Cyrill Gorcunov [Sat, 3 Nov 2012 00:43:02 +0000 (11:43 +1100)]
procfs: add VmFlags field in smaps output
During c/r sessions we've found that there is no way at the moment to
fetch some VMA associated flags, such as mlock() and madvise().
This leads us to a problem -- we don't know if we should call for mlock()
and/or madvise() after restore on the vma area we're bringing back to
life.
This patch intorduces a new field into "smaps" output called VmFlags,
where all set flags associated with the particular VMA is shown as two
letter mnemonics.
[ Strictly speaking for c/r we only need mlock/madvise bits but it has been
said that providing just a few flags looks somehow inconsistent. So all
flags are here now. ]
This feature is made available on CONFIG_CHECKPOINT_RESTORE=n kernels, as
other applications may start to use these fields.
The data is encoded in a somewhat awkward two letters mnemonic form, to
encourage userspace to be prepared for fields being added or removed in
the future.
[a.p.zijlstra@chello.nl: props to use for_each_set_bit]
[sfr@canb.auug.org.au: props to use array instead of struct]
[akpm@linux-foundation.org: overall redesign and simplification] Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
I suggest to hide non-existent capabilities. Here is two reasons.
* It's logically and easier for using.
* It helps to checkpoint-restore capabilities of tasks, because tasks
can be restored on another kernel, where CAP_LAST_CAP is bigger.
Signed-off-by: Andrew Vagin <avagin@openvz.org> Cc: Andrew G. Morgan <morgan@kernel.org> Reviewed-by: Serge E. Hallyn <serge.hallyn@canonical.com> Cc: Pavel Emelyanov <xemul@parallels.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Eldad Zack [Sat, 3 Nov 2012 00:43:01 +0000 (11:43 +1100)]
simple_strto*: annotate function as obsolete
Update the documentation for simple_strto* to reflect that it has been
obsoleted and advise the usage of kstrto*.
Signed-off-by: Eldad Zack <eldad@fogrefinery.com> Cc: J. Bruce Fields <bfields@fieldses.org> Cc: Joe Perches <joe@perches.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Eldad Zack [Sat, 3 Nov 2012 00:43:01 +0000 (11:43 +1100)]
kstrto*: add documentation
As Bruce Fields pointed out, kstrto* is currently lacking kerneldoc
comments. This patch adds kerneldoc comments to common variants of
kstrto*: kstrto(u)l, kstrto(u)ll and kstrto(u)int.
Signed-off-by: Eldad Zack <eldad@fogrefinery.com> Cc: J. Bruce Fields <bfields@fieldses.org> Cc: Joe Perches <joe@perches.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Namjae Jeon [Sat, 3 Nov 2012 00:43:00 +0000 (11:43 +1100)]
fat: add mutex lock to fat_build_inode
fat_nfs_get_inode() does not hold i_mutex of parent directory. So add
lock to fat_build_inode().
We are making use of fat_build_inode to build the inode using 'i_pos'.
Since, this function is local to FAT and when mounted over NFS. We can
make use of FAT parallely from local NFS Server and mounted from NFS
client. So, in order to avoid race to multiple regeneration for the
same 'i_pos' - we have introduced this locking.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Ravishankar N <ravi.n1@samsung.com> Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: "J. Bruce Fields" <bfields@fieldses.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Namjae Jeon [Sat, 3 Nov 2012 00:43:00 +0000 (11:43 +1100)]
fat: move fat_i_pos_read to fat.h
Originally, fat_i_pos_read() was a static inline function in inode.c. The
static keyword was removed so that it could be accessed from other files.
However it is better to make it a static inline function in fat.h as
suggested by Ogawa.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Ravishankar N <ravi.n1@samsung.com> Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: "J. Bruce Fields" <bfields@fieldses.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Namjae Jeon [Sat, 3 Nov 2012 00:42:59 +0000 (11:42 +1100)]
fat: restructure export operations
Define two nfs export_operation structures,one for 'stale_rw' mounts and
the other for 'nostale_ro'.The former uses the generic export_encode_fh
function to encode file handle, while the latter uses fat_encode_fh().
