firefly-linux-kernel-4.4.55.git
12 years agomm: replace vma prio_tree with an interval tree
Michel Lespinasse [Mon, 8 Oct 2012 23:31:25 +0000 (16:31 -0700)]
mm: replace vma prio_tree with an interval tree

Implement an interval tree as a replacement for the VMA prio_tree.  The
algorithms are similar to lib/interval_tree.c; however that code can't be
directly reused as the interval endpoints are not explicitly stored in the
VMA.  So instead, the common algorithm is moved into a template and the
details (node type, how to get interval endpoints from the node, etc) are
filled in using the C preprocessor.

Once the interval tree functions are available, using them as a
replacement to the VMA prio tree is a relatively simple, mechanical job.

Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: add prio tree and interval tree tests
Michel Lespinasse [Mon, 8 Oct 2012 23:31:23 +0000 (16:31 -0700)]
rbtree: add prio tree and interval tree tests

Patch 1 implements support for interval trees, on top of the augmented
rbtree API. It also adds synthetic tests to compare the performance of
interval trees vs prio trees. Short answers is that interval trees are
slightly faster (~25%) on insert/erase, and much faster (~2.4 - 3x)
on search. It is debatable how realistic the synthetic test is, and I have
not made such measurements yet, but my impression is that interval trees
would still come out faster.

Patch 2 uses a preprocessor template to make the interval tree generic,
and uses it as a replacement for the vma prio_tree.

Patch 3 takes the other prio_tree user, kmemleak, and converts it to use
a basic rbtree. We don't actually need the augmented rbtree support here
because the intervals are always non-overlapping.

Patch 4 removes the now-unused prio tree library.

Patch 5 proposes an additional optimization to rb_erase_augmented, now
providing it as an inline function so that the augmented callbacks can be
inlined in. This provides an additional 5-10% performance improvement
for the interval tree insert/erase benchmark. There is a maintainance cost
as it exposes augmented rbtree users to some of the rbtree library internals;
however I think this cost shouldn't be too high as I expect the augmented
rbtree will always have much less users than the base rbtree.

I should probably add a quick summary of why I think it makes sense to
replace prio trees with augmented rbtree based interval trees now.  One of
the drivers is that we need augmented rbtrees for Rik's vma gap finding
code, and once you have them, it just makes sense to use them for interval
trees as well, as this is the simpler and more well known algorithm.  prio
trees, in comparison, seem *too* clever: they impose an additional 'heap'
constraint on the tree, which they use to guarantee a faster worst-case
complexity of O(k+log N) for stabbing queries in a well-balanced prio
tree, vs O(k*log N) for interval trees (where k=number of matches,
N=number of intervals).  Now this sounds great, but in practice prio trees
don't realize this theorical benefit.  First, the additional constraint
makes them harder to update, so that the kernel implementation has to
simplify things by balancing them like a radix tree, which is not always
ideal.  Second, the fact that there are both index and heap properties
makes both tree manipulation and search more complex, which results in a
higher multiplicative time constant.  As it turns out, the simple interval
tree algorithm ends up running faster than the more clever prio tree.

This patch:

Add two test modules:

- prio_tree_test measures the performance of lib/prio_tree.c, both for
  insertion/removal and for stabbing searches

- interval_tree_test measures the performance of a library of equivalent
  functionality, built using the augmented rbtree support.

In order to support the second test module, lib/interval_tree.c is
introduced. It is kept separate from the interval_tree_test main file
for two reasons: first we don't want to provide an unfair advantage
over prio_tree_test by having everything in a single compilation unit,
and second there is the possibility that the interval tree functionality
could get some non-test users in kernel over time.

Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: add RB_DECLARE_CALLBACKS() macro
Michel Lespinasse [Mon, 8 Oct 2012 23:31:21 +0000 (16:31 -0700)]
rbtree: add RB_DECLARE_CALLBACKS() macro

As proposed by Peter Zijlstra, this makes it easier to define the augmented
rbtree callbacks.

Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: remove prior augmented rbtree implementation
Michel Lespinasse [Mon, 8 Oct 2012 23:31:20 +0000 (16:31 -0700)]
rbtree: remove prior augmented rbtree implementation

convert arch/x86/mm/pat_rbtree.c to the proposed augmented rbtree api
and remove the old augmented rbtree implementation.

Signed-off-by: Michel Lespinasse <walken@google.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: faster augmented rbtree manipulation
Michel Lespinasse [Mon, 8 Oct 2012 23:31:17 +0000 (16:31 -0700)]
rbtree: faster augmented rbtree manipulation

Introduce new augmented rbtree APIs that allow minimal recalculation of
augmented node information.

A new callback is added to the rbtree insertion and erase rebalancing
functions, to be called on each tree rotations. Such rotations preserve
the subtree's root augmented value, but require recalculation of the one
child that was previously located at the subtree root.

In the insertion case, the handcoded search phase must be updated to
maintain the augmented information on insertion, and then the rbtree
coloring/rebalancing algorithms keep it up to date.

In the erase case, things are more complicated since it is library
code that manipulates the rbtree in order to remove internal nodes.
This requires a couple additional callbacks to copy a subtree's
augmented value when a new root is stitched in, and to recompute
augmented values down the ancestry path when a node is removed from
the tree.

In order to preserve maximum speed for the non-augmented case,
we provide two versions of each tree manipulation function.
rb_insert_augmented() is the augmented equivalent of rb_insert_color(),
and rb_erase_augmented() is the augmented equivalent of rb_erase().

Signed-off-by: Michel Lespinasse <walken@google.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: augmented rbtree test
Michel Lespinasse [Mon, 8 Oct 2012 23:31:15 +0000 (16:31 -0700)]
rbtree: augmented rbtree test

Small test to measure the performance of augmented rbtrees.

Signed-off-by: Michel Lespinasse <walken@google.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: low level optimizations in rb_erase()
Michel Lespinasse [Mon, 8 Oct 2012 23:31:13 +0000 (16:31 -0700)]
rbtree: low level optimizations in rb_erase()

Various minor optimizations in rb_erase():
- Avoid multiple loading of node->__rb_parent_color when computing parent
  and color information (possibly not in close sequence, as there might
  be further branches in the algorithm)
- In the 1-child subcase of case 1, copy the __rb_parent_color field from
  the erased node to the child instead of recomputing it from the desired
  parent and color
- When searching for the erased node's successor, differentiate between
  cases 2 and 3 based on whether any left links were followed. This avoids
  a condition later down.
- In case 3, keep a pointer to the erased node's right child so we don't
  have to refetch it later to adjust its parent.
- In the no-childs subcase of cases 2 and 3, place the rebalance assigment
  last so that the compiler can remove the following if(rebalance) test.

Also, added some comments to illustrate cases 2 and 3.

Signed-off-by: Michel Lespinasse <walken@google.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: handle 1-child recoloring in rb_erase() instead of rb_erase_color()
Michel Lespinasse [Mon, 8 Oct 2012 23:31:11 +0000 (16:31 -0700)]
rbtree: handle 1-child recoloring in rb_erase() instead of rb_erase_color()

An interesting observation for rb_erase() is that when a node has
exactly one child, the node must be black and the child must be red.
An interesting consequence is that removing such a node can be done by
simply replacing it with its child and making the child black,
which we can do efficiently in rb_erase(). __rb_erase_color() then
only needs to handle the no-childs case and can be modified accordingly.

Signed-off-by: Michel Lespinasse <walken@google.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: place easiest case first in rb_erase()
Michel Lespinasse [Mon, 8 Oct 2012 23:31:10 +0000 (16:31 -0700)]
rbtree: place easiest case first in rb_erase()

In rb_erase, move the easy case (node to erase has no more than
1 child) first. I feel the code reads easier that way.

Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: add __rb_change_child() helper function
Michel Lespinasse [Mon, 8 Oct 2012 23:31:07 +0000 (16:31 -0700)]
rbtree: add __rb_change_child() helper function

Add __rb_change_child() as an inline helper function to replace code that
would otherwise be duplicated 4 times in the source.

No changes to binary size or speed.

Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree test: fix sparse warning about 64-bit constant
Michel Lespinasse [Mon, 8 Oct 2012 23:31:04 +0000 (16:31 -0700)]
rbtree test: fix sparse warning about 64-bit constant

Just a small fix to make sparse happy.

Signed-off-by: Michel Lespinasse <walken@google.com>
Reported-by: Fengguang Wu <wfg@linux.intel.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: optimize fetching of sibling node
Michel Lespinasse [Mon, 8 Oct 2012 23:31:02 +0000 (16:31 -0700)]
rbtree: optimize fetching of sibling node

When looking to fetch a node's sibling, we went through a sequence of:
- check if node is the parent's left child
- if it is, then fetch the parent's right child

This can be replaced with:
- fetch the parent's right child as an assumed sibling
- check that node is NOT the fetched child

This avoids fetching the parent's left child when node is actually
that child. Saves a bit on code size, though it doesn't seem to make
a large difference in speed.

Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <David.Woodhouse@intel.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Daniel Santos <daniel.santos@pobox.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: coding style adjustments
Michel Lespinasse [Mon, 8 Oct 2012 23:31:01 +0000 (16:31 -0700)]
rbtree: coding style adjustments

Set comment and indentation style to be consistent with linux coding style
and the rest of the file, as suggested by Peter Zijlstra

Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Daniel Santos <daniel.santos@pobox.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: low level optimizations in __rb_erase_color()
Michel Lespinasse [Mon, 8 Oct 2012 23:30:57 +0000 (16:30 -0700)]
rbtree: low level optimizations in __rb_erase_color()

In __rb_erase_color(), we often already have pointers to the nodes being
rotated and/or know what their colors must be, so we can generate more
efficient code than the generic __rb_rotate_left() and __rb_rotate_right()
functions.

Also when the current node is red or when flipping the sibling's color,
the parent is already known so we can use the more efficient
rb_set_parent_color() function to set the desired color.

Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Daniel Santos <daniel.santos@pobox.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: optimize case selection logic in __rb_erase_color()
Michel Lespinasse [Mon, 8 Oct 2012 23:30:54 +0000 (16:30 -0700)]
rbtree: optimize case selection logic in __rb_erase_color()

In __rb_erase_color(), we have to select one of 3 cases depending on the
color on the 'other' node children.  If both children are black, we flip a
few node colors and iterate.  Otherwise, we do either one or two tree
rotations, depending on the color of the 'other' child opposite to 'node',
and then we are done.

The corresponding logic had duplicate checks for the color of the 'other'
child opposite to 'node'.  It was checking it first to determine if both
children are black, and then to determine how many tree rotations are
required.  Rearrange the logic to avoid that extra check.

Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Daniel Santos <daniel.santos@pobox.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: adjust node color in __rb_erase_color() only when necessary
Michel Lespinasse [Mon, 8 Oct 2012 23:30:50 +0000 (16:30 -0700)]
rbtree: adjust node color in __rb_erase_color() only when necessary

In __rb_erase_color(), we were always setting a node to black after
exiting the main loop.  And in one case, after fixing up the tree to
satisfy all rbtree invariants, we were setting the current node to root
just to guarantee a loop exit, at which point the root would be set to
black.  However this is not necessary, as the root of an rbtree is already
known to be black.  The only case where the color flip is required is when
we exit the loop due to the current node being red, and it's easiest to
just do the flip at that point instead of doing it after the loop.

[adrian.hunter@intel.com: perf tools: fix build for another rbtree.c change]
Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Daniel Santos <daniel.santos@pobox.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: low level optimizations in rb_insert_color()
Michel Lespinasse [Mon, 8 Oct 2012 23:30:47 +0000 (16:30 -0700)]
rbtree: low level optimizations in rb_insert_color()

- Use the newly introduced rb_set_parent_color() function to flip the color
  of nodes whose parent is already known.
- Optimize rb_parent() when the node is known to be red - there is no need
  to mask out the color in that case.
- Flipping gparent's color to red requires us to fetch its rb_parent_color
  field, so we can reuse it as the parent value for the next loop iteration.
- Do not use __rb_rotate_left() and __rb_rotate_right() to handle tree
  rotations: we already have pointers to all relevant nodes, and know their
  colors (either because we want to adjust it, or because we've tested it,
  or we can deduce it as black due to the node proximity to a known red node).
  So we can generate more efficient code by making use of the node pointers
  we already have, and setting both the parent and color attributes for
  nodes all at once. Also in Case 2, some node attributes don't have to
  be set because we know another tree rotation (Case 3) will always follow
  and override them.

Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Daniel Santos <daniel.santos@pobox.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: adjust root color in rb_insert_color() only when necessary
Michel Lespinasse [Mon, 8 Oct 2012 23:30:44 +0000 (16:30 -0700)]
rbtree: adjust root color in rb_insert_color() only when necessary

The root node of an rbtree must always be black.  However,
rb_insert_color() only needs to maintain this invariant when it has been
broken - that is, when it exits the loop due to the current (red) node
being the root.  In all other cases (exiting after tree rotations, or
exiting due to an existing black parent) the invariant is already
satisfied, so there is no need to adjust the root node color.

Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Daniel Santos <daniel.santos@pobox.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: break out of rb_insert_color loop after tree rotation
Michel Lespinasse [Mon, 8 Oct 2012 23:30:42 +0000 (16:30 -0700)]
rbtree: break out of rb_insert_color loop after tree rotation

It is a well known property of rbtrees that insertion never requires more
than two tree rotations.  In our implementation, after one loop iteration
identified one or two necessary tree rotations, we would iterate and look
for more.  However at that point the node's parent would always be black,
which would cause us to exit the loop.

We can make the code flow more obvious by just adding a break statement
after the tree rotations, where we know we are done.  Additionally, in the
cases where two tree rotations are necessary, we don't have to update the
'node' pointer as it wouldn't be used until the next loop iteration, which
we now avoid due to this break statement.

Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Daniel Santos <daniel.santos@pobox.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: performance and correctness test
Michel Lespinasse [Mon, 8 Oct 2012 23:30:39 +0000 (16:30 -0700)]
rbtree: performance and correctness test

This small module helps measure the performance of rbtree insert and
erase.

Additionally, we run a few correctness tests to check that the rbtrees
have all desired properties:

- contains the right number of nodes in the order desired,
- never two consecutive red nodes on any path,
- all paths to leaf nodes have the same number of black nodes,
- root node is black

[akpm@linux-foundation.org: fix printk warning: sparc64 cycles_t is unsigned long]
Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Daniel Santos <daniel.santos@pobox.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: move some implementation details from rbtree.h to rbtree.c
Michel Lespinasse [Mon, 8 Oct 2012 23:30:37 +0000 (16:30 -0700)]
rbtree: move some implementation details from rbtree.h to rbtree.c

rbtree users must use the documented APIs to manipulate the tree
structure.  Low-level helpers to manipulate node colors and parenthood are
not part of that API, so move them to lib/rbtree.c

[dwmw2@infradead.org: fix jffs2 build issue due to renamed __rb_parent_color field]
Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Daniel Santos <daniel.santos@pobox.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: fix incorrect rbtree node insertion in fs/proc/proc_sysctl.c
Michel Lespinasse [Mon, 8 Oct 2012 23:30:35 +0000 (16:30 -0700)]
rbtree: fix incorrect rbtree node insertion in fs/proc/proc_sysctl.c

The recently added code to use rbtrees in sysctl did not follow the proper
rbtree interface on insertion - it was calling rb_link_node() which
inserts a new node into the binary tree, but missed the call to
rb_insert_color() which properly balances the rbtree and establishes all
expected rbtree invariants.

I found out about this only because faulty commit also used
rb_init_node(), which I am removing within this patchset.  But I think
it's an easy mistake to make, and it makes me wonder if we should change
the rbtree API so that insertions would be done with a single rb_insert()
call (even if its implementation could still inline the rb_link_node()
part and call a private __rb_insert_color function to do the rebalancing).

Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Daniel Santos <daniel.santos@pobox.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: empty nodes have no color
Michel Lespinasse [Mon, 8 Oct 2012 23:30:32 +0000 (16:30 -0700)]
rbtree: empty nodes have no color

Empty nodes have no color.  We can make use of this property to simplify
the code emitted by the RB_EMPTY_NODE and RB_CLEAR_NODE macros.  Also,
we can get rid of the rb_init_node function which had been introduced by
commit 88d19cf37952 ("timers: Add rb_init_node() to allow for stack
allocated rb nodes") to avoid some issue with the empty node's color not
being initialized.

I'm not sure what the RB_EMPTY_NODE checks in rb_prev() / rb_next() are
doing there, though.  axboe introduced them in commit 10fd48f2376d
("rbtree: fixed reversed RB_EMPTY_NODE and rb_next/prev").  The way I
see it, the 'empty node' abstraction is only used by rbtree users to
flag nodes that they haven't inserted in any rbtree, so asking the
predecessor or successor of such nodes doesn't make any sense.

One final rb_init_node() caller was recently added in sysctl code to
implement faster sysctl name lookups.  This code doesn't make use of
RB_EMPTY_NODE at all, and from what I could see it only called
rb_init_node() under the mistaken assumption that such initialization was
required before node insertion.

[sfr@canb.auug.org.au: fix net/ceph/osd_client.c build]
Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Daniel Santos <daniel.santos@pobox.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: John Stultz <john.stultz@linaro.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorbtree: reference Documentation/rbtree.txt for usage instructions
Michel Lespinasse [Mon, 8 Oct 2012 23:30:28 +0000 (16:30 -0700)]
rbtree: reference Documentation/rbtree.txt for usage instructions

I recently started looking at the rbtree code (with an eye towards
improving the augmented rbtree support, but I haven't gotten there yet).
I noticed a lot of possible speed improvements, which I am now proposing
in this patch set.

Patches 1-4 are preparatory: remove internal functions from rbtree.h so
that users won't be tempted to use them instead of the documented APIs,
clean up some incorrect usages I've noticed (in particular, with the
recently added fs/proc/proc_sysctl.c rbtree usage), reference the
documentation so that people have one less excuse to miss it, etc.

Patch 5 is a small module I wrote to check the rbtree performance.  It
creates 100 nodes with random keys and repeatedly inserts and erases them
from an rbtree.  Additionally, it has code to check for rbtree invariants
after each insert or erase operation.

Patches 6-12 is where the rbtree optimizations are done, and they touch
only that one file, lib/rbtree.c .  I am getting good results out of these
- in my small benchmark doing rbtree insertion (including search) and
erase, I'm seeing a 30% runtime reduction on Sandybridge E5, which is more
than I initially thought would be possible.  (the results aren't as
impressive on my two other test hosts though, AMD barcelona and Intel
Westmere, where I am seeing 14% runtime reduction only).  The code size -
both source (ommiting comments) and compiled - is also shorter after these
changes.  However, I do admit that the updated code is more arduous to
read - one big reason for that is the removal of the tree rotation
helpers, which added some overhead but also made it easier to reason about
things locally.  Overall, I believe this is an acceptable compromise,
given that this code doesn't get modified very often, and that I have good
tests for it.

Upon Peter's suggestion, I added comments showing the rtree configuration
before every rotation.  I think they help; however it's still best to have
a copy of the cormen/leiserson/rivest book when digging into this code.

This patch: reference Documentation/rbtree.txt for usage instructions

include/linux/rbtree.h included some basic usage instructions, while
Documentation/rbtree.txt had some more complete and easier to follow
instructions.  Replacing the former with a reference to the latter.

Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Daniel Santos <daniel.santos@pobox.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agoipc/mqueue: remove unnecessary rb_init_node() calls
Michel Lespinasse [Mon, 8 Oct 2012 23:30:26 +0000 (16:30 -0700)]
ipc/mqueue: remove unnecessary rb_init_node() calls

Commit d6629859b36d ("ipc/mqueue: improve performance of send/recv") and
ce2d52cc ("ipc/mqueue: add rbtree node caching support") introduced an
rbtree of message priorities, and usage of rb_init_node() to initialize
the corresponding nodes.  As it turns out, rb_init_node() is unnecessary
here, as the nodes are fully initialized on insertion by rb_link_node()
and the code doesn't access nodes that aren't inserted on the rbtree.

Removing the rb_init_node() calls as I removed that function during
rbtree API cleanups (the only other use of it was in a place that
similarly didn't require it).

Signed-off-by: Michel Lespinasse <walken@google.com>
Acked-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp, s390: architecture backend for thp on s390
Gerald Schaefer [Mon, 8 Oct 2012 23:30:24 +0000 (16:30 -0700)]
thp, s390: architecture backend for thp on s390

This implements the architecture backend for transparent hugepages
on s390.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp, s390: disable thp for kvm host on s390
Gerald Schaefer [Mon, 8 Oct 2012 23:30:21 +0000 (16:30 -0700)]
thp, s390: disable thp for kvm host on s390

This patch is part of the architecture backend for thp on s390.  It
disables thp for kvm hosts, because there is no kvm host hugepage support
so far.  Existing thp mappings are split by follow_page() with FOLL_SPLIT,
and future thp mappings are prevented by setting VM_NOHUGEPAGE in
mm->def_flags.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp, s390: thp pagetable pre-allocation for s390
Gerald Schaefer [Mon, 8 Oct 2012 23:30:18 +0000 (16:30 -0700)]
thp, s390: thp pagetable pre-allocation for s390

This patch is part of the architecture backend for thp on s390.  It
provides the pagetable pre-allocation functions
pgtable_trans_huge_deposit() and pgtable_trans_huge_withdraw().  Unlike
other archs, s390 has no struct page * as pgtable_t, but rather a pointer
to the page table.  So instead of saving the pagetable pre- allocation
list info inside the struct page, it is being saved within the pagetable
itself.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp, s390: thp splitting backend for s390
Gerald Schaefer [Mon, 8 Oct 2012 23:30:15 +0000 (16:30 -0700)]
thp, s390: thp splitting backend for s390

This patch is part of the architecture backend for thp on s390.  It
provides the functions related to thp splitting, including serialization
against gup.  Unlike other archs, pmdp_splitting_flush() cannot use a tlb
flushing operation to serialize against gup on s390, because that wouldn't
be stopped by the disabled IRQs.  So instead, smp_call_function() is
called with an empty function, which will have the expected effect.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp: make MADV_HUGEPAGE check for mm->def_flags
Gerald Schaefer [Mon, 8 Oct 2012 23:30:12 +0000 (16:30 -0700)]
thp: make MADV_HUGEPAGE check for mm->def_flags

This adds a check to hugepage_madvise(), to refuse MADV_HUGEPAGE if
VM_NOHUGEPAGE is set in mm->def_flags.  On s390, the VM_NOHUGEPAGE flag
will be set in mm->def_flags for kvm processes, to prevent any future thp
mappings.  In order to also prevent MADV_HUGEPAGE on such an mm,
hugepage_madvise() should check mm->def_flags.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp: introduce pmdp_invalidate()
Gerald Schaefer [Mon, 8 Oct 2012 23:30:09 +0000 (16:30 -0700)]
thp: introduce pmdp_invalidate()

On s390, a valid page table entry must not be changed while it is attached
to any CPU.  So instead of pmd_mknotpresent() and set_pmd_at(), an IDTE
operation would be necessary there.  This patch introduces the
pmdp_invalidate() function, to allow architecture-specific
implementations.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp: remove assumptions on pgtable_t type
Gerald Schaefer [Mon, 8 Oct 2012 23:30:07 +0000 (16:30 -0700)]
thp: remove assumptions on pgtable_t type

The thp page table pre-allocation code currently assumes that pgtable_t is
of type "struct page *".  This may not be true for all architectures, so
this patch removes that assumption by replacing the functions
prepare_pmd_huge_pte() and get_pmd_huge_pte() with two new functions that
can be defined architecture-specific.

It also removes two VM_BUG_ON checks for page_count() and page_mapcount()
operating on a pgtable_t.  Apart from the VM_BUG_ON removal, there will be
no functional change introduced by this patch.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp, x86: introduce HAVE_ARCH_TRANSPARENT_HUGEPAGE
Gerald Schaefer [Mon, 8 Oct 2012 23:30:04 +0000 (16:30 -0700)]
thp, x86: introduce HAVE_ARCH_TRANSPARENT_HUGEPAGE

Cleanup patch in preparation for transparent hugepage support on s390.
Adding new architectures to the TRANSPARENT_HUGEPAGE config option can
make the "depends" line rather ugly, like "depends on (X86 || (S390 &&
64BIT)) && MMU".

This patch adds a HAVE_ARCH_TRANSPARENT_HUGEPAGE instead.  x86 already has
MMU "def_bool y", so the MMU check is superfluous there and
HAVE_ARCH_TRANSPARENT_HUGEPAGE can be selected in arch/x86/Kconfig.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: fix potential anon_vma locking issue in mprotect()
Michel Lespinasse [Mon, 8 Oct 2012 23:30:01 +0000 (16:30 -0700)]
mm: fix potential anon_vma locking issue in mprotect()

Fix an anon_vma locking issue in the following situation:

- vma has no anon_vma
- next has an anon_vma
- vma is being shrunk / next is being expanded, due to an mprotect call

We need to take next's anon_vma lock to avoid races with rmap users (such
as page migration) while next is being expanded.

Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp: remove unnecessary set_recommended_min_free_kbytes
Xiao Guangrong [Mon, 8 Oct 2012 23:29:59 +0000 (16:29 -0700)]
thp: remove unnecessary set_recommended_min_free_kbytes

Since it is called in start_khugepaged

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp: use khugepaged_enabled to remove duplicate code
Xiao Guangrong [Mon, 8 Oct 2012 23:29:56 +0000 (16:29 -0700)]
thp: use khugepaged_enabled to remove duplicate code

Use khugepaged_enabled to see whether thp is enabled

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp: remove khugepaged_loop
Xiao Guangrong [Mon, 8 Oct 2012 23:29:54 +0000 (16:29 -0700)]
thp: remove khugepaged_loop

Merge khugepaged_loop into khugepaged

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp: introduce khugepaged_prealloc_page and khugepaged_alloc_page
Xiao Guangrong [Mon, 8 Oct 2012 23:29:51 +0000 (16:29 -0700)]
thp: introduce khugepaged_prealloc_page and khugepaged_alloc_page

They are used to abstract the difference between NUMA enabled and NUMA
disabled to make the code more readable

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp: release page in page pre-alloc path
Xiao Guangrong [Mon, 8 Oct 2012 23:29:49 +0000 (16:29 -0700)]
thp: release page in page pre-alloc path

If NUMA is enabled, we can release the page in the page pre-alloc
operation, then the CONFIG_NUMA dependent code can be reduced

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp: merge page pre-alloc in khugepaged_loop into khugepaged_do_scan
Xiao Guangrong [Mon, 8 Oct 2012 23:29:48 +0000 (16:29 -0700)]
thp: merge page pre-alloc in khugepaged_loop into khugepaged_do_scan

There are two pre-alloc operations in these two function, the different is:
- it allows to sleep if page alloc fail in khugepaged_loop
- it exits immediately if page alloc fail in khugepaged_do_scan

Actually, in khugepaged_do_scan, we can allow the pre-alloc to sleep on
the first failure, then the operation in khugepaged_loop can be removed

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp: remove some code depend on CONFIG_NUMA
Xiao Guangrong [Mon, 8 Oct 2012 23:29:46 +0000 (16:29 -0700)]
thp: remove some code depend on CONFIG_NUMA

If NUMA is disabled, hpage is used as page pre-alloc, so there are two
cases for hpage:

- it is !NULL, means the page is not consumed otherwise,
- the page has been consumed

If NUMA is enabled, hpage is just used as alloc-fail indicator which is
not a real page, NULL means not fail triggered.

So, we can release the page only if !IS_ERR_OR_NULL

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp: remove wake_up_interruptible in the exit path
Xiao Guangrong [Mon, 8 Oct 2012 23:29:44 +0000 (16:29 -0700)]
thp: remove wake_up_interruptible in the exit path

Add the check of kthread_should_stop() to the conditions which are used to
wakeup on khugepaged_wait, then kthread_stop is enough to let the thread
exit

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp: remove unnecessary khugepaged_thread check
Xiao Guangrong [Mon, 8 Oct 2012 23:29:42 +0000 (16:29 -0700)]
thp: remove unnecessary khugepaged_thread check

Now, khugepaged creation and cancel are completely serial under the
protection of khugepaged_mutex, it is impossible that many khugepaged
entities are running

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp: move khugepaged_mutex out of khugepaged
Xiao Guangrong [Mon, 8 Oct 2012 23:29:41 +0000 (16:29 -0700)]
thp: move khugepaged_mutex out of khugepaged

Currently, hugepaged_mutex is used really complexly and hard to
understand, actually, it is just used to serialize start_khugepaged and
khugepaged for these reasons:

- khugepaged_thread is shared between them
- the thp disable path (echo never > transparent_hugepage/enabled) is
  nonblocking, so we need to protect khugepaged_thread to get a stable
  running state

These can be avoided by:

- use the lock to serialize the thread creation and cancel
- thp disable path can not finised until the thread exits

Then khugepaged_thread is fully controlled by start_khugepaged, khugepaged
will be happy without the lock

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp: remove unnecessary check in start_khugepaged
Xiao Guangrong [Mon, 8 Oct 2012 23:29:38 +0000 (16:29 -0700)]
thp: remove unnecessary check in start_khugepaged

The check is unnecessary since if mm_slot_cache or mm_slots_hash
initialize failed, no sysfs interface will be created

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agothp: fix the count of THP_COLLAPSE_ALLOC
Xiao Guangrong [Mon, 8 Oct 2012 23:29:35 +0000 (16:29 -0700)]
thp: fix the count of THP_COLLAPSE_ALLOC

THP_COLLAPSE_ALLOC is double counted if NUMA is disabled since it has
already been calculated in khugepaged_alloc_hugepage

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: adjust final #endif position in mm/internal.h
Michel Lespinasse [Mon, 8 Oct 2012 23:29:34 +0000 (16:29 -0700)]
mm: adjust final #endif position in mm/internal.h

Make sure the #endif that terminates the standard #ifndef / #define /
#endif construct gets labeled, and gets positioned at the end of the file
as is normally the case.

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: hugetlb: add arch hook for clearing page flags before entering pool
Will Deacon [Mon, 8 Oct 2012 23:29:32 +0000 (16:29 -0700)]
mm: hugetlb: add arch hook for clearing page flags before entering pool

The core page allocator ensures that page flags are zeroed when freeing
pages via free_pages_check.  A number of architectures (ARM, PPC, MIPS)
rely on this property to treat new pages as dirty with respect to the data
cache and perform the appropriate flushing before mapping the pages into
userspace.

This can lead to cache synchronisation problems when using hugepages,
since the allocator keeps its own pool of pages above the usual page
allocator and does not reset the page flags when freeing a page into the
pool.

This patch adds a new architecture hook, arch_clear_hugepage_flags, so
that architectures which rely on the page flags being in a particular
state for fresh allocations can adjust the flags accordingly when a page
is freed into the pool.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Cc: Michal Hocko <mhocko@suse.cz>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agooom: remove deprecated oom_adj
Davidlohr Bueso [Mon, 8 Oct 2012 23:29:30 +0000 (16:29 -0700)]
oom: remove deprecated oom_adj

The deprecated /proc/<pid>/oom_adj is scheduled for removal this month.

Signed-off-by: Davidlohr Bueso <dave@gnu.org>
Acked-by: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm/vmscan: fix error number for failed kthread
Gavin Shan [Mon, 8 Oct 2012 23:29:27 +0000 (16:29 -0700)]
mm/vmscan: fix error number for failed kthread

Fix the return value while failing to create the kswapd kernel thread.
Also, the error message is prioritized as KERN_ERR.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm/mmu_notifier: init notifier if necessary
Gavin Shan [Mon, 8 Oct 2012 23:29:26 +0000 (16:29 -0700)]
mm/mmu_notifier: init notifier if necessary

While registering MMU notifier, new instance of MMU notifier_mm will be
allocated and later free'd if currrent mm_struct's MMU notifier_mm has
been initialized.  That causes some overhead.  The patch tries to
elominate that.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Sagi Grimberg <sagig@mellanox.co.il>
Cc: Haggai Eran <haggaie@mellanox.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: mmu_notifier: have mmu_notifiers use a global SRCU so they may safely schedule
Sagi Grimberg [Mon, 8 Oct 2012 23:29:24 +0000 (16:29 -0700)]
mm: mmu_notifier: have mmu_notifiers use a global SRCU so they may safely schedule

With an RCU based mmu_notifier implementation, any callout to
mmu_notifier_invalidate_range_{start,end}() or
mmu_notifier_invalidate_page() would not be allowed to call schedule()
as that could potentially allow a modification to the mmu_notifier
structure while it is currently being used.

Since srcu allocs 4 machine words per instance per cpu, we may end up
with memory exhaustion if we use srcu per mm.  So all mms share a global
srcu.  Note that during large mmu_notifier activity exit & unregister
paths might hang for longer periods, but it is tolerable for current
mmu_notifier clients.

Signed-off-by: Sagi Grimberg <sagig@mellanox.co.il>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Haggai Eran <haggaie@mellanox.com>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: mmu_notifier: fix inconsistent memory between secondary MMU and host
Xiao Guangrong [Mon, 8 Oct 2012 23:29:23 +0000 (16:29 -0700)]
mm: mmu_notifier: fix inconsistent memory between secondary MMU and host

There is a bug in set_pte_at_notify() which always sets the pte to the
new page before releasing the old page in the secondary MMU.  At this
time, the process will access on the new page, but the secondary MMU
still access on the old page, the memory is inconsistent between them

The below scenario shows the bug more clearly:

at the beginning: *p = 0, and p is write-protected by KSM or shared with
parent process

CPU 0                                       CPU 1
write 1 to p to trigger COW,
set_pte_at_notify will be called:
  *pte = new_page + W; /* The W bit of pte is set */

                                     *p = 1; /* pte is valid, so no #PF */

                                     return back to secondary MMU, then
                                     the secondary MMU read p, but get:
                                     *p == 0;

                         /*
                          * !!!!!!
                          * the host has already set p to 1, but the secondary
                          * MMU still get the old value 0
                          */

  call mmu_notifier_change_pte to release
  old page in secondary MMU

We can fix it by release old page first, then set the pte to the new
page.

Note, the new page will be firstly used in secondary MMU before it is
mapped into the page table of the process, but this is safe because it
is protected by the page table lock, there is no race to change the pte

[akpm@linux-foundation.org: add comment from Andrea]
Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomempolicy: fix a memory corruption by refcount imbalance in alloc_pages_vma()
Mel Gorman [Mon, 8 Oct 2012 23:29:20 +0000 (16:29 -0700)]
mempolicy: fix a memory corruption by refcount imbalance in alloc_pages_vma()

Commit cc9a6c877661 ("cpuset: mm: reduce large amounts of memory barrier
related damage v3") introduced a potential memory corruption.
shmem_alloc_page() uses a pseudo vma and it has one significant unique
combination, vma->vm_ops=NULL and vma->policy->flags & MPOL_F_SHARED.

get_vma_policy() does NOT increase a policy ref when vma->vm_ops=NULL
and mpol_cond_put() DOES decrease a policy ref when a policy has
MPOL_F_SHARED.  Therefore, when a cpuset update race occurs,
alloc_pages_vma() falls in 'goto retry_cpuset' path, decrements the
reference count and frees the policy prematurely.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Christoph Lameter <cl@linux.com>
Cc: Josh Boyer <jwboyer@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomempolicy: fix refcount leak in mpol_set_shared_policy()
KOSAKI Motohiro [Mon, 8 Oct 2012 23:29:19 +0000 (16:29 -0700)]
mempolicy: fix refcount leak in mpol_set_shared_policy()

When shared_policy_replace() fails to allocate new->policy is not freed
correctly by mpol_set_shared_policy().  The problem is that shared
mempolicy code directly call kmem_cache_free() in multiple places where
it is easy to make a mistake.

This patch creates an sp_free wrapper function and uses it. The bug was
introduced pre-git age (IOW, before 2.6.12-rc2).

[mgorman@suse.de: Editted changelog]
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Christoph Lameter <cl@linux.com>
Cc: Josh Boyer <jwboyer@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomempolicy: fix a race in shared_policy_replace()
Mel Gorman [Mon, 8 Oct 2012 23:29:17 +0000 (16:29 -0700)]
mempolicy: fix a race in shared_policy_replace()

shared_policy_replace() use of sp_alloc() is unsafe.  1) sp_node cannot
be dereferenced if sp->lock is not held and 2) another thread can modify
sp_node between spin_unlock for allocating a new sp node and next
spin_lock.  The bug was introduced before 2.6.12-rc2.

Kosaki's original patch for this problem was to allocate an sp node and
policy within shared_policy_replace and initialise it when the lock is
reacquired.  I was not keen on this approach because it partially
duplicates sp_alloc().  As the paths were sp->lock is taken are not that
performance critical this patch converts sp->lock to sp->mutex so it can
sleep when calling sp_alloc().

[kosaki.motohiro@jp.fujitsu.com: Original patch]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Christoph Lameter <cl@linux.com>
Cc: Josh Boyer <jwboyer@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomempolicy: remove mempolicy sharing
KOSAKI Motohiro [Mon, 8 Oct 2012 23:29:16 +0000 (16:29 -0700)]
mempolicy: remove mempolicy sharing

Dave Jones' system call fuzz testing tool "trinity" triggered the
following bug error with slab debugging enabled

    =============================================================================
    BUG numa_policy (Not tainted): Poison overwritten
    -----------------------------------------------------------------------------

    INFO: 0xffff880146498250-0xffff880146498250. First byte 0x6a instead of 0x6b
    INFO: Allocated in mpol_new+0xa3/0x140 age=46310 cpu=6 pid=32154
     __slab_alloc+0x3d3/0x445
     kmem_cache_alloc+0x29d/0x2b0
     mpol_new+0xa3/0x140
     sys_mbind+0x142/0x620
     system_call_fastpath+0x16/0x1b

    INFO: Freed in __mpol_put+0x27/0x30 age=46268 cpu=6 pid=32154
     __slab_free+0x2e/0x1de
     kmem_cache_free+0x25a/0x260
     __mpol_put+0x27/0x30
     remove_vma+0x68/0x90
     exit_mmap+0x118/0x140
     mmput+0x73/0x110
     exit_mm+0x108/0x130
     do_exit+0x162/0xb90
     do_group_exit+0x4f/0xc0
     sys_exit_group+0x17/0x20
     system_call_fastpath+0x16/0x1b

    INFO: Slab 0xffffea0005192600 objects=27 used=27 fp=0x          (null) flags=0x20000000004080
    INFO: Object 0xffff880146498250 @offset=592 fp=0xffff88014649b9d0

The problem is that the structure is being prematurely freed due to a
reference count imbalance. In the following case mbind(addr, len) should
replace the memory policies of both vma1 and vma2 and thus they will
become to share the same mempolicy and the new mempolicy will have the
MPOL_F_SHARED flag.

  +-------------------+-------------------+
  |     vma1          |     vma2(shmem)   |
  +-------------------+-------------------+
  |                                       |
 addr                                 addr+len

alloc_pages_vma() uses get_vma_policy() and mpol_cond_put() pair for
maintaining the mempolicy reference count.  The current rule is that
get_vma_policy() only increments refcount for shmem VMA and
mpol_conf_put() only decrements refcount if the policy has
MPOL_F_SHARED.

In above case, vma1 is not shmem vma and vma->policy has MPOL_F_SHARED!
The reference count will be decreased even though was not increased
whenever alloc_page_vma() is called.  This has been broken since commit
[52cd3b07: mempolicy: rework mempolicy Reference Counting] in 2008.

There is another serious bug with the sharing of memory policies.
Currently, mempolicy rebind logic (it is called from cpuset rebinding)
ignores a refcount of mempolicy and override it forcibly.  Thus, any
mempolicy sharing may cause mempolicy corruption.  The bug was
introduced by commit [68860ec1: cpusets: automatic numa mempolicy
rebinding].

Ideally, the shared policy handling would be rewritten to either
properly handle COW of the policy structures or at least reference count
MPOL_F_SHARED based exclusively on information within the policy.
However, this patch takes the easier approach of disabling any policy
sharing between VMAs.  Each new range allocated with sp_alloc will
allocate a new policy, set the reference count to 1 and drop the
reference count of the old policy.  This increases the memory footprint
but is not expected to be a major problem as mbind() is unlikely to be
used for fine-grained ranges.  It is also inefficient because it means
we allocate a new policy even in cases where mbind_range() could use the
new_policy passed to it.  However, it is more straight-forward and the
change should be invisible to the user.

[mgorman@suse.de: Edited changelog]
Reported-by: Dave Jones <davej@redhat.com>,
Cc: Christoph Lameter <cl@linux.com>,
Reviewed-by: Christoph Lameter <cl@linux.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Josh Boyer <jwboyer@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agorevert "mm: mempolicy: Let vma_merge and vma_split handle vma->vm_policy linkages"
KOSAKI Motohiro [Mon, 8 Oct 2012 23:29:14 +0000 (16:29 -0700)]
revert "mm: mempolicy: Let vma_merge and vma_split handle vma->vm_policy linkages"

Commit 05f144a0d5c2 ("mm: mempolicy: Let vma_merge and vma_split handle
vma->vm_policy linkages") removed vma->vm_policy updates code but it is
the purpose of mbind_range().  Now, mbind_range() is virtually a no-op
and while it does not allow memory corruption it is not the right fix.
This patch is a revert.

[mgorman@suse.de: Edited changelog]
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: Josh Boyer <jwboyer@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: compaction: capture a suitable high-order page immediately when it is made available
Mel Gorman [Mon, 8 Oct 2012 23:29:12 +0000 (16:29 -0700)]
mm: compaction: capture a suitable high-order page immediately when it is made available

While compaction is migrating pages to free up large contiguous blocks
for allocation it races with other allocation requests that may steal
these blocks or break them up.  This patch alters direct compaction to
capture a suitable free page as soon as it becomes available to reduce
this race.  It uses similar logic to split_free_page() to ensure that
watermarks are still obeyed.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: vmscan: scale number of pages reclaimed by reclaim/compaction based on failures
Mel Gorman [Mon, 8 Oct 2012 23:29:11 +0000 (16:29 -0700)]
mm: vmscan: scale number of pages reclaimed by reclaim/compaction based on failures

If allocation fails after compaction then compaction may be deferred for
a number of allocation attempts.  If there are subsequent failures,
compact_defer_shift is increased to defer for longer periods.  This
patch uses that information to scale the number of pages reclaimed with
compact_defer_shift until allocations succeed again.  The rationale is
that reclaiming the normal number of pages still allowed compaction to
fail and its success depends on the number of pages.  If it's failing,
reclaim more pages until it succeeds again.

Note that this is not implying that VM reclaim is not reclaiming enough
pages or that its logic is broken.  try_to_free_pages() always asks for
SWAP_CLUSTER_MAX pages to be reclaimed regardless of order and that is
what it does.  Direct reclaim stops normally with this check.

if (sc->nr_reclaimed >= sc->nr_to_reclaim)
goto out;

should_continue_reclaim delays when that check is made until a minimum
number of pages for reclaim/compaction are reclaimed.  It is possible
that this patch could instead set nr_to_reclaim in try_to_free_pages()
and drive it from there but that's behaves differently and not
necessarily for the better.  If driven from do_try_to_free_pages(), it
is also possible that priorities will rise.

When they reach DEF_PRIORITY-2, it will also start stalling and setting
pages for immediate reclaim which is more disruptive than not desirable
in this case.  That is a more wide-reaching change that could cause
another regression related to THP requests causing interactive jitter.

[akpm@linux-foundation.org: fix build]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: compaction: update comment in try_to_compact_pages
Mel Gorman [Mon, 8 Oct 2012 23:29:09 +0000 (16:29 -0700)]
mm: compaction: update comment in try_to_compact_pages

Allocation success rates have been far lower since 3.4 due to commit
fe2c2a106663 ("vmscan: reclaim at order 0 when compaction is enabled").
This commit was introduced for good reasons and it was known in advance
that the success rates would suffer but it was justified on the grounds
that the high allocation success rates were achieved by aggressive
reclaim.  Success rates are expected to suffer even more in 3.6 due to
commit 7db8889ab05b ("mm: have order > 0 compaction start off where it
left") which testing has shown to severely reduce allocation success
rates under load - to 0% in one case.

This series aims to improve the allocation success rates without
regressing the benefits of commit fe2c2a106663.  The series is based on
latest mmotm and takes into account the __GFP_NO_KSWAPD flag is going
away.

Patch 1 updates a stale comment seeing as I was in the general area.

Patch 2 updates reclaim/compaction to reclaim pages scaled on the number
of recent failures.

Patch 3 captures suitable high-order pages freed by compaction to reduce
races with parallel allocation requests.

