16 Dec, 2009
40 commits
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Commit c04fc586c (mm: show node to memory section relationship with
symlinks in sysfs) created symlinks from nodes to memory sections, e.g./sys/devices/system/node/node1/memory135 -> ../../memory/memory135
If you're examining the memory section though and are wondering what node
it might belong to, you can find it by grovelling around in sysfs, but
it's a little cumbersome.Add a reverse symlink for each memory section that points back to the
node to which it belongs.Signed-off-by: Alex Chiang
Cc: Gary Hade
Cc: Badari Pulavarty
Cc: Ingo Molnar
Acked-by: David Rientjes
Cc: Greg KH
Cc: Randy Dunlap
Cc: David Rientjes
Cc: KOSAKI Motohiro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
When do_nonlinear_fault() realizes that the page table must have been
corrupted for it to have been called, it does print_bad_pte() and returns
... VM_FAULT_OOM, which is hard to understand.It made some sense when I did it for 2.6.15, when do_page_fault() just
killed the current process; but nowadays it lets the OOM killer decide who
to kill - so page table corruption in one process would be liable to kill
another.Change it to return VM_FAULT_SIGBUS instead: that doesn't guarantee that
the process will be killed, but is good enough for such a rare
abnormality, accompanied as it is by the "BUG: Bad page map" message.And recent HWPOISON work has copied that code into do_swap_page(), when it
finds an impossible swap entry: fix that to VM_FAULT_SIGBUS too.Signed-off-by: Hugh Dickins
Cc: Izik Eidus
Cc: Andrea Arcangeli
Cc: Nick Piggin
Reviewed-by: KOSAKI Motohiro
Cc: Rik van Riel
Cc: Lee Schermerhorn
Cc: Andi Kleen
Reviewed-by: KAMEZAWA Hiroyuki
Reviewed-by: Wu Fengguang
Reviewed-by: Minchan Kim
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
CONFIG_DEBUG_SPINLOCK adds 12 or 16 bytes to a 32- or 64-bit spinlock_t,
and CONFIG_DEBUG_LOCK_ALLOC adds another 12 or 24 bytes to it: lockdep
enables both of those, and CONFIG_LOCK_STAT adds 8 or 16 bytes to that.When 2.6.15 placed the split page table lock inside struct page (usually
sized 32 or 56 bytes), only CONFIG_DEBUG_SPINLOCK was a possibility, and
we ignored the enlargement (but fitted in CONFIG_GENERIC_LOCKBREAK's 4 by
letting the spinlock_t occupy both page->private and page->mapping).Should these debugging options be allowed to double the size of a struct
page, when only one minority use of the page (as a page table) needs to
fit a spinlock in there? Perhaps not.Take the easy way out: switch off SPLIT_PTLOCK_CPUS when DEBUG_SPINLOCK or
DEBUG_LOCK_ALLOC is in force. I've sometimes tried to be cleverer,
kmallocing a cacheline for the spinlock when it doesn't fit, but given up
each time. Falling back to mm->page_table_lock (as we do when ptlock is
not split) lets lockdep check out the strictest path anyway.And now that some arches allow 8192 cpus, use 999999 for infinity.
(What has this got to do with KSM swapping? It doesn't care about the
size of struct page, but may care about random junk in page->mapping - to
be explained separately later.)Signed-off-by: Hugh Dickins
Cc: Izik Eidus
Cc: Andrea Arcangeli
Cc: Nick Piggin
Cc: KOSAKI Motohiro
Cc: Rik van Riel
Cc: Lee Schermerhorn
Cc: Andi Kleen
Cc: KAMEZAWA Hiroyuki
Cc: Wu Fengguang
Cc: Minchan Kim
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
KSM swapping will know where page_referenced_one() and try_to_unmap_one()
should look. It could hack page->index to get them to do what it wants,
but it seems cleaner now to pass the address down to them.Make the same change to page_mkclean_one(), since it follows the same
pattern; but there's no real need in its case.Signed-off-by: Hugh Dickins
Cc: Izik Eidus
Cc: Andrea Arcangeli
Cc: Nick Piggin
Cc: KOSAKI Motohiro
Cc: Rik van Riel
Cc: Lee Schermerhorn
Cc: Andi Kleen
Cc: KAMEZAWA Hiroyuki
Cc: Wu Fengguang
Cc: Minchan Kim
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Remove three degrees of obfuscation, left over from when we had
CONFIG_UNEVICTABLE_LRU. MLOCK_PAGES is CONFIG_HAVE_MLOCKED_PAGE_BIT is
CONFIG_HAVE_MLOCK is CONFIG_MMU. rmap.o (and memory-failure.o) are only
built when CONFIG_MMU, so don't need such conditions at all.Somehow, I feel no compulsion to remove the CONFIG_HAVE_MLOCK* lines from
169 defconfigs: leave those to evolve in due course.Signed-off-by: Hugh Dickins
Cc: Izik Eidus
Cc: Andrea Arcangeli
Cc: Nick Piggin
Reviewed-by: KOSAKI Motohiro
Cc: Rik van Riel
Cc: Lee Schermerhorn
Cc: Andi Kleen
Cc: KAMEZAWA Hiroyuki
Cc: Wu Fengguang
Cc: Minchan Kim
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
There's contorted mlock/munlock handling in try_to_unmap_anon() and
try_to_unmap_file(), which we'd prefer not to repeat for KSM swapping.
Simplify it by moving it all down into try_to_unmap_one().One thing is then lost, try_to_munlock()'s distinction between when no vma
holds the page mlocked, and when a vma does mlock it, but we could not get
mmap_sem to set the page flag. But its only caller takes no interest in
that distinction (and is better testing SWAP_MLOCK anyway), so let's keep
the code simple and return SWAP_AGAIN for both cases.try_to_unmap_file()'s TTU_MUNLOCK nonlinear handling was particularly
amusing: once unravelled, it turns out to have been choosing between two
different ways of doing the same nothing. Ah, no, one way was actually
returning SWAP_FAIL when it meant to return SWAP_SUCCESS.[kosaki.motohiro@jp.fujitsu.com: comment adding to mlocking in try_to_unmap_one]
[akpm@linux-foundation.org: remove test of MLOCK_PAGES]
Signed-off-by: Hugh Dickins
Cc: Izik Eidus
Cc: Andrea Arcangeli
Cc: Nick Piggin
Cc: Rik van Riel
Cc: Lee Schermerhorn
Cc: Andi Kleen
Cc: KAMEZAWA Hiroyuki
Cc: Wu Fengguang
Cc: Minchan Kim
Signed-off-by: KOSAKI Motohiro
Cc: Andi Kleen
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
At present we define PageAnon(page) by the low PAGE_MAPPING_ANON bit set
in page->mapping, with the higher bits a pointer to the anon_vma; and have
defined PageKsm(page) as that with NULL anon_vma.But KSM swapping will need to store a pointer there: so in preparation for
that, now define PAGE_MAPPING_FLAGS as the low two bits, including
PAGE_MAPPING_KSM (always set along with PAGE_MAPPING_ANON, until some
other use for the bit emerges).Declare page_rmapping(page) to return the pointer part of page->mapping,
and page_anon_vma(page) to return the anon_vma pointer when that's what it
is. Use these in a few appropriate places: notably, unuse_vma() has been
testing page->mapping, but is better to be testing page_anon_vma() (cases
may be added in which flag bits are set without any pointer).Signed-off-by: Hugh Dickins
Cc: Izik Eidus
Cc: Andrea Arcangeli
Cc: Nick Piggin
Cc: KOSAKI Motohiro
Reviewed-by: Rik van Riel
Cc: Lee Schermerhorn
Cc: Andi Kleen
Cc: KAMEZAWA Hiroyuki
Cc: Wu Fengguang
Cc: Minchan Kim
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
If reclaim fails to make sufficient progress, the priority is raised.
Once the priority is higher, kswapd starts waiting on congestion.