Since inode number is not needed for nostale_ro, remove it from struct
fat_fid and repack other needed info viz. i_pos and i_generation.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Ravishankar N <ravi.n1@samsung.com> Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: "J. Bruce Fields" <bfields@fieldses.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Namjae Jeon [Sat, 3 Nov 2012 00:42:59 +0000 (11:42 +1100)]
fat: remove parent_logstart check in fat_get_parent
The root directory inode is added to the directory hash table in
fat_attach when mounted with nfs option. Since root dentry never expires
until umount, fat_dget never fails to return the root inode for
subdirectories of root inode.i.e., parent_logstart cannot be zero.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Ravishankar N <ravi.n1@samsung.com> Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: "J. Bruce Fields" <bfields@fieldses.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Namjae Jeon [Sat, 3 Nov 2012 00:42:58 +0000 (11:42 +1100)]
fat (exportfs): rebuild directory-inode if fat_dget() fails
This patch enables rebuilding of directory inodes which are not present in
the cache.This is done by traversing the disk clusters to find the
directory entry of the parent directory and using its i_pos to build the
inode.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Ravishankar N <ravi.n1@samsung.com> Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: "J. Bruce Fields" <bfields@fieldses.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Andrew Morton [Sat, 3 Nov 2012 00:42:58 +0000 (11:42 +1100)]
fat-exportfs-rebuild-inode-if-ilookup-fails-fix
fix warnings/types
fs/fat/nfs.c: In function 'fat_nfs_get_inode':
fs/fat/nfs.c:68: warning: passing argument 3 of 'fat_get_blknr_offset' from incompatible pointer type
fs/fat/fat.h:218: note: expected 'sector_t *' but argument is of type 'loff_t *'
fs/fat/inode.c: In function '__fat_write_inode':
fs/fat/inode.c:630: warning: passing argument 3 of 'fat_get_blknr_offset' from incompatible pointer type
fs/fat/fat.h:218: note: expected 'sector_t *' but argument is of type 'loff_t *'
Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Amit Sahrawat <a.sahrawat@samsung.com> Cc: Namjae Jeon <namjae.jeon@samsung.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Ravishankar N <ravi.n1@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Namjae Jeon [Sat, 3 Nov 2012 00:42:58 +0000 (11:42 +1100)]
fat (exportfs): rebuild inode if ilookup() fails
Assign i_pos to kstat->ino and re-introduce fat_encode_fh() and include
i_pos value in the file handle.Use the i_pos value to find the directory
entry of the inode and subsequently rebuild the inode if the cache lookups
fail.
Since this involves accessing the FAT media, it is better to do this only
if the 'nfs' mount option is enabled with nostale_ro. Also introduce a
helper fat_get_blknr_offset() for use in __fat_write_inode() and
fat_nfs_get_inode()
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Ravishankar N <ravi.n1@samsung.com> Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: "J. Bruce Fields" <bfields@fieldses.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Namjae Jeon [Sat, 3 Nov 2012 00:42:57 +0000 (11:42 +1100)]
fat: modify nfs mount option
This patchset eliminates the client side ESTALE errors when a FAT
partition exported over NFS has its dentries evicted from the cache.
One of the reasons for this error is lack of permanent inode numbers on
FAT which makes it difficult to construct persistent file handles. This
can be overcome by using fat_encode_fh() that include i_pos in file
handle.
Once the i_pos is available, it is only a matter of reading the directory
entries from the disk clusters to locate the matching entry and rebuild
the corresponding inode.
We reached the conclusion support stable inode's read-only export first
after discussing with OGAWA and Bruce. And will make it writable with
some operation(unlink and rename) limitation next time.
This patch:
Provide two possible values 'stale_rw' and 'nostale_ro' for the -o nfs
mount option. The first one allows all file operations but does not
reduce ESTALE errors on memory constrained systems. The second one
eliminates ESTALE errors but mounts the filesystem as read-only. Not
specifying a value defaults to 'stale_rw'.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Ravishankar N <ravi.n1@samsung.com> Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: "J. Bruce Fields" <bfields@fieldses.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
hfsplus: code style fixes - reworked support of extended attributes
This patch fixes code style issues:
1. Rephrase comment.
2. Fix multiline comment style.
3. The hfsplus_alloc_attr_entry() was corrected.
4. The hfsplus_unistr and hfsplus_attr_unistr structures were declared
independently.
Signed-off-by: Vyacheslav Dubeyko <slava@dubeyko.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
hfsplus: add on-disk layout declarations related to attributes tree
Current mainline implementation of hfsplus file system driver treats as
extended attributes only two fields (fdType and fdCreator) of user_info
field in file description record (struct hfsplus_cat_file). It is
possible to get or set only these two fields as extended attributes. But
HFS+ treats as com.apple.FinderInfo extended attribute an union of
user_info and finder_info fields as for file (struct hfsplus_cat_file) as
for folder (struct hfsplus_cat_folder). Moreover, current mainline
implementation of hfsplus file system driver doesn't support special
metadata file - attributes tree.
Mac OS X 10.4 and later support extended attributes by making use of the
HFS+ filesystem Attributes file B*-tree feature which allows for named
forks. Mac OS X supports only inline extended attributes, limiting their
size to 3802 bytes. Any regular file may have a list of extended
attributes. HFS+ supports an arbitrary number of named forks. Each
attribute is denoted by a name and the associated data. The name is a
null-terminated Unicode string. It is possible to list, to get, to set,
and to remove extended attributes from files or directories.
