27 Sep, 2006
11 commits
-
The NUMA_BUILD constant is always available and will be set to 1 on
NUMA_BUILDs. That way checks valid only under CONFIG_NUMA can easily be done
without #ifdef CONFIG_NUMAF.e.
if (NUMA_BUILD && ) {
...
}[akpm: not a thing we'd normally do, but CONFIG_NUMA is special: it is
causing ifdef explosion in core kernel, so let's see if this is a comfortable
way in whcih to control that]Signed-off-by: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
On larger systems, the amount of output dumped on the console when you do
SysRq-M is beyond insane. This patch is trying to reduce it somewhat as
even with the smaller NUMA systems that have hit the desktop this seems to
be a fair thing to do.The philosophy I have taken is as follows:
1) If a zone is empty, don't tell, we don't need yet another line
telling us so. The information is available since one can look up
the fact how many zones were initialized in the first place.
2) Put as much information on a line is possible, if it can be done
in one line, rahter than two, then do it in one. I tried to format
the temperature stuff for easy reading.Change show_free_areas() to not print lines for empty zones. If no zone
output is printed, the zone is empty. This reduces the number of lines
dumped to the console in sysrq on a large system by several thousand lines.Change the zone temperature printouts to use one line per CPU instead of
two lines (one hot, one cold). On a 1024 CPU, 1024 node system, this
reduces the console output by over a million lines of output.While this is a bigger problem on large NUMA systems, it is also applicable
to smaller desktop sized and mid range NUMA systems.Old format:
Mem-info:
Node 0 DMA per-cpu:
cpu 0 hot: high 42, batch 7 used:24
cpu 0 cold: high 14, batch 3 used:1
cpu 1 hot: high 42, batch 7 used:34
cpu 1 cold: high 14, batch 3 used:0
cpu 2 hot: high 42, batch 7 used:0
cpu 2 cold: high 14, batch 3 used:0
cpu 3 hot: high 42, batch 7 used:0
cpu 3 cold: high 14, batch 3 used:0
cpu 4 hot: high 42, batch 7 used:0
cpu 4 cold: high 14, batch 3 used:0
cpu 5 hot: high 42, batch 7 used:0
cpu 5 cold: high 14, batch 3 used:0
cpu 6 hot: high 42, batch 7 used:0
cpu 6 cold: high 14, batch 3 used:0
cpu 7 hot: high 42, batch 7 used:0
cpu 7 cold: high 14, batch 3 used:0
Node 0 DMA32 per-cpu: empty
Node 0 Normal per-cpu: empty
Node 0 HighMem per-cpu: empty
Node 1 DMA per-cpu:
[snip]
Free pages: 5410688kB (0kB HighMem)
Active:9536 inactive:4261 dirty:6 writeback:0 unstable:0 free:338168 slab:1931 mapped:1900 pagetables:208
Node 0 DMA free:1676304kB min:3264kB low:4080kB high:4896kB active:128048kB inactive:61568kB present:1970880kB pages_scanned:0 all_unreclaimable? no
lowmem_reserve[]: 0 0 0 0
Node 0 DMA32 free:0kB min:0kB low:0kB high:0kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no
lowmem_reserve[]: 0 0 0 0
Node 0 Normal free:0kB min:0kB low:0kB high:0kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no
lowmem_reserve[]: 0 0 0 0
Node 0 HighMem free:0kB min:512kB low:512kB high:512kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no
lowmem_reserve[]: 0 0 0 0
Node 1 DMA free:1951728kB min:3280kB low:4096kB high:4912kB active:5632kB inactive:1504kB present:1982464kB pages_scanned:0 all_unreclaimable? no
lowmem_reserve[]: 0 0 0 0
....New format:
Mem-info:
Node 0 DMA per-cpu:
CPU 0: Hot: hi: 42, btch: 7 usd: 41 Cold: hi: 14, btch: 3 usd: 2
CPU 1: Hot: hi: 42, btch: 7 usd: 40 Cold: hi: 14, btch: 3 usd: 1
CPU 2: Hot: hi: 42, btch: 7 usd: 0 Cold: hi: 14, btch: 3 usd: 0
CPU 3: Hot: hi: 42, btch: 7 usd: 0 Cold: hi: 14, btch: 3 usd: 0
CPU 4: Hot: hi: 42, btch: 7 usd: 0 Cold: hi: 14, btch: 3 usd: 0
CPU 5: Hot: hi: 42, btch: 7 usd: 0 Cold: hi: 14, btch: 3 usd: 0
CPU 6: Hot: hi: 42, btch: 7 usd: 0 Cold: hi: 14, btch: 3 usd: 0
CPU 7: Hot: hi: 42, btch: 7 usd: 0 Cold: hi: 14, btch: 3 usd: 0
Node 1 DMA per-cpu:
[snip]
Free pages: 5411088kB (0kB HighMem)
Active:9558 inactive:4233 dirty:6 writeback:0 unstable:0 free:338193 slab:1942 mapped:1918 pagetables:208
Node 0 DMA free:1677648kB min:3264kB low:4080kB high:4896kB active:129296kB inactive:58864kB present:1970880kB pages_scanned:0 all_unreclaimable? no
lowmem_reserve[]: 0 0 0 0
Node 1 DMA free:1948448kB min:3280kB low:4096kB high:4912kB active:6864kB inactive:3536kB present:1982464kB pages_scanned:0 all_unreclaimable? no
lowmem_reserve[]: 0 0 0 0Signed-off-by: Jes Sorensen
