Currently we we use the lru head link of the second page of a compound page
to hold its destructor.  This was ok when it was purely an internal
implmentation detail.  However, hugetlbfs overrides this destructor
violating the layering.  Abstract this out as explicit calls, also
introduce a type for the callback function allowing them to be type
checked.  For each callback we pre-declare the function, causing a type
error on definition rather than on use elsewhere.

[akpm@osdl.org: cleanups]
Signed-off-by: NAndy Whitcroft <apw@shadowen.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Currently we simply attempt to allocate from all allowed nodes using
GFP_THISNODE.  However, GFP_THISNODE does not do reclaim (it wont do any at
all if the recent GFP_THISNODE patch is accepted).  If we truly run out of
memory in the whole system then fallback_alloc may return NULL although
memory may still be available if we would perform more thorough reclaim.

This patch changes fallback_alloc() so that we first only inspect all the
per node queues for available slabs.  If we find any then we allocate from
those.  This avoids slab fragmentation by first getting rid of all partial
allocated slabs on every node before allocating new memory.

If we cannot satisfy the allocation from any per node queue then we extend
a slab.  We now call into the page allocator without specifying
GFP_THISNODE.  The page allocator will then implement its own fallback (in
the given cpuset context), perform necessary reclaim (again considering not
a single node but the whole set of allowed nodes) and then return pages for
a new slab.

We identify from which node the pages were allocated and then insert the
pages into the corresponding per node structure.  In order to do so we need
to modify cache_grow() to take a parameter that specifies the new slab.
kmem_getpages() can no longer set the GFP_THISNODE flag since we need to be
able to use kmem_getpage to allocate from an arbitrary node.  GFP_THISNODE
needs to be specified when calling cache_grow().

One key advantage is that the decision from which node to allocate new
memory is removed from slab fallback processing.  The patch allows to go
back to use of the page allocators fallback/reclaim logic.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The intent of GFP_THISNODE is to make sure that an allocation occurs on a
particular node.  If this is not possible then NULL needs to be returned so
that the caller can choose what to do next on its own (the slab allocator
depends on that).

However, GFP_THISNODE currently triggers reclaim before returning a failure
(GFP_THISNODE means GFP_NORETRY is set).  If we have over allocated a node
then we will currently do some reclaim before returning NULL.  The caller
may want memory from other nodes before reclaim should be triggered.  (If
the caller wants reclaim then he can directly use __GFP_THISNODE instead).

There is no flag to avoid reclaim in the page allocator and adding yet
another GFP_xx flag would be difficult given that we are out of available
flags.

So just compare and see if all bits for GFP_THISNODE (__GFP_THISNODE,
__GFP_NORETRY and __GFP_NOWARN) are set.  If so then we return NULL before
waking up kswapd.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This addresses two issues:

1. Kmalloc_node() may intermittently return NULL if we are allocating
   from the current node and are unable to obtain memory for the current
   node from the page allocator.  This is because we call ___cache_alloc()
   if nodeid == numa_node_id() and ____cache_alloc is not able to fallback
   to other nodes.

   This was introduced in the 2.6.19 development cycle.  <= 2.6.18 in
   that case does not do a restricted allocation and blindly trusts the
   page allocator to have given us memory from the indicated node.  It
   inserts the page regardless of the node it came from into the queues for
   the current node.

2. If kmalloc_node() is used on a node that has not been bootstrapped
   yet then we may try to pass an invalid node number to
   ____cache_alloc_node() triggering a BUG().

   Change the function to call fallback_alloc() instead.  Only call
   fallback_alloc() if we are allowed to fallback at all.  The need to
   handle a node not bootstrapped yet also first surfaced in the 2.6.19
   cycle.

Update the comments since they were still describing the old kmalloc_node
from 2.6.12.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Cc: Christoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Replace all uses of kmem_cache_t with struct kmem_cache.