It exists some peculiarity during getting of extended attributes list by
means of getfattr utility. The getfattr utility expects prefix "user."
before any extended attribute's name. So, it ignores any names that don't
contained such prefix. Such behavior of getfattr utility results in
unexpected empty output of extended attributes list even in the case when
file (or folder) contains extended attributes. It needs to use empty
string as regular expression pattern for names matching (getfattr
--match="").
For support of extended attributes in HFS+:
1. It was added necessary on-disk layout declarations related to
Attributes tree into hfsplus_raw.h file.
2. It was added attributes.c file with implementation of functionality
of manipulation by records in Attributes tree.
3. It was reworked hfsplus_listxattr, hfsplus_getxattr,
hfsplus_setxattr functions in ioctl.c. Moreover, it was added
hfsplus_removexattr method.
This patch:
Add all neccessary on-disk layout declarations related to attributes
file.
Signed-off-by: Vyacheslav Dubeyko <slava@dubeyko.com> Reported-by: Hin-Tak Leung <htl10@users.sourceforge.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Cc: Jan Kara <jack@suse.cz> Tested-by: Hin-Tak Leung <htl10@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Roland Stigge [Sat, 3 Nov 2012 00:42:55 +0000 (11:42 +1100)]
ARM: mach-imx: support for DryIce RTC in i.MX53
Enable support for i.MX53 in addition to i.MX25 by providing a dummy clock
on i.MX53 since this one doesn't have a separate clock for internal RTC
but the driver requests one.
Signed-off-by: Roland Stigge <stigge@antcom.de> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Sascha Hauer <kernel@pengutronix.de> Cc: Russell King <linux@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Roland Stigge [Sat, 3 Nov 2012 00:42:54 +0000 (11:42 +1100)]
drivers/rtc/rtc-imxdi.c: add devicetree support
Add device tree support to the rtc-imxdi driver.
Signed-off-by: Roland Stigge <stigge@antcom.de> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Sascha Hauer <kernel@pengutronix.de> Cc: Russell King <linux@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Roland Stigge [Sat, 3 Nov 2012 00:42:54 +0000 (11:42 +1100)]
drivers/rtc/rtc-imxdi: support for i.MX53
Enable support for i.MX53 in addition to i.MX25 by enabling the driver on
ARCH_MXC generally.
Signed-off-by: Roland Stigge <stigge@antcom.de> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Sascha Hauer <kernel@pengutronix.de> Cc: Russell King <linux@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
OMAP1 RTC driver is used in multiple devices like, OMAPL138 and AM33XX.
Driver currently doesn't handle any clocks, which may be right for OMAP1
architecture but in case of AM33XX, the clock/module needs to be enabled
in order to access the registers.
So convert this driver to runtime pm, which internally handles rest.
[afzal@ti.com: handle error path] Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com> Signed-off-by: Afzal Mohammed <afzal@ti.com> Acked-by: Sekhar Nori <nsekhar@ti.com> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Sekhar Nori <nsekhar@ti.com> Cc: Kevin Hilman <khilman@ti.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Daniel Mack <zonque@gmail.com> Cc: Vaibhav Hiremath <hvaibhav@ti.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Afzal Mohammed [Sat, 3 Nov 2012 00:42:53 +0000 (11:42 +1100)]
rtc: omap: depend on am33xx
rtc-omap driver can be reused for AM33xx RTC. Provide dependency in
Kconfig.
Signed-off-by: Afzal Mohammed <afzal@ti.com> Acked-by: Sekhar Nori <nsekhar@ti.com> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Sekhar Nori <nsekhar@ti.com> Cc: Kevin Hilman <khilman@ti.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Daniel Mack <zonque@gmail.com> Cc: Vaibhav Hiremath <hvaibhav@ti.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Afzal Mohammed [Sat, 3 Nov 2012 00:42:53 +0000 (11:42 +1100)]
rtc: omap: dt support
Enhance rtc-omap driver with DT capability
Signed-off-by: Afzal Mohammed <afzal@ti.com> Acked-by: Sekhar Nori <nsekhar@ti.com> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Sekhar Nori <nsekhar@ti.com> Cc: Kevin Hilman <khilman@ti.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Daniel Mack <zonque@gmail.com> Cc: Vaibhav Hiremath <hvaibhav@ti.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Afzal Mohammed [Sat, 3 Nov 2012 00:42:53 +0000 (11:42 +1100)]
ARM: davinci: remove rtc kicker release
rtc-omap driver is now capable of handling kicker mechanism, hence remove
kicker handling at platform level, instead provide proper device name so
that driver can handle kicker mechanism by itself
Signed-off-by: Afzal Mohammed <afzal@ti.com> Acked-by: Sekhar Nori <nsekhar@ti.com> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Sekhar Nori <nsekhar@ti.com> Cc: Kevin Hilman <khilman@ti.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Daniel Mack <zonque@gmail.com> Cc: Vaibhav Hiremath <hvaibhav@ti.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Afzal Mohammed [Sat, 3 Nov 2012 00:42:53 +0000 (11:42 +1100)]
rtc: omap: kicker mechanism support
OMAP RTC IP can have kicker feature. This prevents spurious writes to
register. To write to registers kicker lock has to be released.