However, if the zone is below the min watermark then kswapd needs to
continue working without delay as there is a danger of an increased rate
of GFP_ATOMIC allocation failure.This patch changes the conditions under which kswapd waits on congestion
by only going to sleep if the min watermarks are being met.[mel@csn.ul.ie: add stats to track how relevant the logic is]
[mel@csn.ul.ie: make kswapd only check its own zones and rename the relevant counters]
Signed-off-by: KOSAKI Motohiro
Signed-off-by: Mel Gorman
Reviewed-by: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
After kswapd balances all zones in a pgdat, it goes to sleep. In the
event of no IO congestion, kswapd can go to sleep very shortly after the
high watermark was reached. If there are a constant stream of allocations
from parallel processes, it can mean that kswapd went to sleep too quickly
and the high watermark is not being maintained for sufficient length time.This patch makes kswapd go to sleep as a two-stage process. It first
tries to sleep for HZ/10. If it is woken up by another process or the
high watermark is no longer met, it's considered a premature sleep and
kswapd continues work. Otherwise it goes fully to sleep.This adds more counters to distinguish between fast and slow breaches of
watermarks. A "fast" premature sleep is one where the low watermark was
hit in a very short time after kswapd going to sleep. A "slow" premature
sleep indicates that the high watermark was breached after a very short
interval.Signed-off-by: Mel Gorman
Cc: Frans Pop
Cc: KOSAKI Motohiro
Cc: Rik van Riel
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
When the code jumps to the `out', `referenced' is still zero. So there is
no need to check it.Signed-off-by: Huang Shijie
Acked-by: Wu Fengguang
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Just simplify the code when `mlocked' is true.
Signed-off-by: Huang Shijie
Reviewed-by: KOSAKI Motohiro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Fix the comment for try_to_unmap_anon() with the new arguments.
Signed-off-by: Huang Shijie
Acked-by: Hugh Dickins
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Commit 543ade1fc9 ("Streamline generic_file_* interfaces and filemap
cleanups") removed generic_file_write() in filemap. Change the comment in
vmscan pageout() to __generic_file_aio_write().Signed-off-by: Vincent Li
Cc: Christoph Hellwig
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Seems that page_io.c doesn't really need to know that page_private(page)
is the swp_entry 'val'. Rework map_swap_page() to do what its name says
and map a page to a page offset in the swap space.The only other caller of map_swap_page() is internal to mm/swapfile.c and
it does want to map a swap entry to the 'sector'. So rename
map_swap_page() to map_swap_entry(), make it 'static' and and implement
map_swap_page() as a wrapper around that.Signed-off-by: Lee Schermerhorn
Cc: Hugh Dickins
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Reorder (and comment) the fields of swap_info_struct, to make better
use of its cachelines: it's good for swap_duplicate() in particular
if unsigned int max and swap_map are near the start.Signed-off-by: Hugh Dickins
Cc: KAMEZAWA Hiroyuki
Cc: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
While we're fiddling with the swap_map values, let's assign a particular
value to shmem/tmpfs swap pages: their swap counts are never incremented,
and it helps swapoff's try_to_unuse() a little if it can immediately
distinguish those pages from process pages.Since we've no use for SWAP_MAP_BAD | COUNT_CONTINUED,
we might as well use that 0xbf value for SWAP_MAP_SHMEM.Signed-off-by: Hugh Dickins
Reviewed-by: KAMEZAWA Hiroyuki
Cc: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Swap is duplicated (reference count incremented by one) whenever the same
swap page is inserted into another mm (when forking finds a swap entry in
place of a pte, or when reclaim unmaps a pte to insert the swap entry).swap_info_struct's vmalloc'ed swap_map is the array of these reference
counts: but what happens when the unsigned short (or unsigned char since
the preceding patch) is full? (and its high bit is kept for a cache flag)We then lose track of it, never freeing, leaving it in use until swapoff:
at which point we _hope_ that a single pass will have found all instances,
assume there are no more, and will lose user data if we're wrong.Swapping of KSM pages has not yet been enabled; but it is implemented,
and makes it very easy for a user to overflow the maximum swap count:
possible with ordinary process pages, but unlikely, even when pid_max
has been raised from PID_MAX_DEFAULT.This patch implements swap count continuations: when the count overflows,
a continuation page is allocated and linked to the original vmalloc'ed
map page, and this used to hold the continuation counts for that entry
and its neighbours. These continuation pages are seldom referenced:
the common paths all work on the original swap_map, only referring to
a continuation page when the low "digit" of a count is incremented or
decremented through SWAP_MAP_MAX.Signed-off-by: Hugh Dickins
Cc: KAMEZAWA Hiroyuki
Cc: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Halve the vmalloc'ed swap_map array from unsigned shorts to unsigned
chars: it's still very unusual to reach a swap count of 126, and the
next patch allows it to be extended indefinitely.Signed-off-by: Hugh Dickins
Reviewed-by: KAMEZAWA Hiroyuki
Cc: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Though swap_count() is useful, I'm finding that swap_has_cache() and
encode_swapmap() obscure what happens in the swap_map entry, just at
those points where I need to understand it. Remove them, and pass
more usable "usage" values to scan_swap_map(), swap_entry_free() and
__swap_duplicate(), instead of the SWAP_MAP and SWAP_CACHE enum.Signed-off-by: Hugh Dickins
Reviewed-by: KAMEZAWA Hiroyuki
Cc: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Move CONFIG_HIBERNATION's swapdev_block() into the main CONFIG_HIBERNATION
block, remove extraneous whitespace and return, fix typo in a comment.Signed-off-by: Hugh Dickins
Reviewed-by: KAMEZAWA Hiroyuki
Cc: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Make better use of the space by folding first swap_extent into its
swap_info_struct, instead of just the list_head: swap partitions need
only that one, and for others it's used as a circular list anyway.[jirislaby@gmail.com: fix crash on double swapon]
Signed-off-by: Hugh Dickins
Cc: KAMEZAWA Hiroyuki
Cc: Rik van Riel
Signed-off-by: Jiri Slaby
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The swap_info_struct is only 76 or 104 bytes, but it does seem wrong
to reserve an array of about 30 of them in bss, when most people will
want only one. Change swap_info[] to an array of pointers.That does need a "type" field in the structure: pack it as a char with
next type and short prio (aha, char is unsigned by default on PowerPC).
Use the (admittedly peculiar) name "type" throughout for this index./proc/swaps does not take swap_lock: I wouldn't want it to, but do take
care with barriers when adding a new item to the array (never removed).Signed-off-by: Hugh Dickins
Reviewed-by: KAMEZAWA Hiroyuki
Acked-by: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The swap_info_struct is mostly private to mm/swapfile.c, with only
one other in-tree user: get_swap_bio(). Adjust its interface to
map_swap_page(), so that we can then remove get_swap_info_struct().But there is a popular user out-of-tree, TuxOnIce: so leave the
declaration of swap_info_struct in linux/swap.h.Signed-off-by: Hugh Dickins
Cc: Nigel Cunningham
Cc: KAMEZAWA Hiroyuki
Reviewed-by: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
- avoid wasting more precious resources (DMA or DMA32 pools), when
being called through vmalloc_32{,_user}()
- explicitly allow using high memory here even if the outer allocation
request doesn't allow itSigned-off-by: Jan Beulich
Acked-by: Hugh Dickins
Cc: Nick Piggin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Objects passed to NODEMASK_ALLOC() are relatively small in size and are
backed by slab caches that are not of large order, traditionally never
greater than PAGE_ALLOC_COSTLY_ORDER.Thus, using GFP_KERNEL for these allocations on large machines when
CONFIG_NODES_SHIFT > 8 will cause the page allocator to loop endlessly in
the allocation attempt, each time invoking both direct reclaim or the oom
killer.This is of particular interest when using NODEMASK_ALLOC() from a
mempolicy context (either directly in mm/mempolicy.c or the mempolicy
constrained hugetlb allocations) since the oom killer always kills current
when allocations are constrained by mempolicies. So for all present use
cases in the kernel, current would end up being oom killed when direct
reclaim fails. That would allow the NODEMASK_ALLOC() to succeed but
current would have sacrificed itself upon returning.This patch adds gfp flags to NODEMASK_ALLOC() to pass to kmalloc() on
CONFIG_NODES_SHIFT > 8; this parameter is a nop on other configurations.