The patch was generated using the following script:

	#!/bin/sh
	#
	# Replace one string by another in all the kernel sources.
	#

	set -e

	for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do
		quilt add $file
		sed -e "1,\$s/$1/$2/g" $file >/tmp/$$
		mv /tmp/$$ $file
		quilt refresh
	done

The script was run like this

	sh replace kmem_cache_t "struct kmem_cache"
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

SLAB_DMA is an alias of GFP_DMA. This is the last one so we
remove the leftover comment too.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

SLAB_KERNEL is an alias of GFP_KERNEL.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

SLAB_ATOMIC is an alias of GFP_ATOMIC
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

SLAB_USER is an alias of GFP_USER
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

SLAB_NOFS is an alias of GFP_NOFS.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

SLAB_NOIO is an alias of GFP_NOIO with a single instance of use.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

SLAB_LEVEL_MASK is only used internally to the slab and is
and alias of GFP_LEVEL_MASK.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

It is only used internally in the slab.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

David Binderman and his Intel C compiler rightly observe that
install_file_pte no longer has any use for its pte_val.
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Cc: d binderman <dcb314@hotmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

These patches introduced new switch statements which are indented contrary
to the concensus in mm/*.c.  Fix them up to match that concensus.

    [PATCH] node local per-cpu-pages
    [PATCH] ZVC: Scale thresholds depending on the size of the system
    commit e7c8d5c9
    commit df9ecabaSigned-off-by: NAndy Whitcroft <apw@shadowen.org>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The fsfuzzer found this; with a corrupt small swapfile that claims to have
many pages:

  [root]# file swap.741.img
  swap.741.img: Linux/i386 swap file (new style) 1 (4K pages) size 1040191487 pages
  [root]# ls -l swap.741.img
  -rw-r--r-- 1 root root 16777216 Nov 22 05:18 swap.741.img

sys_swapon() will try to vmalloc all those pages, and -then- check to see if
the file is actually that large:

                if (!(p->swap_map = vmalloc(maxpages * sizeof(short)))) {
  <snip>
        if (swapfilesize && maxpages > swapfilesize) {
                printk(KERN_WARNING
                       "Swap area shorter than signature indicates\n");

It seems to me that it would make more sense to move this test up before
the vmalloc, with the other checks, to avoid the OOM-killer in this
situation...
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

x86 NUMA systems only define bootmem for node 0.  alloc_bootmem_node() and
friends therefore ignore the passed pgdat and use NODE_DATA(0) in all
cases.  This leads to the following warnings as we are not using the passed
parameter:

  .../mm/page_alloc.c: In function 'zone_wait_table_init':
  .../mm/page_alloc.c:2259: warning: unused variable 'pgdat'

One option would be to define all variables used with these macros
__attribute__ ((unused)), but this would leave us exposed should these
become genuinely unused.

The key here is that we _are_ using the value, we ignore it but that is a
deliberate action.  This patch adds a nested local variable within the
alloc_bootmem_node helper to which the pgdat parameter is assigned making
it 'used'.  The nested local is marked __attribute__ ((unused)) to silence
this same warning for it.
Signed-off-by: NAndy Whitcroft <apw@shadowen.org>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

NUMA node ids are passed as either int or unsigned int almost exclusivly
page_to_nid and zone_to_nid both return unsigned long.  This is a throw
back to when page_to_nid was a #define and was thus exposing the real type
of the page flags field.

In addition to fixing up the definitions of page_to_nid and zone_to_nid I
audited the users of these functions identifying the following incorrect
uses:

1) mm/page_alloc.c show_node() -- printk dumping the node id,
2) include/asm-ia64/pgalloc.h pgtable_quicklist_free() -- comparison
   against numa_node_id() which returns an int from cpu_to_node(), and
3) mm/mpolicy.c check_pte_range -- used as an index in node_isset which
   uses bit_set which in generic code takes an int.
Signed-off-by: NAndy Whitcroft <apw@shadowen.org>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

drain_node_pages() currently drains the complete pageset of all pages.  If
there are a large number of pages in the queues then we may hold off
interrupts for too long.

Duplicate the method used in free_hot_cold_page.  Only drain pcp->batch
pages at one time.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Remove all uses of kmem_cache_t (the most were left in slab.h).  The
typedef for kmem_cache_t is then only necessary for other kernel
subsystems.  Add a comment to that effect.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The names_cachep is used for getname() and putname().  So lets put it into
fs.h near those two definitions.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

fs_cachep is only used in kernel/exit.c and in kernel/fork.c.

It is used to store fs_struct items so it should be placed in linux/fs_struct.h
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

filp_cachep is only used in fs/file_table.c and in fs/dcache.c where
it is defined.

Move it to related definitions in linux/file.h.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Proper place is in file.h since files_cachep uses are rated to file I/O.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

vm_area_cachep is used to store vm_area_structs. So move to mm.h.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Move sighand_cachep definitioni to linux/signal.h

The sighand cache is only used in fs/exec.c and kernel/fork.c.  It is defined
in kernel/fork.c but only used in fs/exec.c.

