diff options
author | Dan Williams <dan.j.williams@intel.com> | 2017-08-24 16:42:48 -0700 |
---|---|---|
committer | Dan Williams <dan.j.williams@intel.com> | 2017-08-31 11:12:13 -0700 |
commit | 5e405595e5bf4c09fab9ca1e7dbe5b62872757b5 (patch) | |
tree | d26852e38cf6c07551d0f42f1e03435e75067583 | |
parent | 8cf037a8b22f71c6659bd0246bfaba9e79766f64 (diff) |
ext4: perform dax_device lookup at mount
The ->iomap_begin() operation is a hot path, so cache the
fs_dax_get_by_host() result at mount time to avoid the incurring the
hash lookup overhead on a per-i/o basis.
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Reviewed-by: Jan Kara <jack@suse.cz>
Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
-rw-r--r-- | fs/ext4/ext4.h | 1 | ||||
-rw-r--r-- | fs/ext4/inode.c | 11 | ||||
-rw-r--r-- | fs/ext4/super.c | 4 |
3 files changed, 8 insertions, 8 deletions
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index a2bb7d2870e4..194e622dc3dd 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1528,6 +1528,7 @@ struct ext4_sb_info { /* Barrier between changing inodes' journal flags and writepages ops. */ struct percpu_rw_semaphore s_journal_flag_rwsem; + struct dax_device *s_daxdev; }; static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index c774bdc22759..16424b5c4e88 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3404,7 +3404,7 @@ static int ext4_releasepage(struct page *page, gfp_t wait) static int ext4_iomap_begin(struct inode *inode, loff_t offset, loff_t length, unsigned flags, struct iomap *iomap) { - struct block_device *bdev; + struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); unsigned int blkbits = inode->i_blkbits; unsigned long first_block = offset >> blkbits; unsigned long last_block = (offset + length - 1) >> blkbits; @@ -3473,12 +3473,8 @@ retry: } iomap->flags = 0; - bdev = inode->i_sb->s_bdev; - iomap->bdev = bdev; - if (blk_queue_dax(bdev->bd_queue)) - iomap->dax_dev = fs_dax_get_by_host(bdev->bd_disk->disk_name); - else - iomap->dax_dev = NULL; + iomap->bdev = inode->i_sb->s_bdev; + iomap->dax_dev = sbi->s_daxdev; iomap->offset = first_block << blkbits; if (ret == 0) { @@ -3511,7 +3507,6 @@ static int ext4_iomap_end(struct inode *inode, loff_t offset, loff_t length, int blkbits = inode->i_blkbits; bool truncate = false; - fs_put_dax(iomap->dax_dev); if (!(flags & IOMAP_WRITE) || (flags & IOMAP_FAULT)) return 0; diff --git a/fs/ext4/super.c b/fs/ext4/super.c index d61a70e2193a..3e58f952eddc 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -951,6 +951,7 @@ static void ext4_put_super(struct super_block *sb) if (sbi->s_chksum_driver) crypto_free_shash(sbi->s_chksum_driver); kfree(sbi->s_blockgroup_lock); + fs_put_dax(sbi->s_daxdev); kfree(sbi); } @@ -3377,6 +3378,7 @@ static void ext4_set_resv_clusters(struct super_block *sb) static int ext4_fill_super(struct super_block *sb, void *data, int silent) { + struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev); char *orig_data = kstrdup(data, GFP_KERNEL); struct buffer_head *bh; struct ext4_super_block *es = NULL; @@ -3399,6 +3401,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO; ext4_group_t first_not_zeroed; + sbi->s_daxdev = dax_dev; if ((data && !orig_data) || !sbi) goto out_free_base; @@ -4378,6 +4381,7 @@ out_fail: out_free_base: kfree(sbi); kfree(orig_data); + fs_put_dax(dax_dev); return err ? err : ret; } |