09 Jun, 2010
2 commits
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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
Reviewed-by: Christoph Hellwig
Signed-off-by: Linus Torvalds -
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=-85This 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 17bc6c30cf6bfffd816bdc53682dd46fc34a2cf4 ("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
Reviewed-by: Christoph Hellwig
Signed-off-by: Linus Torvalds
05 Jun, 2010
4 commits
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* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
Minix: Clean up left over label
fix truncate inode time modification breakage
fix setattr error handling in sysfs, configfs
fcntl: return -EFAULT if copy_to_user fails
wrong type for 'magic' argument in simple_fill_super()
fix the deadlock in qib_fs
mqueue doesn't need make_bad_inode() -
* 'for-linus' of git://git.kernel.dk/linux-2.6-block: (27 commits)
block: make blk_init_free_list and elevator_init idempotent
block: avoid unconditionally freeing previously allocated request_queue
pipe: change /proc/sys/fs/pipe-max-pages to byte sized interface
pipe: change the privilege required for growing a pipe beyond system max
pipe: adjust minimum pipe size to 1 page
block: disable preemption before using sched_clock()
cciss: call BUG() earlier
Preparing 8.3.8rc2
drbd: Reduce verbosity
drbd: use drbd specific ratelimit instead of global printk_ratelimit
drbd: fix hang on local read errors while disconnected
drbd: Removed the now empty w_io_error() function
drbd: removed duplicated #includes
drbd: improve usage of MSG_MORE
drbd: need to set socket bufsize early to take effect
drbd: improve network latency, TCP_QUICKACK
drbd: Revert "drbd: Create new current UUID as late as possible"
brd: support discard
Revert "writeback: fix WB_SYNC_NONE writeback from umount"
Revert "writeback: ensure that WB_SYNC_NONE writeback with sb pinned is sync"
... -
Greg Thelen reported recent Johannes's stack diet patch makes kernel hang.
His test is following.mount -t cgroup none /cgroups -o memory
mkdir /cgroups/cg1
echo $$ > /cgroups/cg1/tasks
dd bs=1024 count=1024 if=/dev/null of=/data/foo
echo $$ > /cgroups/tasks
echo 1 > /cgroups/cg1/memory.force_emptyActually, This OOM hard to try logic have been corrupted since following
two years old patch.commit a41f24ea9fd6169b147c53c2392e2887cc1d9247
Author: Nishanth Aravamudan
Date: Tue Apr 29 00:58:25 2008 -0700page allocator: smarter retry of costly-order allocations
Original intention was "return success if the system have shrinkable zones
though priority==0 reclaim was failure". But the above patch changed to
"return nr_reclaimed if .....". Oh, That forgot nr_reclaimed may be 0 if
priority==0 reclaim failure.And Johannes's patch 0aeb2339e54e ("vmscan: remove all_unreclaimable scan
control") made it more corrupt. Originally, priority==0 reclaim failure
on memcg return 0, but this patch changed to return 1. It totally
confused memcg.This patch fixes it completely.
Reported-by: Greg Thelen
Signed-off-by: KOSAKI Motohiro
Acked-by: Johannes Weiner
Acked-by: KAMEZAWA Hiroyuki
Tested-by: Greg Thelen
Acked-by: Balbir Singh
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
mtime and ctime should be changed only if the file size has actually
changed. Patches changing ext2 and tmpfs from vmtruncate to new truncate
sequence has caused regressions where they always update timestamps.There is some strange cases in POSIX where truncate(2) must not update
times unless the size has acutally changed, see 6e656be89.This area is all still rather buggy in different ways in a lot of
filesystems and needs a cleanup and audit (ideally the vfs will provide
a simple attribute or call to direct all filesystems exactly which
attributes to change). But coming up with the best solution will take a
while and is not appropriate for rc anyway.So fix recent regression for now.
Signed-off-by: Nick Piggin
Signed-off-by: Al Viro
01 Jun, 2010
2 commits
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Conflicts:
fs/pipe.cSigned-off-by: Jens Axboe
-
This reverts commit e913fc825dc685a444cb4c1d0f9d32f372f59861.