All current use cases either directly from hugetlb code or indirectly via
NODEMASK_SCRATCH() union __GFP_NORETRY to avoid direct reclaim and the oom
killer when the slab allocator needs to allocate additional pages.The side-effect of this change is that all current use cases of either
NODEMASK_ALLOC() or NODEMASK_SCRATCH() need appropriate -ENOMEM handling
when the allocation fails (never for CONFIG_NODES_SHIFT
Acked-by: KAMEZAWA Hiroyuki
Cc: Lee Schermerhorn
Cc: Mel Gorman
Cc: Randy Dunlap
Cc: Nishanth Aravamudan
Cc: Andi Kleen
Cc: David Rientjes
Cc: Adam Litke
Cc: Andy Whitcroft
Cc: Eric Whitney
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Offload the registration and unregistration of per node hstate sysfs
attributes to a worker thread rather than attempt the
allocation/attachment or detachment/freeing of the attributes in the
context of the memory hotplug handler.I don't know that this is absolutely required, but the registration can
sleep in allocations and other mem hot plug handlers do it this way. If
it turns out this is NOT required, we can drop this patch.N.B., Only tested build, boot, libhugetlbfs regression.
i.e., no memory hotplug testing.Signed-off-by: Lee Schermerhorn
Reviewed-by: Andi Kleen
Cc: KAMEZAWA Hiroyuki
Cc: Lee Schermerhorn
Cc: Mel Gorman
Cc: Randy Dunlap
Cc: Nishanth Aravamudan
Cc: David Rientjes
Cc: Adam Litke
Cc: Andy Whitcroft
Cc: Eric Whitney
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Register per node hstate attributes only for nodes with memory. As
suggested by David Rientjes.With Memory Hotplug, memory can be added to a memoryless node and a node
with memory can become memoryless. Therefore, add a memory on/off-line
notifier callback to [un]register a node's attributes on transition
to/from memoryless state.N.B., Only tested build, boot, libhugetlbfs regression.
i.e., no memory hotplug testing.Signed-off-by: Lee Schermerhorn
Reviewed-by: Andi Kleen
Acked-by: David Rientjes
Cc: KAMEZAWA Hiroyuki
Cc: Lee Schermerhorn
Cc: Mel Gorman
Cc: Randy Dunlap
Cc: Nishanth Aravamudan
Cc: Adam Litke
Cc: Andy Whitcroft
Cc: Eric Whitney
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
When memory is hot-removed, its node must be cleared in N_HIGH_MEMORY if
there are no present pages left.In such a situation, kswapd must also be stopped since it has nothing left
to do.Signed-off-by: David Rientjes
Signed-off-by: Lee Schermerhorn
Cc: Christoph Lameter
Cc: Yasunori Goto
Cc: Mel Gorman
Cc: Rafael J. Wysocki
Cc: Rik van Riel
Cc: KAMEZAWA Hiroyuki
Cc: Lee Schermerhorn
Cc: Mel Gorman
Cc: Randy Dunlap
Cc: Nishanth Aravamudan
Cc: Andi Kleen
Cc: David Rientjes
Cc: Adam Litke
Cc: Andy Whitcroft
Cc: Eric Whitney
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Register per node hstate sysfs attributes only for nodes with memory.
Global replacement of 'all online nodes" with "all nodes with memory" in
mm/hugetlb.c. Suggested by David Rientjes.A subsequent patch will handle adding/removing of per node hstate sysfs
attributes when nodes transition to/from memoryless state via memory
hotplug.NOTE: this patch has not been tested with memoryless nodes.