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
kmalloc_node() falls back to ___cache_alloc() under certain conditions and
at that point memory policies may be applied redirecting the allocation
away from the current node. Therefore kmalloc_node(...,numa_node_id()) or
kmalloc_node(...,-1) may not return memory from the local node.Fix this by doing the policy check in __cache_alloc() instead of
____cache_alloc().This version here is a cleanup of Kiran's patch.
- Tested on ia64.
- Extra material removed.
- Consolidate the exit path if alternate_node_alloc() returned an object.[akpm@osdl.org: warning fix]
Signed-off-by: Alok N Kataria
Signed-off-by: Ravikiran Thirumalai
Signed-off-by: Shai Fultheim
Signed-off-by: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Clean up the invalidate code, and use a common function to safely remove
the page from pagecache.Signed-off-by: Nick Piggin
Cc: Hugh Dickins
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The VM is supposed to minimise the number of pages which get written off the
LRU (for IO scheduling efficiency, and for high reclaim-success rates). But
we don't actually have a clear way of showing how true this is.So add `nr_vmscan_write' to /proc/vmstat and /proc/zoneinfo - the number of
pages which have been written by the vm scanner in this zone and globally.Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Arch-independent zone-sizing determines the size of a node
(pgdat->node_spanned_pages) based on the physical memory that was
registered by the architecture. However, when
CONFIG_MEMORY_HOTPLUG_RESERVE is set, the architecture expects that the
spanned_pages will be much larger and that mem_map will be allocated that
is used lated on memory hot-add.This patch allows an architecture that sets CONFIG_MEMORY_HOTPLUG_RESERVE
to call push_node_boundaries() which will set the node beginning and end to
at *least* the requested boundary.Cc: Dave Hansen
Cc: Andy Whitcroft
Cc: Andi Kleen
Cc: Benjamin Herrenschmidt
Cc: Paul Mackerras
Cc: "Keith Mannthey"
Cc: "Luck, Tony"
Cc: KAMEZAWA Hiroyuki
Cc: Yasunori Goto
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
absent_pages_in_range() made the assumption that users of the API would not
care about holes beyound the end of physical memory. This was not the
case. This patch will account for ranges outside of physical memory as
holes correctly.Cc: Dave Hansen
Cc: Andy Whitcroft
Cc: Andi Kleen
Cc: Benjamin Herrenschmidt
Cc: Paul Mackerras
Cc: "Keith Mannthey"
Cc: "Luck, Tony"
Cc: KAMEZAWA Hiroyuki
Cc: Yasunori Goto
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The x86_64 code accounted for memmap and some portions of the the DMA zone as
holes. This was because those areas would never be reclaimed and accounting
for them as memory affects min watermarks. This patch will account for the
memmap as a memory hole. Architectures may optionally use set_dma_reserve()
if they wish to account for a portion of memory in ZONE_DMA as a hole.Signed-off-by: Mel Gorman
Cc: Dave Hansen
Cc: Andy Whitcroft
Cc: Andi Kleen
Cc: Benjamin Herrenschmidt
Cc: Paul Mackerras
Cc: "Keith Mannthey"
Cc: "Luck, Tony"
Cc: KAMEZAWA Hiroyuki
Cc: Yasunori Goto
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
At a basic level, architectures define structures to record where active
ranges of page frames are located. Once located, the code to calculate zone
sizes and holes in each architecture is very similar. Some of this zone and
hole sizing code is difficult to read for no good reason. This set of patches
eliminates the similar-looking architecture-specific code.The patches introduce a mechanism where architectures register where the
active ranges of page frames are with add_active_range(). When all areas have
been discovered, free_area_init_nodes() is called to initialise the pgdat and
zones. The zone sizes and holes are then calculated in an architecture
independent manner.Patch 1 introduces the mechanism for registering and initialising PFN ranges
Patch 2 changes ppc to use the mechanism - 139 arch-specific LOC removed
Patch 3 changes x86 to use the mechanism - 136 arch-specific LOC removed
Patch 4 changes x86_64 to use the mechanism - 74 arch-specific LOC removed
Patch 5 changes ia64 to use the mechanism - 52 arch-specific LOC removed
Patch 6 accounts for mem_map as a memory hole as the pages are not reclaimable.