Procedure to do it as follows,
1. write to kick0 register, 0x83e70b13
2. write to kick1 register, 0x95a4f1e0
Writing value other than 0x83e70b13 to kick0 enables write locking, more
details about kicker mechanism can be found in section 20.3.3.5.3 of
AM335X TRM @www.ti.com/am335x
Here id table information is added and is used to distinguish those that
require kicker handling and the ones that doesn't need it. There are more
features in the newer IP's compared to legacy ones other than kicker,
which driver currently doesn't handle, supporting additional features
would be easier with the addition of id table.
Older IP (of OMAP1) doesn't have revision register as per TRM, so revision
register can't be relied always to find features, hence id table is being
used.
While at it, replace __raw_writeb/__raw_readb with writeb/readb; this
driver is used on ARMv7 (AM335X SoC)
Signed-off-by: Afzal Mohammed <afzal@ti.com> Acked-by: Sekhar Nori <nsekhar@ti.com> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Sekhar Nori <nsekhar@ti.com> Cc: Kevin Hilman <khilman@ti.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Daniel Mack <zonque@gmail.com> Cc: Vaibhav Hiremath <hvaibhav@ti.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Alan Cox [Sat, 3 Nov 2012 00:42:52 +0000 (11:42 +1100)]
binfmt_elf: fix corner case kfree of uninitialized data
If elf_core_dump() is called and fill_note_info() fails in the kmalloc()
then it returns 0 but has not yet initialised all the needed fields. As a
result we do a kfree(randomness) after correctly skipping the thread data.
Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Paton J. Lewis [Sat, 3 Nov 2012 00:42:52 +0000 (11:42 +1100)]
epoll: support for disabling items, and a self-test app
It is not currently possible to reliably delete epoll items when using the
same epoll set from multiple threads. After calling epoll_ctl with
EPOLL_CTL_DEL, another thread might still be executing code related to an
event for that epoll item (in response to epoll_wait). Therefore the
deleting thread does not know when it is safe to delete resources
pertaining to the associated epoll item because another thread might be
using those resources.
The deleting thread could wait an arbitrary amount of time after calling
epoll_ctl with EPOLL_CTL_DEL and before deleting the item, but this is
inefficient and could result in the destruction of resources before
another thread is done handling an event returned by epoll_wait.
This patch enhances epoll_ctl to support EPOLL_CTL_DISABLE, which disables
an epoll item. If epoll_ctl returns -EBUSY in this case, then another
thread may handling a return from epoll_wait for this item. Otherwise if
epoll_ctl returns 0, then it is safe to delete the epoll item. This
allows multiple threads to use a mutex to determine when it is safe to
delete an epoll item and its associated resources, which allows epoll
items to be deleted both efficiently and without error in a multi-threaded
environment. Note that EPOLL_CTL_DISABLE is only useful in conjunction
with EPOLLONESHOT, and using EPOLL_CTL_DISABLE on an epoll item without
EPOLLONESHOT returns -EINVAL.
This patch also adds a new test_epoll self-test program to both
demonstrate the need for this feature and test it.
Signed-off-by: Paton J. Lewis <palewis@adobe.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Jason Baron <jbaron@redhat.com> Cc: Paul Holland <pholland@adobe.com> Cc: Davide Libenzi <davidel@xmailserver.org> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Joe Perches [Sat, 3 Nov 2012 00:42:51 +0000 (11:42 +1100)]
checkpatch: warn on unnecessary line continuations
When the previous line is not a line continuation and the current line has
a line continuation but is not a #define, emit a warning.
Signed-off-by: Joe Perches <joe@perches.com> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Andy Whitcroft <apw@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This function is used by sparc, powerpc tile and arm64 for compat support.
The patch adds a generic implementation with a wrapper for PowerPC to do
the u32->int sign extension.
The reason for a single patch covering powerpc, tile, sparc and arm64 is
to keep it bisectable, otherwise kernel building may fail with mismatched
function declarations.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Chris Metcalf <cmetcalf@tilera.com> [for tile] Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Andy Shevchenko [Sat, 3 Nov 2012 00:42:48 +0000 (11:42 +1100)]
lib: dynamic_debug: use kbasename()
Remove the custom implementation of the functionality similar to kbasename().