Patch 4 fixes the upstream commit [7db8889a: mm: have order > 0 compaction
start off where it left] to enable compaction again

Patch 5 identifies when compacion is taking too long due to contention
and aborts.

STRESS-HIGHALLOC
 3.6-rc1-akpm   full-series
Pass 1          36.00 ( 0.00%)    51.00 (15.00%)
Pass 2          42.00 ( 0.00%)    63.00 (21.00%)
while Rested    86.00 ( 0.00%)    86.00 ( 0.00%)

From

  http://www.csn.ul.ie/~mel/postings/mmtests-20120424/global-dhp__stress-highalloc-performance-ext3/hydra/comparison.html

I know that the allocation success rates in 3.3.6 was 78% in comparison
to 36% in in the current akpm tree.  With the full series applied, the
success rates are up to around 51% with some variability in the results.
This is not as high a success rate but it does not reclaim excessively
which is a key point.

MMTests Statistics: vmstat
Page Ins                                     3050912     3078892
Page Outs                                    8033528     8039096
Swap Ins                                           0           0
Swap Outs                                          0           0

Note that swap in/out rates remain at 0. In 3.3.6 with 78% success rates
there were 71881 pages swapped out.

Direct pages scanned                           70942      122976
Kswapd pages scanned                         1366300     1520122
Kswapd pages reclaimed                       1366214     1484629
Direct pages reclaimed                         70936      105716
Kswapd efficiency                                99%         97%
Kswapd velocity                             1072.550    1182.615
Direct efficiency                                99%         85%
Direct velocity                               55.690      95.672

The kswapd velocity changes very little as expected.  kswapd velocity is
around the 1000 pages/sec mark where as in kernel 3.3.6 with the high
allocation success rates it was 8140 pages/second.  Direct velocity is
higher as a result of patch 2 of the series but this is expected and is
acceptable.  The direct reclaim and kswapd velocities change very little.

If these get accepted for merging then there is a difficulty in how they
should be handled.  7db8889a ("mm: have order > 0 compaction start off
where it left") is broken but it is already in 3.6-rc1 and needs to be
fixed.  However, if just patch 4 from this series is applied then Jim
Schutt's workload is known to break again as his workload also requires
patch 5.  While it would be preferred to have all these patches in 3.6 to
improve compaction in general, it would at least be acceptable if just
patches 4 and 5 were merged to 3.6 to fix a known problem without breaking
compaction completely.  On the face of it, that would force
__GFP_NO_KSWAPD patches to be merged at the same time but I can do a
version of this series with __GFP_NO_KSWAPD change reverted and then
rebase it on top of this series.  That might be best overall because I
note that the __GFP_NO_KSWAPD patch should have removed
deferred_compaction from page_alloc.c but it didn't but fixing that causes
collisions with this series.

This patch:

The comment about order applied when the check was order >
PAGE_ALLOC_COSTLY_ORDER which has not been the case since c5a73c3d ("thp:
use compaction for all allocation orders").  Fixing the comment while I'm
in the general area.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm/mmap.c: replace find_vma_prepare() with clearer find_vma_links()
Hugh Dickins [Mon, 8 Oct 2012 23:29:07 +0000 (16:29 -0700)]
mm/mmap.c: replace find_vma_prepare() with clearer find_vma_links()

People get confused by find_vma_prepare(), because it doesn't care about
what it returns in its output args, when its callers won't be interested.

Clarify by passing in end-of-range address too, and returning failure if
any existing vma overlaps the new range: instead of returning an ambiguous
vma which most callers then must check.  find_vma_links() is a clearer
name.

This does revert 2.6.27's dfe195fb79e88 ("mm: fix uninitialized variables
for find_vma_prepare callers"), but it looks like gcc 4.3.0 was one of
those releases too eager to shout about uninitialized variables: only
copy_vma() warns with 4.5.1 and 4.7.1, which a BUG on error silences.

[hughd@google.com: fix warning, remove BUG()]
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Benny Halevy <bhalevy@tonian.com>
Acked-by: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: fix nonuniform page status when writing new file with small buffer
Robin Dong [Mon, 8 Oct 2012 23:29:05 +0000 (16:29 -0700)]
mm: fix nonuniform page status when writing new file with small buffer

When writing a new file with 2048 bytes buffer, such as write(fd, buffer,
2048), it will call generic_perform_write() twice for every page:

write_begin
mark_page_accessed(page)
write_end

write_begin
mark_page_accessed(page)
write_end

Pages 1-13 will be added to lru-pvecs in write_begin() and will *NOT* be
added to active_list even they have be accessed twice because they are not
PageLRU(page).  But when page 14th comes, all pages in lru-pvecs will be
moved to inactive_list (by __lru_cache_add() ) in first write_begin(), now
page 14th *is* PageLRU(page).  And after second write_end() only page 14th
will be in active_list.

In Hadoop environment, we do comes to this situation: after writing a
file, we find out that only 14th, 28th, 42th...  page are in active_list
and others in inactive_list.  Now kswapd works, shrinks the inactive_list,
the file only have 14th, 28th...pages in memory, the readahead request
size will be broken to only 52k (13*4k), system's performance falls
dramatically.

This problem can also replay by below steps (the machine has 8G memory):

1. dd if=/dev/zero of=/test/file.out bs=1024 count=1048576
2. cat another 7.5G file to /dev/null
3. vmtouch -m 1G -v /test/file.out, it will show:

/test/file.out
[oooooooooooooooooooOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO] 187847/262144

the 'o' means same pages are in memory but same are not.

The solution for this problem is simple: the 14th page should be added to
lru_add_pvecs before mark_page_accessed() just as other pages.

[akpm@linux-foundation.org: tweak comment]
[akpm@linux-foundation.org: grab better comment from the v3 patch]
Signed-off-by: Robin Dong <sanbai@taobao.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: kill vma flag VM_RESERVED and mm->reserved_vm counter
Konstantin Khlebnikov [Mon, 8 Oct 2012 23:29:02 +0000 (16:29 -0700)]
mm: kill vma flag VM_RESERVED and mm->reserved_vm counter

A long time ago, in v2.4, VM_RESERVED kept swapout process off VMA,
currently it lost original meaning but still has some effects:

 | effect                 | alternative flags
-+------------------------+---------------------------------------------
1| account as reserved_vm | VM_IO
2| skip in core dump      | VM_IO, VM_DONTDUMP
3| do not merge or expand | VM_IO, VM_DONTEXPAND, VM_HUGETLB, VM_PFNMAP
4| do not mlock           | VM_IO, VM_DONTEXPAND, VM_HUGETLB, VM_PFNMAP

This patch removes reserved_vm counter from mm_struct.  Seems like nobody
cares about it, it does not exported into userspace directly, it only
reduces total_vm showed in proc.

Thus VM_RESERVED can be replaced with VM_IO or pair VM_DONTEXPAND | VM_DONTDUMP.

remap_pfn_range() and io_remap_pfn_range() set VM_IO|VM_DONTEXPAND|VM_DONTDUMP.
remap_vmalloc_range() set VM_DONTEXPAND | VM_DONTDUMP.

[akpm@linux-foundation.org: drivers/vfio/pci/vfio_pci.c fixup]
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Venkatesh Pallipadi <venki@google.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: prepare VM_DONTDUMP for using in drivers
Konstantin Khlebnikov [Mon, 8 Oct 2012 23:28:59 +0000 (16:28 -0700)]
mm: prepare VM_DONTDUMP for using in drivers

Rename VM_NODUMP into VM_DONTDUMP: this name matches other negative flags:
VM_DONTEXPAND, VM_DONTCOPY.  Currently this flag used only for
sys_madvise.  The next patch will use it for replacing the outdated flag
VM_RESERVED.

Also forbid madvise(MADV_DODUMP) for special kernel mappings VM_SPECIAL
(VM_IO | VM_DONTEXPAND | VM_RESERVED | VM_PFNMAP)

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Venkatesh Pallipadi <venki@google.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: kill vma flag VM_EXECUTABLE and mm->num_exe_file_vmas
Konstantin Khlebnikov [Mon, 8 Oct 2012 23:28:54 +0000 (16:28 -0700)]
mm: kill vma flag VM_EXECUTABLE and mm->num_exe_file_vmas

Currently the kernel sets mm->exe_file during sys_execve() and then tracks
number of vmas with VM_EXECUTABLE flag in mm->num_exe_file_vmas, as soon
as this counter drops to zero kernel resets mm->exe_file to NULL.  Plus it
resets mm->exe_file at last mmput() when mm->mm_users drops to zero.

VMA with VM_EXECUTABLE flag appears after mapping file with flag
MAP_EXECUTABLE, such vmas can appears only at sys_execve() or after vma
splitting, because sys_mmap ignores this flag.  Usually binfmt module sets
mm->exe_file and mmaps executable vmas with this file, they hold
mm->exe_file while task is running.

comment from v2.6.25-6245-g925d1c4 ("procfs task exe symlink"),
where all this stuff was introduced:

> The kernel implements readlink of /proc/pid/exe by getting the file from
> the first executable VMA.  Then the path to the file is reconstructed and
> reported as the result.
>
> Because of the VMA walk the code is slightly different on nommu systems.
> This patch avoids separate /proc/pid/exe code on nommu systems.  Instead of
> walking the VMAs to find the first executable file-backed VMA we store a
> reference to the exec'd file in the mm_struct.
>
> That reference would prevent the filesystem holding the executable file
> from being unmounted even after unmapping the VMAs.  So we track the number
> of VM_EXECUTABLE VMAs and drop the new reference when the last one is
> unmapped.  This avoids pinning the mounted filesystem.

exe_file's vma accounting is hooked into every file mmap/unmmap and vma
split/merge just to fix some hypothetical pinning fs from umounting by mm,
which already unmapped all its executable files, but still alive.

Seems like currently nobody depends on this behaviour.  We can try to
remove this logic and keep mm->exe_file until final mmput().

mm->exe_file is still protected with mm->mmap_sem, because we want to
change it via new sys_prctl(PR_SET_MM_EXE_FILE).  Also via this syscall
task can change its mm->exe_file and unpin mountpoint explicitly.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Venkatesh Pallipadi <venki@google.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: use mm->exe_file instead of first VM_EXECUTABLE vma->vm_file
Konstantin Khlebnikov [Mon, 8 Oct 2012 23:28:51 +0000 (16:28 -0700)]
mm: use mm->exe_file instead of first VM_EXECUTABLE vma->vm_file

Some security modules and oprofile still uses VM_EXECUTABLE for retrieving
a task's executable file.  After this patch they will use mm->exe_file
directly.  mm->exe_file is protected with mm->mmap_sem, so locking stays
the same.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Acked-by: Chris Metcalf <cmetcalf@tilera.com> [arch/tile]
Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> [tomoyo]
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Acked-by: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Venkatesh Pallipadi <venki@google.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: kill vma flag VM_CAN_NONLINEAR
Konstantin Khlebnikov [Mon, 8 Oct 2012 23:28:46 +0000 (16:28 -0700)]
mm: kill vma flag VM_CAN_NONLINEAR

Move actual pte filling for non-linear file mappings into the new special
vma operation: ->remap_pages().

Filesystems must implement this method to get non-linear mapping support,
if it uses filemap_fault() then generic_file_remap_pages() can be used.

