kernel_optimize_test/fs
Fengguang Wu 2e6883bdf4 writeback: introduce writeback_control.more_io to indicate more io
After making dirty a 100M file, the normal behavior is to start the writeback
for all data after 30s delays.  But sometimes the following happens instead:

	- after 30s:    ~4M
	- after 5s:     ~4M
	- after 5s:     all remaining 92M

Some analyze shows that the internal io dispatch queues goes like this:

		s_io            s_more_io
		-------------------------
	1)	100M,1K         0
	2)	1K              96M
	3)	0               96M

1) initial state with a 100M file and a 1K file
2) 4M written, nr_to_write <= 0, so write more
3) 1K written, nr_to_write > 0, no more writes(BUG)

nr_to_write > 0 in (3) fools the upper layer to think that data have all been
written out.  The big dirty file is actually still sitting in s_more_io.  We
cannot simply splice s_more_io back to s_io as soon as s_io becomes empty, and
let the loop in generic_sync_sb_inodes() continue: this may starve newly
expired inodes in s_dirty.  It is also not an option to draw inodes from both
s_more_io and s_dirty, an let the loop go on: this might lead to live locks,
and might also starve other superblocks in sync time(well kupdate may still
starve some superblocks, that's another bug).

We have to return when a full scan of s_io completes.  So nr_to_write > 0 does
not necessarily mean that "all data are written".  This patch introduces a
flag writeback_control.more_io to indicate this situation.  With it the big
dirty file no longer has to wait for the next kupdate invocation 5s later.

