kernel_optimize_test/fs/isofs
jan Blunck ca572727db fs/: do not fallback to default_llseek() when readdir() uses BKL
Do not use the fallback default_llseek() if the readdir operation of the
filesystem still uses the big kernel lock.

Since llseek() modifies
file->f_pos of the directory directly it may need locking to not confuse
readdir which usually uses file->f_pos directly as well

Since the special characteristics of the BKL (unlocked on schedule) are
not necessary in this case, the inode mutex can be used for locking as
provided by generic_file_llseek().  This is only possible since all
filesystems, except reiserfs, either use a directory as a flat file or
with disk address offsets.  Reiserfs on the other hand uses a 32bit hash
off the filename as the offset so generic_file_llseek() can get used as
well since the hash is always smaller than sb->s_maxbytes (= (512 << 32) -
blocksize).

Signed-off-by: Jan Blunck <jblunck@suse.de>
Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Anders Larsen <al@alarsen.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:56 -07:00
..
compress.c zisofs: Implement reading of compressed files when PAGE_CACHE_SIZE > compress block size 2009-12-10 15:02:49 +01:00
dir.c fs/: do not fallback to default_llseek() when readdir() uses BKL 2010-05-27 09:12:56 -07:00
export.c nfs: new subdir Documentation/filesystems/nfs 2009-10-27 19:34:04 -04:00
inode.c fs: Make unload_nls() NULL pointer safe 2009-09-24 07:47:42 -04:00
isofs.h isofs: cleanup mount option processing 2009-06-18 13:03:45 -07:00
joliet.c NLS: update handling of Unicode 2009-06-15 21:44:43 -07:00
Kconfig fs/Kconfig: move iso9660, udf out 2009-01-22 13:15:55 +03:00
Makefile
namei.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
rock.c zisofs: Implement reading of compressed files when PAGE_CACHE_SIZE > compress block size 2009-12-10 15:02:49 +01:00
rock.h [PATCH] rock: rename union members 2005-06-21 19:07:38 -07:00
util.c
zisofs.h [PATCH] mark address_space_operations const 2006-06-28 14:59:04 -07:00