Commit Graph

4147 Commits (5303b68f57c227c27193a14e57dd12be27cd670f)

Author SHA1 Message Date
Yinghai Lu 5303b68f57 memblock: Add memblock_find_in_range()
This is a wrapper for memblock_find_base() using slightly different
arguments (start,end instead of start,size for example) in order to
make it easier to convert existing arch/x86 code.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:34 +10:00
Yinghai Lu 10d0643988 memblock: Option for the architecture to put memblock into the .init section
Arch code can define ARCH_DISCARD_MEMBLOCK in asm/memblock.h,
which in turns causes memblock code and data to go respectively
into the .init and .initdata sections. This will be used by the
x86 architecture.

If ARCH_DISCARD_MEMBLOCK is defined, the debugfs files to inspect
the memblock arrays after boot are not created.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:33 +10:00
Benjamin Herrenschmidt 25818f0f28 memblock: Make MEMBLOCK_ERROR be 0
And ensure we don't hand out 0 as a valid allocation. We put the
low limit at PAGE_SIZE arbitrarily.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:30 +10:00
Yinghai Lu 37d8d4bf48 memblock: Export MEMBLOCK_ERROR
will used by x86 memblock_x86_find_in_range_node and nobootmem replacement

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:29 +10:00
Yinghai Lu ea9e4376bb memblock: Improve debug output when resizing the reserve array
Print out the location info in addition to which array is being
resized. Also use memblocK_dbg() to put that under control of
the memblock_debug flag.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:28 +10:00
Yinghai Lu 5e63cf43af memblock: Expose some memblock bits for use by x86
This exposes memblock_debug and associated memblock_dbg() macro,
along with memblock_can_resize so that x86 can use these when
ported to use memblock

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:27 +10:00
Benjamin Herrenschmidt 6d03b885f0 memblock: Add debugfs files to dump the arrays content
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:26 +10:00
Benjamin Herrenschmidt 918fe8d603 memblock: Make memblock_alloc_try_nid() fallback to MEMBLOCK_ALLOC_ANYWHERE
memblock_alloc_nid() used to fallback to allocating anywhere by using
memblock_alloc() as a fallback.

However, some of my previous patches limit memblock_alloc() to the region
covered by MEMBLOCK_ALLOC_ACCESSIBLE which is not quite what we want
for memblock_alloc_try_nid().

So we fix it by explicitely using MEMBLOCK_ALLOC_ANYWHERE.

Not that so far only sparc uses memblock_alloc_nid() and it hasn't been updated
to clamp the accessible zone yet. Thus the temporary "breakage" should have
no effect.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:25 +10:00
Benjamin Herrenschmidt 9d1e24928e memblock: Separate memblock_alloc_nid() and memblock_alloc_try_nid()
The former is now strict, it will fail if it cannot honor the allocation
within the node, while the later implements the previous semantic which
falls back to allocating anywhere.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:24 +10:00
Benjamin Herrenschmidt c196f76fd5 memblock: NUMA allocate can now use early_pfn_map
We now provide a default (weak) implementation of memblock_nid_range()
which uses the early_pfn_map[] if CONFIG_ARCH_POPULATES_NODE_MAP
is set. Sparc still needs to use its own method due to the way
the pages can be scattered between nodes.

This implementation is inefficient due to our main algorithm and
callback construct wanting to work on an ascending addresses bases
while early_pfn_map[] would rather work with nid's (it's unsorted
at that stage). But it should work and we can look into improving
it subsequently, possibly using arch compile options to chose a
different algorithm alltogether.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:23 +10:00
Benjamin Herrenschmidt fef501d49d memblock: Add "start" argument to memblock_find_base()
To constraint the search of a region between two boundaries,
which will be used by the new NUMA aware allocator among others.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:22 +10:00
Benjamin Herrenschmidt d2cd563ba8 memblock: Add arch function to control coalescing of memblock memory regions
Some archs such as ARM want to avoid coalescing accross things such
as the lowmem/highmem boundary or similar. This provides the option
to control it via an arch callback for which a weak default is provided
which always allows coalescing.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:21 +10:00
Benjamin Herrenschmidt 142b45a72e memblock: Add array resizing support
When one of the array gets full, we resize it. After much thinking and
a few iterations of that code, I went back to on-demand resizing using
the (new) internal memblock_find_base() function, which is pretty much what
Yinghai initially proposed, though there some differences in the details.

To work this relies on the default alloc limit being set sensibly by
the architecture.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:20 +10:00
Benjamin Herrenschmidt 6ed311b282 memblock: Move functions around into a more sensible order
Some shuffling is needed for doing array resize so we may as well
put some sense into the ordering of the functions in the whole memblock.c
file. No code change. Added some comments.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:19 +10:00
Benjamin Herrenschmidt 7f219c736f memblock: split memblock_find_base() out of __memblock_alloc_base()
This will be used by the array resize code and might prove useful
to some arch code as well at which point it can be made non-static.

Also add comment as to why aligning size is important

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---

v2. Fix loss of size alignment
v3. Fix result code
2010-08-05 12:56:18 +10:00
Benjamin Herrenschmidt 7590abe891 memblock: Move memblock_init() to the bottom of the file
It's a real PITA to have to search for it in the middle

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:17 +10:00
Benjamin Herrenschmidt 4d629f9a02 memblock: Define MEMBLOCK_ERROR internally instead of using ~(phys_addr_t)0
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:16 +10:00
Benjamin Herrenschmidt 3a9c2c81eb memblock: Make memblock_find_region() out of memblock_alloc_region()
This function will be used to locate a free area to put the new memblock
arrays when attempting to resize them. memblock_alloc_region() is gone,
the two callsites now call memblock_add_region().

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
v2. Fix membase_alloc_nid_region() conversion
2010-08-05 12:56:14 +10:00
Benjamin Herrenschmidt 449e8df39d memblock: Add debug markers at the end of the array
Since we allocate one more than needed, why not do a bit of sanity checking
here to ensure we don't walk past the end of the array ?

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:13 +10:00
Benjamin Herrenschmidt bf23c51f1f memblock: Move memblock arrays to static storage in memblock.c and make their size a variable
This is in preparation for having resizable arrays.

Note that we still allocate one more than needed, this is unchanged from
the previous implementation.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:12 +10:00
Benjamin Herrenschmidt 4734b594c6 memblock: Remove memblock_type.size and add memblock.memory_size instead
Right now, both the "memory" and "reserved" memblock_type structures have
a "size" member. It represents the calculated memory size in the former
case and is unused in the latter.

This moves it out to the main memblock structure instead

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:11 +10:00
Benjamin Herrenschmidt 2898cc4cdf memblock: Change u64 to phys_addr_t
Let's not waste space and cycles on archs that don't support >32-bit
physical address space.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:09 +10:00
Benjamin Herrenschmidt cd3db0c4ca memblock: Remove rmo_size, burry it in arch/powerpc where it belongs
The RMA (RMO is a misnomer) is a concept specific to ppc64 (in fact
server ppc64 though I hijack it on embedded ppc64 for similar purposes)
and represents the area of memory that can be accessed in real mode
(aka with MMU off), or on embedded, from the exception vectors (which
is bolted in the TLB) which pretty much boils down to the same thing.

We take that out of the generic MEMBLOCK data structure and move it into
arch/powerpc where it belongs, renaming it to "RMA" while at it.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:08 +10:00
Benjamin Herrenschmidt e63075a3c9 memblock: Introduce default allocation limit and use it to replace explicit ones
This introduce memblock.current_limit which is used to limit allocations
from memblock_alloc() or memblock_alloc_base(..., MEMBLOCK_ALLOC_ACCESSIBLE).