Now device drivers can implement this method and obtain nonlinear vma support.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com> #arch/tile
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Venkatesh Pallipadi <venki@google.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: kill vma flag VM_INSERTPAGE
Konstantin Khlebnikov [Mon, 8 Oct 2012 23:28:40 +0000 (16:28 -0700)]
mm: kill vma flag VM_INSERTPAGE

Merge VM_INSERTPAGE into VM_MIXEDMAP.  VM_MIXEDMAP VMA can mix pure-pfn
ptes, special ptes and normal ptes.

Now copy_page_range() always copies VM_MIXEDMAP VMA on fork like
VM_PFNMAP.  If driver populates whole VMA at mmap() it probably not
expects page-faults.

This patch removes special check from vma_wants_writenotify() which
disables pages write tracking for VMA populated via vm_instert_page().
BDI below mapped file should not use dirty-accounting, moreover
do_wp_page() can handle this.

vm_insert_page() still marks vma after first usage.  Usually it is called
from f_op->mmap() handler under mm->mmap_sem write-lock, so it able to
change vma->vm_flags.  Caller must set VM_MIXEDMAP at mmap time if it
wants to call this function from other places, for example from page-fault
handler.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Venkatesh Pallipadi <venki@google.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: introduce arch-specific vma flag VM_ARCH_1
Konstantin Khlebnikov [Mon, 8 Oct 2012 23:28:37 +0000 (16:28 -0700)]
mm: introduce arch-specific vma flag VM_ARCH_1

Combine several arch-specific vma flags into one.

before patch:

        0x00000200      0x01000000      0x20000000      0x40000000
x86     VM_NOHUGEPAGE   VM_HUGEPAGE     -               VM_PAT
powerpc -               -               VM_SAO          -
parisc  VM_GROWSUP      -               -               -
ia64    VM_GROWSUP      -               -               -
nommu   -               VM_MAPPED_COPY  -               -
others  -               -               -               -

after patch:

        0x00000200      0x01000000      0x20000000      0x40000000
x86     -               VM_PAT          VM_HUGEPAGE     VM_NOHUGEPAGE
powerpc -               VM_SAO          -               -
parisc  -               VM_GROWSUP      -               -
ia64    -               VM_GROWSUP      -               -
nommu   -               VM_MAPPED_COPY  -               -
others  -               VM_ARCH_1       -               -

And voila! One completely free bit.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Venkatesh Pallipadi <venki@google.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm, x86, pat: rework linear pfn-mmap tracking
Konstantin Khlebnikov [Mon, 8 Oct 2012 23:28:34 +0000 (16:28 -0700)]
mm, x86, pat: rework linear pfn-mmap tracking

Replace the generic vma-flag VM_PFN_AT_MMAP with x86-only VM_PAT.

We can toss mapping address from remap_pfn_range() into
track_pfn_vma_new(), and collect all PAT-related logic together in
arch/x86/.

This patch also restores orignal frustration-free is_cow_mapping() check
in remap_pfn_range(), as it was before commit v2.6.28-rc8-88-g3c8bb73
("x86: PAT: store vm_pgoff for all linear_over_vma_region mappings - v3")

is_linear_pfn_mapping() checks can be removed from mm/huge_memory.c,
because it already handled by VM_PFNMAP in VM_NO_THP bit-mask.

[suresh.b.siddha@intel.com: Reset the VM_PAT flag as part of untrack_pfn_vma()]
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Venkatesh Pallipadi <venki@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Venkatesh Pallipadi <venki@google.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agox86, pat: separate the pfn attribute tracking for remap_pfn_range and vm_insert_pfn
Suresh Siddha [Mon, 8 Oct 2012 23:28:29 +0000 (16:28 -0700)]
x86, pat: separate the pfn attribute tracking for remap_pfn_range and vm_insert_pfn

With PAT enabled, vm_insert_pfn() looks up the existing pfn memory
attribute and uses it.  Expectation is that the driver reserves the
memory attributes for the pfn before calling vm_insert_pfn().

remap_pfn_range() (when called for the whole vma) will setup a new
attribute (based on the prot argument) for the specified pfn range.
This addresses the legacy usage which typically calls remap_pfn_range()
with a desired memory attribute.  For ranges smaller than the vma size
(which is typically not the case), remap_pfn_range() will use the
existing memory attribute for the pfn range.

Expose two different API's for these different behaviors.
track_pfn_insert() for tracking the pfn attribute set by vm_insert_pfn()
and track_pfn_remap() for the remap_pfn_range().

This cleanup also prepares the ground for the track/untrack pfn vma
routines to take over the ownership of setting PAT specific vm_flag in
the 'vma'.

[khlebnikov@openvz.org: Clear checks in track_pfn_remap()]
[akpm@linux-foundation.org: tweak a few comments]
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Venkatesh Pallipadi <venki@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agox86, pat: remove the dependency on 'vm_pgoff' in track/untrack pfn vma routines
Suresh Siddha [Mon, 8 Oct 2012 23:28:23 +0000 (16:28 -0700)]
x86, pat: remove the dependency on 'vm_pgoff' in track/untrack pfn vma routines

'pfn' argument for track_pfn_vma_new() can be used for reserving the
attribute for the pfn range.  No need to depend on 'vm_pgoff'

Similarly, untrack_pfn_vma() can depend on the 'pfn' argument if it is
non-zero or can use follow_phys() to get the starting value of the pfn
range.

Also the non zero 'size' argument can be used instead of recomputing it
from vma.

This cleanup also prepares the ground for the track/untrack pfn vma
routines to take over the ownership of setting PAT specific vm_flag in the
'vma'.

[khlebnikov@openvz.org: Clear pfn to paddr conversion]
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Venkatesh Pallipadi <venki@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agomm: remove __GFP_NO_KSWAPD
Rik van Riel [Mon, 8 Oct 2012 23:28:21 +0000 (16:28 -0700)]
mm: remove __GFP_NO_KSWAPD

When transparent huge pages were introduced, memory compaction and swap
storms were an issue, and the kernel had to be careful to not make THP
allocations cause pageout or compaction.

Now that we have working compaction deferral, kswapd is smart enough to
invoke compaction and the quadratic behaviour around isolate_free_pages
has been fixed, it should be safe to remove __GFP_NO_KSWAPD.

[minchan@kernel.org: Comment fix]
[mgorman@suse.de: Avoid direct reclaim for deferred compaction]
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agoCPU hotplug, debug: detect imbalance between get_online_cpus() and put_online_cpus()
Srivatsa S. Bhat [Mon, 8 Oct 2012 23:28:20 +0000 (16:28 -0700)]
CPU hotplug, debug: detect imbalance between get_online_cpus() and put_online_cpus()

The synchronization between CPU hotplug readers and writers is achieved
by means of refcounting, safeguarded by the cpu_hotplug.lock.

get_online_cpus() increments the refcount, whereas put_online_cpus()
decrements it.  If we ever hit an imbalance between the two, we end up
compromising the guarantees of the hotplug synchronization i.e, for
example, an extra call to put_online_cpus() can end up allowing a
hotplug reader to execute concurrently with a hotplug writer.

So, add a WARN_ON() in put_online_cpus() to detect such cases where the
refcount can go negative, and also attempt to fix it up, so that we can
continue to run.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agoKconfig: clean up the "#if defined(arch)" list for exception-trace sysctl entry
Catalin Marinas [Mon, 8 Oct 2012 23:28:16 +0000 (16:28 -0700)]
Kconfig: clean up the "#if defined(arch)" list for exception-trace sysctl entry

Introduce SYSCTL_EXCEPTION_TRACE config option and selec it in the
architectures requiring support for the "exception-trace" debug_table
entry in kernel/sysctl.c.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agoKconfig: clean up the long arch list for the DEBUG_BUGVERBOSE config option
Catalin Marinas [Mon, 8 Oct 2012 23:28:13 +0000 (16:28 -0700)]
Kconfig: clean up the long arch list for the DEBUG_BUGVERBOSE config option

Introduce HAVE_DEBUG_BUGVERBOSE config option and select it in
corresponding architecture Kconfig files.  Architectures that already
select GENERIC_BUG don't need to select HAVE_DEBUG_BUGVERBOSE.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agoKconfig: clean up the long arch list for the DEBUG_KMEMLEAK config option
Catalin Marinas [Mon, 8 Oct 2012 23:28:11 +0000 (16:28 -0700)]
Kconfig: clean up the long arch list for the DEBUG_KMEMLEAK config option

Introduce HAVE_DEBUG_KMEMLEAK config option and select it in corresponding
architecture Kconfig files.  DEBUG_KMEMLEAK now only depends on
HAVE_DEBUG_KMEMLEAK.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agoKconfig: clean up the long arch list for the UID16 config option
Catalin Marinas [Mon, 8 Oct 2012 23:28:08 +0000 (16:28 -0700)]
Kconfig: clean up the long arch list for the UID16 config option

Introduce HAVE_UID16 config option and select it in corresponding
architecture Kconfig files.  UID16 now only depends on HAVE_UID16.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agoMAINTAINERS: add Konrad as the SWIOTLB maintainer
Konrad Rzeszutek Wilk [Mon, 8 Oct 2012 23:28:05 +0000 (16:28 -0700)]
MAINTAINERS: add Konrad as the SWIOTLB maintainer

Now that I've an IA64 box on top of the other boxes (IBM with Calgary-X,
Intel VT-d, AMD Vi, and AMD GART - that can use SWIOTLB as fallback) I can
reliably do regression testing.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agoMerge tag 'sound-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Linus Torvalds [Mon, 8 Oct 2012 22:07:14 +0000 (07:07 +0900)]
Merge tag 'sound-3.7' of git://git./linux/kernel/git/tiwai/sound

Pull sound updates from Takashi Iwai:
 "This contains pretty many small commits covering fairly large range of
  files in sound/ directory.  Partly because of additional API support
  and partly because of constantly developed ASoC and ARM stuff.

  Some highlights:

   - Introduced the helper function and documentation for exposing the
     channel map via control API, as discussed in Plumbers; most of PCI
     drivers are covered, will follow more drivers later

   - Most of drivers have been replaced with the new PM callbacks (if
     the bus is supported)

   - HD-audio controller got the support of runtime PM and the support
     of D3 clock-stop.  Also changing the power_save option in sysfs
     kicks off immediately to enable / disable the power-save mode.

   - Another significant code change in HD-audio is the rewrite of
     firmware loading code.  Other than that, most of changes in
     HD-audio are continued cleanups and standardization for the generic
     auto parser and bug fixes (HBR, device-specific fixups), in
     addition to the support of channel-map API.

   - Addition of ASoC bindings for the compressed API, used by the
     mid-x86 drivers.

   - Lots of cleanups and API refreshes for ASoC codec drivers and
     DaVinci.

   - Conversion of OMAP to dmaengine.

   - New machine driver for Wolfson Microelectronics Bells.

   - New CODEC driver for Wolfson Microelectronics WM0010.

   - Enhancements to the ux500 and wm2000 drivers

   - A new driver for DA9055 and the support for regulator bypass mode."

Fix up various arm soc header file reorg conflicts.

