linux/fs
Zach Brown 5eb6c7a2ab [PATCH] dio: lock refcount operations
The wait_for_more_bios() function name was poorly chosen.  While looking to
clean it up it I noticed that the dio struct refcounting between the bio
completion and dio submission paths was racey.

The bio submission path was simply freeing the dio struct if
atomic_dec_and_test() indicated that it dropped the final reference.

The aio bio completion path was dereferencing its dio struct pointer *after
dropping its reference* based on the remaining number of references.

These two paths could race and result in the aio bio completion path
dereferencing a freed dio, though this was not observed in the wild.

This moves the refcount under the bio lock so that bio completion can drop
its reference and decide to wake all in one atomic step.

Once testing and waking is locked dio_await_one() can test its sleeping
condition and mark itself uninterruptible under the lock.  It gets simpler
and wait_for_more_bios() disappears.

The addition of the interrupt masking spin lock acquiry in dio_bio_submit()
looks alarming.  This lock acquiry existed in that path before the recent
dio completion patch set.  We shouldn't expect significant performance
regression from returning to the behaviour that existed before the
completion clean up work.

This passed 4k block ext3 O_DIRECT fsx and aio-stress on an SMP machine.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Suparna Bhattacharya <suparna@in.ibm.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: <xfs-masters@oss.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-10 09:57:21 -08:00
..
9p [PATCH] 9p: change uses of f_{dentry,vfsmnt} to use f_path 2006-12-08 08:28:43 -08:00
adfs [PATCH] struct path: convert adfs 2006-12-08 08:28:43 -08:00
affs [PATCH] affs: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:43 -08:00
afs [PATCH] rename struct namespace to struct mnt_namespace 2006-12-08 08:28:51 -08:00
autofs [PATCH] autofs: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:43 -08:00
autofs4 [PATCH] autofs4: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:43 -08:00
befs [PATCH] struct path: convert befs 2006-12-08 08:28:44 -08:00
bfs [PATCH] struct path: convert bfs 2006-12-08 08:28:44 -08:00
cifs [PATCH] io-accounting-read-accounting cifs fix 2006-12-10 09:55:41 -08:00
coda [PATCH] struct path: convert coda 2006-12-08 08:28:44 -08:00
configfs [PATCH] configfs: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:43 -08:00
cramfs [PATCH] struct path: convert cramfs 2006-12-08 08:28:44 -08:00
debugfs [PATCH] debugfs: add header file 2006-11-25 13:28:33 -08:00
devpts [PATCH] inode-diet: Eliminate i_blksize from the inode structure 2006-09-27 08:26:18 -07:00
dlm Merge master.kernel.org:/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw 2006-12-07 09:13:20 -08:00
ecryptfs [PATCH] ecryptfs: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:43 -08:00
efs [PATCH] struct path: convert efs 2006-12-08 08:28:45 -08:00
exportfs [PATCH] VFS: Make filldir_t and struct kstat deal in 64-bit inode numbers 2006-10-03 08:03:40 -07:00
ext2 [PATCH] LOG2: Implement a general integer log2 facility in the kernel 2006-12-08 08:28:51 -08:00
ext3 [PATCH] LOG2: Implement a general integer log2 facility in the kernel 2006-12-08 08:28:51 -08:00
ext4 [PATCH] ext4: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:41 -08:00
fat [PATCH] fat: change uses of f_{dentry,vfsmnt} to use f_path 2006-12-08 08:28:41 -08:00
freevxfs [PATCH] struct path: convert freevxfs 2006-12-08 08:28:45 -08:00
fuse [PATCH] struct path: convert fuse 2006-12-08 08:28:45 -08:00
gfs2 [PATCH] struct path: convert gfs2 2006-12-08 08:28:45 -08:00
hfs [PATCH] struct path: convert hfs 2006-12-08 08:28:45 -08:00
hfsplus [PATCH] struct path: convert hfsplus 2006-12-08 08:28:45 -08:00