We are investigating a hang associated with the WB_SYNC_NONE changes,
so revert them for now.Conflicts:
fs/fs-writeback.c
mm/page-writeback.cSigned-off-by: Jens Axboe
31 May, 2010
2 commits
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* 'slub/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6:
SLUB: Allow full duplication of kmalloc array for 390
slub: move kmem_cache_node into it's own cacheline -
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
mm: export generic_pipe_buf_*() to modules
fuse: support splice() reading from fuse device
fuse: allow splice to move pages
mm: export remove_from_page_cache() to modules
mm: export lru_cache_add_*() to modules
fuse: support splice() writing to fuse device
fuse: get page reference for readpages
fuse: use get_user_pages_fast()
fuse: remove unneeded variable
28 May, 2010
20 commits
-
Cc: Christoph Hellwig
Acked-by: Hugh Dickins
Signed-off-by: Nick Piggin
Signed-off-by: Al Viro -
Introduce a new truncate calling sequence into fs/mm subsystems. Rather than
setattr > vmtruncate > truncate, have filesystems call their truncate sequence
from ->setattr if filesystem specific operations are required. vmtruncate is
deprecated, and truncate_pagecache and inode_newsize_ok helpers introduced
previously should be used.simple_setattr is introduced for simple in-ram filesystems to implement
the new truncate sequence. Eventually all filesystems should be converted
to implement a setattr, and the default code in notify_change should go
away.simple_setsize is also introduced to perform just the ATTR_SIZE portion
of simple_setattr (ie. changing i_size and trimming pagecache).To implement the new truncate sequence:
- filesystem specific manipulations (eg freeing blocks) must be done in
the setattr method rather than ->truncate.
- vmtruncate can not be used by core code to trim blocks past i_size in
the event of write failure after allocation, so this must be performed
in the fs code.
- convert usage of helpers block_write_begin, nobh_write_begin,
cont_write_begin, and *blockdev_direct_IO* to use _newtrunc postfixed
variants. These avoid calling vmtruncate to trim blocks (see previous).
- inode_setattr should not be used. generic_setattr is a new function
to be used to copy simple attributes into the generic inode.
- make use of the better opportunity to handle errors with the new sequence.Big problem with the previous calling sequence: the filesystem is not called
until i_size has already changed. This means it is not allowed to fail the
call, and also it does not know what the previous i_size was. Also, generic
code calling vmtruncate to truncate allocated blocks in case of error had
no good way to return a meaningful error (or, for example, atomically handle
block deallocation).Cc: Christoph Hellwig
Acked-by: Jan Kara
Signed-off-by: Nick Piggin
Signed-off-by: Al Viro -
We don't name our generic fsync implementations very well currently.
The no-op implementation for in-memory filesystems currently is called
simple_sync_file which doesn't make too much sense to start with,
the the generic one for simple filesystems is called simple_fsync
which can lead to some confusion.This patch renames the generic file fsync method to generic_file_fsync
to match the other generic_file_* routines it is supposed to be used
with, and the no-op implementation to noop_fsync to make it obvious
what to expect. In addition add some documentation for both methods.Signed-off-by: Christoph Hellwig
Signed-off-by: Al Viro -
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (27 commits)
Btrfs: add more error checking to btrfs_dirty_inode
Btrfs: allow unaligned DIO
Btrfs: drop verbose enospc printk
Btrfs: Fix block generation verification race
Btrfs: fix preallocation and nodatacow checks in O_DIRECT
Btrfs: avoid ENOSPC errors in btrfs_dirty_inode
Btrfs: move O_DIRECT space reservation to btrfs_direct_IO
Btrfs: rework O_DIRECT enospc handling
Btrfs: use async helpers for DIO write checksumming
Btrfs: don't walk around with task->state != TASK_RUNNING
Btrfs: do aio_write instead of write
Btrfs: add basic DIO read/write support
direct-io: do not merge logically non-contiguous requests
direct-io: add a hook for the fs to provide its own submit_bio function
fs: allow short direct-io reads to be completed via buffered IO
Btrfs: Metadata ENOSPC handling for balance