Cc: David Chinner <dgc@sgi.com>
Cc: Ken Chen <kenchen@google.com>
Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:43:02 -07:00
..
9p
adfs Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
affs fs: mark nibblemap const 2007-10-17 08:42:47 -07:00
afs KEYS: Make request_key() and co fundamentally asynchronous 2007-10-17 08:42:57 -07:00
autofs
autofs4 fs/autofs4/inode.c: kmalloc + memset conversion to kzalloc 2007-10-17 08:42:50 -07:00
befs Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
bfs Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
cifs Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
coda Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
configfs mm: bdi init hooks 2007-10-17 08:42:45 -07:00
cramfs cramfs: error message about endianess 2007-10-17 08:42:53 -07:00
debugfs docbook: fix filesystems content 2007-10-15 17:56:36 -07:00
devpts
dlm menuconfig: transform NLS and DLM menus 2007-10-17 08:43:00 -07:00
ecryptfs Clean up duplicate includes in fs/ecryptfs/ 2007-10-17 08:42:48 -07:00
efs Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
exportfs
ext2 ext2/4: use is_power_of_2() 2007-10-17 08:42:53 -07:00
ext3 ext3: lighten up resize transaction requirements 2007-10-17 08:43:01 -07:00
ext4 Fix f_version type: should be u64 instead of unsigned long 2007-10-17 08:42:53 -07:00
fat Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
freevxfs
fuse Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
gfs2 fs: correct SuS compliance for open of large file without options 2007-10-17 08:43:01 -07:00
hfs Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
hfsplus Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
hostfs uml: fix hostfs style 2007-10-16 09:43:07 -07:00
hpfs Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
hppfs
hugetlbfs Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
isofs fs/isofs/namei.c: Remove uninitialized local vars warning 2007-10-17 08:42:58 -07:00
jbd Group short-lived and reclaimable kernel allocations 2007-10-16 09:43:00 -07:00
jbd2
jffs2 Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
jfs Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
lockd
minix limit minixfs printks on corrupted dir i_size 2007-10-17 08:42:53 -07:00
msdos
ncpfs Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
nfs Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
nfs_common
nfsd fs/nfsd/export.c: make 3 functions static 2007-10-16 09:43:10 -07:00
nls menuconfig: transform NLS and DLM menus 2007-10-17 08:43:00 -07:00
ntfs writeback: fix ntfs with sb_has_dirty_inodes() 2007-10-17 08:43:02 -07:00
ocfs2 Fix f_version type: should be u64 instead of unsigned long 2007-10-17 08:42:53 -07:00
openpromfs Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
partitions fs/partitions/sun.c endianness annotations 2007-10-14 12:41:51 -07:00
proc Don't truncate /proc/PID/environ at 4096 characters 2007-10-17 08:43:00 -07:00
qnx4 Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
ramfs Remove valueless definition of hard-selected RAMFS option 2007-10-17 08:42:56 -07:00
reiserfs reiserfs: do not repair wrong journal params 2007-10-17 08:43:01 -07:00
romfs fs/romfs/inode.c: trivial improvements 2007-10-17 08:42:47 -07:00
smbfs Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
sysfs spin_lock_unlocked cleanups 2007-10-17 08:43:01 -07:00
sysv Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
udf fs/udf/balloc.c: mark a variable as uninitialized_var() 2007-10-17 08:43:00 -07:00
ufs ufs: Fix mount check in ufs_fill_super() 2007-10-17 08:42:51 -07:00
vfat
xfs writeback: remove pages_skipped accounting in __block_write_full_page() 2007-10-17 08:43:02 -07:00
aio.c aio: account I/O wait time properly 2007-10-17 08:42:53 -07:00
anon_inodes.c anon-inodes use open coded atomic_inc for the shared inode 2007-10-17 08:43:00 -07:00
attr.c
bad_inode.c
binfmt_aout.c core_pattern: ignore RLIMIT_CORE if core_pattern is a pipe 2007-10-17 08:42:50 -07:00
binfmt_elf_fdpic.c core_pattern: ignore RLIMIT_CORE if core_pattern is a pipe 2007-10-17 08:42:50 -07:00
binfmt_elf.c Break ELF_PLATFORM and stack pointer randomization dependency 2007-10-17 08:43:01 -07:00
binfmt_em86.c
binfmt_flat.c binfmt_flat: warning fixes 2007-10-17 08:42:54 -07:00
binfmt_misc.c
binfmt_script.c
binfmt_som.c core_pattern: ignore RLIMIT_CORE if core_pattern is a pipe 2007-10-17 08:42:50 -07:00
bio.c bio: make freeing of ->bi_io_vec conditional in bio_free() 2007-10-16 11:03:52 +02:00
block_dev.c Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
buffer.c writeback: remove pages_skipped accounting in __block_write_full_page() 2007-10-17 08:43:02 -07:00
char_dev.c mm: bdi init hooks 2007-10-17 08:42:45 -07:00
compat_ioctl.c Clean up duplicate includes in fs/ 2007-10-17 08:42:48 -07:00
compat.c
dcache.c vfs: use the predefined d_unhashed inline function instead 2007-10-17 08:43:00 -07:00
dcookies.c
direct-io.c remove ZERO_PAGE 2007-10-16 09:42:53 -07:00
dnotify.c
dquot.c quota: send messages via netlink 2007-10-17 08:42:56 -07:00
drop_caches.c
eventfd.c
eventpoll.c
exec.c exec: RT sub-thread can livelock and monopolize CPU on exec 2007-10-17 08:42:54 -07:00
fcntl.c F_DUPFD_CLOEXEC implementation 2007-10-17 08:43:01 -07:00
fifo.c
file_table.c fs: use kmem_cache_zalloc instead 2007-10-17 08:42:48 -07:00
file.c
filesystems.c
fs-writeback.c writeback: introduce writeback_control.more_io to indicate more io 2007-10-17 08:43:02 -07:00
generic_acl.c
inode.c fs: remove the unused mempages parameter 2007-10-17 08:42:49 -07:00
inotify_user.c change inotifyfs magic as the same magic is used for futexfs 2007-10-17 08:43:00 -07:00
inotify.c
internal.h
ioctl.c
ioprio.c
Kconfig menuconfig: transform Network Filesystems menu 2007-10-17 08:43:00 -07:00
Kconfig.binfmt
libfs.c make fs/libfs.c:simple_commit_write() static 2007-10-17 08:42:53 -07:00
locks.c Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
Makefile Remove valueless definition of hard-selected RAMFS option 2007-10-17 08:42:56 -07:00
mbcache.c
mpage.c mm: buffered write cleanup 2007-10-16 09:42:54 -07:00
namei.c fix execute checking in permission() 2007-10-17 08:42:52 -07:00
namespace.c fs: remove the unused mempages parameter 2007-10-17 08:42:49 -07:00
nfsctl.c
no-block.c
open.c fs: correct SuS compliance for open of large file without options 2007-10-17 08:43:01 -07:00
pipe.c sched: affine sync wakeups 2007-10-15 17:00:19 +02:00
pnode.c
pnode.h
posix_acl.c
quota_v1.c
quota_v2.c
quota.c
read_write.c
read_write.h
readdir.c
select.c Use ERESTART_RESTARTBLOCK if poll() is interrupted by a signal 2007-10-17 08:42:53 -07:00
seq_file.c
signalfd.c rename signalfd_siginfo fields 2007-10-17 08:43:01 -07:00
splice.c Merge branch 'for-linus' of git://git.kernel.dk/data/git/linux-2.6-block 2007-10-16 10:09:16 -07:00
stack.c
stat.c
super.c writeback: fix periodic superblock dirty inode flushing 2007-10-17 08:43:02 -07:00
sync.c
timerfd.c
utimes.c VFS: check nanoseconds in utimensat 2007-10-17 08:42:52 -07:00
xattr_acl.c
xattr.c