hostfs [PATCH] struct path: convert hostfs 2006-12-08 08:28:45 -08:00
hpfs [PATCH] struct path: convert hpfs 2006-12-08 08:28:45 -08:00
hppfs [PATCH] struct path: convert hppfs 2006-12-08 08:28:45 -08:00
hugetlbfs [PATCH] struct path: convert hugetlbfs 2006-12-08 08:28:45 -08:00
isofs [PATCH] isofs: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:41 -08:00
jbd [PATCH] make fs/jbd/transaction.c:__journal_temp_unlink_buffer() static 2006-12-07 08:39:40 -08:00
jbd2 [PATCH] jbd2: wait for already submitted t_sync_datalist buffer to complete 2006-12-07 08:39:42 -08:00
jffs [PATCH] struct path: convert jffs 2006-12-08 08:28:46 -08:00
jffs2 [PATCH] struct path: convert jffs2 2006-12-08 08:28:46 -08:00
jfs [PATCH] struct path: convert jfs 2006-12-08 08:28:46 -08:00
lockd [PATCH] struct path: convert lockd 2006-12-08 08:28:47 -08:00
minix [PATCH] struct path: convert minix 2006-12-08 08:28:47 -08:00
msdos [PATCH] fat: add fat_getattr() 2006-11-16 11:43:38 -08:00
ncpfs [PATCH] struct path: convert ncpfs 2006-12-08 08:28:48 -08:00
nfs [PATCH] rename struct namespace to struct mnt_namespace 2006-12-08 08:28:51 -08:00
nfs_common [PATCH] nfs_common endianness annotations 2006-10-20 10:26:41 -07:00
nfsd [PATCH] nfsd: replace kmalloc+memset with kcalloc + simplify NULL check 2006-12-08 08:29:02 -08:00
nls [PATCH] fs: make nls_cp936.c handle some U00XY characters and U20AC correctly 2006-12-07 08:39:46 -08:00
ntfs [PATCH] ntfs: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:42 -08:00
ocfs2 [PATCH] struct path: convert ocfs2 2006-12-08 08:28:48 -08:00
openpromfs [PATCH] struct path: convert openpromfs 2006-12-08 08:28:48 -08:00
partitions [MIPS] Rename SNI_RM200_PCI to just SNI_RM preparing for more RM machines 2006-12-09 01:03:58 +00:00
proc [PATCH] io-accounting: report in procfs 2006-12-10 09:55:41 -08:00
qnx4 [PATCH] struct path: convert qnx4 2006-12-08 08:28:48 -08:00
ramfs [PATCH] struct path: convert ramfs 2006-12-08 08:28:49 -08:00
reiserfs [PATCH] rename struct namespace to struct mnt_namespace 2006-12-08 08:28:51 -08:00
romfs [PATCH] struct path: convert romfs 2006-12-08 08:28:49 -08:00
smbfs [PATCH] struct path: convert smbfs 2006-12-08 08:28:49 -08:00
sysfs [PATCH] sysfs: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:41 -08:00
sysv [PATCH] struct path: convert sysv 2006-12-08 08:28:50 -08:00
udf [PATCH] struct path: convert udf 2006-12-08 08:28:50 -08:00
ufs [PATCH] struct path: convert ufs 2006-12-08 08:28:50 -08:00
vfat [PATCH] fat: add fat_getattr() 2006-11-16 11:43:38 -08:00
xfs [PATCH] dio: only call aio_complete() after returning -EIOCBQUEUED 2006-12-10 09:57:21 -08:00
aio.c [PATCH] aio: remove ki_retried debugging member 2006-12-07 08:39:46 -08:00
attr.c [PATCH] capable/capability.h (fs/) 2006-01-11 18:42:13 -08:00
bad_inode.c [PATCH] Remove readv/writev methods and use aio_read/aio_write instead 2006-10-01 00:39:28 -07:00
binfmt_aout.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
binfmt_elf_fdpic.c [PATCH] add process_session() helper routine 2006-12-08 08:28:51 -08:00
binfmt_elf.c [PATCH] add process_session() helper routine 2006-12-08 08:28:51 -08:00
binfmt_em86.c
binfmt_flat.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
binfmt_misc.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
binfmt_script.c
binfmt_som.c [PARISC] Fix fs/binfmt_som.c 2006-10-04 06:51:26 -06:00
bio.c [PATCH] slab: remove kmem_cache_t 2006-12-07 08:39:25 -08:00
block_dev.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
buffer.c [PATCH] io-accounting: write-cancel accounting 2006-12-10 09:55:41 -08:00
char_dev.c [PATCH] BLOCK: Move extern declarations out of fs/*.c into header files [try #6] 2006-09-30 20:52:18 +02:00
compat_ioctl.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
compat.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
