dc58266385
The number of strip_zones of a raid0 array is bounded by the number of drives in the array and is in fact much smaller for typical setups. For example, any raid0 array containing identical disks will have only a single strip_zone. Therefore, the hash tables which are used for quickly finding the strip_zone that holds a particular sector are of questionable value and add quite a bit of unnecessary complexity. This patch replaces the hash table lookup by equivalent code which simply loops over all strip zones to find the zone that holds the given sector. In order to make this loop as fast as possible, the zone->start field of struct strip_zone has been renamed to zone_end, and it now stores the beginning of the next zone in sectors. This allows to save one addition in the loop. Subsequent cleanup patches will remove the hash table structure. Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
29 lines
772 B
C
29 lines
772 B
C
#ifndef _RAID0_H
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#define _RAID0_H
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struct strip_zone
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{
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sector_t zone_end; /* Start of the next zone (in sectors) */
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sector_t dev_start; /* Zone offset in real dev (in sectors) */
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sector_t sectors; /* Zone size in sectors */
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int nb_dev; /* # of devices attached to the zone */
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mdk_rdev_t **dev; /* Devices attached to the zone */
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};
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struct raid0_private_data
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{
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struct strip_zone **hash_table; /* Table of indexes into strip_zone */
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struct strip_zone *strip_zone;
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mdk_rdev_t **devlist; /* lists of rdevs, pointed to by strip_zone->dev */
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int nr_strip_zones;
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sector_t spacing;
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int sector_shift; /* shift this before divide by spacing */
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};
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typedef struct raid0_private_data raid0_conf_t;
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#define mddev_to_conf(mddev) ((raid0_conf_t *) mddev->private)
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#endif
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