hpfs: implement prefetch to improve performance
This patch implements prefetch to improve performance. It helps mostly
when scanning the bitmaps to calculate free space.
Signed-off-by: Mikulas Patocka <mpatocka@artax.karlin.mff.cuni.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/hpfs/hpfs_fn.h b/fs/hpfs/hpfs_fn.h
index b7ae286..1b39863 100644
--- a/fs/hpfs/hpfs_fn.h
+++ b/fs/hpfs/hpfs_fn.h
@@ -27,8 +27,9 @@
#define ALLOC_FWD_MAX 128
#define ALLOC_M 1
#define FNODE_RD_AHEAD 16
-#define ANODE_RD_AHEAD 16
-#define DNODE_RD_AHEAD 4
+#define ANODE_RD_AHEAD 0
+#define DNODE_RD_AHEAD 72
+#define COUNT_RD_AHEAD 62
#define FREE_DNODES_ADD 58
#define FREE_DNODES_DEL 29
@@ -207,6 +208,7 @@
/* buffer.c */
+void hpfs_prefetch_sectors(struct super_block *, unsigned, int);
void *hpfs_map_sector(struct super_block *, unsigned, struct buffer_head **, int);
void *hpfs_get_sector(struct super_block *, unsigned, struct buffer_head **);
void *hpfs_map_4sectors(struct super_block *, unsigned, struct quad_buffer_head *, int);
@@ -271,6 +273,7 @@
__le32 *hpfs_map_dnode_bitmap(struct super_block *, struct quad_buffer_head *);
__le32 *hpfs_map_bitmap(struct super_block *, unsigned, struct quad_buffer_head *, char *);
+void hpfs_prefetch_bitmap(struct super_block *, unsigned);
unsigned char *hpfs_load_code_page(struct super_block *, secno);
__le32 *hpfs_load_bitmap_directory(struct super_block *, secno bmp);
struct fnode *hpfs_map_fnode(struct super_block *s, ino_t, struct buffer_head **);