dcache.c [PATCH] dcache: avoid RCU for never-hashed dentries 2006-12-07 08:39:41 -08:00
dcookies.c [PATCH] slab: remove kmem_cache_t 2006-12-07 08:39:25 -08:00
direct-io.c [PATCH] dio: lock refcount operations 2006-12-10 09:57:21 -08:00
dnotify.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
dquot.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
drop_caches.c [PATCH] drop-pagecache 2006-01-08 20:12:40 -08:00
eventpoll.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
exec.c [PATCH] add child reaper to pid_namespace 2006-12-08 08:28:52 -08:00
fcntl.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
fifo.c [PATCH] pipe.c/fifo.c code cleanups 2006-04-11 13:53:33 +02:00
file_table.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
file.c [PATCH] file: kill unnecessary timer in fdtable_defer 2006-12-07 08:39:32 -08:00
filesystems.c [PATCH] Ban register_filesystem(NULL); 2006-09-29 09:18:20 -07:00
fs-writeback.c [PATCH] BLOCK: Remove dependence on existence of blockdev_superblock [try #6] 2006-09-30 20:52:26 +02:00
generic_acl.c [PATCH] Generic infrastructure for acls 2006-09-29 09:18:24 -07:00
inode.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
inotify_user.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
inotify.c [PATCH] severing fs.h, radix-tree.h -> sched.h 2006-12-04 02:00:24 -05:00
internal.h [PATCH] CONFIG_BLOCK internal.h cleanups 2006-09-30 20:52:32 +02:00
ioctl.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
ioprio.c [PATCH] block layer: ioprio_best function fix 2006-10-12 15:09:51 +02:00
Kconfig Fix typos in doc and comments 2006-11-30 05:32:19 +01:00
Kconfig.binfmt [PATCH] frv: suppress configuration of certain features for FRV 2006-01-08 20:13:36 -08:00
libfs.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
locks.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
Makefile [PATCH] fsstack: Introduce fsstack_copy_{attr,inode}_* 2006-12-08 08:28:40 -08:00
mbcache.c [PATCH] slab: remove kmem_cache_t 2006-12-07 08:39:25 -08:00
mpage.c [PATCH] BLOCK: Dissociate generic_writepages() from mpage stuff [try #6] 2006-09-30 20:52:26 +02:00
namei.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
namespace.c [PATCH] rename struct namespace to struct mnt_namespace 2006-12-08 08:28:51 -08:00
nfsctl.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
no-block.c [PATCH] BLOCK: Make it possible to disable the block layer [try #6] 2006-09-30 20:52:31 +02:00
open.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
pipe.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
pnode.c [PATCH] rename struct namespace to struct mnt_namespace 2006-12-08 08:28:51 -08:00
pnode.h [PATCH] rename struct namespace to struct mnt_namespace 2006-12-08 08:28:51 -08:00
posix_acl.c [PATCH] kmemdup: some users 2006-10-01 00:39:19 -07:00
quota_v1.c
quota_v2.c [PATCH] sem2mutex: quota 2006-03-23 07:38:11 -08:00
quota.c [PATCH] BLOCK: Make it possible to disable the block layer [try #6] 2006-09-30 20:52:31 +02:00
read_write.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
read_write.h [PATCH] Remove readv/writev methods and use aio_read/aio_write instead 2006-10-01 00:39:28 -07:00
readdir.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
select.c [PATCH] enforce RLIMIT_NOFILE in poll() 2006-09-29 09:18:23 -07:00
seq_file.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
splice.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
stack.c [PATCH] fsstack: Introduce fsstack_copy_{attr,inode}_* 2006-12-08 08:28:40 -08:00
stat.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
super.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
sync.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
utimes.c [PATCH] severing fs.h, radix-tree.h -> sched.h 2006-12-04 02:00:24 -05:00
xattr_acl.c
xattr.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00