Commit b414579f authored by NeilBrown's avatar NeilBrown
Browse files

md: raid0: remove ->dev pointer from strip_zone structure 



If we treat conf->devlist more like a 2 dimensional array,
we can get the devlist for a particular zone simply by indexing
that array, so we don't need to store the pointers to subarrays
in strip_zone.  This makes strip_zone smaller and so (hopefully)
searches faster.

Signed-of-by: default avatarNeilBrown <neilb@suse.de>
parent 49f357a2

drivers/md/raid0.c

+11 −10
Original line number Diff line number Diff line
@@ -27,7 +27,7 @@ static void raid0_unplug(struct request_queue *q) 
{

	mddev_t *mddev = q->queuedata;

	raid0_conf_t *conf = mddev_to_conf(mddev);

	mdk_rdev_t **devlist = conf->strip_zone[0].dev;

	mdk_rdev_t **devlist = conf->devlist;

	int i;



	for (i=0; i<mddev->raid_disks; i++) {
@@ -41,7 +41,7 @@ static int raid0_congested(void *data, int bits) 
{

	mddev_t *mddev = data;

	raid0_conf_t *conf = mddev_to_conf(mddev);

	mdk_rdev_t **devlist = conf->strip_zone[0].dev;

	mdk_rdev_t **devlist = conf->devlist;

	int i, ret = 0;



	for (i = 0; i < mddev->raid_disks && !ret ; i++) {
@@ -56,7 +56,7 @@ static int create_strip_zones(mddev_t *mddev) 
{

	int i, c, j, err;

	sector_t curr_zone_end, sectors;

	mdk_rdev_t *smallest, *rdev1, *rdev2, *rdev;

	mdk_rdev_t *smallest, *rdev1, *rdev2, *rdev, **dev;

	struct strip_zone *zone;

	int cnt;

	char b[BDEVNAME_SIZE];
@@ -115,7 +115,7 @@ static int create_strip_zones(mddev_t *mddev) 
	zone = &conf->strip_zone[0];

	cnt = 0;

	smallest = NULL;

	zone->dev = conf->devlist;

	dev = conf->devlist;

	err = -EINVAL;

	list_for_each_entry(rdev1, &mddev->disks, same_set) {

		int j = rdev1->raid_disk;
@@ -125,12 +125,12 @@ static int create_strip_zones(mddev_t *mddev) 
				"aborting!\n", j);

			goto abort;

		}

		if (zone->dev[j]) {

		if (dev[j]) {

			printk(KERN_ERR "raid0: multiple devices for %d - "

				"aborting!\n", j);

			goto abort;

		}

		zone->dev[j] = rdev1;

		dev[j] = rdev1;



		blk_queue_stack_limits(mddev->queue,

				       rdev1->bdev->bd_disk->queue);
@@ -161,7 +161,7 @@ static int create_strip_zones(mddev_t *mddev) 
	for (i = 1; i < conf->nr_strip_zones; i++)

	{

		zone = conf->strip_zone + i;

		zone->dev = conf->strip_zone[i-1].dev + mddev->raid_disks;

		dev = conf->devlist + i * mddev->raid_disks;



		printk(KERN_INFO "raid0: zone %d\n", i);

		zone->dev_start = smallest->sectors;
@@ -170,7 +170,7 @@ static int create_strip_zones(mddev_t *mddev) 


		for (j=0; j<cnt; j++) {

			char b[BDEVNAME_SIZE];

			rdev = conf->strip_zone[0].dev[j];

			rdev = conf->devlist[j];

			printk(KERN_INFO "raid0: checking %s ...",

				bdevname(rdev->bdev, b));

			if (rdev->sectors <= zone->dev_start) {
@@ -178,7 +178,7 @@ static int create_strip_zones(mddev_t *mddev) 
				continue;

			}

			printk(KERN_INFO " contained as device %d\n", c);

			zone->dev[c] = rdev;

			dev[c] = rdev;

			c++;

			if (!smallest || rdev->sectors < smallest->sectors) {

				smallest = rdev;
@@ -383,7 +383,8 @@ static int raid0_make_request (struct request_queue *q, struct bio *bio) 
		chunk = x;



		x = sector >> chunksect_bits;

		tmp_dev = zone->dev[sector_div(x, zone->nb_dev)];

		tmp_dev = conf->devlist[(zone - conf->strip_zone)*mddev->raid_disks

					+ sector_div(x, zone->nb_dev)];

	}

	rsect = (chunk << chunksect_bits) + zone->dev_start + sect_in_chunk;

drivers/md/raid0.h

+0 −1
Original line number Diff line number Diff line
@@ -6,7 +6,6 @@ struct strip_zone 
	sector_t zone_end;	/* Start of the next zone (in sectors) */

	sector_t dev_start;	/* Zone offset in real dev (in sectors) */

	int nb_dev;		/* # of devices attached to the zone */

	mdk_rdev_t **dev;	/* Devices attached to the zone */

};



struct raid0_private_data

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