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Jason Baron <jbaron@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Andy Shevchenko [Sat, 3 Nov 2012 00:42:48 +0000 (11:42 +1100)]
string: introduce helper to get base file name from given path
There are several places in the kernel that use functionality like
basename(3) with the exception: in case of '/foo/bar/' we expect to get an
empty string. Let's do it common helper for them.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Jason Baron <jbaron@redhat.com> Cc: YAMANE Toshiaki <yamanetoshi@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
WARNING: drivers/video/backlight/built-in.o(.data+0x110): Section mismatch in reference from the variable ep93xxbl_driver to the
function .init.text:ep93xxbl_probe()
The variable ep93xxbl_driver references
the function __init ep93xxbl_probe()
If the reference is valid then annotate the
variable with __init* or __refdata (see linux/init.h) or name the variable:
*_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Axel Lin [Sat, 3 Nov 2012 00:42:47 +0000 (11:42 +1100)]
drivers/video/backlight/lm3639_bl.c: fix up world writable sysfs file
We don't need the sysfs file to be world writable or group writable.
This file is write-only, change it to S_IWUSR (0200).
Signed-off-by: Axel Lin <axel.lin@ingics.com> Acked-by: "G.Shark Jeong" <gshark.jeong@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jingoo Han [Sat, 3 Nov 2012 00:42:46 +0000 (11:42 +1100)]
drivers/video/backlight/max8925_bl.c: drop devm_kfree of devm_kzalloc'd data
devm_kfree() allocates memory that is released when a driver detaches.
Thus, there is no reason to explicitly call devm_kfree in probe or remove
functions.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jingoo Han [Sat, 3 Nov 2012 00:42:46 +0000 (11:42 +1100)]
drivers/video/backlight/88pm860x_bl.c: drop devm_kfree of devm_kzalloc'd data
devm_kfree() allocates memory that is released when a driver detaches.
Thus, there is no reason to explicitly call devm_kfree() in probe or remove
functions.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add 'const' to static array that was missing it in its definition. Also,
'const' is added to ili9320_write_regs(), because it is called by
vgg2432a4 driver.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Ben Dooks <ben-linux@fluff.org> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add 'const' to static array that was missing it in its definition.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Eric Miao <eric.y.miao@gmail.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add 'const' to static array that was missing it in its definition.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Acked-by: Marek Vasut <marex@denx.de> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The mutex for accessing lp855x registers is used in case of the user-space
interaction. When the brightness is changed via sysfs, the mutex is
required. But the backlight class device already provides it. Thus, the
lp855x mutex is unnecessary.
Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com> Cc: Thierry Reding <thierry.reding@avionic-design.de> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Bryan Wu <bryan.wu@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Kim, Milo [Sat, 3 Nov 2012 00:42:43 +0000 (11:42 +1100)]
drivers/video/backlight/lp855x_bl.c: use generic PWM functions
The LP855x family devices support the PWM input for the backlight control.
Period of the PWM is configurable in the platform side. Platform
specific functions are unnecessary anymore because generic PWM functions
are used inside the driver.
(PWM input mode)
To set the brightness, new lp855x_pwm_ctrl() is used.
If a PWM device is not allocated, devm_pwm_get() is called.
The PWM consumer name is from the chip name such as 'lp8550' and 'lp8556'.
To get the brightness value, no additional handling is required.
Just the value of 'props.brightness' is returned.
If the PWM driver is not ready while initializing the LP855x driver, it's
OK. The PWM device can be retrieved later, when the brightness value is
changed.
Documentation is updated with an example.
Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com> Cc: Thierry Reding <thierry.reding@avionic-design.de> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Bryan Wu <bryan.wu@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jingoo Han [Sat, 3 Nov 2012 00:42:43 +0000 (11:42 +1100)]
backlight: tosa: use devm_gpio_request_one
By using devm_gpio_request_one it is possible to set the direction and
initial value in one shot. Thus, using devm_gpio_request_one can make the
code simpler.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Dmitry Baryshkov <dbaryshkov@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jingoo Han [Sat, 3 Nov 2012 00:42:43 +0000 (11:42 +1100)]
backlight: lms283gf05: use devm_gpio_request_one
By using devm_gpio_request_one it is possible to set the direction
and initial value in one shot. Thus, using devm_gpio_request_one
can make the code simpler.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Richard Purdie <rpurdie@rpsys.net> Acked-by: Marek Vasut <marex@denx.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jingoo Han [Sat, 3 Nov 2012 00:42:41 +0000 (11:42 +1100)]
backlight: locomolcd: fix checkpatch error and warning
This patch fixes the checkpatch error and warning as below:
WARNING: line over 80 characters
WARNING: space prohibited between function name and open parenthesis '('
ERROR: trailing statements should be on next line
Also, long comments are fixed for the preferred style and
unnecessary lines are removed.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jingoo Han [Sat, 3 Nov 2012 00:42:39 +0000 (11:42 +1100)]
backlight: ili9320: fix checkpatch error and warning
This patch fixes the checkpatch error and warning as below:
WARNING: please, no space before tabs
WARNING: please, no spaces at the start of a line
WARNING: EXPORT_SYMBOL(foo); should immediately follow its function/variable
WARNING: braces {} are not necessary for single statement blocks
ERROR: code indent should use tabs where possible
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jingoo Han [Sat, 3 Nov 2012 00:42:39 +0000 (11:42 +1100)]
backlight: hp680_bl: fix checkpatch error and warning
This patch fixes the checkpatch error and warning as below:
WARNING: please, no space before tabs
WARNING: please, no spaces at the start of a line
ERROR: do not initialise statics to 0 or NULL
ERROR: code indent should use tabs where possible
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jingoo Han [Sat, 3 Nov 2012 00:42:37 +0000 (11:42 +1100)]
backlight: da903x_bl: use dev_get_drvdata() instead of platform_get_drvdata()
dev_get_drvdata() can be used instead of platform_get_drvdata()
to make the code smaller.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Mike Rapoport <mike@compulab.co.il> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Matthew Leach [Sat, 3 Nov 2012 00:42:36 +0000 (11:42 +1100)]
include/linux/init.h: use the stringify operator for the __define_initcall macro
Currently the __define_initcall() macro takes three arguments, fn, id and
level. The level argument is exactly the same as the id argument but
wrapped in quotes. To overcome this need to specify three arguments to
the __define_initcall macro, where one argument is the stringification of
another, we can just use the stringification macro instead.
Signed-off-by: Matthew Leach <matthew@mattleach.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Wen Congyang [Sat, 3 Nov 2012 00:42:36 +0000 (11:42 +1100)]
Documentation/kernel-parameters.txt: update mem= option's spec according to its implementation
Current mem= implementation seems buggy because the specification and
implementation don't match. The current mem= has been working for many
years and it's not buggy - it works as expected. So we should update the
specification.
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
PBM generated with current tools do not have a whitespace between the
digits. Therefore the pnmtologo tool fails to gernerate the required
C-Array for these images. This patch fixes that behaviour and can handle
both 'old style' and 'new style' PBM files.
Signed-off-by: Andreas Bießmann <andreas@biessmann.de> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Wanpeng Li [Sat, 3 Nov 2012 00:42:35 +0000 (11:42 +1100)]
mm/memblock: reduce overhead in binary search
When checking that the indicated address belongs to the memory region, the
memory regions are checked one by one through a binary search, which will
be time consuming.
If the indicated address isn't in the memory region, then we needn't do
the time-consuming search. Add a check on the indicated address for that
purpose.
Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Gavin Shan <shangw@linux.vnet.ibm.com> Cc: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Shaohua Li [Sat, 3 Nov 2012 00:42:35 +0000 (11:42 +1100)]
swap: add a simple detector for inappropriate swapin readahead
The swapin readahead does a blind readahead whether or not the swapin is
sequential. This is ok for harddisk because large reads have relatively
small costs and if the readahead pages are unneeded they can be reclaimed
easily. But for SSD devices large reads are more expensive than small
one. If readahead pages are unneeded, reading them in caused significant
overhead
This patch addes a simple random read detection similar to file mmap
readahead. If a random read is detected, swapin readahead will be
skipped. This improves a lot for a swap workload with random IO in a fast
SSD.
I run anonymous mmap write micro benchmark, which will triger swapin/swapout.
For both harddisk and SSD, the randwrite swap workload run time is reduced
significantly. Sequential write swap workload hasn't chanage.
Interestingly, the randwrite harddisk test is improved too. This might be
because swapin readahead needs to allocate extra memory, which further
tights memory pressure, so more swapout/swapin.
Signed-off-by: Shaohua Li <shli@fusionio.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Michal Hocko [Sat, 3 Nov 2012 00:42:34 +0000 (11:42 +1100)]
drop_caches: add some documentation and info message
I would like to resurrect Dave's patch. The last time it was posted was
here https://lkml.org/lkml/2010/9/16/250 and there didn't seem to be any
strong opposition.
Kosaki was worried about possible excessive logging when somebody drops
caches too often (but then he claimed he didn't have a strong opinion on
that) but I would say opposite. If somebody does that then I would really
like to know that from the log when supporting a system because it almost
for sure means that there is something fishy going on. It is also worth
mentioning that only root can write drop caches so this is not an flooding
attack vector.
I am bringing that up again because this can be really helpful when
chasing strange performance issues which (surprise surprise) turn out to
be related to artificially dropped caches done because the admin thinks
this would help...
I have just refreshed the original patch on top of the current mm tree
but I could live with KERN_INFO as well if people think that KERN_NOTICE
is too hysterical.
: From: Dave Hansen <dave@linux.vnet.ibm.com>
: Date: Fri, 12 Oct 2012 14:30:54 +0200
:
: There is plenty of anecdotal evidence and a load of blog posts
: suggesting that using "drop_caches" periodically keeps your system
: running in "tip top shape". Perhaps adding some kernel
: documentation will increase the amount of accurate data on its use.