It adjusts the watermarks slightlyTony Luck has successfully tested for ia64 on Itanium with tiger_defconfig,
gensparse_defconfig and defconfig. Bob Picco has also tested and debugged on
IA64. Jack Steiner successfully boot tested on a mammoth SGI IA64-based
machine. These were on patches against 2.6.17-rc1 and release 3 of these
patches but there have been no ia64-changes since release 3.There are differences in the zone sizes for x86_64 as the arch-specific code
for x86_64 accounts the kernel image and the starting mem_maps as memory holes
but the architecture-independent code accounts the memory as present.The big benefit of this set of patches is a sizable reduction of
architecture-specific code, some of which is very hairy. There should be a
greater reduction when other architectures use the same mechanisms for zone
and hole sizing but I lack the hardware to test on.Additional credit;
Dave Hansen for the initial suggestion and comments on early patches
Andy Whitcroft for reviewing early versions and catching numerous
errors
Tony Luck for testing and debugging on IA64
Bob Picco for fixing bugs related to pfn registration, reviewing a
number of patch revisions, providing a number of suggestions
on future direction and testing heavily
Jack Steiner and Robin Holt for testing on IA64 and clarifying
issues related to memory holes
Yasunori for testing on IA64
Andi Kleen for reviewing and feeding back about x86_64
Christian Kujau for providing valuable information related to ACPI
problems on x86_64 and testing potential fixesThis patch:
Define the structure to represent an active range of page frames within a node
in an architecture independent manner. Architectures are expected to register
active ranges of PFNs using add_active_range(nid, start_pfn, end_pfn) and call
free_area_init_nodes() passing the PFNs of the end of each zone.Signed-off-by: Mel Gorman
Signed-off-by: Bob Picco
Cc: Dave Hansen
Cc: Andy Whitcroft
Cc: Andi Kleen
Cc: Benjamin Herrenschmidt
Cc: Paul Mackerras
Cc: "Keith Mannthey"
Cc: "Luck, Tony"
Cc: KAMEZAWA Hiroyuki
Cc: Yasunori Goto
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
un-, de-, -free, -destroy, -exit, etc functions should in general return
void. Also,There is very little, say, filesystem driver code can do upon failed
kmem_cache_destroy(). If it will be decided to BUG in this case, BUG
should be put in generic code, instead.Signed-off-by: Alexey Dobriyan
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
* Rougly half of callers already do it by not checking return value
* Code in drivers/acpi/osl.c does the following to be sure:(void)kmem_cache_destroy(cache);
* Those who check it printk something, however, slab_error already printed
the name of failed cache.
* XFS BUGs on failed kmem_cache_destroy which is not the decision
low-level filesystem driver should make. Converted to ignore.Signed-off-by: Alexey Dobriyan
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
26 Sep, 2006
29 commits
-
Clean up mm/page_alloc.c#mark_free_pages() and make it avoid clearing
PageNosaveFree for PageNosave pages. This allows us to get rid of an ugly
hack in kernel/power/snapshot.c#copy_data_pages().Additionally, the page-copying loop in copy_data_pages() is moved to an
inline function.Signed-off-by: Rafael J. Wysocki
Cc: Pavel Machek
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Implement async reads for swsusp resuming.