Signed-off-by: Lee Schermerhorn
Reviewed-by: Andi Kleen
Cc: KAMEZAWA Hiroyuki
Cc: Mel Gorman
Cc: Randy Dunlap
Cc: Nishanth Aravamudan
Acked-by: David Rientjes
Cc: Adam Litke
Cc: Andy Whitcroft
Cc: Eric Whitney
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Update the kernel huge tlb documentation to describe the numa memory
policy based huge page management. Additionaly, the patch includes a fair
amount of rework to improve consistency, eliminate duplication and set the
context for documenting the memory policy interaction.Signed-off-by: Lee Schermerhorn
Acked-by: David Rientjes
Acked-by: Mel Gorman
Reviewed-by: Andi Kleen
Cc: KAMEZAWA Hiroyuki
Cc: Lee Schermerhorn
Cc: Randy Dunlap
Cc: Nishanth Aravamudan
Cc: Adam Litke
Cc: Andy Whitcroft
Cc: Eric Whitney
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Add the per huge page size control/query attributes to the per node
sysdevs:/sys/devices/system/node/node/hugepages/hugepages-/
nr_hugepages - r/w
free_huge_pages - r/o
surplus_huge_pages - r/oThe patch attempts to re-use/share as much of the existing global hstate
attribute initialization and handling, and the "nodes_allowed" constraint
processing as possible.Calling set_max_huge_pages() with no node indicates a change to global
hstate parameters. In this case, any non-default task mempolicy will be
used to generate the nodes_allowed mask. A valid node id indicates an
update to that node's hstate parameters, and the count argument specifies
the target count for the specified node. From this info, we compute the
target global count for the hstate and construct a nodes_allowed node mask
contain only the specified node.Setting the node specific nr_hugepages via the per node attribute
effectively ignores any task mempolicy or cpuset constraints.With this patch:
(me):ls /sys/devices/system/node/node0/hugepages/hugepages-2048kB
./ ../ free_hugepages nr_hugepages surplus_hugepagesStarting from:
Node 0 HugePages_Total: 0
Node 0 HugePages_Free: 0
Node 0 HugePages_Surp: 0
Node 1 HugePages_Total: 0
Node 1 HugePages_Free: 0
Node 1 HugePages_Surp: 0
Node 2 HugePages_Total: 0
Node 2 HugePages_Free: 0
Node 2 HugePages_Surp: 0
Node 3 HugePages_Total: 0
Node 3 HugePages_Free: 0
Node 3 HugePages_Surp: 0
vm.nr_hugepages = 0Allocate 16 persistent huge pages on node 2:
(me):echo 16 >/sys/devices/system/node/node2/hugepages/hugepages-2048kB/nr_hugepages[Note that this is equivalent to:
numactl -m 2 hugeadmin --pool-pages-min 2M:+16
]Yields:
Node 0 HugePages_Total: 0
Node 0 HugePages_Free: 0
Node 0 HugePages_Surp: 0
Node 1 HugePages_Total: 0
Node 1 HugePages_Free: 0
Node 1 HugePages_Surp: 0
Node 2 HugePages_Total: 16
Node 2 HugePages_Free: 16
Node 2 HugePages_Surp: 0
Node 3 HugePages_Total: 0
Node 3 HugePages_Free: 0
Node 3 HugePages_Surp: 0
vm.nr_hugepages = 16Global controls work as expected--reduce pool to 8 persistent huge pages:
(me):echo 8 >/sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepagesNode 0 HugePages_Total: 0
Node 0 HugePages_Free: 0
Node 0 HugePages_Surp: 0
Node 1 HugePages_Total: 0
Node 1 HugePages_Free: 0
Node 1 HugePages_Surp: 0
Node 2 HugePages_Total: 8
Node 2 HugePages_Free: 8
Node 2 HugePages_Surp: 0
Node 3 HugePages_Total: 0
Node 3 HugePages_Free: 0
Node 3 HugePages_Surp: 0Signed-off-by: Lee Schermerhorn
Acked-by: Mel Gorman
Reviewed-by: Andi Kleen
Cc: KAMEZAWA Hiroyuki
Cc: Randy Dunlap
Cc: Nishanth Aravamudan
Cc: David Rientjes
Cc: Adam Litke
Cc: Andy Whitcroft
Cc: Eric Whitney
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Move definition of NUMA_NO_NODE from ia64 and x86_64 arch specific headers
to generic header 'linux/numa.h' for use in generic code. NUMA_NO_NODE
replaces bare '-1' where it's used in this series to indicate "no node id
specified". Ultimately, it can be used to replace the -1 elsewhere where
it is used similarly.Signed-off-by: Lee Schermerhorn
Acked-by: David Rientjes
Acked-by: Mel Gorman
Reviewed-by: Andi Kleen
Cc: KAMEZAWA Hiroyuki
Cc: Randy Dunlap
Cc: Nishanth Aravamudan
Cc: Adam Litke
Cc: Andy Whitcroft
Cc: Eric Whitney
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This patch derives a "nodes_allowed" node mask from the numa mempolicy of
the task modifying the number of persistent huge pages to control the
allocation, freeing and adjusting of surplus huge pages when the pool page
count is modified via the new sysctl or sysfs attribute
"nr_hugepages_mempolicy". The nodes_allowed mask is derived as follows:* For "default" [NULL] task mempolicy, a NULL nodemask_t pointer
is produced. This will cause the hugetlb subsystem to use
node_online_map as the "nodes_allowed". This preserves the
behavior before this patch.
