firefly-linux-kernel-4.4.55.git
13 years agoMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris...
Linus Torvalds [Thu, 28 Jul 2011 02:26:38 +0000 (19:26 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/jmorris/security-testing-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6: (54 commits)
  tpm_nsc: Fix bug when loading multiple TPM drivers
  tpm: Move tpm_tis_reenable_interrupts out of CONFIG_PNP block
  tpm: Fix compilation warning when CONFIG_PNP is not defined
  TOMOYO: Update kernel-doc.
  tpm: Fix a typo
  tpm_tis: Probing function for Intel iTPM bug
  tpm_tis: Fix the probing for interrupts
  tpm_tis: Delay ACPI S3 suspend while the TPM is busy
  tpm_tis: Re-enable interrupts upon (S3) resume
  tpm: Fix display of data in pubek sysfs entry
  tpm_tis: Add timeouts sysfs entry
  tpm: Adjust interface timeouts if they are too small
  tpm: Use interface timeouts returned from the TPM
  tpm_tis: Introduce durations sysfs entry
  tpm: Adjust the durations if they are too small
  tpm: Use durations returned from TPM
  TOMOYO: Enable conditional ACL.
  TOMOYO: Allow using argv[]/envp[] of execve() as conditions.
  TOMOYO: Allow using executable's realpath and symlink's target as conditions.
  TOMOYO: Allow using owner/group etc. of file objects as conditions.
  ...

Fix up trivial conflict in security/tomoyo/realpath.c

13 years agoMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs...
Linus Torvalds [Wed, 27 Jul 2011 23:43:52 +0000 (16:43 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/mason/btrfs-unstable

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: make sure reserve_metadata_bytes doesn't leak out strange errors
  Btrfs: use the commit_root for reading free_space_inode crcs
  Btrfs: reduce extent_state lock contention for metadata
  Btrfs: remove lockdep magic from btrfs_next_leaf
  Btrfs: make a lockdep class for each root
  Btrfs: switch the btrfs tree locks to reader/writer
  Btrfs: fix deadlock when throttling transactions
  Btrfs: stop using highmem for extent_buffers
  Btrfs: fix BUG_ON() caused by ENOSPC when relocating space
  Btrfs: tag pages for writeback in sync
  Btrfs: fix enospc problems with delalloc
  Btrfs: don't flush delalloc arbitrarily
  Btrfs: use find_or_create_page instead of grab_cache_page
  Btrfs: use a worker thread to do caching
  Btrfs: fix how we merge extent states and deal with cached states
  Btrfs: use the normal checksumming infrastructure for free space cache
  Btrfs: serialize flushers in reserve_metadata_bytes
  Btrfs: do transaction space reservation before joining the transaction
  Btrfs: try to only do one btrfs_search_slot in do_setxattr

13 years agoMerge branch 'for-linus' of git://oss.sgi.com/xfs/xfs
Linus Torvalds [Wed, 27 Jul 2011 20:41:51 +0000 (13:41 -0700)]
Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfs

* 'for-linus' of git://oss.sgi.com/xfs/xfs:
  xfs: optimize the negative xattr caching
  xfs: prevent against ioend livelocks in xfs_file_fsync
  xfs: flag all buffers as metadata
  xfs: encapsulate a block of debug code

13 years agoMerge branch 'nfs-for-3.1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Linus Torvalds [Wed, 27 Jul 2011 20:23:02 +0000 (13:23 -0700)]
Merge branch 'nfs-for-3.1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

* 'nfs-for-3.1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (44 commits)
  NFSv4: Don't use the delegation->inode in nfs_mark_return_delegation()
  nfs: don't use d_move in nfs_async_rename_done
  RDMA: Increasing RPCRDMA_MAX_DATA_SEGS
  SUNRPC: Replace xprt->resend and xprt->sending with a priority queue
  SUNRPC: Allow caller of rpc_sleep_on() to select priority levels
  SUNRPC: Support dynamic slot allocation for TCP connections
  SUNRPC: Clean up the slot table allocation
  SUNRPC: Initalise the struct xprt upon allocation
  SUNRPC: Ensure that we grab the XPRT_LOCK before calling xprt_alloc_slot
  pnfs: simplify pnfs files module autoloading
  nfs: document nfsv4 sillyrename issues
  NFS: Convert nfs4_set_ds_client to EXPORT_SYMBOL_GPL
  SUNRPC: Convert the backchannel exports to EXPORT_SYMBOL_GPL
  SUNRPC: sunrpc should not explicitly depend on NFS config options
  NFS: Clean up - simplify the switch to read/write-through-MDS
  NFS: Move the pnfs write code into pnfs.c
  NFS: Move the pnfs read code into pnfs.c
  NFS: Allow the nfs_pageio_descriptor to signal that a re-coalesce is needed
  NFS: Use the nfs_pageio_descriptor->pg_bsize in the read/write request
  NFS: Cache rpc_ops in struct nfs_pageio_descriptor
  ...

13 years agoMerge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target...
Linus Torvalds [Wed, 27 Jul 2011 20:21:40 +0000 (13:21 -0700)]
Merge branch 'for-next' of git://git./linux/kernel/git/nab/target-pending

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  target: Convert to DIV_ROUND_UP_SECTOR_T usage for sectors / dev_max_sectors
  kernel.h: Add DIV_ROUND_UP_ULL and DIV_ROUND_UP_SECTOR_T macro usage
  iscsi-target: Add iSCSI fabric support for target v4.1
  iscsi: Add Serial Number Arithmetic LT and GT into iscsi_proto.h
  iscsi: Use struct scsi_lun in iscsi structs instead of u8[8]
  iscsi: Resolve iscsi_proto.h naming conflicts with drivers/target/iscsi

13 years agoMerge branch 'integration' into for-linus
Chris Mason [Wed, 27 Jul 2011 20:13:10 +0000 (16:13 -0400)]
Merge branch 'integration' into for-linus

13 years agoBtrfs: make sure reserve_metadata_bytes doesn't leak out strange errors
Chris Mason [Wed, 27 Jul 2011 19:57:44 +0000 (15:57 -0400)]
Btrfs: make sure reserve_metadata_bytes doesn't leak out strange errors

The btrfs transaction code will return any errors that come from
reserve_metadata_bytes.  We need to make sure we don't return funny
things like 1 or EAGAIN.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
13 years agosignals: sys_ssetmask/sys_rt_sigsuspend should use set_current_blocked()
Oleg Nesterov [Wed, 27 Jul 2011 19:49:44 +0000 (12:49 -0700)]
signals: sys_ssetmask/sys_rt_sigsuspend should use set_current_blocked()

sys_ssetmask(), sys_rt_sigsuspend() and compat_sys_rt_sigsuspend()
change ->blocked directly.  This is not correct, see the changelog in
e6fa16ab "signal: sigprocmask() should do retarget_shared_pending()"

Change them to use set_current_blocked().

Another change is that now we are doing ->saved_sigmask = ->blocked
lockless, it doesn't make any sense to do this under ->siglock.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Matt Fleming <matt.fleming@linux.intel.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agosparc: rename atomic_add_unless
Stephen Rothwell [Wed, 27 Jul 2011 19:49:44 +0000 (12:49 -0700)]
sparc: rename atomic_add_unless

Should have been done in commit 1af08a1407f4 ("This is in preparation
for more generic atomic").

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Arun Sharma <asharma@fb.com>
Cc: David Miller <davem@davemloft.net>
Cc: "Hans-Christian Egtvedt" <hans-christian.egtvedt@atmel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoproc: make struct proc_dir_entry::name a terminal array rather than a pointer
David Howells [Wed, 27 Jul 2011 18:47:03 +0000 (21:47 +0300)]
proc: make struct proc_dir_entry::name a terminal array rather than a pointer

Since __proc_create() appends the name it is given to the end of the PDE
structure that it allocates, there isn't a need to store a name pointer.
Instead we can just replace the name pointer with a terminal char array of
_unspecified_ length.  The compiler will simply append the string to statically
defined variables of PDE type overlapping any hole at the end of the structure
and, unlike specifying an explicitly _zero_ length array, won't give a warning
if you try to statically initialise it with a string of more than zero length.

Also, whilst we're at it:

 (1) Move namelen to end just prior to name and reduce it to a single byte
     (name shouldn't be longer than NAME_MAX).

 (2) Move pde_unload_lock two places further on so that if it's four bytes in
     size on a 64-bit machine, it won't cause an unused hole in the PDE struct.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoBtrfs: use the commit_root for reading free_space_inode crcs
Chris Mason [Tue, 26 Jul 2011 19:35:09 +0000 (15:35 -0400)]
Btrfs: use the commit_root for reading free_space_inode crcs

Now that we are using regular file crcs for the free space cache,
we can deadlock if we try to read the free_space_inode while we are
updating the crc tree.

This commit fixes things by using the commit_root to read the crcs.  This is
safe because we the free space cache file would already be loaded if
that block group had been changed in the current transaction.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
13 years agoBtrfs: reduce extent_state lock contention for metadata
Chris Mason [Mon, 25 Jul 2011 10:50:50 +0000 (06:50 -0400)]
Btrfs: reduce extent_state lock contention for metadata

For metadata buffers that don't straddle pages (all of them), btrfs
can safely use the page uptodate bits and extent_buffer uptodate bit
instead of needing to use the extent_state tree.

This greatly reduces contention on the state tree lock.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
13 years agoBtrfs: remove lockdep magic from btrfs_next_leaf
Chris Mason [Tue, 26 Jul 2011 20:01:59 +0000 (16:01 -0400)]
Btrfs: remove lockdep magic from btrfs_next_leaf

Before the reader/writer locks, btrfs_next_leaf needed to keep
the path blocking to avoid making lockdep upset.