The old MEMBLOCK_ALLOC_ANYWHERE changes value from 0 to ~(u64)0 and can still
be used with memblock_alloc_base() to allocate really anywhere.

It is -no-longer- cropped to MEMBLOCK_REAL_LIMIT which disappears.

Note to archs: I'm leaving the default limit to MEMBLOCK_ALLOC_ANYWHERE. I
strongly recommend that you ensure that you set an appropriate limit
during boot in order to guarantee that an memblock_alloc() at any time
results in something that is accessible with a simple __va().

The reason is that a subsequent patch will introduce the ability for
the array to resize itself by reallocating itself. The MEMBLOCK core will
honor the current limit when performing those allocations.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:07 +10:00
Benjamin Herrenschmidt 27f574c223 memblock: Expose MEMBLOCK_ALLOC_ANYWHERE
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:06 +10:00
Benjamin Herrenschmidt c3f72b5706 memblock: Factor the lowest level alloc function
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:05 +10:00
Benjamin Herrenschmidt 35a1f0bd07 memblock: Remove nid_range argument, arch provides memblock_nid_range() instead
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:04 +10:00
Benjamin Herrenschmidt b693fffb18 memblock: Remove memblock_find()
Nobody uses it anymore. It's semantics were ... weird

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:03 +10:00
Benjamin Herrenschmidt 72d4b0b4e0 memblock: Implement memblock_is_memory and memblock_is_region_memory
To make it fast, we steal ARM's binary search for memblock_is_memory()
and we use that to also the replace existing implementation of
memblock_is_reserved().

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-04 14:38:47 +10:00
Benjamin Herrenschmidt e3239ff92a memblock: Rename memblock_region to memblock_type and memblock_property to memblock_region
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-04 14:21:49 +10:00
Benjamin Herrenschmidt f1c2c19c49 memblock: Fix memblock_is_region_reserved() to return a boolean
All callers expect a boolean result which is true if the region
overlaps a reserved region. However, the implementation actually
returns -1 if there is no overlap, and a region index (0 based)
if there is.

Make it behave as callers (and common sense) expect.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-04 14:17:17 +10:00
Hugh Dickins de51257aa3 mm: fix ia64 crash when gcore reads gate area
Debian's ia64 autobuilders have been seeing kernel freeze or reboot
when running the gdb testsuite (Debian bug 588574): dannf bisected to
2.6.32 62eede62da "mm: ZERO_PAGE without
PTE_SPECIAL"; and reproduced it with gdb's gcore on a simple target.

I'd missed updating the gate_vma handling in __get_user_pages(): that
happens to use vm_normal_page() (nowadays failing on the zero page),
yet reported success even when it failed to get a page - boom when
access_process_vm() tried to copy that to its intermediate buffer.

Fix this, resisting cleanups: in particular, leave it for now reporting
success when not asked to get any pages - very probably safe to change,
but let's not risk it without testing exposure.

Why did ia64 crash with 16kB pages, but succeed with 64kB pages?
Because setup_gate() pads each 64kB of its gate area with zero pages.

Reported-by: Andreas Barth <aba@not.so.argh.org>
Bisected-by: dann frazier <dannf@debian.org>
Signed-off-by: Hugh Dickins <hughd@google.com>
Tested-by: dann frazier <dannf@dannf.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-07-30 18:56:09 -07:00
Yinghai Lu b8ab9f8202 x86,nobootmem: make alloc_bootmem_node fall back to other node when 32bit numa is used
Borislav Petkov reported his 32bit numa system has problem:

[    0.000000] Reserving total of 4c00 pages for numa KVA remap
[    0.000000] kva_start_pfn ~ 32800 max_low_pfn ~ 375fe
[    0.000000] max_pfn = 238000
[    0.000000] 8202MB HIGHMEM available.
[    0.000000] 885MB LOWMEM available.
[    0.000000]   mapped low ram: 0 - 375fe000
[    0.000000]   low ram: 0 - 375fe000
[    0.000000] alloc (nid=8 100000 - 7ee00000) (1000000 - ffffffff) 1000 1000 => 34e7000
[    0.000000] alloc (nid=8 100000 - 7ee00000) (1000000 - ffffffff) 200 40 => 34c9d80
[    0.000000] alloc (nid=0 100000 - 7ee00000) (1000000 - ffffffffffffffff) 180 40 => 34e6140
[    0.000000] alloc (nid=1 80000000 - c7e60000) (1000000 - ffffffffffffffff) 240 40 => 80000000
[    0.000000] BUG: unable to handle kernel paging request at 40000000
[    0.000000] IP: [<c2c8cff1>] __alloc_memory_core_early+0x147/0x1d6
[    0.000000] *pdpt = 0000000000000000 *pde = f000ff53f000ff00
...
[    0.000000] Call Trace:
[    0.000000]  [<c2c8b4f8>] ? __alloc_bootmem_node+0x216/0x22f
[    0.000000]  [<c2c90c9b>] ? sparse_early_usemaps_alloc_node+0x5a/0x10b
[    0.000000]  [<c2c9149e>] ? sparse_init+0x1dc/0x499
[    0.000000]  [<c2c79118>] ? paging_init+0x168/0x1df
[    0.000000]  [<c2c780ff>] ? native_pagetable_setup_start+0xef/0x1bb

looks like it allocates too much high address for bootmem.

Try to cut limit with get_max_mapped()

Reported-by: Borislav Petkov <borislav.petkov@amd.com>
Tested-by: Conny Seidel <conny.seidel@amd.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: <stable@kernel.org>		[2.6.34.x]
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-07-20 16:25:40 -07:00
Nick Piggin a6aa62a090 mm/vmscan.c: fix mapping use after free
We need lock_page_nosync() here because we have no reference to the
mapping when taking the page lock.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-07-20 16:25:40 -07:00
Dave Chinner 7f8275d0d6 mm: add context argument to shrinker callback
The current shrinker implementation requires the registered callback
to have global state to work from. This makes it difficult to shrink
caches that are not global (e.g. per-filesystem caches). Pass the shrinker
structure to the callback so that users can embed the shrinker structure
in the context the shrinker needs to operate on and get back to it in the
callback via container_of().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-07-19 14:56:17 +10:00
Linus Torvalds 46ac0cc92e Merge branch 'kmemleak' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-2.6-cm
* 'kmemleak' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-2.6-cm:
  kmemleak: Add support for NO_BOOTMEM configurations
  kmemleak: Annotate false positive in init_section_page_cgroup()
2010-07-19 13:18:34 -07:00
Catalin Marinas 9078370c0d kmemleak: Add support for NO_BOOTMEM configurations
With commits 08677214 and 59be5a8e, alloc_bootmem()/free_bootmem() and
friends use the early_res functions for memory management when
NO_BOOTMEM is enabled. This patch adds the kmemleak calls in the
corresponding code paths for bootmem allocations.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: stable@kernel.org
2010-07-19 11:54:15 +01:00
Catalin Marinas 7952f98818 kmemleak: Annotate false positive in init_section_page_cgroup()
The pointer to the page_cgroup table allocated in
init_section_page_cgroup() is stored in section->page_cgroup as (base -
pfn). Since this value does not point to the beginning or inside the
allocated memory block, kmemleak reports a false positive.