* tag 'sound-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (339 commits)
  ALSA: hda - Add new codec ALC283 ALC290 support
  ALSA: hda - avoid unneccesary indices on "Headphone Jack" controls
  ALSA: hda - fix indices on boost volume on Conexant
  ALSA: aloop - add locking to timer access
  ALSA: hda - Fix hang caused by race during suspend.
  sound: Remove unnecessary semicolon
  ALSA: hda/realtek - Fix detection of ALC271X codec
  ALSA: hda - Add inverted internal mic quirk for Lenovo IdeaPad U310
  ALSA: hda - make Realtek/Sigmatel/Conexant use the generic unsol event
  ALSA: hda - make a generic unsol event handler
  ASoC: codecs: Add DA9055 codec driver
  ASoC: eukrea-tlv320: Convert it to platform driver
  ALSA: ASoC: add DT bindings for CS4271
  ASoC: wm_hubs: Ensure volume updates are handled during class W startup
  ASoC: wm5110: Adding missing volume update bits
  ASoC: wm5110: Add OUT3R support
  ASoC: wm5110: Add AEC loopback support
  ASoC: wm5110: Rename EPOUT to HPOUT3
  ASoC: arizona: Add more clock rates
  ASoC: arizona: Add more DSP options for mixer input muxes
  ...

12 years agoexec: make de_thread() killable
Oleg Nesterov [Mon, 8 Oct 2012 17:13:01 +0000 (19:13 +0200)]
exec: make de_thread() killable

Change de_thread() to use KILLABLE rather than UNINTERRUPTIBLE while
waiting for other threads.  The only complication is that we should
clear ->group_exit_task and ->notify_count before we return, and we
should do this under tasklist_lock.  -EAGAIN is used to match the
initial signal_group_exit() check/return, it doesn't really matter.

This fixes the (unlikely) race with coredump.  de_thread() checks
signal_group_exit() before it starts to kill the subthreads, but this
can't help if another CLONE_VM (but non CLONE_THREAD) task starts the
coredumping after de_thread() unlocks ->siglock.  In this case the
killed sub-thread can block in exit_mm() waiting for coredump_finish(),
execing thread waits for that sub-thead, and the coredumping thread
waits for execing thread.  Deadlock.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agoMerge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas...
Linus Torvalds [Mon, 8 Oct 2012 21:41:12 +0000 (06:41 +0900)]
Merge tag 'arm64-fixes' of git://git./linux/kernel/git/cmarinas/linux-aarch64

Pull arm64 changes from Catalin Marinas:
 "arm64 fixes:
   - Use swiotlb_init() instead of swiotlb_init_with_default_size().
     The latter is now a static function (commit 74838b75379a "swiotlb:
     add the late swiotlb initialization function with iotlb memory").
   - Enable interrupts before calling do_notify_resume().

  arm64 clean-up:
   - Use the generic implementation of compat_sys_sendfile() on arm64 as
     commit 8f9c0119d7ba (introducing the function) has been merged."

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64:
  arm64: Enable interrupts before calling do_notify_resume()
  arm64: Use the generic compat_sys_sendfile() implementation
  arm64: Call swiotlb_init() instead of swiotlb_init_with_default_size()

12 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
Linus Torvalds [Mon, 8 Oct 2012 21:39:30 +0000 (06:39 +0900)]
Merge git://git./linux/kernel/git/davem/sparc

Pull sparc changes from David S Miller:
 "There is an attempt to fix a bad interaction between syscall tracing
  and force_successful_syscall() from Al Viro, but it needs to be redone
  as it introduced regressions and thus had to be reverted for now.

  Al is working on an updated version.

  But what we do have here are some significant bzero/memset
  improvements for Niagara-4.  An 8K page can be cleared in around 600
  cycles, because we essentially have a store that behaves like
  powerpc's dcbz that we can actually make real use of."

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  Revert strace hiccups fix.
  sparc64: Niagara-4 bzero/memset, plus use MRU stores in page copy.
  sparc64: Fix strace hiccups when force_successful_syscall() triggers.
  sparc64: Rearrange thread info to cheaply clear syscall noerror state.

12 years agoarm64: Enable interrupts before calling do_notify_resume()
Catalin Marinas [Mon, 8 Oct 2012 17:04:21 +0000 (18:04 +0100)]
arm64: Enable interrupts before calling do_notify_resume()

task_work_run() implementation had the side effect of enabling
interrupts. With commit ac3d0da8 (task_work: Make task_work_add()
lockless), interrupts are no longer enabled revealing the bug in the
arch code. This patch enables the interrupt explicitly before calling
do_notify_resume().

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
12 years agoarm64: Use the generic compat_sys_sendfile() implementation
Catalin Marinas [Wed, 3 Oct 2012 10:20:20 +0000 (11:20 +0100)]
arm64: Use the generic compat_sys_sendfile() implementation

The generic implementation of compat_sys_sendfile() has been introduced
by commit 8f9c0119. This patch removes the arm64 implementation in
favour of the generic one.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
12 years agoarm64: Call swiotlb_init() instead of swiotlb_init_with_default_size()
Catalin Marinas [Wed, 3 Oct 2012 13:35:18 +0000 (14:35 +0100)]
arm64: Call swiotlb_init() instead of swiotlb_init_with_default_size()

Following commit 74838b7 (swiotlb: add the late swiotlb initialization
function with iotlb memory) the swiotlb_init_with_default_size() is a
static function. This patch changes the arm64 code to call
swiotlb_init() instead and use the default size of 64MB. It is assumed
that AArch64 platforms have enough RAM to afford the pre-allocated
swiotlb memory. It also removes the #ifdef around this call since
CONFIG_SWIOTLB is always enabled.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
12 years agoMerge tag 'upstream-3.7-rc1-fastmap' of git://git.infradead.org/linux-ubi
Linus Torvalds [Mon, 8 Oct 2012 11:40:45 +0000 (20:40 +0900)]
Merge tag 'upstream-3.7-rc1-fastmap' of git://git.infradead.org/linux-ubi

Pull UBI fastmap changes from Artem Bityutskiy:
 "This pull request contains the UBI fastmap support implemented by
  Richard Weinberger from Linutronix.  Fastmap is designed to address
  UBI's slow scanning issues.  Namely, it introduces a new on-flash
  data-structure called "fastmap", which stores the information about
  logical<->physical eraseblocks mappings.  So now to get this
  information just read the fastmap, instead of doing full scan.  More
  information here can be found in Richard's announcement in LKML
  (Subject: UBI: Fastmap request for inclusion (v19)):

     http://thread.gmane.org/gmane.linux.kernel/1364922/focus=1369109

  One thing I want to explicitly say is that fastmap did not have large
  enough linux-next exposure.  It is partially my fault - I did not
  respond quickly enough.  I _really_ apologize for this.  But it had
  good testing and disabled by default, so I do not expect that we'll
  break anything.

  Fastmap is declared as experimental so far, and it is off by default.
  We did declare that the on-flash format may be changed.  The reason
  for this is that no one used it in real production so far, so there is
  a high risk that something is missing.  Besides, we do not have
  user-space tools supporting fastmap so far.

  Nevertheless, I suggest we merge this feature.  Many people want UBI's
  scanning bottleneck to be fixed and merging fastmap now should
  accelerate its production use.  The plan is to make it bullet-prove,
  somewhat clean-up, and make it the default for UBI.  I do not know how
  many kernel releases will it take.

  Basically, I what I want to do for fastmap is something like Linus did
  for btrfs few years ago."

* tag 'upstream-3.7-rc1-fastmap' of git://git.infradead.org/linux-ubi:
  UBI: Wire-up fastmap
  UBI: Add fastmap core
  UBI: Add fastmap support to the WL sub-system
  UBI: Add fastmap stuff to attach.c
  UBI: Wire-up ->fm_sem
  UBI: Add fastmap bits to build.c
  UBI: Add self_check_eba()
  UBI: Export next_sqnum()
  UBI: Add fastmap stuff to ubi.h
  UBI: Add fastmap on-flash data structures

12 years agoMerge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux
Linus Torvalds [Mon, 8 Oct 2012 07:19:32 +0000 (16:19 +0900)]
Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux

Pill drm updates part 2 from Dave Airlie:
 "This is the follow-up pull, 3 pieces

  a) exynos next stuff, was delayed but looks okay to me, one patch in
     v4l bits but it was acked by v4l person.
  b) UAPI disintegration bits
  c) intel fixes - DP fixes, hang fixes, other misc fixes."

* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (52 commits)
  drm: exynos: hdmi: remove drm common hdmi platform data struct
  drm: exynos: hdmi: add support for exynos5 hdmi
  drm: exynos: hdmi: replace is_v13 with version check in hdmi
  drm: exynos: hdmi: add support for exynos5 mixer
  drm: exynos: hdmi: add support to disable video processor in mixer
  drm: exynos: hdmi: add support for platform variants for mixer
  drm: exynos: hdmi: add support for exynos5 hdmiphy
  drm: exynos: hdmi: add support for exynos5 ddc
  drm: exynos: remove drm hdmi platform data struct
  drm: exynos: hdmi: turn off HPD interrupt in HDMI chip
  drm: exynos: hdmi: use s5p-hdmi platform data
  drm: exynos: hdmi: fix interrupt handling
  drm: exynos: hdmi: support for platform variants
  media: s5p-hdmi: add HPD GPIO to platform data
  UAPI: (Scripted) Disintegrate include/drm
  drm/i915: Fix GT_MODE default value
  drm/i915: don't frob the vblank ts in finish_page_flip
  drm/i915: call drm_handle_vblank before finish_page_flip
  drm/i915: print warning if vmi915_gem_fault error is not handled
  drm/i915: EBUSY status handling added to i915_gem_fault().
  ...

12 years agoMerge branch 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Linus Torvalds [Sun, 7 Oct 2012 22:56:10 +0000 (07:56 +0900)]
Merge branch 'rc-fixes' of git://git./linux/kernel/git/mmarek/kbuild

Pull kbuild fixes from Michal Marek:
 "Here are two fixes I intended to send after v3.6-rc7, but failed to do
  so.  So please pull them for v3.7-rc1 and they will be picked up by
  stable.

  The first one fixes gcc -x <language> syntax in various build-time
  tests, which icecream and possible other gcc wrappers did not
  understand (and yes, icecream is going to be fixed as well).

  The second one fixes make tar-pkg so that unpacking the tarball does
  not replace the /lib -> /usr/lib symlink on recent Fedora releases."

* 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kbuild: Fix gcc -x syntax
  kbuild: Do not package /boot and /lib in make tar-pkg

12 years agolocalmodconfig: Document localmodconfig in README
Steven Rostedt [Fri, 5 Oct 2012 20:52:50 +0000 (16:52 -0400)]
localmodconfig: Document localmodconfig in README

Someone (over a year ago :-p) asked me to document localmodconfig in the
README file in the source code.  I thought it was a good idea but other
things were more important and I simply forgot about it.  Well, I
stumbled on the email asking me about this and I'm sending it out now.