Crufty old PIII testbox:
15.7 MB/s -> 20.3 MB/sSony Vaio:
14.6 MB/s -> 33.3 MB/sI didn't implement the post-resume bio_set_pages_dirty(). I don't really
understand why resume needs to run set_page_dirty() against these pages.It might be a worry that this code modifies PG_Uptodate, PG_Error and
PG_Locked against the image pages. Can this possibly affect the resumed-into
kernel? Hopefully not, if we're atomically restoring its mem_map?Cc: Pavel Machek
Cc: "Rafael J. Wysocki"
Cc: Jens Axboe
Cc: Laurent Riffard
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Switch the swsusp writeout code from 4k-at-a-time to 4MB-at-a-time.
Crufty old PIII testbox:
12.9 MB/s -> 20.9 MB/sSony Vaio:
14.7 MB/s -> 26.5 MB/sThe implementation is crude. A better one would use larger BIOs, but wouldn't
gain any performance.The memcpys will be mostly pipelined with the IO and basically come for free.
The ENOMEM path has not been tested. It should be.
Cc: Pavel Machek
Cc: "Rafael J. Wysocki"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
There are many places where we need to determine the node of a zone.
Currently we use a difficult to read sequence of pointer dereferencing.
Put that into an inline function and use throughout VM. Maybe we can find
a way to optimize the lookup in the future.Signed-off-by: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
I found two location in hugetlb.c where we chase pointer instead of using
page_to_nid(). Page_to_nid is more effective and can get the node directly
from page flags.Signed-off-by: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Update the comments for __oom_kill_task() to reflect the code changes.
Signed-off-by: Ram Gupta
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Minor performance fix.
If we reclaimed enough slab pages from a zone then we can avoid going off
node with the current allocation. Take care of updating nr_reclaimed when
reclaiming from the slab.Signed-off-by: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Currently one can enable slab reclaim by setting an explicit option in
/proc/sys/vm/zone_reclaim_mode. Slab reclaim is then used as a final
option if the freeing of unmapped file backed pages is not enough to free
enough pages to allow a local allocation.However, that means that the slab can grow excessively and that most memory
of a node may be used by slabs. We have had a case where a machine with
46GB of memory was using 40-42GB for slab. Zone reclaim was effective in
dealing with pagecache pages. However, slab reclaim was only done during
global reclaim (which is a bit rare on NUMA systems).This patch implements slab reclaim during zone reclaim. Zone reclaim
occurs if there is a danger of an off node allocation. At that point we1. Shrink the per node page cache if the number of pagecache
pages is more than min_unmapped_ratio percent of pages in a zone.2. Shrink the slab cache if the number of the nodes reclaimable slab pages
(patch depends on earlier one that implements that counter)
are more than min_slab_ratio (a new /proc/sys/vm tunable).The shrinking of the slab cache is a bit problematic since it is not node
specific. So we simply calculate what point in the slab we want to reach
(current per node slab use minus the number of pages that neeed to be
allocated) and then repeately run the global reclaim until that is
unsuccessful or we have reached the limit. I hope we will have zone based
slab reclaim at some point which will make that easier.The default for the min_slab_ratio is 5%
Also remove the slab option from /proc/sys/vm/zone_reclaim_mode.
[akpm@osdl.org: cleanups]
Signed-off-by: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Remove the atomic counter for slab_reclaim_pages and replace the counter
and NR_SLAB with two ZVC counter that account for unreclaimable and
reclaimable slab pages: NR_SLAB_RECLAIMABLE and NR_SLAB_UNRECLAIMABLE.Change the check in vmscan.c to refer to to NR_SLAB_RECLAIMABLE. The
intend seems to be to check for slab pages that could be freed.Signed-off-by: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
*_pages is a better description of the role of the variable.
Signed-off-by: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The allocpercpu functions __alloc_percpu and __free_percpu() are heavily
using the slab allocator. However, they are conceptually slab. This also
simplifies SLOB (at this point slob may be broken in mm. This should fix
it).Signed-off-by: Christoph Lameter
Cc: Matt Mackall
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
If a zone is unpopulated then we do not need to check for pages that are to
be drained and also not for vm counters that may need to be updated.Signed-off-by: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Free one_page currently adds the page to a fake list and calls
free_page_bulk. Fee_page_bulk takes it off again and then calles
__free_one_page.Make free_one_page go directly to __free_one_page. Saves list on / off and
a temporary list in free_one_page for higher ordered pages.Signed-off-by: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
On High end systems (1024 or so cpus) this can potentially cause stack
overflow. Fix the stack usage.Signed-off-by: Suresh Siddha
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
In many places we will need to use the same combination of flags. Specify
a single GFP_THISNODE definition for ease of use in gfp.h.Signed-off-by: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
There are frequent references to *z in get_page_from_freelist.
