffies + ad->fifo_expire[data_dir]);
		list_add_tail(&rq->queuelist, &ad->fifo_list[data_dir]);

		as_update_arq(ad, arq); /* keep state machine up to date */
		arq->state = AS_RQ_QUEUED;
		@@ -1277,10 +1268,10 @@ static void as_merged_requests(request_queue_t q, struct request req,
		* if anext expires before arq, assign its expire time to arq
		* and move into anext position (anext will be deleted) in fifo
		*/
		if (!list_empty(&arq->fifo) && !list_empty(&anext->fifo)) {
		if (time_before(anext->expires, arq->expires)) {
		list_move(&arq->fifo, &anext->fifo);
		arq->expires = anext->expires;
		if (!list_empty(&req->queuelist) && !list_empty(&next->queuelist)) {
		if (time_before(rq_fifo_time(next), rq_fifo_time(req))) {
		list_move(&req->queuelist, &next->queuelist);
		rq_set_fifo_time(req, rq_fifo_time(next));
		/*
		* Don't copy here but swap, because when anext is
		* removed below, it must contain the unused context
		@@ -1350,7 +1341,6 @@ static int as_set_request(request_queue_t q, struct request rq,
		arq->request = rq;
		arq->state = AS_RQ_PRESCHED;
		arq->io_context = NULL;
		INIT_LIST_HEAD(&arq->fifo);
		rq->elevator_private = arq;
		return 0;
		}

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