linux/fs/fs-writeback.c, branch v3.8

writeback: fix a typo in comment

2012-12-13T01:38:34Z

Signed-off-by: Yan Hong Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

writeback: put unused inodes to LRU after writeback completion

2012-11-27T01:41:24Z

Commit 169ebd90131b ("writeback: Avoid iput() from flusher thread") removed iget-iput pair from inode writeback. As a side effect, inodes that are dirty during iput_final() call won't be ever added to inode LRU (iput_final() doesn't add dirty inodes to LRU and later when the inode is cleaned there's noone to add the inode there). Thus inodes are effectively unreclaimable until someone looks them up again. The practical effect of this bug is limited by the fact that inodes are pinned by a dentry for long enough that the inode gets cleaned. But still the bug can have nasty consequences leading up to OOM conditions under certain circumstances. Following can easily reproduce the problem: for (( i = 0; i < 1000; i++ )); do mkdir $i for (( j = 0; j < 1000; j++ )); do touch $i/$j echo 2 > /proc/sys/vm/drop_caches done done then one needs to run 'sync; ls -lR' to make inodes reclaimable again. We fix the issue by inserting unused clean inodes into the LRU after writeback finishes in inode_sync_complete(). Signed-off-by: Jan Kara Reported-by: OGAWA Hirofumi Cc: Al Viro Cc: OGAWA Hirofumi Cc: Wu Fengguang Cc: Dave Chinner Cc: [3.5+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'writeback-for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux

2012-10-12T01:46:03Z

Pull writeback fixes from Fengguang Wu: "Three trivial writeback fixes" * 'writeback-for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux: CPU hotplug, writeback: Don't call writeback_set_ratelimit() too often during hotplug writeback: correct comment for move_expired_inodes() backing-dev: use kstrto* in preference to simple_strtoul

fs/fs-writeback.c: remove unneccesary parameter of __writeback_single_inode()

2012-10-09T07:23:00Z

The parameter 'wb' is never used in this function. Signed-off-by: Yan Hong Acked-by: Wu Fengguang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

2012-10-07T21:36:39Z

Pull ext4 updates from Ted Ts'o: "The big new feature added this time is supporting online resizing using the meta_bg feature. This allows us to resize file systems which are greater than 16TB. In addition, the speed of online resizing has been improved in general. We also fix a number of races, some of which could lead to deadlocks, in ext4's Asynchronous I/O and online defrag support, thanks to good work by Dmitry Monakhov. There are also a large number of more minor bug fixes and cleanups from a number of other ext4 contributors, quite of few of which have submitted fixes for the first time." * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (69 commits) ext4: fix ext4_flush_completed_IO wait semantics ext4: fix mtime update in nodelalloc mode ext4: fix ext_remove_space for punch_hole case ext4: punch_hole should wait for DIO writers ext4: serialize truncate with owerwrite DIO workers ext4: endless truncate due to nonlocked dio readers ext4: serialize unlocked dio reads with truncate ext4: serialize dio nonlocked reads with defrag workers ext4: completed_io locking cleanup ext4: fix unwritten counter leakage ext4: give i_aiodio_unwritten a more appropriate name ext4: ext4_inode_info diet ext4: convert to use leXX_add_cpu() ext4: ext4_bread usage audit fs: reserve fallocate flag codepoint ext4: remove redundant offset check in mext_check_arguments() ext4: don't clear orphan list on ro mount with errors jbd2: fix assertion failure in commit code due to lacking transaction credits ext4: release donor reference when EXT4_IOC_MOVE_EXT ioctl fails ext4: enable FITRIM ioctl on bigalloc file system ...

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial

2012-10-01T16:06:36Z

Pull the trivial tree from Jiri Kosina: "Tiny usual fixes all over the place" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (34 commits) doc: fix old config name of kprobetrace fs/fs-writeback.c: cleanup riteback_sb_inodes kerneldoc btrfs: fix the commment for the action flags in delayed-ref.h btrfs: fix trivial typo for the comment of BTRFS_FREE_INO_OBJECTID vfs: fix kerneldoc for generic_fh_to_parent() treewide: fix comment/printk/variable typos ipr: fix small coding style issues doc: fix broken utf8 encoding nfs: comment fix platform/x86: fix asus_laptop.wled_type module parameter mfd: printk/comment fixes doc: getdelays.c: remember to close() socket on error in create_nl_socket() doc: aliasing-test: close fd on write error mmc: fix comment typos dma: fix comments spi: fix comment/printk typos in spi Coccinelle: fix typo in memdup_user.cocci tmiofb: missing NULL pointer checks tools: perf: Fix typo in tools/perf tools/testing: fix comment / output typos ...

fs/fs-writeback.c: cleanup riteback_sb_inodes kerneldoc

2012-09-21T10:04:36Z

Argument @only_this_sb has been removed. Signed-off-by: Liu Bo Signed-off-by: Jiri Kosina

ext4: fix potential deadlock in ext4_nonda_switch()

2012-09-20T02:42:36Z

In ext4_nonda_switch(), if the file system is getting full we used to call writeback_inodes_sb_if_idle(). The problem is that we can be holding i_mutex already, and this causes a potential deadlock when writeback_inodes_sb_if_idle() when it tries to take s_umount. (See lockdep output below). As it turns out we don't need need to hold s_umount; the fact that we are in the middle of the write(2) system call will keep the superblock pinned. Unfortunately writeback_inodes_sb() checks to make sure s_umount is taken, and the VFS uses a different mechanism for making sure the file system doesn't get unmounted out from under us. The simplest way of dealing with this is to just simply grab s_umount using a trylock, and skip kicking the writeback flusher thread in the very unlikely case that we can't take a read lock on s_umount without blocking. Also, we now check the cirteria for kicking the writeback thread before we decide to whether to fall back to non-delayed writeback, so if there are any outstanding delayed allocation writes, we try to get them resolved as soon as possible. [ INFO: possible circular locking dependency detected ] 3.6.0-rc1-00042-gce894ca #367 Not tainted ------------------------------------------------------- dd/8298 is trying to acquire lock: (&type->s_umount_key#18){++++..}, at: [] writeback_inodes_sb_if_idle+0x28/0x46 but task is already holding lock: (&sb->s_type->i_mutex_key#8){+.+...}, at: [] generic_file_aio_write+0x5f/0xd3 which lock already depends on the new lock. 2 locks held by dd/8298: #0: (sb_writers#2){.+.+.+}, at: [] generic_file_aio_write+0x56/0xd3 #1: (&sb->s_type->i_mutex_key#8){+.+...}, at: [] generic_file_aio_write+0x5f/0xd3 stack backtrace: Pid: 8298, comm: dd Not tainted 3.6.0-rc1-00042-gce894ca #367 Call Trace: [] ? console_unlock+0x345/0x372 [] print_circular_bug+0x190/0x19d [] __lock_acquire+0x86d/0xb6c [] ? mark_held_locks+0x5c/0x7b [] lock_acquire+0x66/0xb9 [] ? writeback_inodes_sb_if_idle+0x28/0x46 [] down_read+0x28/0x58 [] ? writeback_inodes_sb_if_idle+0x28/0x46 [] writeback_inodes_sb_if_idle+0x28/0x46 [] ext4_nonda_switch+0xe1/0xf4 [] ext4_da_write_begin+0x27/0x193 [] generic_file_buffered_write+0xc8/0x1bb [] __generic_file_aio_write+0x1dd/0x205 [] generic_file_aio_write+0x78/0xd3 [] ext4_file_write+0x480/0x4a6 [] ? __lock_acquire+0x41e/0xb6c [] ? sched_clock_cpu+0x11a/0x13e [] ? trace_hardirqs_off+0xb/0xd [] ? local_clock+0x37/0x4e [] do_sync_write+0x67/0x9d [] ? wait_on_retry_sync_kiocb+0x44/0x44 [] vfs_write+0x7b/0xe6 [] sys_write+0x3b/0x64 [] syscall_call+0x7/0xb Signed-off-by: "Theodore Ts'o" Cc: stable@vger.kernel.org

writeback: correct comment for move_expired_inodes()

2012-09-11T00:29:50Z

The function scans @delaying_queue and stops at the first inode whose dirtied_when is after *work->older_than_this. So the expired ones being moved are those before *work->older_than_this. Correct the comment here. Reviewed-by: Jan Kara Signed-off-by: Wang Sheng-Hui

mm: prepare for removal of obsolete /proc/sys/vm/nr_pdflush_threads

2012-08-01T01:42:40Z

Since per-BDI flusher threads were introduced in 2.6, the pdflush mechanism is not used any more. But the old interface exported through /proc/sys/vm/nr_pdflush_threads still exists and is obviously useless. For back-compatibility, printk warning information and return 2 to notify the users that the interface is removed. Signed-off-by: Wanpeng Li Cc: Wu Fengguang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds