Commit 8c3e3582 authored by David Sterba's avatar David Sterba
Browse files

btrfs: use u8 for raid_array members 



The raid_attr table is now 7 * 56 = 392 bytes long, consisting of just
small numbers so we don't have to use ints. New size is 7 * 32 = 224,
saving 3 cachelines.

Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 946c9256

fs/btrfs/disk-io.c

+2 −2
Original line number Diff line number Diff line
@@ -3704,7 +3704,7 @@ int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags) 


	if ((flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 ||

	    (flags & BTRFS_AVAIL_ALLOC_BIT_SINGLE))

		min_tolerated = min(min_tolerated,

		min_tolerated = min_t(int, min_tolerated,

				    btrfs_raid_array[BTRFS_RAID_SINGLE].

				    tolerated_failures);
@@ -3713,7 +3713,7 @@ int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags) 
			continue;

		if (!(flags & btrfs_raid_array[raid_type].bg_flag))

			continue;

		min_tolerated = min(min_tolerated,

		min_tolerated = min_t(int, min_tolerated,

				    btrfs_raid_array[raid_type].

				    tolerated_failures);

	}

fs/btrfs/volumes.h

+9 −9
Original line number Diff line number Diff line
@@ -336,16 +336,16 @@ struct btrfs_device_info { 
};



struct btrfs_raid_attr {

	int sub_stripes;	/* sub_stripes info for map */

	int dev_stripes;	/* stripes per dev */

	int devs_max;		/* max devs to use */

	int devs_min;		/* min devs needed */

	int tolerated_failures; /* max tolerated fail devs */

	int devs_increment;	/* ndevs has to be a multiple of this */

	int ncopies;		/* how many copies to data has */

	int nparity;		/* number of stripes worth of bytes to store

	u8 sub_stripes;		/* sub_stripes info for map */

	u8 dev_stripes;		/* stripes per dev */

	u8 devs_max;		/* max devs to use */

	u8 devs_min;		/* min devs needed */

	u8 tolerated_failures;	/* max tolerated fail devs */

	u8 devs_increment;	/* ndevs has to be a multiple of this */

	u8 ncopies;		/* how many copies to data has */

	u8 nparity;		/* number of stripes worth of bytes to store

				 * parity information */

	int mindev_error;	/* error code if min devs requisite is unmet */

	u8 mindev_error;	/* error code if min devs requisite is unmet */

	const char raid_name[8]; /* name of the raid */

	u64 bg_flag;		/* block group flag of the raid */

};