This was reported in bugzilla.kernel.org as #16297.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Adrien Dessemond <adrien.dessemond@gmail.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Andrew Morton <akpm@linux-foundation.org>
2010-07-19 11:54:14 +01:00
Yinghai Lu 95f72d1ed4 lmb: rename to memblock
via following scripts

      FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')

      sed -i \
        -e 's/lmb/memblock/g' \
        -e 's/LMB/MEMBLOCK/g' \
        $FILES

      for N in $(find . -name lmb.[ch]); do
        M=$(echo $N | sed 's/lmb/memblock/g')
        mv $N $M
      done

and remove some wrong change like lmbench and dlmb etc.

also move memblock.c from lib/ to mm/

Suggested-by: Ingo Molnar <mingo@elte.hu>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-14 17:14:00 +10:00
Linus Torvalds c77e9e6826 Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  writeback: simplify the write back thread queue
  writeback: split writeback_inodes_wb
  writeback: remove writeback_inodes_wbc
  fs-writeback: fix kernel-doc warnings
  splice: check f_mode for seekable file
  splice: direct_splice_actor() should not use pos in sd
2010-07-08 08:06:40 -07:00
Christoph Hellwig 83ba7b071f writeback: simplify the write back thread queue
First remove items from work_list as soon as we start working on them.  This
means we don't have to track any pending or visited state and can get
rid of all the RCU magic freeing the work items - we can simply free
them once the operation has finished.  Second use a real completion for
tracking synchronous requests - if the caller sets the completion pointer
we complete it, otherwise use it as a boolean indicator that we can free
the work item directly.  Third unify struct wb_writeback_args and struct
bdi_work into a single data structure, wb_writeback_work.  Previous we
set all parameters into a struct wb_writeback_args, copied it into
struct bdi_work, copied it again on the stack to use it there.  Instead
of just allocate one structure dynamically or on the stack and use it
all the way through the stack.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-07-06 08:59:53 +02:00
Christoph Hellwig 9c3a8ee8a1 writeback: remove writeback_inodes_wbc
This was just an odd wrapper around writeback_inodes_wb.  Removing this
also allows to get rid of the bdi member of struct writeback_control
which was rather out of place there.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-07-06 08:54:03 +02:00
Lee Schermerhorn 5c0c165490 mempolicy: fix dangling reference to tmpfs superblock mpol
My patch to "Factor out duplicate put/frees in mpol_shared_policy_init()
to a common return path"; and Dan Carpenter's fix thereto both left a
dangling reference to the incoming tmpfs superblock mempolicy structure.
A similar leak was introduced earlier when the nodemask was moved offstack
to the scratch area despite the note in the comment block regarding the
incoming ref.

Move the remaining 'put of the incoming "mpol" to the common exit path to
drop the reference.

Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Acked-by: Dan Carpenter <error27@gmail.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-06-29 15:29:31 -07:00
KAMEZAWA Hiroyuki 4d845ebf4c memcg: fix wake up in oom wait queue
OOM-waitqueue should be waken up when oom_disable is canceled.  This is a
fix for 3c11ecf448 ("memcg: oom kill disable and oom status").

How to test:
 Create a cgroup A...
 1. set memory.limit and memory.memsw.limit to be small value
 2. echo 1 > /cgroup/A/memory.oom_control, this disables oom-kill.
 3. run a program which must cause OOM.

A program executed in 3 will sleep by oom_waiqueue in memcg.  Then, how to
wake it up is problem.

 1. echo 0 > /cgroup/A/memory.oom_control (enable OOM-killer)
 2. echo big mem > /cgroup/A/memory.memsw.limit_in_bytes(allow more swap)

etc..