Now that btrfs_next_leaf only takes read locks, this isn't required.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
13 years agoBtrfs: make a lockdep class for each root
Chris Mason [Tue, 26 Jul 2011 20:11:19 +0000 (16:11 -0400)]
Btrfs: make a lockdep class for each root

This patch was originally from Tejun Heo.  lockdep complains about the btrfs
locking because we sometimes take btree locks from two different trees at the
same time.  The current classes are based only on level in the btree, which
isn't enough information for lockdep to figure out if the lock is safe.

This patch makes a class for each type of tree, and lumps all the FS trees that
actually have files and directories into the same class.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
13 years agoBtrfs: switch the btrfs tree locks to reader/writer
Chris Mason [Sat, 16 Jul 2011 19:23:14 +0000 (15:23 -0400)]
Btrfs: switch the btrfs tree locks to reader/writer

The btrfs metadata btree is the source of significant
lock contention, especially in the root node.   This
commit changes our locking to use a reader/writer
lock.

The lock is built on top of rw spinlocks, and it
extends the lock tracking to remember if we have a
read lock or a write lock when we go to blocking.  Atomics
count the number of blocking readers or writers at any
given time.

It removes all of the adaptive spinning from the old code
and uses only the spinning/blocking hints inside of btrfs
to decide when it should continue spinning.

In read heavy workloads this is dramatically faster.  In write
heavy workloads we're still faster because of less contention
on the root node lock.

We suffer slightly in dbench because we schedule more often
during write locks, but all other benchmarks so far are improved.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
13 years agoBtrfs: fix deadlock when throttling transactions
Josef Bacik [Sun, 24 Jul 2011 19:45:34 +0000 (15:45 -0400)]
Btrfs: fix deadlock when throttling transactions

Hit this nice little deadlock.  What happens is this

__btrfs_end_transaction with throttle set, --use_count so it equals 0
  btrfs_commit_transaction
    <somebody else actually manages to start the commit>
    btrfs_end_transaction --use_count so now its -1 <== BAD
      we just return and wait on the transaction

This is bad because we just return after our use_count is -1 and don't let go
of our num_writer count on the transaction, so the guy committing the
transaction just sits there forever.  Fix this by inc'ing our use_count if we're
going to call commit_transaction so that if we call btrfs_end_transaction it's
valid.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
13 years agoBtrfs: stop using highmem for extent_buffers
Chris Mason [Tue, 19 Jul 2011 16:04:14 +0000 (12:04 -0400)]
Btrfs: stop using highmem for extent_buffers

The extent_buffers have a very complex interface where
we use HIGHMEM for metadata and try to cache a kmap mapping
to access the memory.

The next commit adds reader/writer locks, and concurrent use
of this kmap cache would make it even more complex.

This commit drops the ability to use HIGHMEM with extent buffers,
and rips out all of the related code.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
13 years agoBtrfs: fix BUG_ON() caused by ENOSPC when relocating space
Miao Xie [Fri, 15 Jul 2011 10:34:36 +0000 (10:34 +0000)]
Btrfs: fix BUG_ON() caused by ENOSPC when relocating space

When we balanced the chunks across the devices, BUG_ON() in
__finish_chunk_alloc() was triggered.

------------[ cut here ]------------
kernel BUG at fs/btrfs/volumes.c:2568!
[SNIP]
Call Trace:
 [<ffffffffa049525e>] btrfs_alloc_chunk+0x8e/0xa0 [btrfs]
 [<ffffffffa04546b0>] do_chunk_alloc+0x330/0x3a0 [btrfs]
 [<ffffffffa045c654>] btrfs_reserve_extent+0xb4/0x1f0 [btrfs]
 [<ffffffffa045c86b>] btrfs_alloc_free_block+0xdb/0x350 [btrfs]
 [<ffffffffa048a8d8>] ? read_extent_buffer+0xd8/0x1d0 [btrfs]
 [<ffffffffa04476fd>] __btrfs_cow_block+0x14d/0x5e0 [btrfs]
 [<ffffffffa044660d>] ? read_block_for_search+0x14d/0x4d0 [btrfs]
 [<ffffffffa0447c9b>] btrfs_cow_block+0x10b/0x240 [btrfs]
 [<ffffffffa044dd5e>] btrfs_search_slot+0x49e/0x7a0 [btrfs]
 [<ffffffffa044f07d>] btrfs_insert_empty_items+0x8d/0xf0 [btrfs]
 [<ffffffffa045e973>] insert_with_overflow+0x43/0x110 [btrfs]
 [<ffffffffa045eb0d>] btrfs_insert_dir_item+0xcd/0x1f0 [btrfs]
 [<ffffffffa0489bd0>] ? map_extent_buffer+0xb0/0xc0 [btrfs]
 [<ffffffff812276ad>] ? rb_insert_color+0x9d/0x160
 [<ffffffffa046cc40>] ? inode_tree_add+0xf0/0x150 [btrfs]
 [<ffffffffa0474801>] btrfs_add_link+0xc1/0x1c0 [btrfs]
 [<ffffffff811dacac>] ? security_inode_init_security+0x1c/0x30
 [<ffffffffa04a28aa>] ? btrfs_init_acl+0x4a/0x180 [btrfs]
 [<ffffffffa047492f>] btrfs_add_nondir+0x2f/0x70 [btrfs]
 [<ffffffffa046af16>] ? btrfs_init_inode_security+0x46/0x60 [btrfs]
 [<ffffffffa0474ac0>] btrfs_create+0x150/0x1d0 [btrfs]
 [<ffffffff81159c63>] ? generic_permission+0x23/0xb0
 [<ffffffff8115b415>] vfs_create+0xa5/0xc0
 [<ffffffff8115ce6e>] do_last+0x5fe/0x880
 [<ffffffff8115dc0d>] path_openat+0xcd/0x3d0
 [<ffffffff8115e029>] do_filp_open+0x49/0xa0
 [<ffffffff8116a965>] ? alloc_fd+0x95/0x160
 [<ffffffff8114f0c7>] do_sys_open+0x107/0x1e0
 [<ffffffff810bcc3f>] ? audit_syscall_entry+0x1bf/0x1f0
 [<ffffffff8114f1e0>] sys_open+0x20/0x30
 [<ffffffff81484ec2>] system_call_fastpath+0x16/0x1b
[SNIP]
RIP  [<ffffffffa049444a>] __finish_chunk_alloc+0x20a/0x220 [btrfs]

The reason is:
Task1 Space balance task
do_chunk_alloc()
  __finish_chunk_alloc()
    update device info
    in the chunk tree
      alloc system metadata block
relocate system metadata block group
  set system metadata block group
  readonly, This block group is the
  only one that can allocate space. So
  there is no free space that can be
  allocated now.
        find no space and don't try
        to alloc new chunk, and then
        return ENOSPC
  BUG_ON() in __finish_chunk_alloc()
  was triggered.

Fix this bug by allocating a new system metadata chunk before relocating the
old one if we find there is no free space which can be allocated after setting
the old block group to be read-only.

Reported-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Tested-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
13 years agoBtrfs: tag pages for writeback in sync
Josef Bacik [Fri, 15 Jul 2011 21:26:38 +0000 (21:26 +0000)]
Btrfs: tag pages for writeback in sync

Everybody else does this, we need to do it too.  If we're syncing, we need to
tag the pages we're going to write for writeback so we don't end up writing the
same stuff over and over again if somebody is constantly redirtying our file.
This will keep us from having latencies with heavy sync workloads.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
13 years agoBtrfs: fix enospc problems with delalloc
Josef Bacik [Fri, 15 Jul 2011 15:16:44 +0000 (15:16 +0000)]
Btrfs: fix enospc problems with delalloc

So I had this brilliant idea to use atomic counters for outstanding and reserved
extents, but this turned out to be a bad idea.  Consider this where we have 1
outstanding extent and 1 reserved extent

Reserver Releaser
atomic_dec(outstanding) now 0
atomic_read(outstanding)+1 get 1
atomic_read(reserved) get 1
don't actually reserve anything because
they are the same
atomic_cmpxchg(reserved, 1, 0)
atomic_inc(outstanding)
atomic_add(0, reserved)
free reserved space for 1 extent

Then the reserver now has no actual space reserved for it, and when it goes to
finish the ordered IO it won't have enough space to do it's allocation and you
get those lovely warnings.

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
13 years agoBtrfs: don't flush delalloc arbitrarily
Josef Bacik [Fri, 15 Jul 2011 16:01:03 +0000 (16:01 +0000)]
Btrfs: don't flush delalloc arbitrarily

Kill the check to see if we have 512mb of reserved space in delalloc and
shrink_delalloc if we do.  This causes unexpected latencies and we have other
logic to see if we need to throttle.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
13 years agoBtrfs: use find_or_create_page instead of grab_cache_page
Josef Bacik [Mon, 11 Jul 2011 14:47:06 +0000 (10:47 -0400)]
Btrfs: use find_or_create_page instead of grab_cache_page

grab_cache_page will use mapping_gfp_mask(), which for all inodes is set to
GFP_HIGHUSER_MOVABLE.  So instead use find_or_create_page in all cases where we
need GFP_NOFS so we don't deadlock.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
13 years agoBtrfs: use a worker thread to do caching
Josef Bacik [Thu, 30 Jun 2011 18:42:28 +0000 (14:42 -0400)]
Btrfs: use a worker thread to do caching

A user reported a deadlock when copying a bunch of files.  This is because they
were low on memory and kthreadd got hung up trying to migrate pages for an
allocation when starting the caching kthread.  The page was locked by the person
starting the caching kthread.  To fix this we just need to use the async thread
stuff so that the threads are already created and we don't have to worry about
deadlocks.  Thanks,

Reported-by: Roman Mamedov <rm@romanrm.ru>
Signed-off-by: Josef Bacik <josef@redhat.com>
13 years agoMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/shaggy...
Linus Torvalds [Wed, 27 Jul 2011 16:26:39 +0000 (09:26 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/shaggy/jfs-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/shaggy/jfs-2.6:
  jfs: clean up some compiler warnings