Add an explicit zone variable that can be used in all these places.
Signed-off-by: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
If the user specified a node where we should move the page to then we
really do not want any other node.Signed-off-by: Christoph Lameter
Cc: Andy Whitcroft
Cc: Mel Gorman
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
…mory policy restrictions
Add a new gfp flag __GFP_THISNODE to avoid fallback to other nodes. This
flag is essential if a kernel component requires memory to be located on a
certain node. It will be needed for alloc_pages_node() to force allocation
on the indicated node and for alloc_pages() to force allocation on the
current node.Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org> -
Place the alien array cache locks of on slab malloc slab caches on a
seperate lockdep class. This avoids false positives from lockdep[akpm@osdl.org: build fix]
Signed-off-by: Ravikiran Thirumalai
Signed-off-by: Shai Fultheim
Cc: Thomas Gleixner
Acked-by: Arjan van de Ven
Cc: Ingo Molnar
Cc: Pekka Enberg
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
It is fairly easy to get a system to oops by simply sizing a cache via
/proc in such a way that one of the chaches (shared is easiest) becomes
bigger than the maximum allowed slab allocation size. This occurs because
enable_cpucache() fails if it cannot reallocate some caches.However, enable_cpucache() is used for multiple purposes: resizing caches,
cache creation and bootstrap.If the slab is already up then we already have working caches. The resize
can fail without a problem. We just need to return the proper error code.
F.e. after this patch:# echo "size-64 10000 50 1000" >/proc/slabinfo
-bash: echo: write error: Cannot allocate memorynotice no OOPS.
If we are doing a kmem_cache_create() then we also should not panic but
return -ENOMEM.If on the other hand we do not have a fully bootstrapped slab allocator yet
then we should indeed panic since we are unable to bring up the slab to its
full functionality.Signed-off-by: Christoph Lameter
Cc: Pekka Enberg
Cc: Manfred Spraul
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The ability to free memory allocated to a slab cache is also useful if an
error occurs during setup of a slab. So extract the function.Signed-off-by: Christoph Lameter
Cc: Pekka Enberg
Cc: Manfred Spraul
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
[akpm@osdl.org: export fix]
Signed-off-by: Christoph Hellwig
Acked-by: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Let's try to keep mm/ comments more useful and up to date. This is a start.
Signed-off-by: Nick Piggin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Also, checks if we get a valid slabp_cache for off slab slab-descriptors.
We should always get this. If we don't, then in that case we, will have to
disable off-slab descriptors for this cache and do the calculations again.
This is a rare case, so add a BUG_ON, for now, just in case.Signed-off-by: Alok N Kataria
Signed-off-by: Ravikiran Thirumalai
Signed-off-by: Shai Fultheim
Cc: Pekka Enberg
Cc: Manfred Spraul
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Introduce ARCH_LOW_ADDRESS_LIMIT which can be set per architecture to
override the 4GB default limit used by the bootmem allocater within
__alloc_bootmem_low() and __alloc_bootmem_low_node(). E.g. s390 needs a
2GB limit instead of 4GB.Acked-by: Ingo Molnar
Cc: Martin Schwidefsky
Signed-off-by: Heiko Carstens
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Print the name of the task invoking the OOM killer. Could make debugging
easier.Signed-off-by: Nick Piggin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Skip kernel threads, rather than having them return 0 from badness.
Theoretically, badness might truncate all results to 0, thus a kernel thread
might be picked first, causing an infinite loop.Signed-off-by: Nick Piggin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
PF_SWAPOFF processes currently cause select_bad_process to return straight
away. Instead, give them high priority, so we will kill them first, however
we also first ensure no parallel OOM kills are happening at the same time.Signed-off-by: Nick Piggin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Having the oomkilladj == OOM_DISABLE check before the releasing check means
that oomkilladj == OOM_DISABLE tasks exiting will not stop the OOM killer.Moving the test down will give the desired behaviour. Also: it will allow
them to "OOM-kill" themselves if they are exiting. As per the previous patch,
this is required to prevent OOM killer deadlocks (and they don't actually get
killed, because they're already exiting -- they're simply allowed access to
memory reserves).Signed-off-by: Nick Piggin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