:
: If we are not shrinking caches effectively, then we have real bugs.
: Using drop_caches will simply mask the bugs and make them harder
: to find, but certainly does not fix them, nor is it an appropriate
: "workaround" to limit the size of the caches.
:
: It's a great debugging tool, and is really handy for doing things
: like repeatable benchmark runs. So, add a bit more documentation
: about it, and add a little KERN_NOTICE. It should help developers
: who are chasing down reclaim-related bugs.
[mhocko@suse.cz: refreshed to current -mm tree] Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Michal Hocko <mhocko@suse.cz> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Glauber Costa [Sat, 3 Nov 2012 00:42:33 +0000 (11:42 +1100)]
slub: slub-specific propagation changes
SLUB allows us to tune a particular cache behavior with sysfs-based
tunables. When creating a new memcg cache copy, we'd like to preserve any
tunables the parent cache already had.
This can be done by tapping into the store attribute function provided by
the allocator. We of course don't need to mess with read-only fields.
Since the attributes can have multiple types and are stored internally by
sysfs, the best strategy is to issue a ->show() in the root cache, and
then ->store() in the memcg cache.
The drawback of that, is that sysfs can allocate up to a page in buffering
for show(), that we are likely not to need, but also can't guarantee. To
avoid always allocating a page for that, we can update the caches at store
time with the maximum attribute size ever stored to the root cache. We
will then get a buffer big enough to hold it. The corolary to this, is
that if no stores happened, nothing will be propagated.
It can also happen that a root cache has its tunables updated during
normal system operation. In this case, we will propagate the change to
all caches that are already active.
Signed-off-by: Glauber Costa <glommer@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Frederic Weisbecker <fweisbec@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: JoonSoo Kim <js1304@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Michal Hocko <mhocko@suse.cz> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Rik van Riel <riel@redhat.com> Cc: Suleiman Souhlal <suleiman@google.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Glauber Costa [Sat, 3 Nov 2012 00:42:33 +0000 (11:42 +1100)]
slab: propagate tunable values
SLAB allows us to tune a particular cache behavior with tunables. When
creating a new memcg cache copy, we'd like to preserve any tunables the
parent cache already had.
This could be done by an explicit call to do_tune_cpucache() after the
cache is created. But this is not very convenient now that the caches are
created from common code, since this function is SLAB-specific.
Another method of doing that is taking advantage of the fact that
do_tune_cpucache() is always called from enable_cpucache(), which is
called at cache initialization. We can just preset the values, and then
things work as expected.
It can also happen that a root cache has its tunables updated during
normal system operation. In this case, we will propagate the change to
all caches that are already active.
This change will require us to move the assignment of root_cache in
memcg_params a bit earlier. We need this to be already set - which
memcg_kmem_register_cache will do - when we reach __kmem_cache_create()
Signed-off-by: Glauber Costa <glommer@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Frederic Weisbecker <fweisbec@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: JoonSoo Kim <js1304@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Michal Hocko <mhocko@suse.cz> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Rik van Riel <riel@redhat.com> Cc: Suleiman Souhlal <suleiman@google.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Glauber Costa [Sat, 3 Nov 2012 00:42:33 +0000 (11:42 +1100)]
memcg: aggregate memcg cache values in slabinfo
When we create caches in memcgs, we need to display their usage
information somewhere. We'll adopt a scheme similar to /proc/meminfo,
with aggregate totals shown in the global file, and per-group information
stored in the group itself.
For the time being, only reads are allowed in the per-group cache.
Signed-off-by: Glauber Costa <glommer@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Frederic Weisbecker <fweisbec@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: JoonSoo Kim <js1304@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Michal Hocko <mhocko@suse.cz> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Rik van Riel <riel@redhat.com> Cc: Suleiman Souhlal <suleiman@google.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Glauber Costa [Sat, 3 Nov 2012 00:42:32 +0000 (11:42 +1100)]
memcg/sl[au]b: shrink dead caches
This means that when we destroy a memcg cache that happened to be empty,
those caches may take a lot of time to go away: removing the memcg
reference won't destroy them - because there are pending references, and
the empty pages will stay there, until a shrinker is called upon for any
reason.
In this patch, we will call kmem_cache_shrink() for all dead caches that
cannot be destroyed because of remaining pages. After shrinking, it is
possible that it could be freed. If this is not the case, we'll schedule
a lazy worker to keep trying.