13 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-fixes
Linus Torvalds [Wed, 27 Jul 2011 16:26:22 +0000 (09:26 -0700)]
Merge git://git./linux/kernel/git/steve/gfs2-2.6-fixes

* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-fixes:
  GFS2: Fix mount hang caused by certain access pattern to sysfs files

13 years agoMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
Linus Torvalds [Wed, 27 Jul 2011 16:25:15 +0000 (09:25 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/tiwai/sound-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6: (22 commits)
  ALSA: hda - Cirrus Logic CS421x support
  ALSA: Make pcm.h self-contained
  ALSA: hda - Allow codec-specific set_power_state ops
  ALSA: hda - Add post_suspend patch ops
  ALSA: hda - Make CONFIG_SND_HDA_POWER_SAVE depending on CONFIG_PM
  ALSA: hda - Make sure mute led reflects master mute state
  ALSA: hda - Fix invalid mute led state on resume of IDT codecs
  ASoC: Revert "ASoC: SAMSUNG: Add I2S0 internal dma driver"
  ALSA: hda - Add support of the 4 internal speakers on certain HP laptops
  ALSA: Make snd_pcm_debug_name usable outside pcm_lib
  ALSA: hda - Fix DAC filling for multi-connection pins in Realtek parser
  ASoC: dapm - Add methods to retrieve snd_card and soc_card from dapm context.
  ASoC: SAMSUNG: Add I2S0 internal dma driver
  ASoC: SAMSUNG: Modify I2S driver to support idma
  ASoC: davinci: add missing break statement
  ASoC: davinci: fix codec start and stop functions
  ASoC: dapm - add DAPM macro for external enum widgets
  ASoC: Acknowledge WM8962 interrupts before acting on them
  ASoC: sgtl5000: guide user when regulator support is needed
  ASoC: sgtl5000: refactor registering internal ldo
  ...

13 years agoMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Linus Torvalds [Wed, 27 Jul 2011 16:24:56 +0000 (09:24 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/dtor/input

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (53 commits)
  Input: synaptics - fix reporting of min coordinates
  Input: tegra-kbc - enable key autorepeat
  Input: kxtj9 - fix locking typo in kxtj9_set_poll()
  Input: kxtj9 - fix bug in probe()
  Input: intel-mid-touch - remove pointless checking for variable 'found'
  Input: hp_sdc - staticize hp_sdc_kicker()
  Input: pmic8xxx-keypad - fix a leak of the IRQ during init failure
  Input: cy8ctmg110_ts - set reset_pin and irq_pin from platform data
  Input: cy8ctmg110_ts - constify i2c_device_id table
  Input: cy8ctmg110_ts - fix checking return value of i2c_master_send
  Input: lifebook - make dmi callback functions return 1
  Input: atkbd - make dmi callback functions return 1
  Input: gpio_keys - switch to using SIMPLE_DEV_PM_OPS
  Input: gpio_keys - add support for device-tree platform data
  Input: aiptek - remove double define
  Input: synaptics - set minimum coordinates as reported by firmware
  Input: synaptics - process button bits in AGM packets
  Input: synaptics - rename set_slot to be more descriptive
  Input: synaptics - fuzz position for touchpad with reduced filtering
  Input: synaptics - set resolution for MT_POSITION_X/Y axes
  ...

13 years agoMerge branch 'next' of git://git.monstr.eu/linux-2.6-microblaze
Linus Torvalds [Wed, 27 Jul 2011 16:24:20 +0000 (09:24 -0700)]
Merge branch 'next' of git://git.monstr.eu/linux-2.6-microblaze

* 'next' of git://git.monstr.eu/linux-2.6-microblaze:
  microblaze: Do not show error message for 32 interrupt lines
  Revert "microblaze: PCI fix typo fault in of_node pointer moving into pci_bus"
  microblaze: PCI fix typo fault in of_node pointer moving into pci_bus
  microblaze: Add support for early console on mdm
  microblaze: Simplify early console binding from DT
  microblaze: Get early printk console earlier
  microblaze: Standardise cpuinfo output for cache policy
  microblaze: Unprivileged stream instruction awareness
  microblaze: trivial: Fix typo fault
  microblaze: exec: Remove redundant set_fs(USER_DS)
  microblaze: Remove duplicated prototype of start_thread()
  microblaze: Fix unaligned value saving to the stack for system with MMU
  microblaze/irqs: Do not trace arch_local_{*,irq_*} functions

13 years agostaging: brcm80211: Fix double include introduced by bad merge
Daniel Morsing [Wed, 27 Jul 2011 11:53:28 +0000 (13:53 +0200)]
staging: brcm80211: Fix double include introduced by bad merge

A merge with Linus' tree added a double include of linux/interrupt.h.
Fix by removing one of the includes.

Signed-off-by: Daniel Morsing <daniel.morsing@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agomicroblaze: Do not show error message for 32 interrupt lines
Michal Simek [Wed, 27 Jul 2011 08:45:32 +0000 (10:45 +0200)]
microblaze: Do not show error message for 32 interrupt lines

When interrupt controller uses 32 interrupts lines the kernel
show error message about mismatch in kind-of-intr parameter
because it exceeds u32. Recast fixs this issue.

Signed-off-by: Michal Simek <monstr@monstr.eu>
13 years agoMerge branch 'next' into for-linus
Dmitry Torokhov [Wed, 27 Jul 2011 07:54:47 +0000 (00:54 -0700)]
Merge branch 'next' into for-linus

13 years agoxfs: optimize the negative xattr caching
Christoph Hellwig [Tue, 26 Jul 2011 15:07:29 +0000 (15:07 +0000)]
xfs: optimize the negative xattr caching

Since the addition of file capabilities every write needs to read xattrs to
check if we have any capabilities to clear.  In Linux 3.0 Andi Kleen added
a flag to cache the fact that we do not have any attributes on an inode.
Make sure to already mark a file as not having any attributes when reading
it from disk in case it doesn't even have an attribute fork.  Based on an
earlier patch from Andi Kleen.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
13 years agoxfs: prevent against ioend livelocks in xfs_file_fsync
Christoph Hellwig [Tue, 26 Jul 2011 15:07:11 +0000 (15:07 +0000)]
xfs: prevent against ioend livelocks in xfs_file_fsync

We need to take some locks to prevent new ioends from coming in when we wait
for all existing ones to go away.  Up to Linux 3.0 that was done using the
i_mutex held by the VFS fsync code, but now that we are called without
it we need to take care of it ourselves.  Use the I/O lock instead of
i_mutex just like we do in other places.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
13 years agoxfs: flag all buffers as metadata
Christoph Hellwig [Tue, 26 Jul 2011 15:06:44 +0000 (15:06 +0000)]
xfs: flag all buffers as metadata

Now that REQ_META bios aren't treated specially in the CFQ I/O schedule
anymore, we can tag all buffers as metadata to make blktrace traces more
meaningful.  Note that we use buffers also to zero out partial blocks
in the preallocation / hole punching code, and while they operate on
data blocks the zeros written certainly aren't data.  I think this case
is borderline metadata enough to not bother special casing it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
13 years agoxfs: encapsulate a block of debug code
Alex Elder [Mon, 18 Jul 2011 18:14:09 +0000 (18:14 +0000)]
xfs: encapsulate a block of debug code

Pull into a helper function some debug-only code that validates a
xfs_da_blkinfo structure that's been read from disk.

Signed-off-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
13 years agoMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
Linus Torvalds [Wed, 27 Jul 2011 01:30:20 +0000 (18:30 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/viro/vfs-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  merge fchmod() and fchmodat() guts, kill ancient broken kludge
  xfs: fix misspelled S_IS...()
  xfs: get rid of open-coded S_ISREG(), etc.
  vfs: document locking requirements for d_move, __d_move and d_materialise_unique
  omfs: fix (mode & S_IFDIR) abuse
  btrfs: S_ISREG(mode) is not mode & S_IFREG...
  ima: fmode_t misspelled as mode_t...
  pci-label.c: size_t misspelled as mode_t
  jffs2: S_ISLNK(mode & S_IFMT) is pointless
  snd_msnd ->mode is fmode_t, not mode_t
  v9fs_iop_get_acl: get rid of unused variable
  vfs: dont chain pipe/anon/socket on superblock s_inodes list
  Documentation: Exporting: update description of d_splice_alias
  fs: add missing unlock in default_llseek()

13 years agoMerge branch 'next/devel2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux...
Linus Torvalds [Wed, 27 Jul 2011 00:42:18 +0000 (17:42 -0700)]
Merge branch 'next/devel2' of git://git./linux/kernel/git/arm/linux-arm-soc

* 'next/devel2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux-arm-soc: (47 commits)
  OMAP: Add debugfs node to show the summary of all clocks
  OMAP2+: hwmod: Follow the recommended PRCM module enable sequence
  OMAP2+: clock: allow per-SoC clock init code to prevent clockdomain calls from clock code
  OMAP2+: clockdomain: Add per clkdm lock to prevent concurrent state programming
  OMAP2+: PM: idle clkdms only if already in idle
  OMAP2+: clockdomain: add clkdm_in_hwsup()
  OMAP2+: clockdomain: Add 2 APIs to control clockdomain from hwmod framework
  OMAP: clockdomain: Remove redundant call to pwrdm_wait_transition()
  OMAP4: hwmod: Introduce the module control in hwmod control
  OMAP4: cm: Add two new APIs for modulemode control
  OMAP4: hwmod data: Add modulemode entry in omap_hwmod structure
  OMAP4: hwmod data: Add PRM context register offset
  OMAP4: prm: Remove deprecated functions
  OMAP4: prm: Replace warm reset API with the offset based version
  OMAP4: hwmod: Replace RSTCTRL absolute address with offset macros
  OMAP: hwmod: Wait the idle status to be disabled
  OMAP4: hwmod: Replace CLKCTRL absolute address with offset macros
  OMAP2+: hwmod: Init clkdm field at boot time
  OMAP4: hwmod data: Add clock domain attribute
  OMAP4: clock data: Add missing divider selection for auxclks
  ...

13 years agoMerge branch 'next/devel' of ssh://master.kernel.org/pub/scm/linux/kernel/git/arm...
Linus Torvalds [Wed, 27 Jul 2011 00:41:04 +0000 (17:41 -0700)]
Merge branch 'next/devel' of ssh:///linux/kernel/git/arm/linux-arm-soc

* 'next/devel' of ssh://master.kernel.org/pub/scm/linux/kernel/git/arm/linux-arm-soc: (128 commits)
  ARM: S5P64X0: External Interrupt Support
  ARM: EXYNOS4: Enable MFC on Samsung NURI
  ARM: EXYNOS4: Enable MFC on universal_c210
  ARM: S5PV210: Enable MFC on Goni
  ARM: S5P: Add support for MFC device
  ARM: EXYNOS4: Add support FIMD on SMDKC210
  ARM: EXYNOS4: Add platform device and helper functions for FIMD
  ARM: EXYNOS4: Add resource definition for FIMD
  ARM: EXYNOS4: Change devname for FIMD clkdev
  ARM: SAMSUNG: Add IRQ_I2S0 definition
  ARM: SAMSUNG: Add platform device for idma
  ARM: EXYNOS4: Add more registers to be saved and restored for PM
  ARM: EXYNOS4: Add more register addresses of CMU
  ARM: EXYNOS4: Add platform device for dwmci driver
  ARM: EXYNOS4: configure rtc-s3c on NURI
  ARM: EXYNOS4: configure MAX8903 secondary charger on NURI
  ARM: EXYNOS4: configure ADC on NURI
  ARM: EXYNOS4: configure MAX17042 fuel gauge on NURI
  ARM: EXYNOS4: configure regulators and PMIC(MAX8997) on NURI
  ARM: EXYNOS4: Increase NR_IRQS for devices with more IRQs
  ...

Fix up tons of silly conflicts:
 - arch/arm/mach-davinci/include/mach/psc.h
 - arch/arm/mach-exynos4/Kconfig
 - arch/arm/mach-exynos4/mach-smdkc210.c
 - arch/arm/mach-exynos4/pm.c
 - arch/arm/mach-imx/mm-imx1.c
 - arch/arm/mach-imx/mm-imx21.c
 - arch/arm/mach-imx/mm-imx25.c
 - arch/arm/mach-imx/mm-imx27.c
 - arch/arm/mach-imx/mm-imx31.c
 - arch/arm/mach-imx/mm-imx35.c
 - arch/arm/mach-mx5/mm.c
 - arch/arm/mach-s5pv210/mach-goni.c
 - arch/arm/mm/Kconfig

13 years agoMerge branch 'next/board' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux...
Linus Torvalds [Wed, 27 Jul 2011 00:13:04 +0000 (17:13 -0700)]
Merge branch 'next/board' of git://git./linux/kernel/git/arm/linux-arm-soc

* 'next/board' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux-arm-soc:
  ARM: S3C64XX: Configure backup battery charger on Cragganmore
  ARM: S3C64XX: Fix WM8915 IRQ polarity on Cragganmore
  ARM: S3C64XX: Configure supplies for all Cragganmore regulators
  ARM: S3C64XX: Refresh Cragganmore support
  ARM: S3C64XX: Initial support for Wolfson/Simtec Cragganmore/Banff
  OMAP4: Keyboard: Mux changes in the board file
  omap: blaze: add mmc5/wl1283 device support
  omap: 4430SDP: Register the card detect GPIO properly
  arm: omap3: cm-t35: add support for cm-t3730
  OMAP3: beagle: add support for beagleboard xM revision C
  OMAP3: rx-51: Add full regulator definitions
  omap: rx51: Platform support for lp5523 led chip

13 years agoMerge branch 'next/cross-platform' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Wed, 27 Jul 2011 00:12:10 +0000 (17:12 -0700)]
Merge branch 'next/cross-platform' of git://git./linux/kernel/git/arm/linux-arm-soc

* 'next/cross-platform' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux-arm-soc:
  ARM: Consolidate the clkdev header files
  ARM: set vga memory base at run-time
  ARM: convert PCI defines to variables
  ARM: pci: make pcibios_assign_all_busses use pci_has_flag
  ARM: remove unnecessary mach/hardware.h includes
  pci: move microblaze and powerpc pci flag functions into asm-generic
  powerpc: rename ppc_pci_*_flags to pci_*_flags

Fix up conflicts in arch/microblaze/include/asm/pci-bridge.h

13 years agoMerge branch 'next/fixes2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux...
Linus Torvalds [Wed, 27 Jul 2011 00:10:20 +0000 (17:10 -0700)]
Merge branch 'next/fixes2' of git://git./linux/kernel/git/arm/linux-arm-soc

* 'next/fixes2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux-arm-soc: (24 commits)
  ASoC: omap: McBSP: fix build breakage on OMAP1
  OMAP: hwmod: fix the i2c-reset timeout during bootup
  I2C: OMAP2+: add correct functionality flags to all omap2plus i2c dev_attr
  I2C: OMAP2+: Tag all OMAP2+ hwmod defintions with I2C IP revision
  I2C: OMAP1/OMAP2+: create omap I2C functionality flags for each cpu_... test
  I2C: OMAP2+:  Introduce I2C IP versioning constants
  I2C: OMAP2+: increase omap_i2c_dev_attr flags from u8 to u32
  I2C: OMAP2+: Set hwmod flags to only allow 16-bit accesses to i2c
  OMAP4: hwmod data: Change DSS main_clk scheme
  OMAP4: powerdomain data: Remove unsupported MPU powerdomain state
  OMAP4: clock data: Keep GPMC clocks always enabled and hardware managed
  OMAP4: powerdomain data: Fix core mem states and missing cefuse flag
  OMAP2+: PM: Initialise sleep_switch to a non-valid value
  OMAP4: hwmod data: Modify DSS opt clocks
  OMAP4: iommu: fix clock name
  omap: iovmm: s/sg_dma_len(sg)/sg->length/
  omap: iommu: fix pte programming
  arm: omap3: cm-t35: fix slow path warning
  arm: omap3: cm-t35: minor comments fixes
  omap: ZOOM: QUART: Request reset GPIO
  ...

13 years agoMerge branch 'next/soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux...
Linus Torvalds [Wed, 27 Jul 2011 00:09:31 +0000 (17:09 -0700)]
Merge branch 'next/soc' of git://git./linux/kernel/git/arm/linux-arm-soc

* 'next/soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux-arm-soc:
  MAINTAINERS: add maintainer of CSR SiRFprimaII machine
  ARM: CSR: initializing L2 cache
  ARM: CSR: mapping early DEBUG_LL uart
  ARM: CSR: Adding CSR SiRFprimaII board support
  OMAP4: clocks: Update the clock tree with 4460 clock nodes
  OMAP4: PRCM: OMAP4460 specific PRM and CM register bitshifts
  OMAP4: ID: add omap_has_feature for max freq supported
  OMAP: ID: introduce chip detection for OMAP4460
  ARM: Xilinx: merge board file into main platform code
  ARM: Xilinx: Adding Xilinx board support

Fix up conflicts in arch/arm/mach-omap2/cm-regbits-44xx.h

13 years agoMerge branch 'next-i2c' of git://git.fluff.org/bjdooks/linux
Linus Torvalds [Tue, 26 Jul 2011 23:55:45 +0000 (16:55 -0700)]
Merge branch 'next-i2c' of git://git.fluff.org/bjdooks/linux

* 'next-i2c' of git://git.fluff.org/bjdooks/linux:
  i2c-eg20t : Fix the issue of Combined R/W transfer mode
  i2c-eg20t : Support Combined R/W transfer mode
  i2c: Tegra: Add DeviceTree support

13 years agoasm-generic/atomic.h: allow SMP peeps to leverage this
Mike Frysinger [Tue, 26 Jul 2011 23:09:11 +0000 (16:09 -0700)]
asm-generic/atomic.h: allow SMP peeps to leverage this

Only a few core funcs need to be implemented for SMP systems, so allow the
arches to override them while getting the rest for free.

At least, this is enough to allow the Blackfin SMP port to use things.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: Arun Sharma <asharma@fb.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoasm-generic/atomic.h: add atomic_set_mask() helper
Mike Frysinger [Tue, 26 Jul 2011 23:09:10 +0000 (16:09 -0700)]
asm-generic/atomic.h: add atomic_set_mask() helper

Since arches are expected to implement this guy, add a common version for
people the same way as atomic_clear_mask is handled.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: Arun Sharma <asharma@fb.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoasm-generic/atomic.h: fix type used in atomic_clear_mask
Mike Frysinger [Tue, 26 Jul 2011 23:09:10 +0000 (16:09 -0700)]
asm-generic/atomic.h: fix type used in atomic_clear_mask

The atomic helpers are supposed to take an atomic_t pointer, not a random
unsigned long pointer.  So convert atomic_clear_mask over.

While we're here, also add some nice documentation to the func.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: Arun Sharma <asharma@fb.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoasm-generic/atomic.h: simplify inc/dec test helpers
Mike Frysinger [Tue, 26 Jul 2011 23:09:09 +0000 (16:09 -0700)]
asm-generic/atomic.h: simplify inc/dec test helpers

We already declared inc/dec helpers, so we don't need to call the
atomic_{add,sub}_return funcs directly.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: Arun Sharma <asharma@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoatomic: Update comments in atomic.h
Arun Sharma [Tue, 26 Jul 2011 23:09:08 +0000 (16:09 -0700)]
atomic: Update comments in atomic.h

This clarifies the differences between <linux/atomic.h> and
<asm-generic/atomic.h>

Signed-off-by: Arun Sharma <asharma@fb.com>
Suggested-by: Mike Frysinger <vapier.adi@gmail.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoatomic: cleanup asm-generic atomic*.h inclusion
Arun Sharma [Tue, 26 Jul 2011 23:09:08 +0000 (16:09 -0700)]
atomic: cleanup asm-generic atomic*.h inclusion

After changing all consumers of atomics to include <linux/atomic.h>, we
ran into some compile time errors due to this dependency chain:

linux/atomic.h
  -> asm/atomic.h
    -> asm-generic/atomic-long.h

where atomic-long.h could use funcs defined later in linux/atomic.h
without a prototype.  This patches moves the code that includes
asm-generic/atomic*.h to linux/atomic.h.

Archs that need <asm-generic/atomic64.h> need to select
CONFIG_GENERIC_ATOMIC64 from now on (some of them used to include it
unconditionally).

Compile tested on i386 and x86_64 with allnoconfig.

Signed-off-by: Arun Sharma <asharma@fb.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoatomic: move atomic_add_unless to generic code
Arun Sharma [Tue, 26 Jul 2011 23:09:07 +0000 (16:09 -0700)]
atomic: move atomic_add_unless to generic code

This is in preparation for more generic atomic primitives based on
__atomic_add_unless.

Signed-off-by: Arun Sharma <asharma@fb.com>
Signed-off-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoatomic: use <linux/atomic.h>
Arun Sharma [Tue, 26 Jul 2011 23:09:06 +0000 (16:09 -0700)]
atomic: use <linux/atomic.h>

This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>

Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoasm-generic: add another generic ext2 atomic bitops
Akinobu Mita [Tue, 26 Jul 2011 23:09:04 +0000 (16:09 -0700)]
asm-generic: add another generic ext2 atomic bitops

The majority of architectures implement ext2 atomic bitops as
test_and_{set,clear}_bit() without spinlock.

This adds this type of generic implementation in ext2-atomic-setbit.h and
use it wherever possible.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Suggested-by: Andreas Dilger <adilger@dilger.ca>
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agofail_make_request: cleanup should_fail_request
Akinobu Mita [Tue, 26 Jul 2011 23:09:03 +0000 (16:09 -0700)]
fail_make_request: cleanup should_fail_request

This changes should_fail_request() to more usable wrapper function of
should_fail().  It can avoid putting #ifdef CONFIG_FAIL_MAKE_REQUEST in
the middle of a function.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agofail_page_alloc: simplify debugfs initialization
Akinobu Mita [Tue, 26 Jul 2011 23:09:03 +0000 (16:09 -0700)]
fail_page_alloc: simplify debugfs initialization

Now cleanup_fault_attr_dentries() recursively removes a directory, So we
can simplify the error handling in the initialization code and no need
to hold dentry structs for each debugfs file.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agofailslab: simplify debugfs initialization
Akinobu Mita [Tue, 26 Jul 2011 23:09:02 +0000 (16:09 -0700)]
failslab: simplify debugfs initialization

Now cleanup_fault_attr_dentries() recursively removes a directory, So we
can simplify the error handling in the initialization code and no need
to hold dentry structs for each debugfs file.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agofault-injection: use debugfs_remove_recursive
Akinobu Mita [Tue, 26 Jul 2011 23:09:02 +0000 (16:09 -0700)]
fault-injection: use debugfs_remove_recursive

Use debugfs_remove_recursive() to simplify initialization and
deinitialization of fault injection debugfs files.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agofault-injection: cleanup simple attribute of stacktrace_depth
Akinobu Mita [Tue, 26 Jul 2011 23:09:01 +0000 (16:09 -0700)]
fault-injection: cleanup simple attribute of stacktrace_depth

Minor cosmetic changes for simple attribute of stacktrace_depth:

 - use min_t()
 - reduce #ifdef by moving a function
 - do not use partly capitalized function name

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agofault-injection: remove nonexistent function extern
Akinobu Mita [Tue, 26 Jul 2011 23:09:00 +0000 (16:09 -0700)]
fault-injection: remove nonexistent function extern

should_fail_srandom() does not exist.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agofault-injection: do not include unneeded header
Akinobu Mita [Tue, 26 Jul 2011 23:09:00 +0000 (16:09 -0700)]
fault-injection: do not include unneeded header

No need to include linux/kallsyms.h.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoramoops: make record_size a module parameter
Sergiu Iordache [Tue, 26 Jul 2011 23:08:59 +0000 (16:08 -0700)]
ramoops: make record_size a module parameter

The size of the dump is currently set using the RECORD_SIZE macro which
is set to a page size.  This patch makes the record size a module
parameter and allows it to be set through platform data as well to allow
larger dumps if needed.

Signed-off-by: Sergiu Iordache <sergiu@chromium.org>
Acked-by: Marco Stornelli <marco.stornelli@gmail.com>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoramoops: move dump_oops into platform data
Sergiu Iordache [Tue, 26 Jul 2011 23:08:58 +0000 (16:08 -0700)]
ramoops: move dump_oops into platform data

The platform driver currently allows setting the mem_size and
mem_address.

ince dump_oops is also a module parameter it would be more consistent if
it could be set through platform data as well.

Signed-off-by: Sergiu Iordache <sergiu@chromium.org>
Acked-by: Marco Stornelli <marco.stornelli@gmail.com>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoramoops: add new line to each print
Marco Stornelli [Tue, 26 Jul 2011 23:08:57 +0000 (16:08 -0700)]
ramoops: add new line to each print

Add new line to each print.

Signed-off-by: Marco Stornelli <marco.stornelli@gmail.com>
Reported-by: Stevie Trujillo <stevie.trujillo@gmail.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Américo Wang <xiyou.wangcong@gmail.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoramoops: use module parameters instead of platform data if not available
Marco Stornelli [Tue, 26 Jul 2011 23:08:57 +0000 (16:08 -0700)]
ramoops: use module parameters instead of platform data if not available

Use generic module parameters instead of platform data, if platform data
are not available.  This limitation has been introduced with commit
c3b92ce9e75 ("ramoops: use the platform data structure instead of module
params").

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Marco Stornelli <marco.stornelli@gmail.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Américo Wang <xiyou.wangcong@gmail.com>
Reported-by: Stevie Trujillo <stevie.trujillo@gmail.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoVmware balloon: switch to using sysem-wide freezable workqueue
Dmitry Torokhov [Tue, 26 Jul 2011 23:08:56 +0000 (16:08 -0700)]
Vmware balloon: switch to using sysem-wide freezable workqueue

With the arrival of concurrency-managed workqueues there is no need for
our driver to use dedicated workqueue; system-wide one should suffice just
fine.

[akpm@linux-foundation.org: fix comment layout & grammar]
Signed-off-by: Dmitry Torokhov <dtor@vmware.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agodrivers/w1/slaves/w1_therm.c: add support for DS28EA00
Christian Glindkamp [Tue, 26 Jul 2011 23:08:55 +0000 (16:08 -0700)]
drivers/w1/slaves/w1_therm.c: add support for DS28EA00

Signed-off-by: Christian Glindkamp <christian.glindkamp@taskit.de>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agopanic, vt: do not force oops output when panic_timeout < 0
Mandeep Singh Baines [Tue, 26 Jul 2011 23:08:54 +0000 (16:08 -0700)]
panic, vt: do not force oops output when panic_timeout < 0

Don't force output if you intend to reboot immediately.

In this patch, I'm disabling the functionality enabled by
vc->vc_panic_force_write if panic_timeout < 0 (i.e.  no timeout).
vc_panic_force_write is only enabled for fb video consoles if the
FBINFO_CAN_FORCE_OUTPUT flag is set.

For our application, we're using ram_oops to preserved the panic in
memory.  We want to reliably, and as fast as possible, machine_restart.
The vc_panic_force_write flag results in a bunch of graphics driver code
to be invoked which slows down restart and decreases reliability.  Since
we're already storing the panic in RAM and are going to reboot
immediately, there is no benefit in mode switching back to the vc in
order to display the panic output.  The log buffer will get flushed by
the console_unblank() call so remote management consoles should see all
output.

Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Olaf Hering <olaf@aepfle.de>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Dave Airlie <airlied@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agopanic: panic=-1 for immediate reboot
Hugh Dickins [Tue, 26 Jul 2011 23:08:52 +0000 (16:08 -0700)]
panic: panic=-1 for immediate reboot

When a kernel BUG or oops occurs, ChromeOS intends to panic and
immediately reboot, with stacktrace and other messages preserved in RAM
across reboot.

But the longer we delay, the more likely the user is to poweroff and
lose the info.

panic_timeout (seconds before rebooting) is set by panic= boot option or
sysctl or /proc/sys/kernel/panic; but 0 means wait forever, so at
present we have to delay at least 1 second.

Let a negative number mean reboot immediately (with the small cosmetic
benefit of suppressing that newline-less "Rebooting in %d seconds.."
message).

Signed-off-by: Hugh Dickins <hughd@chromium.org>
Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Olaf Hering <olaf@aepfle.de>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Dave Airlie <airlied@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoDocumentation/DMA-API-HOWTO.txt: fix misleading example
Michal Miroslaw [Tue, 26 Jul 2011 23:08:51 +0000 (16:08 -0700)]
Documentation/DMA-API-HOWTO.txt: fix misleading example

See: DMA-API.txt, part Id, DMA_FROM_DEVICE description.

Signed-off-by: Michal Miroslaw <mirq-linux@rere.qmqm.pl>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoinclude/linux/dma-mapping.h: remove DMA_xxBIT_MASK macros
WANG Cong [Tue, 26 Jul 2011 23:08:50 +0000 (16:08 -0700)]
include/linux/dma-mapping.h: remove DMA_xxBIT_MASK macros

git grep shows there are no users in tree, so we can remove them safely.

Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agogcov: disable CONSTRUCTORS for UML
Vitaliy Ivanov [Tue, 26 Jul 2011 23:08:49 +0000 (16:08 -0700)]
gcov: disable CONSTRUCTORS for UML

Selecting GCOV for UML causing configuration mismatch:

  warning: (GCOV_KERNEL) selects CONSTRUCTORS which has unmet direct dependencies (!UML)

Constructors are not needed for UML.

Signed-off-by: Vitaliy Ivanov <vitalivanov@gmail.com>
Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Acked-by: Richard Weinberger <richard@nod.at>
Acked-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agodrivers/edac/mpc85xx_edac.c: correct offset_in_page mask bits in edac_mc_handle_ce()
Kai.Jiang [Tue, 26 Jul 2011 23:08:49 +0000 (16:08 -0700)]
drivers/edac/mpc85xx_edac.c: correct offset_in_page mask bits in edac_mc_handle_ce()

Parameter offset_in_page in edac_mc_handle_ce() should mask the higher
bits above the page size, not the lower bits.  The original input
sometimes causes a crash.

Signed-off-by: Kai.Jiang <Kai.Jiang@freescale.com>
Signed-off-by: Shaohui Xie <Shaohui.Xie@freescale.com>
Cc: Anton Vorontsov <avorontsov@mvista.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoipc: introduce shm_rmid_forced sysctl
Vasiliy Kulikov [Tue, 26 Jul 2011 23:08:48 +0000 (16:08 -0700)]
ipc: introduce shm_rmid_forced sysctl

Add support for the shm_rmid_forced sysctl.  If set to 1, all shared
memory objects in current ipc namespace will be automatically forced to
use IPC_RMID.

The POSIX way of handling shmem allows one to create shm objects and
call shmdt(), leaving shm object associated with no process, thus
consuming memory not counted via rlimits.

With shm_rmid_forced=1 the shared memory object is counted at least for
one process, so OOM killer may effectively kill the fat process holding
the shared memory.

It obviously breaks POSIX - some programs relying on the feature would
stop working.  So set shm_rmid_forced=1 only if you're sure nobody uses
"orphaned" memory.  Use shm_rmid_forced=0 by default for compatability
reasons.

The feature was previously impemented in -ow as a configure option.

[akpm@linux-foundation.org: fix documentation, per Randy]
[akpm@linux-foundation.org: fix warning]
[akpm@linux-foundation.org: readability/conventionality tweaks]
[akpm@linux-foundation.org: fix shm_rmid_forced/shm_forced_rmid confusion, use standard comment layout]
Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: "Serge E. Hallyn" <serge.hallyn@canonical.com>
Cc: Daniel Lezcano <daniel.lezcano@free.fr>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Solar Designer <solar@openwall.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoipc/mqueue.c: fix mq_open() return value
Jiri Slaby [Tue, 26 Jul 2011 23:08:47 +0000 (16:08 -0700)]
ipc/mqueue.c: fix mq_open() return value

We return ENOMEM from mqueue_get_inode even when we have enough memory.
Namely in case the system rlimit of mqueue was reached.  This error
propagates to mq_queue and user sees the error unexpectedly.  So fix
this up to properly return EMFILE as described in the manpage:

EMFILE The process already has the maximum number of files and
       message queues open.

instead of:

ENOMEM Insufficient memory.

With the previous patch we just switch to ERR_PTR/PTR_ERR/IS_ERR error
handling here.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoipc/mqueue.c: refactor failure handling
Jiri Slaby [Tue, 26 Jul 2011 23:08:46 +0000 (16:08 -0700)]
ipc/mqueue.c: refactor failure handling

If new_inode fails to allocate an inode we need only to return with
NULL.  But now we test the opposite and have all the work in a nested
block.  So do the opposite to save one indentation level (and remove
unnecessary line breaks).

This is only a preparation/cleanup for the next patch where we fix up
return values from mqueue_get_inode.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agocpumask: add cpumask_var_t documentation
KOSAKI Motohiro [Tue, 26 Jul 2011 23:08:45 +0000 (16:08 -0700)]
cpumask: add cpumask_var_t documentation

cpumask_var_t has one notable difference from cpumask_t.  Add the
explanation.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Thiago Farina <tfransosi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agocpumask: alloc_cpumask_var() use NUMA_NO_NODE
KOSAKI Motohiro [Tue, 26 Jul 2011 23:08:44 +0000 (16:08 -0700)]
cpumask: alloc_cpumask_var() use NUMA_NO_NODE

NUMA_NO_NODE and numa_node_id() have different meanings.  NUMA_NO_NODE is
obviously the recommended fallback.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agocpumask: convert for_each_cpumask() with for_each_cpu()
KOSAKI Motohiro [Tue, 26 Jul 2011 23:08:44 +0000 (16:08 -0700)]
cpumask: convert for_each_cpumask() with for_each_cpu()

Adapt new API fashion.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agofs/exec.c:acct_arg_size(): ptl is no longer needed for add_mm_counter()
Oleg Nesterov [Tue, 26 Jul 2011 23:08:43 +0000 (16:08 -0700)]
fs/exec.c:acct_arg_size(): ptl is no longer needed for add_mm_counter()

acct_arg_size() takes ->page_table_lock around add_mm_counter() if
!SPLIT_RSS_COUNTING.  This is not needed after commit 172703b08cd0 ("mm:
delete non-atomic mm counter implementation").

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Matt Fleming <matt.fleming@linux.intel.com>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoexec: do not retry load_binary method if CONFIG_MODULES=n
Tetsuo Handa [Tue, 26 Jul 2011 23:08:42 +0000 (16:08 -0700)]
exec: do not retry load_binary method if CONFIG_MODULES=n

If CONFIG_MODULES=n, it makes no sense to retry the list of binary formats
handler because the list will not be modified by request_module().

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Richard Weinberger <richard@nod.at>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoexec: do not call request_module() twice from search_binary_handler()
Tetsuo Handa [Tue, 26 Jul 2011 23:08:41 +0000 (16:08 -0700)]
exec: do not call request_module() twice from search_binary_handler()

Currently, search_binary_handler() tries to load binary loader module
using request_module() if a loader for the requested program is not yet
loaded.  But second attempt of request_module() does not affect the result
of search_binary_handler().

If request_module() triggered recursion, calling request_module() twice
causes 2 to the power of MAX_KMOD_CONCURRENT (= 50) repetitions.  It is
not an infinite loop but is sufficient for users to consider as a hang up.

Therefore, this patch changes not to call request_module() twice, making 1
to the power of MAX_KMOD_CONCURRENT repetitions in case of recursion.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: Richard Weinberger <richard@nod.at>
Tested-by: Richard Weinberger <richard@nod.at>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agofs/exec.c: use BUILD_BUG_ON for VM_STACK_FLAGS & VM_STACK_INCOMPLETE_SETUP
Michal Hocko [Tue, 26 Jul 2011 23:08:40 +0000 (16:08 -0700)]
fs/exec.c: use BUILD_BUG_ON for VM_STACK_FLAGS & VM_STACK_INCOMPLETE_SETUP

Commit a8bef8ff6ea1 ("mm: migration: avoid race between
shift_arg_pages() and rmap_walk() during migration by not migrating
temporary stacks") introduced a BUG_ON() to ensure that VM_STACK_FLAGS
and VM_STACK_INCOMPLETE_SETUP do not overlap.  The check is a compile
time one, so BUILD_BUG_ON is more appropriate.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Richard Weinberger <richard@nod.at>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agokernel/fork.c: fix a few coding style issues
Daniel Rebelo de Oliveira [Tue, 26 Jul 2011 23:08:39 +0000 (16:08 -0700)]
kernel/fork.c: fix a few coding style issues

Signed-off-by: Daniel Rebelo de Oliveira <psykon@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoproc: fix a race in do_io_accounting()
Vasiliy Kulikov [Tue, 26 Jul 2011 23:08:38 +0000 (16:08 -0700)]
proc: fix a race in do_io_accounting()

If an inode's mode permits opening /proc/PID/io and the resulting file
descriptor is kept across execve() of a setuid or similar binary, the
ptrace_may_access() check tries to prevent using this fd against the
task with escalated privileges.

Unfortunately, there is a race in the check against execve().  If
execve() is processed after the ptrace check, but before the actual io
information gathering, io statistics will be gathered from the
privileged process.  At least in theory this might lead to gathering
sensible information (like ssh/ftp password length) that wouldn't be
available otherwise.

Holding task->signal->cred_guard_mutex while gathering the io
information should protect against the race.

The order of locking is similar to the one inside of ptrace_attach():
first goes cred_guard_mutex, then lock_task_sighand().

Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoprocfs: return ENOENT on opening a being-removed proc entry
Daisuke Ogino [Tue, 26 Jul 2011 23:08:37 +0000 (16:08 -0700)]
procfs: return ENOENT on opening a being-removed proc entry

Change the return value to ENOENT.  This return value is then returned
when opening the proc entry that have been removed.  For example,
open("/proc/bus/pci/XX/YY") when the corresponding device is being
hot-removed.

Signed-off-by: Daisuke Ogino <ogino.daisuke@jp.fujitsu.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoh8300/m68k/xtensa: __FD_ISSET should return 0/1
Andrew Morton [Tue, 26 Jul 2011 23:08:35 +0000 (16:08 -0700)]
h8300/m68k/xtensa: __FD_ISSET should return 0/1

Harmonise these return values with other architectures.  In some cases
this affects all compilers and in other cases non-gcc compilers only.

Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Ulrich Drepper <drepper@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agodo_coredump: fix the "ispipe" error check
Oleg Nesterov [Tue, 26 Jul 2011 23:08:34 +0000 (16:08 -0700)]
do_coredump: fix the "ispipe" error check

do_coredump() assumes that if format_corename() fails it should return
-ENOMEM.  This is not true, for example cn_print_exe_file() can propagate
the error from d_path.  Even if it was true, this is too fragile.  Change
the code to check "ispipe < 0".