* For "preferred" mempolicy, including explicit local allocation,
a nodemask with the single preferred node will be produced.
"local" policy will NOT track any internode migrations of the
task adjusting nr_hugepages.
* For "bind" and "interleave" policy, the mempolicy's nodemask
will be used.
* Other than to inform the construction of the nodes_allowed node
mask, the actual mempolicy mode is ignored. That is, all modes
behave like interleave over the resulting nodes_allowed mask
with no "fallback".See the updated documentation [next patch] for more information
about the implications of this patch.Examples:
Starting with:
Node 0 HugePages_Total: 0
Node 1 HugePages_Total: 0
Node 2 HugePages_Total: 0
Node 3 HugePages_Total: 0Default behavior [with or without this patch] balances persistent
hugepage allocation across nodes [with sufficient contiguous memory]:sysctl vm.nr_hugepages[_mempolicy]=32
yields:
Node 0 HugePages_Total: 8
Node 1 HugePages_Total: 8
Node 2 HugePages_Total: 8
Node 3 HugePages_Total: 8Of course, we only have nr_hugepages_mempolicy with the patch,
but with default mempolicy, nr_hugepages_mempolicy behaves the
same as nr_hugepages.Applying mempolicy--e.g., with numactl [using '-m' a.k.a.
'--membind' because it allows multiple nodes to be specified
and it's easy to type]--we can allocate huge pages on
individual nodes or sets of nodes. So, starting from the
condition above, with 8 huge pages per node, add 8 more to
node 2 using:numactl -m 2 sysctl vm.nr_hugepages_mempolicy=40
This yields:
Node 0 HugePages_Total: 8
Node 1 HugePages_Total: 8
Node 2 HugePages_Total: 16
Node 3 HugePages_Total: 8The incremental 8 huge pages were restricted to node 2 by the
specified mempolicy.Similarly, we can use mempolicy to free persistent huge pages
from specified nodes:numactl -m 0,1 sysctl vm.nr_hugepages_mempolicy=32
yields:
Node 0 HugePages_Total: 4
Node 1 HugePages_Total: 4
Node 2 HugePages_Total: 16
Node 3 HugePages_Total: 8The 8 huge pages freed were balanced over nodes 0 and 1.
[rientjes@google.com: accomodate reworked NODEMASK_ALLOC]
Signed-off-by: David Rientjes
Signed-off-by: Lee Schermerhorn
Acked-by: Mel Gorman
Reviewed-by: Andi Kleen
Cc: KAMEZAWA Hiroyuki
Cc: Randy Dunlap
Cc: Nishanth Aravamudan
Cc: Adam Litke
Cc: Andy Whitcroft
Cc: Eric Whitney
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Factor init_nodemask_of_node() out of the nodemask_of_node() macro.