The sighand_cachep is related to signal processing.  So add the definition to
signal.h.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Remove bio_cachep from slab.h - it no longer exists.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch makes the needlessly global "global_faults" static.
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

When booting a NUMA system with nodes that have no memory (eg by limiting
memory), bootmem_alloc_core tried to find pages in an uninitialized
bootmem_map.  This caused a null pointer access.  This fix adds a check, so
that NULL is returned.  That will enable the caller (bootmem_alloc_nopanic)
to alloc memory on other without a panic.
Signed-off-by: NChristian Krafft <krafft@de.ibm.com>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Martin Bligh <mbligh@google.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The patch (as824b) makes percpu_free() ignore NULL arguments, as one would
expect for a deallocation routine.  (Note that free_percpu is #defined as
percpu_free in include/linux/percpu.h.) A few callers are updated to remove
now-unneeded tests for NULL.  A few other callers already seem to assume
that passing a NULL pointer to percpu_free() is okay!

The patch also removes an unnecessary NULL check in percpu_depopulate().
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Node-aware allocation of skbs for the receive path.

Details:

  - __alloc_skb gets a new node argument and cals the node-aware
    slab functions with it.
  - netdev_alloc_skb passed the node number it gets from dev_to_node
    to it, everyone else passes -1 (any node)
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

For node-aware skb allocations we need information about the node in struct
net_device or struct device.  Davem suggested to put it into struct device
which this patch does.

In particular:

 - struct device gets a new int numa_node member if CONFIG_NUMA is set
 - there are two new helpers, dev_to_node and set_dev_node to
   transparently deal with the non-numa case
 - for pci devices the node-info is set to the value we get from
   pcibus_to_node.

Note that for some architectures pcibus_to_node doesn't work yet at the time
we call it currently.  This is harmless and will just mean skb allocations
aren't node-local on this architectures until the implementation of
pcibus_to_node on these architectures have been updated (There are patches for
x86 and x86_64 floating around)

[akpm@osdl.org: cleanup]
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

We have variants of kmalloc and kmem_cache_alloc that leave leak tracking to
the caller.  This is used for subsystem-specific allocators like skb_alloc.

To make skb_alloc node-aware we need similar routines for the node-aware slab
allocator, which this patch adds.

Note that the code is rather ugly, but it mirrors the non-node-aware code 1:1:

[akpm@osdl.org: add module export]
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

It would be possible for /proc/swaps to not always print out the header:

swapon /dev/hdc2
swapon /dev/hde2
swapoff /dev/hdc2

At this point /proc/swaps would not have a header.
Signed-off-by: NSuleiman Souhlal <suleiman@google.com>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

OOM can panic due to the processes stuck in __alloc_pages() doing infinite
rebalance loop while no memory can be reclaimed.  OOM killer tries to kill
some processes, but unfortunetaly, rebalance label was moved by someone
below the TIF_MEMDIE check, so buddy allocator doesn't see that process is
OOM-killed and it can simply fail the allocation :/

Observed in reality on RHEL4(2.6.9)+OpenVZ kernel when a user doing some
memory allocation tricks triggered OOM panic.
Signed-off-by: NDenis Lunev <den@sw.ru>
Signed-off-by: NKirill Korotaev <dev@openvz.org>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

mm is defined as vma->vm_mm, so use that.
Acked-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Currently a user process cannot rise its own oom_adj value (i.e.
unprotecting itself from the OOM killer).  As this value is stored in the
task structure it gets inherited and the unprivileged childs will be unable
to rise it.

The EPERM will be handled by the generic proc fs layer, as only processes
with the proper caps or the owner of the process will be able to write to
the file.  So we allow only the processes with CAP_SYS_RESOURCE to lower
the value, otherwise it will get an EACCES which seems more appropriate
than EPERM.
Signed-off-by: NGuillem Jover <guillem.jover@nokia.com>
Acked-by: NAndrea Arcangeli <andrea@novell.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

kunmap_atomic() will call kpte_clear_flush with vaddr/ptep arguments which
don't correspond if the vaddr is just a normal lowmem address (ie, not in
the KMAP area).  This patch makes sure that the pte is only cleared if kmap
area was actually used for the mapping.
Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: Zachary Amsden <zach@vmware.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Make kmap_atomic/kunmap_atomic denote a pagefault disabled scope.  All non
trivial implementations already do this anyway.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: NNick Piggin <npiggin@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>