Btrfs: Pre-allocate space for data relocation
Btrfs: Metadata ENOSPC handling for tree log
Btrfs: Metadata reservation for orphan inodes
Btrfs: Introduce global metadata reservation
... -
Example usage of generic "numa_mem_id()":
The mainline slab code, since ~ 2.6.19, does not handle memoryless nodes
well. Specifically, the "fast path"--____cache_alloc()--will never
succeed as slab doesn't cache offnode object on the per cpu queues, and
for memoryless nodes, all memory will be "off node" relative to
numa_node_id(). This adds significant overhead to all kmem cache
allocations, incurring a significant regression relative to earlier
kernels [from before slab.c was reorganized].This patch uses the generic topology function "numa_mem_id()" to return
the "effective local memory node" for the calling context. This is the
first node in the local node's generic fallback zonelist-- the same node
that "local" mempolicy-based allocations would use. This lets slab cache
these "local" allocations and avoid fallback/refill on every allocation.N.B.: Slab will need to handle node and memory hotplug events that could
change the value returned by numa_mem_id() for any given node if recent
changes to address memory hotplug don't already address this. E.g., flush
all per cpu slab queues before rebuilding the zonelists while the
"machine" is held in the stopped state.Performance impact on "hackbench 400 process 200"
2.6.34-rc3-mmotm-100405-1609 no-patch this-patch
ia64 no memoryless nodes [avg of 10]: 11.713 11.637 ~0.65 diff
ia64 cpus all on memless nodes [10]: 228.259 26.484 ~8.6x speedupThe slowdown of the patched kernel from ~12 sec to ~28 seconds when
configured with memoryless nodes is the result of all cpus allocating from
a single node's mm pagepool. The cache lines of the single node are
distributed/interleaved over the memory of the real physical nodes, but
the zone lock, list heads, ... of the single node with memory still each
live in a single cache line that is accessed from all processors.x86_64 [8x6 AMD] [avg of 40]: 2.883 2.845
Signed-off-by: Lee Schermerhorn
Cc: Tejun Heo
Cc: Mel Gorman
Cc: Christoph Lameter
Cc: Nick Piggin
Cc: David Rientjes
Cc: Eric Whitney
Cc: KAMEZAWA Hiroyuki
Cc: Ingo Molnar
Cc: Thomas Gleixner
Cc: "H. Peter Anvin"
Cc: "Luck, Tony"
Cc: Pekka Enberg
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Introduce numa_mem_id(), based on generic percpu variable infrastructure
to track "nearest node with memory" for archs that support memoryless
nodes.Define API in when CONFIG_HAVE_MEMORYLESS_NODES
defined, else stubs. Architectures will define HAVE_MEMORYLESS_NODES
if/when they support them.Archs can override definitions of:
numa_mem_id() - returns node number of "local memory" node
set_numa_mem() - initialize [this cpus'] per cpu variable 'numa_mem'
cpu_to_mem() - return numa_mem for specified cpu; may be used as lvalueGeneric initialization of 'numa_mem' occurs in __build_all_zonelists().
This will initialize the boot cpu at boot time, and all cpus on change of
numa_zonelist_order, or when node or memory hot-plug requires zonelist
rebuild. Archs that support memoryless nodes will need to initialize
'numa_mem' for secondary cpus as they're brought on-line.[akpm@linux-foundation.org: fix build]
Signed-off-by: Lee Schermerhorn
Signed-off-by: Christoph Lameter
Cc: Tejun Heo
Cc: Mel Gorman
Cc: Christoph Lameter
Cc: Nick Piggin
Cc: David Rientjes
Cc: Eric Whitney
Cc: KAMEZAWA Hiroyuki
Cc: Ingo Molnar
Cc: Thomas Gleixner
Cc: "H. Peter Anvin"
Cc: "Luck, Tony"
Cc: Pekka Enberg
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Rework the generic version of the numa_node_id() function to use the new
generic percpu variable infrastructure.Guard the new implementation with a new config option:
CONFIG_USE_PERCPU_NUMA_NODE_ID.
Archs which support this new implemention will default this option to 'y'
when NUMA is configured. This config option could be removed if/when all
archs switch over to the generic percpu implementation of numa_node_id().
Arch support involves:1) converting any existing per cpu variable implementations to use
this implementation. x86_64 is an instance of such an arch.
2) archs that don't use a per cpu variable for numa_node_id() will
need to initialize the new per cpu variable "numa_node" as cpus
are brought on-line. ia64 is an example.
3) Defining USE_PERCPU_NUMA_NODE_ID in arch dependent Kconfig--e.g.,
when NUMA is configured. This is required because I have
retained the old implementation by default to allow archs to
be modified incrementally, as desired.Subsequent patches will convert x86_64 and ia64 to use this implemenation.
Signed-off-by: Lee Schermerhorn
Cc: Tejun Heo
Cc: Mel Gorman
Reviewed-by: Christoph Lameter
Cc: Nick Piggin
Cc: David Rientjes
Cc: Eric Whitney
Cc: KAMEZAWA Hiroyuki
Cc: Ingo Molnar
Cc: Thomas Gleixner
Cc: "H. Peter Anvin"
Cc: "Luck, Tony"
Cc: Pekka Enberg
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
By the previous modification, the cpu notifier can return encapsulate
errno value. This converts the cpu notifiers for slab.Signed-off-by: Akinobu Mita
Cc: Christoph Lameter
Acked-by: Pekka Enberg
Cc: Matt Mackall
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
We have observed several workloads running on multi-node systems where
memory is assigned unevenly across the nodes in the system. There are
numerous reasons for this but one is the round-robin rotor in
cpuset_mem_spread_node().For example, a simple test that writes a multi-page file will allocate
pages on nodes 0 2 4 6 ... Odd nodes are skipped. (Sometimes it
allocates on odd nodes & skips even nodes).An example is shown below. The program "lfile" writes a file consisting
of 10 pages. The program then mmaps the file & uses get_mempolicy(...,
MPOL_F_NODE) to determine the nodes where the file pages were allocated.
The output is shown below:# ./lfile
allocated on nodes: 2 4 6 0 1 2 6 0 2There is a single rotor that is used for allocating both file pages & slab
pages. Writing the file allocates both a data page & a slab page
(buffer_head). This advances the RR rotor 2 nodes for each page
allocated.A quick confirmation seems to confirm this is the cause of the uneven
allocation:# echo 0 >/dev/cpuset/memory_spread_slab
# ./lfile
allocated on nodes: 6 7 8 9 0 1 2 3 4 5This patch introduces a second rotor that is used for slab allocations.
Signed-off-by: Jack Steiner
Acked-by: Christoph Lameter
Cc: Pekka Enberg
Cc: Paul Menage
Cc: Jack Steiner
Cc: Robin Holt
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Introduce struct mem_cgroup_thresholds. It helps to reduce number of
checks of thresholds type (memory or mem+swap).[akpm@linux-foundation.org: repair comment]
Signed-off-by: Kirill A. Shutemov
Cc: Phil Carmody
Cc: Balbir Singh
Cc: Daisuke Nishimura
Cc: KAMEZAWA Hiroyuki
Acked-by: Paul Menage
Cc: Li Zefan
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Since we are unable to handle an error returned by
cftype.unregister_event() properly, let's make the callback
void-returning.mem_cgroup_unregister_event() has been rewritten to be a "never fail"
function. On mem_cgroup_usage_register_event() we save old buffer for
thresholds array and reuse it in mem_cgroup_usage_unregister_event() to
avoid allocation.Signed-off-by: Kirill A. Shutemov
Acked-by: KAMEZAWA Hiroyuki
Cc: Phil Carmody
Cc: Balbir Singh
Cc: Daisuke Nishimura
Cc: Paul Menage
Cc: Li Zefan
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
FILE_MAPPED per memcg of migrated file cache is not properly updated,
because our hook in page_add_file_rmap() can't know to which memcg
FILE_MAPPED should be counted.Basically, this patch is for fixing the bug but includes some big changes
to fix up other messes.Now, at migrating mapped file, events happen in following sequence.
1. allocate a new page.
2. get memcg of an old page.
3. charge ageinst a new page before migration. But at this point,
no changes to new page's page_cgroup, no commit for the charge.
(IOW, PCG_USED bit is not set.)
4. page migration replaces radix-tree, old-page and new-page.
5. page migration remaps the new page if the old page was mapped.
6. Here, the new page is unlocked.
7. memcg commits the charge for newpage, Mark the new page's page_cgroup
as PCG_USED.Because "commit" happens after page-remap, we can count FILE_MAPPED
at "5", because we should avoid to trust page_cgroup->mem_cgroup.
if PCG_USED bit is unset.
(Note: memcg's LRU removal code does that but LRU-isolation logic is used
for helping it. When we overwrite page_cgroup->mem_cgroup, page_cgroup is
not on LRU or page_cgroup->mem_cgroup is NULL.)We can lose file_mapped accounting information at 5 because FILE_MAPPED
is updated only when mapcount changes 0->1. So we should catch it.BTW, historically, above implemntation comes from migration-failure
of anonymous page. Because we charge both of old page and new page
with mapcount=0, we can't catch
- the page is really freed before remap.
- migration fails but it's freed before remap
or .....corner cases.New migration sequence with memcg is:
1. allocate a new page.
2. mark PageCgroupMigration to the old page.
3. charge against a new page onto the old page's memcg. (here, new page's pc
is marked as PageCgroupUsed.)
4. page migration replaces radix-tree, page table, etc...
5. At remapping, new page's page_cgroup is now makrked as "USED"
We can catch 0->1 event and FILE_MAPPED will be properly updated.And we can catch SWAPOUT event after unlock this and freeing this
page by unmap() can be caught.7. Clear PageCgroupMigration of the old page.
So, FILE_MAPPED will be correctly updated.
Then, for what MIGRATION flag is ?
Without it, at migration failure, we may have to charge old page again
because it may be fully unmapped. "charge" means that we have to dive into
memory reclaim or something complated. So, it's better to avoid
charge it again. Before this patch, __commit_charge() was working for
both of the old/new page and fixed up all. But this technique has some
racy condtion around FILE_MAPPED and SWAPOUT etc...
Now, the kernel use MIGRATION flag and don't uncharge old page until
the end of migration.I hope this change will make memcg's page migration much simpler. This
page migration has caused several troubles. Worth to add a flag for
simplification.Reviewed-by: Daisuke Nishimura
Tested-by: Daisuke Nishimura
Reported-by: Daisuke Nishimura
Signed-off-by: KAMEZAWA Hiroyuki
Cc: Balbir Singh
Cc: Christoph Lameter
Cc: "Kirill A. Shutemov"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Only an out of memory error will cause ret to be set.
Signed-off-by: Phil Carmody
Acked-by: Kirill A. Shutemov
Cc: Balbir Singh
Cc: Daisuke Nishimura
Acked-by: KAMEZAWA Hiroyuki
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The bottom 4 hunks are atomically changing memory to which there are no
aliases as it's freshly allocated, so there's no need to use atomic
operations.The other hunks are just atomic_read and atomic_set, and do not involve
any read-modify-write. The use of atomic_{read,set} doesn't prevent a
read/write or write/write race, so if a race were possible (I'm not saying
one is), then it would still be there even with atomic_set.See:
http://digitalvampire.org/blog/index.php/2007/05/13/atomic-cargo-cults/Signed-off-by: Phil Carmody
Acked-by: Kirill A. Shutemov
Cc: Balbir Singh
Cc: Daisuke Nishimura
Acked-by: KAMEZAWA Hiroyuki
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
It's pointless to try to kill current if select_bad_process() did not find
an eligible task to kill in mem_cgroup_out_of_memory() since it's
guaranteed that current is a member of the memcg that is oom and it is, by
definition, unkillable.Signed-off-by: David Rientjes
Acked-by: KAMEZAWA Hiroyuki
Cc: Balbir Singh
Cc: Li Zefan
Cc: Daisuke Nishimura
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This patch adds support for moving charge of file pages, which include
normal file, tmpfs file and swaps of tmpfs file. It's enabled by setting
bit 1 of /memory.move_charge_at_immigrate.Unlike the case of anonymous pages, file pages(and swaps) in the range
mmapped by the task will be moved even if the task hasn't done page fault,
i.e. they might not be the task's "RSS", but other task's "RSS" that maps
the same file. And mapcount of the page is ignored(the page can be moved
even if page_mapcount(page) > 1). So, conditions that the page/swap
should be met to be moved is that it must be in the range mmapped by the
target task and it must be charged to the old cgroup.[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix warning]
Signed-off-by: Daisuke Nishimura
Acked-by: KAMEZAWA Hiroyuki
Cc: Balbir Singh
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This patch cleans up move charge code by:
- define functions to handle pte for each types, and make
is_target_pte_for_mc() cleaner.- instead of checking the MOVE_CHARGE_TYPE_ANON bit, define a function
that checks the bit.Signed-off-by: Daisuke Nishimura
Acked-by: KAMEZAWA Hiroyuki
Cc: Balbir Singh
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This adds a feature to disable oom-killer for memcg, if disabled, of
course, tasks under memcg will stop.But now, we have oom-notifier for memcg. And the world around memcg is
not under out-of-memory. memcg's out-of-memory just shows memcg hits
limit. Then, administrator or management daemon can recover the situation
by- kill some process
- enlarge limit, add more swap.
- migrate some tasks
- remove file cache on tmps (difficult ?)Unlike oom-killer, you can take enough information before killing tasks.
(by gcore, or, ps etc.)[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: KAMEZAWA Hiroyuki
Cc: Daisuke Nishimura
Cc: Balbir Singh
Cc: Daisuke Nishimura
Cc: David Rientjes
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Considering containers or other resource management softwares in userland,
event notification of OOM in memcg should be implemented. Now, memcg has
"threshold" notifier which uses eventfd, we can make use of it for oom
notification.This patch adds oom notification eventfd callback for memcg. The usage is
very similar to threshold notifier, but control file is memory.oom_control
and no arguments other than eventfd is required.% cgroup_event_notifier /cgroup/A/memory.oom_control dummy
(About cgroup_event_notifier, see Documentation/cgroup/)Signed-off-by: KAMEZAWA Hiroyuki
Cc: Daisuke Nishimura
Cc: Balbir Singh
Cc: Daisuke Nishimura
Cc: David Rientjes
Cc: Davide Libenzi
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
memcg's oom waitqueue is a system-wide wait_queue (for handling
hierarchy.) So, it's better to add custom wake function and do filtering
in wake up path.This patch adds a filtering feature for waking up oom-waiters. Hierarchy
is properly handled.Signed-off-by: KAMEZAWA Hiroyuki
Reviewed-by: Daisuke Nishimura
Cc: Balbir Singh
Cc: Daisuke Nishimura
Cc: David Rientjes
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
27 May, 2010
1 commit
-
I/O errors can happen due to temporary failures, like multipath
errors or losing network contact with the iSCSI server. Because
of that, the VM will retry readpage on the page.However, do_generic_file_read does not clear PG_error. This
causes the system to be unable to actually use the data in the
page cache page, even if the subsequent readpage completes
successfully!The function filemap_fault has had a ClearPageError before
readpage forever. This patch simply adds the same to
do_generic_file_read.Signed-off-by: Jeff Moyer
Signed-off-by: Rik van Riel
Acked-by: Larry Woodman
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds
26 May, 2010
2 commits
-
Slightly rearrange the logic that determines capabilities and vm_flags.
Disable BDI_CAP_MAP_DIRECT in all cases if the device can't support the
protections. Allow private readonly mappings of readonly backing devices.Signed-off-by: Bernd Schmidt
Signed-off-by: Mike Frysinger
Acked-by: David McCullough
Acked-by: Greg Ungerer
Acked-by: Paul Mundt
Acked-by: David Howells
Cc: Hugh Dickins
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The original code called mpol_put(new) while "new" was an ERR_PTR.
Signed-off-by: Dan Carpenter
Cc: Lee Schermerhorn
Cc: KOSAKI Motohiro
Cc: Christoph Lameter
Acked-by: David Rientjes
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
25 May, 2010
7 commits
-
Add global mutex zonelists_mutex to fix the possible race:
CPU0 CPU1 CPU2
(1) zone->present_pages += online_pages;
(2) build_all_zonelists();
(3) alloc_page();
(4) free_page();
(5) build_all_zonelists();
(6) __build_all_zonelists();
(7) zone->pageset = alloc_percpu();In step (3,4), zone->pageset still points to boot_pageset, so bad
things may happen if 2+ nodes are in this state. Even if only 1 node
is accessing the boot_pageset, (3) may still consume too much memory
to fail the memory allocations in step (7).Besides, atomic operation ensures alloc_percpu() in step (7) will never fail
since there is a new fresh memory block added in step(6).[haicheng.li@linux.intel.com: hold zonelists_mutex when build_all_zonelists]
Signed-off-by: Haicheng Li
Signed-off-by: Wu Fengguang
Reviewed-by: Andi Kleen
Cc: Christoph Lameter
Cc: Mel Gorman
Cc: Tejun Heo
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
For each new populated zone of hotadded node, need to update its pagesets
with dynamically allocated per_cpu_pageset struct for all possible CPUs:1) Detach zone->pageset from the shared boot_pageset
at end of __build_all_zonelists().2) Use mutex to protect zone->pageset when it's still
shared in onlined_pages()Otherwises, multiple zones of different nodes would share same boot strapping
boot_pageset for same CPU, which will finally cause below kernel panic:------------[ cut here ]------------
kernel BUG at mm/page_alloc.c:1239!