This will be used to populate the huge pages "nodes_allowed" nodemask for
a single node when basing nodes_allowed on a preferred/local mempolicy or
when a persistent huge page pool page count is modified via a per node
sysfs attribute.Signed-off-by: Lee Schermerhorn
Acked-by: Mel Gorman
Reviewed-by: Andi Kleen
Cc: KAMEZAWA Hiroyuki
Cc: Randy Dunlap
Cc: Nishanth Aravamudan
Acked-by: David Rientjes
Cc: Adam Litke
Cc: Andy Whitcroft
Cc: Eric Whitney
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
In preparation for constraining huge page allocation and freeing by the
controlling task's numa mempolicy, add a "nodes_allowed" nodemask pointer
to the allocate, free and surplus adjustment functions. For now, pass
NULL to indicate default behavior--i.e., use node_online_map. A
subsqeuent patch will derive a non-default mask from the controlling
task's numa mempolicy.Note that this method of updating the global hstate nr_hugepages under the
constraint of a nodemask simplifies keeping the global state
consistent--especially the number of persistent and surplus pages relative
to reservations and overcommit limits. There are undoubtedly other ways
to do this, but this works for both interfaces: mempolicy and per node
attributes.[rientjes@google.com: fix HIGHMEM compile error]
Signed-off-by: Lee Schermerhorn
Reviewed-by: Mel Gorman
Acked-by: David Rientjes
Reviewed-by: Andi Kleen
Cc: KAMEZAWA Hiroyuki
Cc: Randy Dunlap
Cc: Nishanth Aravamudan
Cc: Andi Kleen
Cc: Adam Litke
Cc: Andy Whitcroft
Cc: Eric Whitney
Cc: Christoph Lameter
Signed-off-by: David Rientjes
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Modify the hstate_next_node* functions to allow them to be called to
obtain the "start_nid". Then, whereas prior to this patch we
unconditionally called hstate_next_node_to_{alloc|free}(), whether or not
we successfully allocated/freed a huge page on the node, now we only call
these functions on failure to alloc/free to advance to next allowed node.Factor out the next_node_allowed() function to handle wrap at end of
node_online_map. In this version, the allowed nodes include all of the
online nodes.Signed-off-by: Lee Schermerhorn
Reviewed-by: Mel Gorman
Acked-by: David Rientjes
Reviewed-by: Andi Kleen
Cc: KAMEZAWA Hiroyuki
Cc: Randy Dunlap
Cc: Nishanth Aravamudan
Cc: Andi Kleen
Cc: Adam Litke
Cc: Andy Whitcroft
Cc: Eric Whitney
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This is a series of patches to provide control over the location of the
allocation and freeing of persistent huge pages on a NUMA platform.
Please consider for merging into mmotm.This series uses two mechanisms to constrain the nodes from which
persistent huge pages are allocated: 1) the task NUMA mempolicy of the
task modifying a new sysctl "nr_hugepages_mempolicy", based on a
suggestion by Mel Gorman; and 2) a subset of the hugepages hstate sysfs
attributes have been added [in V4] to each node system device under:/sys/devices/node/node[0-9]*/hugepages
The per node attibutes allow direct assignment of a huge page count on a
specific node, regardless of the task's mempolicy or cpuset constraints.This patch:
NODEMASK_ALLOC(x, m) assumes x is a type of struct, which is unnecessary.
It's perfectly reasonable to use this macro to allocate a nodemask_t,
which is anonymous, either dynamically or on the stack depending on
NODES_SHIFT.Signed-off-by: David Rientjes
Signed-off-by: Lee Schermerhorn
Acked-by: KAMEZAWA Hiroyuki
Cc: Mel Gorman
Cc: Randy Dunlap
Cc: Nishanth Aravamudan
Cc: Andi Kleen
Cc: David Rientjes
Cc: Adam Litke
Cc: Andy Whitcroft
Cc: Eric Whitney
Cc: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Christoph pointed out inc_zone_page_state(NR_ISOLATED) should be placed
in right after isolate_page().This patch does it.
Reviewed-by: Christoph Lameter
Signed-off-by: KOSAKI Motohiro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Signed-off-by: Wu Fengguang
Cc: Andi Kleen
Cc: Avi Kivity
Cc: Greg Kroah-Hartman
Cc: Johannes Berg
Cc: Marcelo Tosatti
Cc: Mark Brown
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Also rename "len" to "sz". No behavior change.
Signed-off-by: Wu Fengguang
Cc: Andi Kleen
Cc: Avi Kivity
Cc: Greg Kroah-Hartman
Cc: Johannes Berg
Cc: Marcelo Tosatti
Cc: Mark Brown
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