Without the patch, a task in slept can not be waken up.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-06-29 15:29:30 -07:00
Linus Torvalds 984bc9601f Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  block: Don't count_vm_events for discard bio in submit_bio.
  cfq: fix recursive call in cfq_blkiocg_update_completion_stats()
  cfq-iosched: Fixed boot warning with BLK_CGROUP=y and CFQ_GROUP_IOSCHED=n
  cfq: Don't allow queue merges for queues that have no process references
  block: fix DISCARD_BARRIER requests
  cciss: set SCSI max cmd len to 16, as default is wrong
  cpqarray: fix two more wrong section type
  cpqarray: fix wrong __init type on pci probe function
  drbd: Fixed a race between disk-attach and unexpected state changes
  writeback: fix pin_sb_for_writeback
  writeback: add missing requeue_io in writeback_inodes_wb
  writeback: simplify and split bdi_start_writeback
  writeback: simplify wakeup_flusher_threads
  writeback: fix writeback_inodes_wb from writeback_inodes_sb
  writeback: enforce s_umount locking in writeback_inodes_sb
  writeback: queue work on stack in writeback_inodes_sb
  writeback: fix writeback completion notifications
2010-06-29 10:42:52 -07:00
Tejun Heo 9983b6f0cf percpu: fix first chunk match in per_cpu_ptr_to_phys()
per_cpu_ptr_to_phys() determines whether the passed in @addr belongs
to the first_chunk or not by just matching the address against the
address range of the base unit (unit0, used by cpu0).  When an adress
from another cpu was passed in, it will always determine that the
address doesn't belong to the first chunk even when it does.  This
makes the function return a bogus physical address which may lead to
crash.

This problem was discovered by Cliff Wickman while investigating a
crash during kdump on a SGI UV system.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Cliff Wickman <cpw@sgi.com>
Tested-by: Cliff Wickman <cpw@sgi.com>
Cc: stable@kernel.org
2010-06-18 15:07:23 +02:00
Pavel V. Panteleev a92d3ff9e5 percpu: fix trivial bugs in pcpu_build_alloc_info()
Fix the following two trivial bugs in pcpu_build_alloc_info()

* we should memset group_cnt to 0 by size of group_cnt, not size of
  group_map (both are of the same size, so the bug isn't dangerous)

* we can delete useless variable group_cnt_max.

Signed-off-by: Pavel V. Panteleev <pp_84@mail.ru>
Signed-off-by: Tejun Heo <tj@kernel.org>
2010-06-17 10:07:25 +02:00
Christoph Hellwig c5444198ca writeback: simplify and split bdi_start_writeback
bdi_start_writeback now never gets a superblock passed, so we can just remove
that case.  And to further untangle the code and flatten the call stack
split it into two trivial helpers for it's two callers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-06-11 12:58:08 +02:00
Dave Chinner d87815cb20 writeback: limit write_cache_pages integrity scanning to current EOF
sync can currently take a really long time if a concurrent writer is
extending a file. The problem is that the dirty pages on the address
space grow in the same direction as write_cache_pages scans, so if
the writer keeps ahead of writeback, the writeback will not
terminate until the writer stops adding dirty pages.

For a data integrity sync, we only need to write the pages dirty at
the time we start the writeback, so we can stop scanning once we get
to the page that was at the end of the file at the time the scan
started.

This will prevent operations like copying a large file preventing
sync from completing as it will not write back pages that were
dirtied after the sync was started. This does not impact the
existing integrity guarantees, as any dirty page (old or new)
within the EOF range at the start of the scan will still be
captured.

This patch will not prevent sync from blocking on large writes into
holes. That requires more complex intervention while this patch only
addresses the common append-case of this sync holdoff.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-06-08 18:12:44 -07:00
Dave Chinner 0b5649278e writeback: pay attention to wbc->nr_to_write in write_cache_pages
If a filesystem writes more than one page in ->writepage, write_cache_pages
fails to notice this and continues to attempt writeback when wbc->nr_to_write
has gone negative - this trace was captured from XFS:

    wbc_writeback_start: towrt=1024
    wbc_writepage: towrt=1024
    wbc_writepage: towrt=0
    wbc_writepage: towrt=-1
    wbc_writepage: towrt=-5
    wbc_writepage: towrt=-21
    wbc_writepage: towrt=-85

This has adverse effects on filesystem writeback behaviour. write_cache_pages()
needs to terminate after a certain number of pages are written, not after a
certain number of calls to ->writepage are made.  This is a regression
introduced by 17bc6c30cf ("vfs: Add
no_nrwrite_index_update writeback control flag"), but cannot be reverted
directly due to subsequent bug fixes that have gone in on top of it.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-06-08 18:12:44 -07:00