Signed-off-by: Steven "Mr. Procrastinator" Rostedt <rostedt@goodmis.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
12 years agoMerge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux
Linus Torvalds [Sun, 7 Oct 2012 22:14:06 +0000 (07:14 +0900)]
Merge branch 'release' of git://git./linux/kernel/git/lenb/linux

Pul ACPI & Power Management updates from Len Brown:
 - acpidump utility added
 - intel_idle driver now supports IVB Xeon
 - turbostat utility can now count SMIs
 - ACPI can now bind to USB3 hubs
 - misc fixes

* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux: (49 commits)
  ACPI: Add new sysfs interface to export device description
  ACPI: Harden acpi_table_parse_entries() against BIOS bug
  tools/power/turbostat: add option to count SMIs, re-name some options
  tools/power turbostat: add [-d MSR#][-D MSR#] options to print counter deltas
  intel_idle: enable IVB Xeon support
  tools/power turbostat: add [-m MSR#] option
  tools/power turbostat: make -M output pretty
  tools/power turbostat: print more turbo-limit information
  tools/power turbostat: delete unused line
  tools/power turbostat: run on IVB Xeon
  tools/power/acpi/acpidump: create acpidump(8), local make install targets
  tools/power/acpi/acpidump: version 20101221 - find dynamic tables in sysfs
  ACPI: run _OSC after ACPI_FULL_INITIALIZATION
  tools/power/acpi/acpidump: create acpidump(8), local make install targets
  tools/power/acpi/acpidump: version 20101221 - find dynamic tables in sysfs
  tools/power/acpi/acpidump: version 20071116
  tools/power/acpi/acpidump: version 20070714
  tools/power/acpi/acpidump: version 20060606
  tools/power/acpi/acpidump: version 20051111
  xo15-ebook: convert to module_acpi_driver()
  ...

12 years agoMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph...
Linus Torvalds [Sun, 7 Oct 2012 21:38:18 +0000 (06:38 +0900)]
Merge branch 'for-linus' of git://git./linux/kernel/git/sage/ceph-client

Pull ceph updates from Sage Weil:
 "The bulk of this pull is a series from Alex that refactors and cleans
  up the RBD code to lay the groundwork for supporting the new image
  format and evolving feature set.  There are also some cleanups in
  libceph, and for ceph there's fixed validation of file striping
  layouts and a bugfix in the code handling a shrinking MDS cluster."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (71 commits)
  ceph: avoid 32-bit page index overflow
  ceph: return EIO on invalid layout on GET_DATALOC ioctl
  rbd: BUG on invalid layout
  ceph: propagate layout error on osd request creation
  libceph: check for invalid mapping
  ceph: convert to use le32_add_cpu()
  ceph: Fix oops when handling mdsmap that decreases max_mds
  rbd: update remaining header fields for v2
  rbd: get snapshot name for a v2 image
  rbd: get the snapshot context for a v2 image
  rbd: get image features for a v2 image
  rbd: get the object prefix for a v2 rbd image
  rbd: add code to get the size of a v2 rbd image
  rbd: lay out header probe infrastructure
  rbd: encapsulate code that gets snapshot info
  rbd: add an rbd features field
  rbd: don't use index in __rbd_add_snap_dev()
  rbd: kill create_snap sysfs entry
  rbd: define rbd_dev_image_id()
  rbd: define some new format constants
  ...

12 years agoMerge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso...
Linus Torvalds [Sun, 7 Oct 2012 21:36:39 +0000 (06:36 +0900)]
Merge tag 'ext4_for_linus' of git://git./linux/kernel/git/tytso/ext4

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
  ...

12 years agoMerge branch 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvar...
Linus Torvalds [Sun, 7 Oct 2012 21:35:17 +0000 (06:35 +0900)]
Merge branch 'i2c-for-linus' of git://git./linux/kernel/git/jdelvare/staging

Pull i2c updates from Jean Delvare:
 "Most visible changes are the SMBus multiplexing support added to the
  i2c-i801 driver, as well as support for the VIA VX900."

* 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
  i2c-piix4: Fix build failure
  i2c: Correct struct i2c_driver doc about detection
  i2c-i801: Let i2c-mux-gpio find the GPIO chip
  i2c-mux-gpio: Update documentation
  i2c-mux-gpio: Add support for dynamically allocated GPIO pins
  i2c-mux-gpio: Use devm_kzalloc instead of kzalloc
  i2c-i801: Support SMBus multiplexing on Asus Z8 series
  i2c-viapro: Add VIA VX900 device ID
  i2c-parport: i2c_parport_irq can be static
  i2c-designware: i2c_dw_xfer_msg can be static
  i2c/scx200_*: Replace printks with pr_<level>s
  i2c: Make I2C available on UML
  i2c: Convert struct i2c_msg initialization to C99 format
  i2c-smbus: Convert kzalloc to devm_kzalloc
  i2c-mux: Add support for device auto-detection

12 years agoMerge tag 'iommu-updates-v3.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Sun, 7 Oct 2012 21:33:44 +0000 (06:33 +0900)]
Merge tag 'iommu-updates-v3.7-rc1' of git://git./linux/kernel/git/joro/iommu

Pull IOMMU updates from Joerg Roedel:
 "This time the IOMMU updates contain a bunch of fixes and cleanups to
  various IOMMU drivers and the DMA debug code.  New features are the
  code for IRQ remapping support with the AMD IOMMU (preperation for
  that was already merged in the last release) and a debugfs interface
  to export some statistics in the NVidia Tegra IOMMU driver."

* tag 'iommu-updates-v3.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (27 commits)
  iommu/amd: Remove obsolete comment line
  dma-debug: Remove local BUS_NOTIFY_UNBOUND_DRIVER define
  iommu/amd: Fix possible use after free in get_irq_table()
  iommu/amd: Report irq remapping through IOMMU-API
  iommu/amd: Print message to system log when irq remapping is enabled
  iommu/irq: Use amd_iommu_irq_ops if supported
  iommu/amd: Make sure irq remapping still works on dma init failure
  iommu/amd: Add initialization routines for AMD interrupt remapping
  iommu/amd: Add call-back routine for HPET MSI
  iommu/amd: Implement MSI routines for interrupt remapping
  iommu/amd: Add IOAPIC remapping routines
  iommu/amd: Add routines to manage irq remapping tables
  iommu/amd: Add IRTE invalidation routine
  iommu/amd: Make sure IOMMU is not considered to translate itself
  iommu/amd: Split device table initialization into irq and dma part
  iommu/amd: Check if IOAPIC information is correct
  iommu/amd: Allocate data structures to keep track of irq remapping tables
  iommu/amd: Add slab-cache for irq remapping tables
  iommu/amd: Keep track of HPET and IOAPIC device ids
  iommu/amd: Fix features reporting
  ...

12 years agoMerge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm
Linus Torvalds [Sun, 7 Oct 2012 12:20:57 +0000 (21:20 +0900)]
Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm

Pull ARM updates from Russell King:
 "This is the first chunk of ARM updates for this merge window.
  Conflicts are expected in two files - asm/timex.h and
  mach-integrator/integrator_cp.c.  Nothing particularly stands out more
  than anything else.

  Most of the growth is down to the opcodes stuff from Dave Martin,
  which is countered by Rob's patches to use more of the asm-generic
  headers on ARM."

(A few more conflicts grew since then, but it all looked fairly trivial)

* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (44 commits)
  ARM: 7548/1: include linux/sched.h in syscall.h
  ARM: 7541/1: Add ARM ERRATA 775420 workaround
  ARM: ensure vm_struct has its phys_addr member filled in
  ARM: 7540/1: kexec: Check segment memory addresses
  ARM: 7539/1: kexec: scan for dtb magic in segments
  ARM: 7538/1: delay: add registration mechanism for delay timer sources
  ARM: 7536/1: smp: Formalize an IPI for wakeup
  ARM: 7525/1: ptrace: use updated syscall number for syscall auditing
  ARM: 7524/1: support syscall tracing
  ARM: 7519/1: integrator: convert platform devices to Device Tree
  ARM: 7518/1: integrator: convert AMBA devices to device tree
  ARM: 7517/1: integrator: initial device tree support
  ARM: 7516/1: plat-versatile: add DT support to FPGA IRQ
  ARM: 7515/1: integrator: check PL010 base address from resource
  ARM: 7514/1: integrator: call common init function from machine
  ARM: 7522/1: arch_timers: register a time/cycle counter
  ARM: 7523/1: arch_timers: enable the use of the virtual timer
  ARM: 7531/1: mark kernelmode mem{cpy,set} non-experimental
  ARM: 7520/1: Build dtb files in all target
  ARM: Fix build warning in arch/arm/mm/alignment.c
  ...

12 years agoMerge branch 'next' of git://git.monstr.eu/linux-2.6-microblaze
Linus Torvalds [Sun, 7 Oct 2012 12:08:40 +0000 (21:08 +0900)]
Merge branch 'next' of git://git.monstr.eu/linux-2.6-microblaze

Pull microblaze arch updates from Michal Simek.

* 'next' of git://git.monstr.eu/linux-2.6-microblaze:
  Revert "microblaze_mmu_v2: Update signal returning address"
  microblaze: Added more support for PCI
  microblaze: Prefer to use pr_XXX instead of printk(KERN_XX)
  microblaze: Fix bug with passing command line
  microblaze: Remove PAGE properties duplication
  microblaze: Remove additional andi which has been already done
  microblaze: Use predefined macro for ESR_DIZ
  microblaze: Support 4k/16k/64k pages
  microblaze: Do not used hardcoded value in exception handler
  microblaze: Added fdt chosen capability for timer
  microblaze: Add support for ioreadXX/iowriteXX_rep
  microblaze: Improve failure handling for GPIO reset
  microblaze: clinkage.h

12 years agoMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris...
Linus Torvalds [Sun, 7 Oct 2012 12:07:21 +0000 (21:07 +0900)]
Merge branch 'for-linus' of git://git./linux/kernel/git/jmorris/linux-security

Pull IMA bugfix (security subsystem) from James Morris.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  ima: fix bug in argument order

12 years agoMerge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu
Linus Torvalds [Sun, 7 Oct 2012 12:06:10 +0000 (21:06 +0900)]
Merge branch 'for-next' of git://git./linux/kernel/git/gerg/m68knommu

Pull m68knommu arch updates from Greg Ungerer:
 "Most of it is a cleanup of the ColdFire hardware header files.  We
  have had a few occurrances of bugs caused by inconsistent definitions
  of peripheral addresses.  These patches make them all consistent, and
  also clean out a bunch of old crap.  Overall we remove about 1000
  lines."

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu: (27 commits)
  m68knommu: fix inconsistent formating in ColdFire 5407 definitions
  m68knommu: fix inconsistent formating in ColdFire 5307 definitions
  m68knommu: fix inconsistent formating in ColdFire 527x definitions
  m68knommu: fix inconsistent formating in ColdFire 5272 definitions
  m68knommu: fix inconsistent formating in ColdFire 523x definitions
  m68knommu: clean up ColdFire 54xx General Timer definitions
  m68knommu: clean up Pin Assignment definitions for the 54xx ColdFire CPU
  m68knommu: fix multi-function pin setup for FEC module on ColdFire 523x
  m68knommu: move ColdFire slice timer address defiens to 54xx header
  m68knommu: use read/write IO access functions in ColdFire m532x setup code
  m68knommu: modify ColdFire 532x GPIO register definitions to be consistent
  m68knommu: remove a lot of unsed definitions for 532x ColdFire
  m68knommu: use definitions for the ColdFire 528x FEC multi-function pins
  m68knommu: remove address offsets relative to IPSBAR for ColdFire 527x
  m68knommu: remove unused ColdFire 5282 register definitions
  m68knommu: fix wrong register offsets used for ColdFire 5272 multi-function pins
  m68knommu: make ColdFire 5249 MBAR2 register definitions absolute addresses
  m68knommu: make remaining ColdFire 5272 register definitions absolute addresses
  m68knommu: make ColdFire Park and Assignment register definitions absolute addresses
  m68knommu: make ColdFire Chip Select register definitions absolute addresses
  ...