invalid opcode: 0000 [#1] SMP
...
Call Trace:
[] __alloc_pages_nodemask+0x131/0x7b0
[] alloc_pages_current+0x87/0xd0
[] __page_cache_alloc+0x67/0x70
[] __do_page_cache_readahead+0x120/0x260
[] ra_submit+0x21/0x30
[] ondemand_readahead+0x166/0x2c0
[] page_cache_async_readahead+0x80/0xa0
[] generic_file_aio_read+0x364/0x670
[] nfs_file_read+0xca/0x130
[] do_sync_read+0xfa/0x140
[] vfs_read+0xb5/0x1a0
[] sys_read+0x51/0x80
[] system_call_fastpath+0x16/0x1b
RIP [] get_page_from_freelist+0x883/0x900
RSP
---[ end trace 4bda28328b9990db ][akpm@linux-foundation.org: merge fix]
Signed-off-by: Haicheng Li
Signed-off-by: Wu Fengguang
Reviewed-by: Andi Kleen
Reviewed-by: Christoph Lameter
Cc: Mel Gorman
Cc: Tejun Heo
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
No behavior change here.
Move some of setup_per_cpu_pageset() code into a new function
setup_zone_pageset() that will be useful for memory hotplug.Signed-off-by: Wu Fengguang
Signed-off-by: Haicheng Li
Reviewed-by: Andi Kleen
Reviewed-by: Christoph Lameter
Cc: Mel Gorman
Cc: Tejun Heo
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
In f4112de6b679d84bd9b9681c7504be7bdfb7c7d5 ("mm: introduce
debug_kmap_atomic") I said that debug_kmap_atomic() needs
CONFIG_TRACE_IRQFLAGS_SUPPORT.It was wrong. (I thought irqs_disabled() is only available when the
architecture has CONFIG_TRACE_IRQFLAGS_SUPPORT)Remove the #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT check to enable
kmap_atomic() debugging for the architectures which do not have
CONFIG_TRACE_IRQFLAGS_SUPPORT.Reported-by: Andrew Morton
Signed-off-by: Akinobu Mita
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Enable users to online CPUs even if the CPUs belongs to a numa node which
doesn't have onlined local memory.The zonlists(pg_data_t.node_zonelists[]) of a numa node are created either
in system boot/init period, or at the time of local memory online. For a
numa node without onlined local memory, its zonelists are not initialized
at present. As a result, any memory allocation operations executed by
CPUs within this node will fail. In fact, an out-of-memory error is
triggered when attempt to online CPUs before memory comes to online.This patch tries to create zonelists for such numa nodes, so that the
memory allocation for this node can be fallback'ed to other nodes.[akpm@linux-foundation.org: remove unneeded export]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: minskey guo
Cc: Minchan Kim
Cc: Yasunori Goto
Cc: Andi Kleen
Cc: Christoph Lameter
Cc: Tejun Heo
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
For now, we have global isolation vs. memory control group isolation, do
not allow the reclaim entry function to set an arbitrary page isolation
callback, we do not need that flexibility.And since we already pass around the group descriptor for the memory
control group isolation case, just use it to decide which one of the two
isolator functions to use.The decisions can be merged into nearby branches, so no extra cost there.
In fact, we save the indirect calls.Signed-off-by: Johannes Weiner
Cc: KOSAKI Motohiro
Cc: Mel Gorman
Cc: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This scan control is abused to communicate a return value from
shrink_zones(). Write this idiomatically and remove the knob.Signed-off-by: Johannes Weiner
Reviewed-by: KOSAKI Motohiro
Cc: Mel Gorman
Cc: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