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reviewed-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agocoredump: escape / in hostname and comm
Jiri Slaby [Tue, 26 Jul 2011 23:08:33 +0000 (16:08 -0700)]
coredump: escape / in hostname and comm

Change every occurence of / in comm and hostname to !.  If the process
changes its name to contain /, the core is not dumped (if the directory
tree doesn't exist like that).  The same with hostname being something
like myhost/3.  Fix this behaviour by using the escape loop used in %E.
(We extract it to a separate function.)

Now both with comm == myprocess/1 and hostname == myhost/1, the core is
dumped like (kernel.core_pattern='core.%p.%e.%h):
core.2349.myprocess!1.myhost!1

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agocoredump: use task comm instead of (unknown)
Jiri Slaby [Tue, 26 Jul 2011 23:08:32 +0000 (16:08 -0700)]
coredump: use task comm instead of (unknown)

If we don't know the file corresponding to the binary (i.e.  exe_file is
unknown), use "task->comm (path unknown)" instead of simple "(unknown)"
as suggested by ak.

The fallback is the same as %e except it will append "(path unknown)".

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agoptrace: unify show_regs() prototype
Mike Frysinger [Tue, 26 Jul 2011 23:08:31 +0000 (16:08 -0700)]
ptrace: unify show_regs() prototype

[ poleg@redhat.com: no need to declare show_regs() in ptrace.h, sched.h does this ]
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agocpusets: randomize node rotor used in cpuset_mem_spread_node()
Michal Hocko [Tue, 26 Jul 2011 23:08:30 +0000 (16:08 -0700)]
cpusets: randomize node rotor used in cpuset_mem_spread_node()

[ This patch has already been accepted as commit 0ac0c0d0f837 but later
  reverted (commit 35926ff5fba8) because it itroduced arch specific
  __node_random which was defined only for x86 code so it broke other
  archs.  This is a followup without any arch specific code.  Other than
  that there are no functional changes.]

Some workloads that create a large number of small files tend to assign
too many pages to node 0 (multi-node systems).  Part of the reason is
that the rotor (in cpuset_mem_spread_node()) used to assign nodes starts
at node 0 for newly created tasks.

This patch changes the rotor to be initialized to a random node number
of the cpuset.

[akpm@linux-foundation.org: fix layout]
[Lee.Schermerhorn@hp.com: Define stub numa_random() for !NUMA configuration]
[mhocko@suse.cz: Make it arch independent]
[akpm@linux-foundation.org: fix CONFIG_NUMA=y, MAX_NUMNODES>1 build]
Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Paul Menage <menage@google.com>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Robin Holt <holt@sgi.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Jack Steiner <steiner@sgi.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Paul Menage <menage@google.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Robin Holt <holt@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agomemcg: get rid of percpu_charge_mutex lock
Michal Hocko [Tue, 26 Jul 2011 23:08:29 +0000 (16:08 -0700)]
memcg: get rid of percpu_charge_mutex lock

percpu_charge_mutex protects from multiple simultaneous per-cpu charge
caches draining because we might end up having too many work items.  At
least this was the case until commit 26fe61684449 ("memcg: fix percpu
cached charge draining frequency") when we introduced a more targeted
draining for async mode.

Now that also sync draining is targeted we can safely remove mutex
because we will not send more work than the current number of CPUs.
FLUSHING_CACHED_CHARGE protects from sending the same work multiple
times and stock->nr_pages == 0 protects from pointless sending a work if
there is obviously nothing to be done.  This is of course racy but we
can live with it as the race window is really small (we would have to
see FLUSHING_CACHED_CHARGE cleared while nr_pages would be still
non-zero).

The only remaining place where we can race is synchronous mode when we
rely on FLUSHING_CACHED_CHARGE test which might have been set by other
drainer on the same group but we should wait in that case as well.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agomemcg: add mem_cgroup_same_or_subtree() helper
Michal Hocko [Tue, 26 Jul 2011 23:08:29 +0000 (16:08 -0700)]
memcg: add mem_cgroup_same_or_subtree() helper

We are checking whether a given two groups are same or at least in the
same subtree of a hierarchy at several places.  Let's make a helper for
it to make code easier to read.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agomemcg: unify sync and async per-cpu charge cache draining
Michal Hocko [Tue, 26 Jul 2011 23:08:28 +0000 (16:08 -0700)]
memcg: unify sync and async per-cpu charge cache draining

Currently we have two ways how to drain per-CPU caches for charges.
drain_all_stock_sync will synchronously drain all caches while
drain_all_stock_async will asynchronously drain only those that refer to
a given memory cgroup or its subtree in hierarchy.  Targeted async
draining has been introduced by 26fe6168 (memcg: fix percpu cached
charge draining frequency) to reduce the cpu workers number.

sync draining is currently triggered only from mem_cgroup_force_empty
which is triggered only by userspace (mem_cgroup_force_empty_write) or
when a cgroup is removed (mem_cgroup_pre_destroy).  Although these are
not usually frequent operations it still makes some sense to do targeted
draining as well, especially if the box has many CPUs.

This patch unifies both methods to use the single code (drain_all_stock)
which relies on the original async implementation and just adds
flush_work to wait on all caches that are still under work for the sync
mode.  We are using FLUSHING_CACHED_CHARGE bit check to prevent from
waiting on a work that we haven't triggered.  Please note that both sync
and async functions are currently protected by percpu_charge_mutex so we
cannot race with other drainers.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agomemcg: do not try to drain per-cpu caches without pages
Michal Hocko [Tue, 26 Jul 2011 23:08:27 +0000 (16:08 -0700)]
memcg: do not try to drain per-cpu caches without pages

drain_all_stock_async tries to optimize a work to be done on the work
queue by excluding any work for the current CPU because it assumes that
the context we are called from already tried to charge from that cache
and it's failed so it must be empty already.

While the assumption is correct we can optimize it even more by checking
the current number of pages in the cache.  This will also reduce a work
on other CPUs with an empty stock.

For the current CPU we can simply call drain_local_stock rather than
deferring it to the work queue.

[kamezawa.hiroyu@jp.fujitsu.com: use drain_local_stock for current CPU optimization]
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agomemcg: add memory.vmscan_stat
KAMEZAWA Hiroyuki [Tue, 26 Jul 2011 23:08:26 +0000 (16:08 -0700)]
memcg: add memory.vmscan_stat

The commit log of 0ae5e89c60c9 ("memcg: count the soft_limit reclaim
in...") says it adds scanning stats to memory.stat file.  But it doesn't
because we considered we needed to make a concensus for such new APIs.

This patch is a trial to add memory.scan_stat. This shows
  - the number of scanned pages(total, anon, file)
  - the number of rotated pages(total, anon, file)
  - the number of freed pages(total, anon, file)
  - the number of elaplsed time (including sleep/pause time)

  for both of direct/soft reclaim.

The biggest difference with oringinal Ying's one is that this file
can be reset by some write, as

  # echo 0 ...../memory.scan_stat

Example of output is here. This is a result after make -j 6 kernel
under 300M limit.

  [kamezawa@bluextal ~]$ cat /cgroup/memory/A/memory.scan_stat
  [kamezawa@bluextal ~]$ cat /cgroup/memory/A/memory.vmscan_stat
  scanned_pages_by_limit 9471864
  scanned_anon_pages_by_limit 6640629
  scanned_file_pages_by_limit 2831235
  rotated_pages_by_limit 4243974
  rotated_anon_pages_by_limit 3971968
  rotated_file_pages_by_limit 272006
  freed_pages_by_limit 2318492
  freed_anon_pages_by_limit 962052
  freed_file_pages_by_limit 1356440
  elapsed_ns_by_limit 351386416101
  scanned_pages_by_system 0
  scanned_anon_pages_by_system 0
  scanned_file_pages_by_system 0
  rotated_pages_by_system 0
  rotated_anon_pages_by_system 0
  rotated_file_pages_by_system 0
  freed_pages_by_system 0
  freed_anon_pages_by_system 0
  freed_file_pages_by_system 0
  elapsed_ns_by_system 0
  scanned_pages_by_limit_under_hierarchy 9471864
  scanned_anon_pages_by_limit_under_hierarchy 6640629
  scanned_file_pages_by_limit_under_hierarchy 2831235
  rotated_pages_by_limit_under_hierarchy 4243974
  rotated_anon_pages_by_limit_under_hierarchy 3971968
  rotated_file_pages_by_limit_under_hierarchy 272006
  freed_pages_by_limit_under_hierarchy 2318492
  freed_anon_pages_by_limit_under_hierarchy 962052
  freed_file_pages_by_limit_under_hierarchy 1356440
  elapsed_ns_by_limit_under_hierarchy 351386416101
  scanned_pages_by_system_under_hierarchy 0
  scanned_anon_pages_by_system_under_hierarchy 0
  scanned_file_pages_by_system_under_hierarchy 0
  rotated_pages_by_system_under_hierarchy 0
  rotated_anon_pages_by_system_under_hierarchy 0
  rotated_file_pages_by_system_under_hierarchy 0
  freed_pages_by_system_under_hierarchy 0
  freed_anon_pages_by_system_under_hierarchy 0
  freed_file_pages_by_system_under_hierarchy 0
  elapsed_ns_by_system_under_hierarchy 0

total_xxxx is for hierarchy management.

This will be useful for further memcg developments and need to be
developped before we do some complicated rework on LRU/softlimit
management.

This patch adds a new struct memcg_scanrecord into scan_control struct.
sc->nr_scanned at el is not designed for exporting information.  For
example, nr_scanned is reset frequentrly and incremented +2 at scanning
mapped pages.

To avoid complexity, I added a new param in scan_control which is for
exporting scanning score.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Ying Han <yinghan@google.com>
Cc: Andrew Bresticker <abrestic@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agomemcg: fix behavior of mem_cgroup_resize_limit()
Daisuke Nishimura [Tue, 26 Jul 2011 23:08:25 +0000 (16:08 -0700)]
memcg: fix behavior of mem_cgroup_resize_limit()

Commit 22a668d7c3ef ("memcg: fix behavior under memory.limit equals to
memsw.limit") introduced "memsw_is_minimum" flag, which becomes true
when mem_limit == memsw_limit.  The flag is checked at the beginning of
reclaim, and "noswap" is set if the flag is true, because using swap is
meaningless in this case.

This works well in most cases, but when we try to shrink mem_limit,
which is the same as memsw_limit now, we might fail to shrink mem_limit
because swap doesn't used.

This patch fixes this behavior by:
 - check MEM_CGROUP_RECLAIM_SHRINK at the begining of reclaim
 - If it is set, don't set "noswap" flag even if memsw_is_minimum is true.

Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <bsingharora@gmail.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Ying Han <yinghan@google.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agomemcg: fix vmscan count in small memcgs
KAMEZAWA Hiroyuki [Tue, 26 Jul 2011 23:08:24 +0000 (16:08 -0700)]
memcg: fix vmscan count in small memcgs

Commit 246e87a93934 ("memcg: fix get_scan_count() for small targets")
fixes the memcg/kswapd behavior against small targets and prevent vmscan
priority too high.

But the implementation is too naive and adds another problem to small
memcg.  It always force scan to 32 pages of file/anon and doesn't handle
swappiness and other rotate_info.  It makes vmscan to scan anon LRU
regardless of swappiness and make reclaim bad.  This patch fixes it by
adjusting scanning count with regard to swappiness at el.

At a test "cat 1G file under 300M limit." (swappiness=20)
 before patch
        scanned_pages_by_limit 360919
        scanned_anon_pages_by_limit 180469
        scanned_file_pages_by_limit 180450
        rotated_pages_by_limit 31
        rotated_anon_pages_by_limit 25
        rotated_file_pages_by_limit 6
        freed_pages_by_limit 180458
        freed_anon_pages_by_limit 19
        freed_file_pages_by_limit 180439
        elapsed_ns_by_limit 429758872
 after patch
        scanned_pages_by_limit 180674
        scanned_anon_pages_by_limit 24
        scanned_file_pages_by_limit 180650
        rotated_pages_by_limit 35
        rotated_anon_pages_by_limit 24
        rotated_file_pages_by_limit 11
        freed_pages_by_limit 180634
        freed_anon_pages_by_limit 0
        freed_file_pages_by_limit 180634
        elapsed_ns_by_limit 367119089
        scanned_pages_by_system 0

the numbers of scanning anon are decreased(as expected), and elapsed time
reduced. By this patch, small memcgs will work better.
(*) Because the amount of file-cache is much bigger than anon,
    recalaim_stat's rotate-scan counter make scanning files more.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Ying Han <yinghan@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agomemcg: change memcg_oom_mutex to spinlock
Michal Hocko [Tue, 26 Jul 2011 23:08:24 +0000 (16:08 -0700)]
memcg: change memcg_oom_mutex to spinlock

memcg_oom_mutex is used to protect memcg OOM path and eventfd interface
for oom_control.  None of the critical sections which it protects sleep
(eventfd_signal works from atomic context and the rest are simple linked
list resp.  oom_lock atomic operations).

Mutex is also too heavyweight for those code paths because it triggers a
lot of scheduling.  It also makes makes convoying effects more visible
when we have a big number of oom killing because we take the lock
mutliple times during mem_cgroup_handle_oom so we have multiple places
where many processes can sleep.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agomemcg: make oom_lock 0 and 1 based rather than counter
Michal Hocko [Tue, 26 Jul 2011 23:08:23 +0000 (16:08 -0700)]
memcg: make oom_lock 0 and 1 based rather than counter

Commit 867578cb ("memcg: fix oom kill behavior") introduced a oom_lock
counter which is incremented by mem_cgroup_oom_lock when we are about to
handle memcg OOM situation.  mem_cgroup_handle_oom falls back to a sleep
if oom_lock > 1 to prevent from multiple oom kills at the same time.
The counter is then decremented by mem_cgroup_oom_unlock called from the
same function.

This works correctly but it can lead to serious starvations when we have
many processes triggering OOM and many CPUs available for them (I have
tested with 16 CPUs).

Consider a process (call it A) which gets the oom_lock (the first one
that got to mem_cgroup_handle_oom and grabbed memcg_oom_mutex) and other
processes that are blocked on the mutex.  While A releases the mutex and
calls mem_cgroup_out_of_memory others will wake up (one after another)
and increase the counter and fall into sleep (memcg_oom_waitq).

Once A finishes mem_cgroup_out_of_memory it takes the mutex again and
decreases oom_lock and wakes other tasks (if releasing memory by
somebody else - e.g.  killed process - hasn't done it yet).

A testcase would look like:
  Assume malloc XXX is a program allocating XXX Megabytes of memory
  which touches all allocated pages in a tight loop
  # swapoff SWAP_DEVICE
  # cgcreate -g memory:A
  # cgset -r memory.oom_control=0   A
  # cgset -r memory.limit_in_bytes= 200M
  # for i in `seq 100`
  # do
  #     cgexec -g memory:A   malloc 10 &
  # done

The main problem here is that all processes still race for the mutex and
there is no guarantee that we will get counter back to 0 for those that
got back to mem_cgroup_handle_oom.  In the end the whole convoy
in/decreases the counter but we do not get to 1 that would enable
killing so nothing useful can be done.  The time is basically unbounded
because it highly depends on scheduling and ordering on mutex (I have
seen this taking hours...).

This patch replaces the counter by a simple {un}lock semantic.  As
mem_cgroup_oom_{un}lock works on the a subtree of a hierarchy we have to
make sure that nobody else races with us which is guaranteed by the
memcg_oom_mutex.

We have to be careful while locking subtrees because we can encounter a
subtree which is already locked: hierarchy:

          A
        /   \
       B     \
      /\      \
     C  D     E

B - C - D tree might be already locked.  While we want to enable locking
E subtree because OOM situations cannot influence each other we
definitely do not want to allow locking A.

Therefore we have to refuse lock if any subtree is already locked and
clear up the lock for all nodes that have been set up to the failure
point.

On the other hand we have to make sure that the rest of the world will
recognize that a group is under OOM even though it doesn't have a lock.
Therefore we have to introduce under_oom variable which is incremented
and decremented for the whole subtree when we enter resp.  leave
mem_cgroup_handle_oom.  under_oom, unlike oom_lock, doesn't need be
updated under memcg_oom_mutex because its users only check a single
group and they use atomic operations for that.

This can be checked easily by the following test case:

  # cgcreate -g memory:A
  # cgset -r memory.use_hierarchy=1 A
  # cgset -r memory.oom_control=1   A
  # cgset -r memory.limit_in_bytes= 100M
  # cgset -r memory.memsw.limit_in_bytes= 100M
  # cgcreate -g memory:A/B
  # cgset -r memory.oom_control=1 A/B
  # cgset -r memory.limit_in_bytes=20M
  # cgset -r memory.memsw.limit_in_bytes=20M
  # cgexec -g memory:A/B malloc 30  &    #->this will be blocked by OOM of group B
  # cgexec -g memory:A   malloc 80  &    #->this will be blocked by OOM of group A

While B gets oom_lock A will not get it.  Both of them go into sleep and
wait for an external action.  We can make the limit higher for A to
enforce waking it up

  # cgset -r memory.memsw.limit_in_bytes=300M A
  # cgset -r memory.limit_in_bytes=300M A

malloc in A has to wake up even though it doesn't have oom_lock.

Finally, the unlock path is very easy because we always unlock only the
subtree we have locked previously while we always decrement under_oom.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 years agomemcg: consolidate memory cgroup lru stat functions
KAMEZAWA Hiroyuki [Tue, 26 Jul 2011 23:08:22 +0000 (16:08 -0700)]
memcg: consolidate memory cgroup lru stat functions

In mm/memcontrol.c, there are many lru stat functions as..

  mem_cgroup_zone_nr_lru_pages
  mem_cgroup_node_nr_file_lru_pages
  mem_cgroup_nr_file_lru_pages
  mem_cgroup_node_nr_anon_lru_pages
  mem_cgroup_nr_anon_lru_pages
  mem_cgroup_node_nr_unevictable_lru_pages
  mem_cgroup_nr_unevictable_lru_pages
  mem_cgroup_node_nr_lru_pages
  mem_cgroup_nr_lru_pages
  mem_cgroup_get_local_zonestat

Some of them are under #ifdef MAX_NUMNODES >1 and others are not.
This seems bad. This patch consolidates all functions into

  mem_cgroup_zone_nr_lru_pages()
  mem_cgroup_node_nr_lru_pages()
  mem_cgroup_nr_lru_pages()

For these functions, "which LRU?" information is passed by a mask.

example:
  mem_cgroup_nr_lru_pages(mem, BIT(LRU_ACTIVE_ANON))

And I added some macro as ALL_LRU, ALL_LRU_FILE, ALL_LRU_ANON.

example:
  mem_cgroup_nr_lru_pages(mem, ALL_LRU)

BTW, considering layout of NUMA memory placement of counters, this patch seems
to be better.

Now, when we gather all LRU information, we scan in following orer
    for_each_lru -> for_each_node -> for_each_zone.

This means we'll touch cache lines in different node in turn.

After patch, we'll scan
    for_each_node -> for_each_zone -> for_each_lru(mask)

Then, we'll gather information in the same cacheline at once.

[akpm@linux-foundation.org: fix warnigns, build error]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Ying Han <yinghan@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>