Signed-off-by: Glauber Costa <glommer@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Frederic Weisbecker <fweisbec@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: JoonSoo Kim <js1304@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Michal Hocko <mhocko@suse.cz> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Rik van Riel <riel@redhat.com> Cc: Suleiman Souhlal <suleiman@google.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Glauber Costa [Sat, 3 Nov 2012 00:42:32 +0000 (11:42 +1100)]
memcg/sl[au]b: track all the memcg children of a kmem_cache
This enables us to remove all the children of a kmem_cache being
destroyed, if for example the kernel module it's being used in gets
unloaded. Otherwise, the children will still point to the destroyed
parent.
Signed-off-by: Suleiman Souhlal <suleiman@google.com> Signed-off-by: Glauber Costa <glommer@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Frederic Weisbecker <fweisbec@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: JoonSoo Kim <js1304@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Michal Hocko <mhocko@suse.cz> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Rik van Riel <riel@redhat.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Glauber Costa [Sat, 3 Nov 2012 00:42:32 +0000 (11:42 +1100)]
memcg: destroy memcg caches
Implement destruction of memcg caches. Right now, only caches where our
reference counter is the last remaining are deleted. If there are any
other reference counters around, we just leave the caches lying around
until they go away.
When that happens, a destruction function is called from the cache code.
Caches are only destroyed in process context, so we queue them up for
later processing in the general case.
Signed-off-by: Glauber Costa <glommer@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Frederic Weisbecker <fweisbec@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: JoonSoo Kim <js1304@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Michal Hocko <mhocko@suse.cz> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Rik van Riel <riel@redhat.com> Cc: Suleiman Souhlal <suleiman@google.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Glauber Costa [Sat, 3 Nov 2012 00:42:31 +0000 (11:42 +1100)]
sl[au]b: allocate objects from memcg cache
We are able to match a cache allocation to a particular memcg. If the
task doesn't change groups during the allocation itself - a rare event,
this will give us a good picture about who is the first group to touch a
cache page.
This patch uses the now available infrastructure by calling
memcg_kmem_get_cache() before all the cache allocations.
Signed-off-by: Glauber Costa <glommer@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Frederic Weisbecker <fweisbec@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: JoonSoo Kim <js1304@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Michal Hocko <mhocko@suse.cz> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Rik van Riel <riel@redhat.com> Cc: Suleiman Souhlal <suleiman@google.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Glauber Costa [Sat, 3 Nov 2012 00:42:31 +0000 (11:42 +1100)]
sl[au]b: always get the cache from its page in kmem_cache_free()
struct page already has this information. If we start chaining caches,
this information will always be more trustworthy than whatever is passed
into the function
Signed-off-by: Glauber Costa <glommer@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Frederic Weisbecker <fweisbec@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: JoonSoo Kim <js1304@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Michal Hocko <mhocko@suse.cz> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Rik van Riel <riel@redhat.com> Cc: Suleiman Souhlal <suleiman@google.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Glauber Costa [Sat, 3 Nov 2012 00:42:31 +0000 (11:42 +1100)]
memcg: skip memcg kmem allocations in specified code regions
Create a mechanism that skip memcg allocations during certain pieces of
our core code. It basically works in the same way as
preempt_disable()/preempt_enable(): By marking a region under which all
allocations will be accounted to the root memcg.
We need this to prevent races in early cache creation, when we
allocate data using caches that are not necessarily created already.
Signed-off-by: Glauber Costa <glommer@parallels.com>
yCc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Frederic Weisbecker <fweisbec@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: JoonSoo Kim <js1304@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Michal Hocko <mhocko@suse.cz> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Rik van Riel <riel@redhat.com> Cc: Suleiman Souhlal <suleiman@google.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Glauber Costa [Sat, 3 Nov 2012 00:42:30 +0000 (11:42 +1100)]
memcg: infrastructure to match an allocation to the right cache
The page allocator is able to bind a page to a memcg when it is allocated.
But for the caches, we'd like to have as many objects as possible in a
page belonging to the same cache.
This is done in this patch by calling memcg_kmem_get_cache in the
beginning of every allocation function. This routing is patched out by
static branches when kernel memory controller is not being used.
It assumes that the task allocating, which determines the memcg in the
page allocator, belongs to the same cgroup throughout the whole process.
Misacounting can happen if the task calls memcg_kmem_get_cache() while
belonging to a cgroup, and later on changes. This is considered
acceptable, and should only happen upon task migration.
Before the cache is created by the memcg core, there is also a possible
imbalance: the task belongs to a memcg, but the cache being allocated from
is the global cache, since the child cache is not yet guaranteed to be
ready. This case is also fine, since in this case the GFP_KMEMCG will not
be passed and the page allocator will not attempt any cgroup accounting.
Signed-off-by: Glauber Costa <glommer@parallels.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Frederic Weisbecker <fweisbec@redhat.com> Cc: Greg Thelen <gthelen@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: JoonSoo Kim <js1304@gmail.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Michal Hocko <mhocko@suse.cz> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Rik van Riel <riel@redhat.com> Cc: Suleiman Souhlal <suleiman@google.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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