29 Jun, 2006
1 commit
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Same as with already do with the file operations: keep them in .rodata and
prevents people from doing runtime patching.Signed-off-by: Christoph Hellwig
Cc: Steven French
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
28 Jun, 2006
15 commits
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Runtime debugging functionality for rt-mutexes.
Signed-off-by: Ingo Molnar
Signed-off-by: Thomas Gleixner
Signed-off-by: Arjan van de Ven
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Add debug_check_no_locks_freed(), as a central inline to add
bad-lock-free-debugging functionality to.Signed-off-by: Ingo Molnar
Signed-off-by: Thomas Gleixner
Signed-off-by: Arjan van de Ven
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Make notifier_calls associated with cpu_notifier as __cpuinit.
__cpuinit makes sure that the function is init time only unless
CONFIG_HOTPLUG_CPU is defined.[akpm@osdl.org: section fix]
Signed-off-by: Chandra Seetharaman
Cc: Ashok Raj
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Make notifier_blocks associated with cpu_notifier as __cpuinitdata.
__cpuinitdata makes sure that the data is init time only unless
CONFIG_HOTPLUG_CPU is defined.Signed-off-by: Chandra Seetharaman
Cc: Ashok Raj
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
In 2.6.17, there was a problem with cpu_notifiers and XFS. I provided a
band-aid solution to solve that problem. In the process, i undid all the
changes you both were making to ensure that these notifiers were available
only at init time (unless CONFIG_HOTPLUG_CPU is defined).We deferred the real fix to 2.6.18. Here is a set of patches that fixes the
XFS problem cleanly and makes the cpu notifiers available only at init time
(unless CONFIG_HOTPLUG_CPU is defined).If CONFIG_HOTPLUG_CPU is defined then cpu notifiers are available at run
time.This patch reverts the notifier_call changes made in 2.6.17
Signed-off-by: Chandra Seetharaman
Cc: Ashok Raj
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
generic_file_buffered_write() prefaults in user pages in order to avoid
deadlock on copying from the same page as write goes to.However, it looks like there is a problem when write is vectored:
fault_in_pages_readable brings in current segment or its part (maxlen).
OTOH, filemap_copy_from_user_iovec is called to copy number of bytes
(bytes) which may exceed current segment, so filemap_copy_from_user_iovec
switches to the next segment which is not brought in yet. Pagefault is
generated. That causes the deadlock if pagefault is for the same page
write goes to: page being written is locked and not uptodate, pagefault
will deadlock trying to lock locked page.[akpm@osdl.org: somewhat rewritten]
Cc: Neil Brown
Cc: Martin Schwidefsky
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
locking init cleanups:
- convert " = SPIN_LOCK_UNLOCKED" to spin_lock_init() or DEFINE_SPINLOCK()
- convert rwlocks in a similar mannerthis patch was generated automatically.
Motivation:
- cleanliness
- lockdep needs control of lock initialization, which the open-coded
variants do not give
- it's also useful for -rt and for lock debugging in generalSigned-off-by: Ingo Molnar
Signed-off-by: Arjan van de Ven
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Localize poison values into one header file for better documentation and
easier/quicker debugging and so that the same values won't be used for
multiple purposes.Use these constants in core arch., mm, driver, and fs code.
Signed-off-by: Randy Dunlap
Acked-by: Matt Mackall
Cc: Paul Mackerras
Cc: Benjamin Herrenschmidt
Cc: "David S. Miller"
Cc: Andi Kleen
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
When new node becomes enable by hot-add, new sysfs file must be created for
new node. So, if new node is enabled by add_memory(), register_one_node() is
called to create it. In addition, I386's arch_register_node() and a part of
register_nodes() of powerpc are consolidated to register_one_node() as a
generic_code().This is tested by Tiger4(IPF) with node hot-plug emulation.
Signed-off-by: Keiichiro Tokunaga
Signed-off-by: Yasunori Goto
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Fix "undefined reference to `arch_add_memory'" on sparc64 allmodconfig.
sparc64 doesn't support memory hotplug. But we want it to support
sparsemem.Signed-off-by: Yasunori Goto
Cc: "David S. Miller"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This patch allows hot-add memory which is not aligned to section.
Now, hot-added memory has to be aligned to section size. Considering big
section sized archs, this is not useful.When hot-added memory is registerd as iomem resoruce by iomem resource
patch, we can make use of that information to detect valid memory range.Note: With this, not-aligned memory can be registerd. To allow hot-add
memory with holes, we have to do more work around add_memory().
(It doesn't allows add memory to already existing mem section.)Signed-off-by: KAMEZAWA Hiroyuki
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Register hot-added memory to iomem_resource. With this, /proc/iomem can
show hot-added memory.Note: kdump uses /proc/iomem to catch memory range when it is installed.
So, kdump should be re-installed after /proc/iomem change.Signed-off-by: KAMEZAWA Hiroyuki
Cc: Vivek Goyal
Cc: Greg KH
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Add node-hot-add support to add_memory().
node hotadd uses this sequence.
1. allocate pgdat.
2. refresh NODE_DATA()
3. call free_area_init_node() to initialize
4. create sysfs entry
5. add memory (old add_memory())
6. set node online
7. run kswapd for new node.
(8). update zonelist after pages are onlined. (This is already merged in -mm
due to update phase is difference.)Note:
To make common function as much as possible,
there is 2 changes from v2.
- The old add_memory(), which is defiend by each archs,
is renamed to arch_add_memory(). New add_memory becomes
caller of arch dependent function as a common code.- This patch changes add_memory()'s interface
From: add_memory(start, end)
TO : add_memory(nid, start, end).
It was cause of similar code that finding node id from
physical address is inside of old add_memory() on each arch.In addition, acpi memory hotplug driver can find node id easier.
In v2, it must walk DSDT'S _CRS by matching physical address to
get the handle of its memory device, then get _PXM and node id.
Because input is just physical address.
However, in v3, the acpi driver can use handle to get _PXM and node id
for the new memory device. It can pass just node id to add_memory().Fix interface of arch_add_memory() is in next patche.
Signed-off-by: Yasunori Goto
Signed-off-by: KAMEZAWA Hiroyuki
Cc: Dave Hansen
Cc: "Brown, Len"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
When node is hot-added, kswapd for the node should start. This export kswapd
start function as kswapd_run() to use at add_memory().[akpm@osdl.org: daemonize() isn't needed when using the kthread API]
Signed-off-by: Yasunori Goto
Signed-off-by: KAMEZAWA Hiroyuki
Cc: Dave Hansen
Cc: "Brown, Len"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Change the name of old add_memory() to arch_add_memory. And use node id to
get pgdat for the node at NODE_DATA().Note: Powerpc's old add_memory() is defined as __devinit. However,
add_memory() is usually called only after bootup.
I suppose it may be redundant. But, I'm not well known about powerpc.
So, I keep it. (But, __meminit is better at least.)Signed-off-by: Yasunori Goto
Cc: Dave Hansen
Cc: "Brown, Len"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
27 Jun, 2006
4 commits
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* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial:
typo fixes
Clean up 'inline is not at beginning' warnings for usb storage
Storage class should be first
i386: Trivial typo fixes
ixj: make ixj_set_tone_off() static
spelling fixes
fix paniced->panicked typos
Spelling fixes for Documentation/atomic_ops.txt
move acknowledgment for Mark Adler to CREDITS
remove the bouncing email address of David Campbell -
Every inode in /proc holds a reference to a struct task_struct. If a
directory or file is opened and remains open after the the task exits this
pinning continues. With 8K stacks on a 32bit machine the amount pinned per
file descriptor is about 10K.Normally I would figure a reasonable per user process limit is about 100
processes. With 80 processes, with a 1000 file descriptors each I can trigger
the 00M killer on a 32bit kernel, because I have pinned about 800MB of useless
data.This patch replaces the struct task_struct pointer with a pointer to a struct
task_ref which has a struct task_struct pointer. The so the pinning of dead
tasks does not happen.The code now has to contend with the fact that the task may now exit at any
time. Which is a little but not muh more complicated.With this change it takes about 1000 processes each opening up 1000 file
descriptors before I can trigger the OOM killer. Much better.[mlp@google.com: task_mmu small fixes]
Signed-off-by: Eric W. Biederman
Cc: Trond Myklebust
Cc: Paul Jackson
Cc: Oleg Nesterov
Cc: Albert Cahalan
Signed-off-by: Prasanna Meda
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This patch converts the combination of list_del(A) and list_add(A, B) to
list_move(A, B).Cc: Greg Kroah-Hartman
Cc: Ram Pai
Signed-off-by: Akinobu Mita
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
acquired (aquired)
contiguous (contigious)
successful (succesful, succesfull)
surprise (suprise)
whether (weather)
some other misspellingsSigned-off-by: Andreas Mohr
Signed-off-by: Adrian Bunk
26 Jun, 2006
9 commits
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* git://git.linux-nfs.org/pub/linux/nfs-2.6: (51 commits)
nfs: remove nfs_put_link()
nfs-build-fix-99
git-nfs-build-fixes
Merge branch 'odirect'
NFS: alloc nfs_read/write_data as direct I/O is scheduled
NFS: Eliminate nfs_get_user_pages()
NFS: refactor nfs_direct_free_user_pages
NFS: remove user_addr, user_count, and pos from nfs_direct_req
NFS: "open code" the NFS direct write rescheduler
NFS: Separate functions for counting outstanding NFS direct I/Os
NLM: Fix reclaim races
NLM: sem to mutex conversion
locks.c: add the fl_owner to nlm_compare_locks
NFS: Display the chosen RPCSEC_GSS security flavour in /proc/mounts
NFS: Split fs/nfs/inode.c
NFS: Fix typo in nfs_do_clone_mount()
NFS: Fix compile errors introduced by referrals patches
NFSv4: Ensure that referral mounts bind to a reserved port
NFSv4: A root pathname is sent as a zero component4
NFSv4: Follow a referral
... -
Backoff readahead size exponentially on I/O error.
Michael Tokarev described the problem as:
[QUOTE]
Suppose there's a CD-rom with a scratch/etc, one sector is unreadable.
In order to "fix" it, one have to read it and write to another CD-rom,
or something.. or just ignore the error (if it's just a skip in a video
stream). Let's assume the unreadable block is number U.But current behavior is just insane. An application requests block
number N, which is before U. Kernel tries to read-ahead blocks N..U.
Cdrom drive tries to read it, re-read it.. for some time. Finally,
when all the N..U-1 blocks are read, kernel returns block number N
(as requested) to an application, successefully.Now an app requests block number N+1, and kernel tries to read
blocks N+1..U+1. Retrying again as in previous step.And so on, up to when an app requests block number U-1. And when,
finally, it requests block U, it receives read error.So, kernel currentry tries to re-read the same failing block as
many times as the current readahead value (256 (times?) by default).This whole process already killed my cdrom drive (I posted about it
to LKML several months ago) - literally, the drive has fried, and
does not work anymore. Ofcourse that problem was a bug in firmware
(or whatever) of the drive *too*, but.. main problem with that is
current readahead logic as described above.
[/QUOTE]Which was confirmed by Jens Axboe :
[QUOTE]
For ide-cd, it tends do only end the first part of the request on a
medium error. So you may see a lot of repeats :/
[/QUOTE]With this patch, retries are expected to be reduced from, say, 256, to 5.
[akpm@osdl.org: cleanups]
Signed-off-by: Wu Fengguang
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Put short function description for read_cache_pages() on one line as needed
by kernel-doc.Signed-off-by: Randy Dunlap
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The problem is that when we write to a file, the copy from userspace to
pagecache is first done with preemption disabled, so if the source address is
not immediately available the copy fails *and* *zeros* *the* *destination*.This is a problem because a concurrent read (which admittedly is an odd thing
to do) might see zeros rather that was there before the write, or what was
there after, or some mixture of the two (any of these being a reasonable thing
to see).If the copy did fail, it will immediately be retried with preemption
re-enabled so any transient problem with accessing the source won't cause an
error.The first copying does not need to zero any uncopied bytes, and doing so
causes the problem. It uses copy_from_user_atomic rather than copy_from_user
so the simple expedient is to change copy_from_user_atomic to *not* zero out
bytes on failure.The first of these two patches prepares for the change by fixing two places
which assume copy_from_user_atomic does zero the tail. The two usages are
very similar pieces of code which copy from a userspace iovec into one or more
page-cache pages. These are changed to remove the assumption.The second patch changes __copy_from_user_inatomic* to not zero the tail.
Once these are accepted, I will look at similar patches of other architectures
where this is important (ppc, mips and sparc being the ones I can find).This patch:
There is a problem with __copy_from_user_inatomic zeroing the tail of the
buffer in the case of an error. As it is called in atomic context, the error
may be transient, so it results in zeros being written where maybe they
shouldn't be.In the usage in filemap, this opens a window for a well timed read to see data
(zeros) which is not consistent with any ordering of reads and writes.Most cases where __copy_from_user_inatomic is called, a failure results in
__copy_from_user being called immediately. As long as the latter zeros the
tail, the former doesn't need to. However in *copy_from_user_iovec
implementations (in both filemap and ntfs/file), it is assumed that
copy_from_user_inatomic will zero the tail.This patch removes that assumption, so that after this patch it will
be safe for copy_from_user_inatomic to not zero the tail.This patch also adds some commentary to filemap.h and asm-i386/uaccess.h.
After this patch, all architectures that might disable preempt when
kmap_atomic is called need to have their __copy_from_user_inatomic* "fixed".
This includes
- powerpc
- i386
- mips
- sparcSigned-off-by: Neil Brown
Cc: David Howells
Cc: Anton Altaparmakov
Cc: Benjamin Herrenschmidt
Cc: Paul Mackerras
Cc: Ralf Baechle
Cc: William Lee Irwin III
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This is redundant with check in wakeup_kswapd.
Signed-off-by: Chris Wright
Acked-by: Paul Jackson
Acked-by: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
pdflush is carefully designed to ensure that all wakeups have some
corresponding work to do - if a woken-up pdflush thread discovers that it
hasn't been given any work to do then this is considered an error.That all broke when swsusp came along - because a timer-delivered wakeup to a
frozen pdflush thread will just get lost. This causes the pdflush thread to
get lost as well: the writeback timer is supposed to be re-armed by pdflush in
process context, but pdflush doesn't execute the callout which does this.Fix that up by ignoring the return value from try_to_freeze(): jsut proceed,
see if we have any work pending and only go back to sleep if that is not the
case.Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Hugh clarified the role of VM_LOCKED. So we can now implement page
migration for mlocked pages.Allow the migration of mlocked pages. This means that try_to_unmap must
unmap mlocked pages in the migration case.Signed-off-by: Christoph Lameter
Acked-by: Hugh Dickins
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Hooks for calling vma specific migration functions
With this patch a vma may define a vma->vm_ops->migrate function. That
function may perform page migration on its own (some vmas may not contain page
structs and therefore cannot be handled by regular page migration. Pages in a
vma may require special preparatory treatment before migration is possible
etc) . Only mmap_sem is held when the migration function is called. The
migrate() function gets passed two sets of nodemasks describing the source and
the target of the migration. The flags parameter either containsMPOL_MF_MOVE which means that only pages used exclusively by
the specified mm should be movedor
MPOL_MF_MOVE_ALL which means that pages shared with other processes
should also be moved.The migration function returns 0 on success or an error condition. An error
condition will prevent regular page migration from occurring.On its own this patch cannot be included since there are no users for this
functionality. But it seems that the uncached allocator will need this
functionality at some point.Signed-off-by: Christoph Lameter
Cc: Hugh Dickins
Cc: Andi Kleen
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
AOP_TRUNCATED_PAGE victims in read_pages() belong in the LRU
Nick Piggin rightly pointed out that the introduction of AOP_TRUNCATED_PAGE
to read_pages() was wrong to leave A_T_P victim pages in the page cache but
not put them in the LRU. Failing to do so hid them from the VM.A_T_P just means that the aop method unlocked the page rather than
performing IO. It would be very rare that the page was truncated between
the unlock and testing A_T_P. So we leave the pages in the LRU for likely
reuse soon rather than backing them back out of the page cache. We do this
by matching the behaviour before the A_T_P introduction which added pages
to the LRU regardless of what ->readpage() did.This doesn't include the unrelated cleanup in Nick's initial fix which
changed read_pages() to return void to match its only caller's behaviour of
ignoring errors.Signed-off-by: Nick Piggin
Signed-off-by: Zach Brown
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
25 Jun, 2006
1 commit
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Conflicts:
fs/nfs/inode.c
fs/super.cFix conflicts between patch 'NFS: Split fs/nfs/inode.c' and patch
'VFS: Permit filesystem to override root dentry on mount'
23 Jun, 2006
10 commits
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A process flag to indicate whether we are doing sync io is incredibly
ugly. It also causes performance problems when one does a lot of async
io and then proceeds to sync it. Part of the io will go out as async,
and the other part as sync. This causes a disconnect between the
previously submitted io and the synced io. For io schedulers such as CFQ,
this will cause us lost merges and suboptimal behaviour in scheduling.Remove PF_SYNCWRITE completely from the fsync/msync paths, and let
the O_DIRECT path just directly indicate that the writes are sync
by using WRITE_SYNC instead.Signed-off-by: Jens Axboe
-
Signed-off-by: Eric Sesterhenn
Signed-off-by: Alexey Dobriyan
Cc: Bartlomiej Zolnierkiewicz
Cc: Alan Cox
Cc: James Bottomley
Acked-by: "Salyzyn, Mark"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
If invalidate_mapping_pages is called to invalidate a very large mapping
(e.g. a very large block device) and if the only active page in that
device is near the end (or at least, at a very large index), such as, say,
the superblock of an md array, and if that page happens to be locked when
invalidate_mapping_pages is called, thenpagevec_lookup will return this page and
as it is locked, 'next' will be incremented and pagevec_lookup
will be called again. and again. and again.
while we count from 0 upto a very large number.We should really always set 'next' to 'page->index+1' before going around
the loop again, not just if the page isn't locked.Cc: "Steinar H. Gunderson"
Signed-off-by: Neil Brown
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
- Move percpu_counter routines from mm/swap.c to lib/percpu_counter.c
Signed-off-by: Ravikiran Thirumalai
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Add read_mapping_page() which is used for callers that pass
mapping->a_ops->readpage as the filler for read_cache_page. This removes
some duplication from filesystem code.Signed-off-by: Pekka Enberg
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Use the x86 cache-bypassing copy instructions for copy_from_user().
Some performance data are
Total of GLOBAL_POWER_EVENTS (CPU cycle samples)
2.6.12.4.orig 1921587
2.6.12.4.nt 1599424
1599424/1921587=83.23% (16.77% reduction)BSQ_CACHE_REFERENCE (L3 cache miss)
2.6.12.4.orig 57427
2.6.12.4.nt 20858
20858/57427=36.32% (63.7% reduction)L3 cache miss reduction of __copy_from_user_ll
samples %
37408 65.1412 vmlinux __copy_from_user_ll
23 0.1103 vmlinux __copy_user_zeroing_intel_nocache
23/37408=0.061% (99.94% reduction)Top 5 of 2.6.12.4.nt
Counted GLOBAL_POWER_EVENTS events (time during which processor is not stopped) with a unit mask of 0x01 (mandatory) count 100000
samples % app name symbol name
128392 8.0274 vmlinux __copy_user_zeroing_intel_nocache
64206 4.0143 vmlinux journal_add_journal_head
59746 3.7355 vmlinux do_get_write_access
47674 2.9807 vmlinux journal_put_journal_head
46021 2.8774 vmlinux journal_dirty_metadata
pattern9-0-cpu4-0-09011728/summary.outCounted BSQ_CACHE_REFERENCE events (cache references seen by the bus unit) with a unit mask of 0x3f (multiple flags) count 3000
samples % app name symbol name
69755 4.2861 vmlinux __copy_user_zeroing_intel_nocache
55685 3.4215 vmlinux journal_add_journal_head
52371 3.2179 vmlinux __find_get_block
45504 2.7960 vmlinux journal_put_journal_head
36005 2.2123 vmlinux journal_stop
pattern9-0-cpu4-0-09011744/summary.outCounted BSQ_CACHE_REFERENCE events (cache references seen by the bus unit) with a unit mask of 0x200 (read 3rd level cache miss) count 3000
samples % app name symbol name
1147 5.4994 vmlinux journal_add_journal_head
881 4.2240 vmlinux journal_dirty_data
872 4.1809 vmlinux blk_rq_map_sg
734 3.5192 vmlinux journal_commit_transaction
617 2.9582 vmlinux radix_tree_delete
pattern9-0-cpu4-0-09011731/summary.outiozone results are
original 2.6.12.4 CPU time = 207.768 sec
cache aware CPU time = 184.783 sec
(three times run)
184.783/207.768=88.94% (11.06% reduction)original:
pattern9-0-cpu4-0-08191720/iozone.out: CPU Utilization: Wall time 45.997 CPU time 64.527 CPU utilization 140.28 %
pattern9-0-cpu4-0-08191741/iozone.out: CPU Utilization: Wall time 46.878 CPU time 71.933 CPU utilization 153.45 %
pattern9-0-cpu4-0-08191743/iozone.out: CPU Utilization: Wall time 45.152 CPU time 71.308 CPU utilization 157.93 %cache awre:
pattern9-0-cpu4-0-09011728/iozone.out: CPU Utilization: Wall time 44.842 CPU time 62.465 CPU utilization 139.30 %
pattern9-0-cpu4-0-09011731/iozone.out: CPU Utilization: Wall time 44.718 CPU time 59.273 CPU utilization 132.55 %
pattern9-0-cpu4-0-09011744/iozone.out: CPU Utilization: Wall time 44.367 CPU time 63.045 CPU utilization 142.10 %Signed-off-by: Hiro Yoshioka
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This patch inserts security_task_movememory hook calls into memory management
code to enable security modules to mediate this operation between tasks.Since the last posting, the hook has been renamed following feedback from
Christoph Lameter.Signed-off-by: David Quigley
Acked-by: Stephen Smalley
Signed-off-by: James Morris
Cc: Andi Kleen
Acked-by: Christoph Lameter
Acked-by: Chris Wright
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
move_pages() is used to move individual pages of a process. The function can
be used to determine the location of pages and to move them onto the desired
node. move_pages() returns status information for each page.long move_pages(pid, number_of_pages_to_move,
addresses_of_pages[],
nodes[] or NULL,
status[],
flags);The addresses of pages is an array of void * pointing to the
pages to be moved.The nodes array contains the node numbers that the pages should be moved
to. If a NULL is passed instead of an array then no pages are moved but
the status array is updated. The status request may be used to determine
the page state before issuing another move_pages() to move pages.The status array will contain the state of all individual page migration
attempts when the function terminates. The status array is only valid if
move_pages() completed successfullly.Possible page states in status[]:
0..MAX_NUMNODES The page is now on the indicated node.
-ENOENT Page is not present
-EACCES Page is mapped by multiple processes and can only
be moved if MPOL_MF_MOVE_ALL is specified.-EPERM The page has been mlocked by a process/driver and
cannot be moved.-EBUSY Page is busy and cannot be moved. Try again later.
-EFAULT Invalid address (no VMA or zero page).
-ENOMEM Unable to allocate memory on target node.
-EIO Unable to write back page. The page must be written
back in order to move it since the page is dirty and the
filesystem does not provide a migration function that
would allow the moving of dirty pages.-EINVAL A dirty page cannot be moved. The filesystem does not provide
a migration function and has no ability to write back pages.The flags parameter indicates what types of pages to move:
MPOL_MF_MOVE Move pages that are only mapped by the process.
MPOL_MF_MOVE_ALL Also move pages that are mapped by multiple processes.
Requires sufficient capabilities.Possible return codes from move_pages()
-ENOENT No pages found that would require moving. All pages
are either already on the target node, not present, had an
invalid address or could not be moved because they were
mapped by multiple processes.-EINVAL Flags other than MPOL_MF_MOVE(_ALL) specified or an attempt
to migrate pages in a kernel thread.-EPERM MPOL_MF_MOVE_ALL specified without sufficient priviledges.
or an attempt to move a process belonging to another user.-EACCES One of the target nodes is not allowed by the current cpuset.
-ENODEV One of the target nodes is not online.
-ESRCH Process does not exist.
-E2BIG Too many pages to move.
-ENOMEM Not enough memory to allocate control array.
-EFAULT Parameters could not be accessed.
A test program for move_pages() may be found with the patches
on ftp.kernel.org:/pub/linux/kernel/people/christoph/pmig/patches-2.6.17-rc4-mm3From: Christoph Lameter
Detailed results for sys_move_pages()
Pass a pointer to an integer to get_new_page() that may be used to
indicate where the completion status of a migration operation should be
placed. This allows sys_move_pags() to report back exactly what happened to
each page.Wish there would be a better way to do this. Looks a bit hacky.
Signed-off-by: Christoph Lameter
Cc: Hugh Dickins
Cc: Jes Sorensen
Cc: KAMEZAWA Hiroyuki
Cc: Lee Schermerhorn
Cc: Andi Kleen
Cc: Michael Kerrisk
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Instead of passing a list of new pages, pass a function to allocate a new
page. This allows the correct placement of MPOL_INTERLEAVE pages during page
migration. It also further simplifies the callers of migrate pages.
migrate_pages() becomes similar to migrate_pages_to() so drop
migrate_pages_to(). The batching of new page allocations becomes unnecessary.Signed-off-by: Christoph Lameter
Cc: Hugh Dickins
Cc: Jes Sorensen
Cc: KAMEZAWA Hiroyuki
Cc: Lee Schermerhorn
Cc: Andi Kleen
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Do not leave pages on the lists passed to migrate_pages(). Seems that we will
not need any postprocessing of pages. This will simplify the handling of
pages by the callers of migrate_pages().Signed-off-by: Christoph Lameter
Cc: Hugh Dickins
Cc: Jes Sorensen
Cc: KAMEZAWA Hiroyuki
Cc: Lee Schermerhorn
Cc: Andi Kleen
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
