linux.git/mm/memcontrol.c, branch v2.6.39

Fix common misspellings

2011-03-31T14:26:23+00:00

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi

memcg: fix leak on wrong LRU with FUSE

2011-03-24T02:46:33+00:00

fs/fuse/dev.c::fuse_try_move_page() does

   (1) remove a page by ->steal()
   (2) re-add the page to page cache
   (3) link the page to LRU if it was not on LRU at (1)

This implies the page is _on_ LRU when it's added to radix-tree.  So, the
page is added to memory cgroup while it's on LRU.  because LRU is lazy and
no one flushs it.

This is the same behavior as SwapCache and needs special care as
 - remove page from LRU before overwrite pc->mem_cgroup.
 - add page to LRU after overwrite pc->mem_cgroup.

And we need to taking care of pagevec.

If PageLRU(page) is set before we add PCG_USED bit, the page will not be
added to memcg's LRU (in short period).  So, regardlress of PageLRU(page)
value before commit_charge(), we need to check PageLRU(page) after
commit_charge().

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=30432

Signed-off-by: KAMEZAWA Hiroyuki 
Reviewed-by: Johannes Weiner 
Acked-by: Daisuke Nishimura 
Cc: Miklos Szeredi 
Cc: Balbir Singh 
Reported-by: Daniel Poelzleithner 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/memcontrol.c: suppress uninitialized-var warning with older gcc's

2011-03-24T02:46:32+00:00

mm/memcontrol.c: In function 'mem_cgroup_force_empty':
mm/memcontrol.c:2280: warning: 'flags' may be used uninitialized in this function

It's a false positive.

Cc: Balbir Singh 
Cc: Daisuke Nishimura 
Cc: Greg Thelen 
Cc: Johannes Weiner 
Cc: KAMEZAWA Hiroyuki 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

memcg: use native word page statistics counters

2011-03-24T02:46:31+00:00

The statistic counters are in units of pages, there is no reason to make
them 64-bit wide on 32-bit machines.

Make them native words.  Since they are signed, this leaves 31 bit on
32-bit machines, which can represent roughly 8TB assuming a page size of
4k.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Johannes Weiner 
Signed-off-by: Greg Thelen 
Acked-by: KAMEZAWA Hiroyuki 
Acked-by: Balbir Singh 
Cc: Daisuke Nishimura 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

memcg: break out event counters from other stats

2011-03-24T02:46:31+00:00

For increasing and decreasing per-cpu cgroup usage counters it makes sense
to use signed types, as single per-cpu values might go negative during
updates.  But this is not the case for only-ever-increasing event
counters.

All the counters have been signed 64-bit so far, which was enough to count
events even with the sign bit wasted.

This patch:
- divides s64 counters into signed usage counters and unsigned
  monotonically increasing event counters.
- converts unsigned event counters into 'unsigned long' rather than
  'u64'.  This matches the type used by the /proc/vmstat event counters.

The next patch narrows the signed usage counters type (on 32-bit CPUs,
that is).

Signed-off-by: Johannes Weiner 
Signed-off-by: Greg Thelen 
Acked-by: KAMEZAWA Hiroyuki 
Acked-by: Balbir Singh 
Cc: Daisuke Nishimura 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

memcg: unify charge/uncharge quantities to units of pages

2011-03-24T02:46:30+00:00

There is no clear pattern when we pass a page count and when we pass a
byte count that is a multiple of PAGE_SIZE.

We never charge or uncharge subpage quantities, so convert it all to page
counts.

Signed-off-by: Johannes Weiner 
Acked-by: KAMEZAWA Hiroyuki 
Cc: Daisuke Nishimura 
Cc: Balbir Singh 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

memcg: convert uncharge batching from bytes to page granularity

2011-03-24T02:46:30+00:00

We never uncharge subpage quantities.

Signed-off-by: Johannes Weiner 
Acked-by: KAMEZAWA Hiroyuki 
Cc: Daisuke Nishimura 
Cc: Balbir Singh 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

memcg: convert per-cpu stock from bytes to page granularity

2011-03-24T02:46:29+00:00

We never keep subpage quantities in the per-cpu stock.

Signed-off-by: Johannes Weiner 
Acked-by: KAMEZAWA Hiroyuki 
Cc: Daisuke Nishimura 
Cc: Balbir Singh 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

memcg: keep only one charge cancelling function

2011-03-24T02:46:29+00:00

We have two charge cancelling functions: one takes a page count, the other
a page size.  The second one just divides the parameter by PAGE_SIZE and
then calls the first one.  This is trivial, no need for an extra function.

Signed-off-by: Johannes Weiner 
Acked-by: KAMEZAWA Hiroyuki 
Cc: Daisuke Nishimura 
Cc: Balbir Singh 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

memcg: remove memcg->reclaim_param_lock

2011-03-24T02:46:29+00:00

The reclaim_param_lock is only taken around single reads and writes to
integer variables and is thus superfluous.  Drop it.

Signed-off-by: Johannes Weiner 
Acked-by: KAMEZAWA Hiroyuki 
Cc: Daisuke Nishimura 
Cc: Balbir Singh 
Reviewed-by: Minchan Kim 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds