linux-toradex.git/mm/page-writeback.c, branch v2.6.34

writeback: remove unused nonblocking and congestion checks

2009-12-03T12:54:25+00:00

- no one is calling wb_writeback and write_cache_pages with
  wbc.nonblocking=1 any more
- lumpy pageout will want to do nonblocking writeback without the
  congestion wait

So remove the congestion checks as suggested by Chris.

Signed-off-by: Wu Fengguang 
Cc: Chris Mason 
Cc: Jens Axboe 
Cc: Trond Myklebust 
Cc: Christoph Hellwig 
Cc: Dave Chinner 
Cc: Evgeniy Polyakov 
Cc: Alex Elder 
Signed-off-by: Jens Axboe

writeback: account IO throttling wait as iowait

2009-10-09T10:40:42+00:00

It makes sense to do IOWAIT when someone is blocked
due to IO throttle, as suggested by Kame and Peter.

There is an old comment for not doing IOWAIT on throttle,
however it has been mismatching the code for a long time.

If we stop accounting IOWAIT for 2.6.32, it could be an
undesirable behavior change. So restore the io_schedule.

CC: KAMEZAWA Hiroyuki 
CC: Peter Zijlstra 
Signed-off-by: Wu Fengguang 
Signed-off-by: Jens Axboe

writeback: pass in super_block to bdi_start_writeback()

2009-09-25T22:10:40+00:00

Sometimes we only want to write pages from a specific super_block,
so allow that to be passed in.

This fixes a problem with commit 56a131dcf7ed36c3c6e36bea448b674ea85ed5bb
causing writeback on all super_blocks on a bdi, where we only really
want to sync a specific sb from writeback_inodes_sb().

Signed-off-by: Jens Axboe

Merge branch 'writeback' of git://git.kernel.dk/linux-2.6-block

2009-09-25T16:27:30+00:00

* 'writeback' of git://git.kernel.dk/linux-2.6-block:
  writeback: writeback_inodes_sb() should use bdi_start_writeback()
  writeback: don't delay inodes redirtied by a fast dirtier
  writeback: make the super_block pinning more efficient
  writeback: don't resort for a single super_block in move_expired_inodes()
  writeback: move inodes from one super_block together
  writeback: get rid to incorrect references to pdflush in comments
  writeback: improve readability of the wb_writeback() continue/break logic
  writeback: cleanup writeback_single_inode()
  writeback: kupdate writeback shall not stop when more io is possible
  writeback: stop background writeback when below background threshold
  writeback: balance_dirty_pages() shall write more than dirtied pages
  fs: Fix busyloop in wb_writeback()

writeback: get rid to incorrect references to pdflush in comments

2009-09-25T16:08:25+00:00

Signed-off-by: Jens Axboe

writeback: stop background writeback when below background threshold

2009-09-25T16:08:24+00:00

Treat bdi_start_writeback(0) as a special request to do background write,
and stop such work when we are below the background dirty threshold.

Also simplify the (nr_pages <= 0) checks. Since we already pass in
nr_pages=LONG_MAX for WB_SYNC_ALL and background writes, we don't
need to worry about it being decreased to zero.

Reported-by: Richard Kennedy 
CC: Jan Kara 
Acked-by: Peter Zijlstra 
Signed-off-by: Wu Fengguang 
Signed-off-by: Jens Axboe

writeback: balance_dirty_pages() shall write more than dirtied pages

2009-09-25T16:08:24+00:00

Some filesystem may choose to write much more than ratelimit_pages
before calling balance_dirty_pages_ratelimited_nr(). So it is safer to
determine number to write based on real number of dirtied pages.

Otherwise it is possible that
  loop {
    btrfs_file_write():     dirty 1024 pages
    balance_dirty_pages():  write up to 48 pages (= ratelimit_pages * 1.5)
  }
in which the writeback rate cannot keep up with dirty rate, and the
dirty pages go all the way beyond dirty_thresh.

The increased write_chunk may make the dirtier more bumpy.
So filesystems shall be take care not to dirty too much at
a time (eg. > 4MB) without checking the ratelimit.

Signed-off-by: Wu Fengguang 
Acked-by: Peter Zijlstra 
Signed-off-by: Jens Axboe

Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6

2009-09-24T14:53:22+00:00

* 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6: (21 commits)
  HWPOISON: Enable error_remove_page on btrfs
  HWPOISON: Add simple debugfs interface to inject hwpoison on arbitary PFNs
  HWPOISON: Add madvise() based injector for hardware poisoned pages v4
  HWPOISON: Enable error_remove_page for NFS
  HWPOISON: Enable .remove_error_page for migration aware file systems
  HWPOISON: The high level memory error handler in the VM v7
  HWPOISON: Add PR_MCE_KILL prctl to control early kill behaviour per process
  HWPOISON: shmem: call set_page_dirty() with locked page
  HWPOISON: Define a new error_remove_page address space op for async truncation
  HWPOISON: Add invalidate_inode_page
  HWPOISON: Refactor truncate to allow direct truncating of page v2
  HWPOISON: check and isolate corrupted free pages v2
  HWPOISON: Handle hardware poisoned pages in try_to_unmap
  HWPOISON: Use bitmask/action code for try_to_unmap behaviour
  HWPOISON: x86: Add VM_FAULT_HWPOISON handling to x86 page fault handler v2
  HWPOISON: Add poison check to page fault handling
  HWPOISON: Add basic support for poisoned pages in fault handler v3
  HWPOISON: Add new SIGBUS error codes for hardware poison signals
  HWPOISON: Add support for poison swap entries v2
  HWPOISON: Export some rmap vma locking to outside world
  ...

sysctl: remove "struct file *" argument of ->proc_handler

2009-09-24T14:21:04+00:00

It's unused.

It isn't needed -- read or write flag is already passed and sysctl
shouldn't care about the rest.

It _was_ used in two places at arch/frv for some reason.

Signed-off-by: Alexey Dobriyan 
Cc: David Howells 
Cc: "Eric W. Biederman" 
Cc: Al Viro 
Cc: Ralf Baechle 
Cc: Martin Schwidefsky 
Cc: Ingo Molnar 
Cc: "David S. Miller" 
Cc: James Morris 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: count only reclaimable lru pages

2009-09-22T14:17:30+00:00

global_lru_pages() / zone_lru_pages() can be used in two ways:
- to estimate max reclaimable pages in determine_dirtyable_memory()
- to calculate the slab scan ratio

When swap is full or not present, the anon lru lists are not reclaimable
and also won't be scanned.  So the anon pages shall not be counted in both
usage scenarios.  Also rename to _reclaimable_pages: now they are counting
the possibly reclaimable lru pages.

It can greatly (and correctly) increase the slab scan rate under high
memory pressure (when most file pages have been reclaimed and swap is
full/absent), thus reduce false OOM kills.

Acked-by: Peter Zijlstra 
Reviewed-by: Rik van Riel 
Reviewed-by: Christoph Lameter 
Reviewed-by: Minchan Kim 
Cc: KOSAKI Motohiro 
Signed-off-by: Wu Fengguang 
Acked-by: Johannes Weiner 
Reviewed-by: Minchan Kim 
Reviewed-by: Jesse Barnes 
Cc: David Howells 
Cc: "Li, Ming Chun" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds