Steven Rostedt [Wed, 29 Jul 2009 04:21:22 +0000 (00:21 -0400)]
sched: Check for pushing rt tasks after all scheduling
The current method for pushing RT tasks after scheduling only
happens after a context switch. But we found cases where a task
is set up on a run queue to be pushed but the push never
happens because the schedule chooses the same task.
This bug was found with the help of Gregory Haskins and the use
of ftrace (trace_printk). It tooks several days for both of us
analyzing the code and the trace output to find this.
Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090729042526.205923666@goodmis.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
In order to avoid starvation of newly placed tasks, we never
quite set the share of an empty cpu group-task to 0, but
instead we set it as if there's a single NICE-0 task present.
If however we actually set this in cfs_rq[cpu]->shares, that
means the total shares for that group will be slightly inflated
every time we balance, causing the observed unfairness.
Fix this by setting cfs_rq[cpu]->shares to 0 but actually
setting the effective weight of the related se to the inflated
number.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1248696557.6987.1615.camel@twins> Signed-off-by: Ingo Molnar <mingo@elte.hu>
sched: Fix race in cpupri introduced by cpumask_var changes
Background:
Several race conditions in the scheduler have cropped up
recently, which Steven and I have tracked down using ftrace.
The most recent one turns out to be a race in how the scheduler
determines a suitable migration target for RT tasks, introduced
recently with commit:
The original design of cpupri allowed lockless readers to
quickly determine a best-estimate target. Races between the
pri_active bitmap and the vec->mask were handled in the
original code because we would detect and return "0" when this
occured. The design was predicated on the *effective*
atomicity (*) of caching the result of cpus_and() between the
cpus_allowed and the vec->mask.
Commit 68e74568 changed the behavior such that vec->mask is
accessed multiple times. This introduces a subtle race, the
result of which means we can have a result that returns "1",
but with an empty bitmap.
*) yes, we know cpus_and() is not a locked operator across the
entire composite array, but it is implicitly atomic on a
per-word basis which is all the design required to work.
Implementation:
Rather than forgoing the lockless design, or reverting to a
stack-based cpumask_t, we simply check for when the race has
been encountered and continue processing in the event that the
race is hit. This renders the removal race as if the priority
bit had been atomically cleared as well, and allows the
algorithm to execute correctly.
Signed-off-by: Gregory Haskins <ghaskins@novell.com> CC: Rusty Russell <rusty@rustcorp.com.au> CC: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090730145728.25226.92769.stgit@dev.haskins.net> Signed-off-by: Ingo Molnar <mingo@elte.hu>
The might_sleep() test inside cond_resched_lock() assumes the
spinlock is held and then preemption is disabled. This is true
with CONFIG_PREEMPT but the preempt_count() doesn't change
otherwise.
Check by starting from the appropriate preempt offset depending
on the config.
Reported-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1248458723-12146-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
io context: fix ref counting
block: make the end_io functions be non-GPL exports
block: fix improper kobject release in blk_integrity_unregister
block: always assign default lock to queues
mg_disk: Add missing ready status check on mg_write()
mg_disk: fix issue with data integrity on error in mg_write()
mg_disk: fix reading invalid status when use polling driver
mg_disk: remove prohibited sleep operation
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/drzeus/mmc
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/drzeus/mmc:
mmc: orphan subsystem
imxmmc: Remove unnecessary semicolons
cb710: use SG_MITER_TO_SG/SG_MITER_FROM_SG
sdhci: use SG_MITER_TO_SG/SG_MITER_FROM_SG
lib/scatterlist: add a flags to signalize mapping direction
the code allready uses flush_kernel_dcache_page(). This patch updates the
driver to the recent sg API changes which require that either SG_MITER_TO_SG
or SG_MITER_FROM_SG is set. SG_MITER_TO_SG calls flush_kernel_dcache_page()
in sg_mitter_stop()
Signed-off-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc> Acked-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: Pierre Ossman <pierre@ossman.eu>
lib/scatterlist: add a flags to signalize mapping direction
sg_miter_start() is currently unaware of the direction of the copy
process (to or from the scatter list). It is important to know the
direction because the page has to be flushed in case the data written
is seen on a different mapping in user land on cache incoherent
architectures.
Signed-off-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc> Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Pierre Ossman <pierre@ossman.eu>
x = \(kmalloc\|kcalloc\|kzalloc\)(...);
... when != x == NULL
when != x != NULL
when != (x || ...)
(
kfree(x)
|
f(...,C,...,x,...)
|
*f(...,x,...)
|
*x->f
)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: Takashi Iwai <tiwai@suse.de>
Eric Sandeen [Fri, 31 Jul 2009 05:02:17 +0000 (00:02 -0500)]
xfs: bump up nr_to_write in xfs_vm_writepage
VM calculation for nr_to_write seems off. Bump it way
up, this gets simple streaming writes zippy again.
To be reviewed again after Jens' writeback changes.
Signed-off-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Eric Sandeen <sandeen@sandeen.net> Cc: Chris Mason <chris.mason@oracle.com> Reviewed-by: Felix Blyakher <felixb@sgi.com> Signed-off-by: Felix Blyakher <felixb@sgi.com>
Eric Sandeen [Mon, 27 Jul 2009 02:52:01 +0000 (21:52 -0500)]
xfs: reduce bmv_count in xfs_vn_fiemap
commit 6321e3ed2acf3ee9643cdd403e1c88605d7944ba caused
the full bmv_count's worth of getbmapx structures to get
allocated; telling it to do MAXEXTNUM was a bit insane,
resulting in ENOMEM every time.
Chop it down to something reasonable, the number of slots
in the caller's input buffer. If this is too large the
caller may get ENOMEM but the reason should not be a
mystery, and they can try again with something smaller.
We add 1 to the value because in the normal getbmap
world, bmv_count includes the header and xfs_getbmap does:
Signed-off-by: Eric Sandeen <sandeen@sandeen.net> Reviewed-by: Olaf Weber <olaf@sgi.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Felix Blyakher <felixb@sgi.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
Btrfs: be more polite in the async caching threads
Btrfs: preserve commit_root for async caching
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx:
dmaengine: at_hdmac: add DMA slave transfers
dmaengine: at_hdmac: new driver for the Atmel AHB DMA Controller
dmaengine: dmatest: correct thread_count while using multiple thread per channel
dmaengine: dmatest: add a maximum number of test iterations
drivers/dma: Remove unnecessary semicolons
drivers/dma/fsldma.c: Remove unnecessary semicolons
dmaengine: move HIGHMEM64G restriction to ASYNC_TX_DMA
fsldma: do not clear bandwidth control bits on the 83xx controller
fsldma: enable external start for the 83xx controller
fsldma: use PCI Read Multiple command
Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-udf-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-udf-2.6:
udf: Fix loading of VAT inode when drive wrongly reports number of recorded blocks
* git://git.infradead.org/users/cbou/battery-2.6.31:
Add ds2782 battery gas gauge driver
olpc_battery: Ensure that the TRICKLE bit is checked
olpc_battery: Fix up eeprom read function
* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-fixes:
GFS2: remove dcache entries for remote deleted inodes
GFS2: Fix incorrent statfs consistency check
GFS2: Don't put unlikely reclaim candidates on the reclaim list.
GFS2: Don't try and dealloc own inode
GFS2: Fix panic in glock memory shrinker
GFS2: keep statfs info in sync on grows
GFS2: Shrink the shrinker
Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc: Update defconfigs for embedded 6xx/7xxx, 8xx, 8{3,5,6}xxx
powerpc/86xx: Update GE Fanuc sbc310 default configuration
powerpc/86xx: Update defconfig for GE Fanuc's PPC9A
cpm_uart: Don't use alloc_bootmem in cpm_uart_cpm2.c
powerpc/83xx: Fix PCI IO base address on MPC837xE-RDB boards
powerpc/85xx: Don't scan for TBI PHY addresses on MPC8569E-MDS boards
powerpc/85xx: Fix ethernet link detection on MPC8569E-MDS boards
powerpc/mm: Fix SMP issue with MMU context handling code
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
lguest and virtio: cleanup struct definitions to Linux style.
lguest: update commentry
lguest: fix comment style
virtio: refactor find_vqs
virtio: delete vq from list
virtio: fix memory leak on device removal
lguest: fix descriptor corruption in example launcher
lguest: dereferencing freed mem in add_eventfd()
kprobes: Use kernel_text_address() for checking probe address
Use kernel_text_address() for checking probe address instead of
__kernel_text_address(), because __kernel_text_address() returns true
for init functions even after relaseing those functions.
That will hit a BUG() in text_poke().
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jan Kara [Wed, 22 Jul 2009 16:12:17 +0000 (18:12 +0200)]
quota: Silence lockdep on quota_on
Commit d01730d74d2b0155da50d44555001706294014f7 didn't completely fix
the problem since we still take dqio_mutex and i_mutex in the wrong
order. Move taking of i_mutex further down (luckily it's needed only
for updating inode flags) below where dqio_mutex is taken.
Tested-by: Valdis Kletnieks <valdis.kletnieks@vt.edu> Signed-off-by: Jan Kara <jack@suse.cz>
Jan Kara [Tue, 14 Jul 2009 17:30:23 +0000 (19:30 +0200)]
udf: Fix loading of VAT inode when drive wrongly reports number of recorded blocks
VAT inode is located in the last block recorded block of the medium. When the
drive errorneously reports number of recorded blocks, we failed to load the VAT
inode and thus mount the medium. This patch makes kernel try to read VAT inode
from the last block of the device if it is different from the last recorded
block.
Chris Mason [Thu, 30 Jul 2009 14:04:48 +0000 (10:04 -0400)]
Btrfs: be more polite in the async caching threads
The semaphore used by the async caching threads can prevent a
transaction commit, which can make the FS appear to stall. This
releases the semaphore more often when a transaction commit is
in progress.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Yan Zheng [Thu, 30 Jul 2009 13:40:40 +0000 (09:40 -0400)]
Btrfs: preserve commit_root for async caching
The async block group caching code uses the commit_root pointer
to get a stable version of the extent allocation tree for scanning.
This copy of the tree root isn't going to change and it significantly
reduces the complexity of the scanning code.
During a commit, we have a loop where we update the extent allocation
tree root. We need to loop because updating the root pointer in
the tree of tree roots may allocate blocks which may change the
extent allocation tree.
Right now the commit_root pointer is changed inside this loop. It
is more correct to change the commit_root pointer only after all the
looping is done.
Signed-off-by: Yan Zheng <zheng.yan@oracle.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
GFS2: remove dcache entries for remote deleted inodes
When a file is deleted from a gfs2 filesystem on one node, a dcache
entry for it may still exist on other nodes in the cluster. If this
happens, gfs2 will be unable to free this file on disk. Because of this,
it's possible to have a gfs2 filesystem with no files on it and no free
space. With this patch, when a node receives a callback notifying it
that the file is being deleted on another node, it schedules a new
workqueue thread to remove the file's dcache entry.
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Since both linked and unlinked inodes are counted by rgd->rd_dinodes, It
makes no sense to count them with the used data blocks (first check that
I changed), it makes sense to count them with the linked inodes (second
check), and it makes no sense to care if there are more unlinked inodes
than linked ones. This fixes these errors.
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
GFS2: Don't put unlikely reclaim candidates on the reclaim list.
GFS2 was placing far too many glocks on the reclaim list that were not good
candidates for freeing up from cache. These locks would sit there and
repeatedly get scanned to see if they could be reclaimed, wasting a lot
of time when there was memory pressure. This fix does more checks on the
locks to see if they are actually likely to be removable from cache.
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
When searching for unlinked, but still allocated inodes during block
allocation, avoid the block relating to the inode that is doing the
allocation. This fixes a hang caused when an unlinked, but still
open, inode tries to allocate some more blocks and lands up
finding itself during the search for deallocatable inodes.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
It is possible for gfs2_shrink_glock_memory() to check a glock for
demotion
that's in the process of being freed by gfs2_glock_put(). In this case,
gfs2_shrink_glock_memory() will acquire a new reference to this glock,
and
then try to free the glock itself when it drops the refernce. To solve
this, gfs2_shrink_glock_memory() just needs to check if the glock is in
the process of being freed, and if so skip it without ever unlocking the
lru_lock.
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Acked-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
GFS2 wasn't syncing its statfs info on grows. This causes a problem
when you grow the filesystem on multiple nodes. GFS2 would calculate
the new space based on the resource groups (which are always current),
and then assume that the filesystem had grown the from the existing
statfs size. If you grew the filesystem on two different nodes in a
short time, the second node wouldn't see the statfs size change from the
first node, and would assume that it was grown by a larger amount than
it was. When all these changes were synced out, the total fileystem
size would be incorrect (the first grow would be counted twice).
This patch syncs makes GFS2 read in the statfs changes from disk before
a grow, and write them out after the grow, while the master statfs inode
is locked.
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch removes some of the special cases that the shrinker
was trying to deal with. As a result we leave fewer items on
the list and none at all which cannot be demoted. This makes
the list scanning more efficient and solves some issues seen
with large numbers of inodes.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Rusty Russell [Thu, 30 Jul 2009 22:03:45 +0000 (16:03 -0600)]
lguest: update commentry
Every so often, after code shuffles, I need to go through and unbitrot
the Lguest Journey (see drivers/lguest/README). Since we now use RCU in
a simple form in one place I took the opportunity to expand that explanation.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Ingo Molnar <mingo@redhat.com> Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Rusty Russell [Thu, 30 Jul 2009 22:03:45 +0000 (16:03 -0600)]
lguest: fix comment style
I don't really notice it (except to begrudge the extra vertical
space), but Ingo does. And he pointed out that one excuse of lguest
is as a teaching tool, it should set a good example.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Ingo Molnar <mingo@redhat.com>
This refactors find_vqs, making it more readable and robust, and fixing
two regressions from 2.6.30:
- double free_irq causing BUG_ON on device removal
- probe failure when vq can't be assigned to msi-x vector
(reported on old host kernels)
Tested-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This makes delete vq the reverse of find vq.
This is required to make it possible to retry find_vqs
after a failure, otherwise the list gets corrupted.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Rusty Russell [Thu, 30 Jul 2009 22:03:43 +0000 (16:03 -0600)]
lguest: fix descriptor corruption in example launcher
1d589bb16b825b3a7b4edd34d997f1f1f953033d "Add serial number support
for virtio_blk, V4a" extended 'struct virtio_blk_config' to 536 bytes.
Lguest and S/390 both use an 8 bit value for the feature length, and
this change broke them (if the code is naive).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: John Cooper <john.cooper@redhat.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com>
powerpc/86xx: Update defconfig for GE Fanuc's PPC9A
General update of defconfig including the following notable changes:
- Enable GPIO access via sysfs on GE Fanuc's PPC9A.
- Enable Highmem support.
- Support for PCMCIA based daughter card.
Signed-off-by: Martyn Welch <martyn.welch@gefanuc.com> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Anton Vorontsov [Wed, 1 Jul 2009 17:39:25 +0000 (21:39 +0400)]
powerpc/85xx: Don't scan for TBI PHY addresses on MPC8569E-MDS boards
Sometimes (e.g. when there are no UEMs attached to a board)
fsl_pq_mdio_find_free() fails to find a spare address for a TBI PHY,
this is because get_phy_id() returns bogus 0x0000ffff values
(0xffffffff is expected), and therefore mdio bus probing fails with
the following message:
fsl-pq_mdio: probe of e0082120.mdio failed with error -16
And obviously ethernet doesn't work after this.
This patch solves the problem by adding tbi-phy node into mdio node,
so that we won't scan for spare addresses, we'll just use a fixed one.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Anton Vorontsov [Wed, 24 Jun 2009 16:30:28 +0000 (20:30 +0400)]
powerpc/85xx: Fix ethernet link detection on MPC8569E-MDS boards
Linux isn't able to detect link changes on ethernet ports that were
used by U-Boot. This is because U-Boot wrongly clears interrupt
polarity bit (INTPOL, 0x400) in the extended status register (EXT_SR,
0x1b) of Marvell PHYs.
There is no easy way for PHY drivers to know IRQ line polarity (we
could extract it from the device tree and pass it to phydevs, but
that'll be quite a lot of work), so for now just reset the PHYs to
their default states.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Kumar Gala [Thu, 30 Jul 2009 04:04:25 +0000 (23:04 -0500)]
powerpc/mm: Fix SMP issue with MMU context handling code
In switch_mmu_context() if we call steal_context_smp() to get a context
to use we shouldn't fall through and than call steal_context_up(). Doing
so can be problematic in that the 'mm' that steal_context_up() ends up
using will not get marked dirty in the stale_map[] for other CPUs that
might have used that mm. Thus we could end up with stale TLB entries in
the other CPUs that can cause all kinda of havoc.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Merge branch 'i2c-fixes-rc4' of git://aeryn.fluff.org.uk/bjdooks/linux
* 'i2c-fixes-rc4' of git://aeryn.fluff.org.uk/bjdooks/linux:
i2c-omap: OMAP3430 Silicon Errata 1.153
i2c-omap: In case of a NACK|ARDY|AL return from the ISR
i2c-omap: Bug in reading the RXSTAT/TXSTAT values from the I2C_BUFFSTAT register
i2c-sh_mobile: change module_init() to subsys_initcall()
i2c: strncpy does not null terminate string
i2c-s3c2410: s3c24xx_i2c_init: don't clobber IICLC value
Mainly to ease the copy-n-pasting of maitnainer addresses into email clients.
The script to perform this operation:
#! /bin/sh
#
# Change MAINTAINERS from
# P: name
# M: address
# to:
# M: name <address>
#
# Integrate P: and M: lines
#
perl -i -e 'local $/; while(<>) { s@P: ([^\n]+)\nM: ([^\n]+)\n@M: \1 <\2>\n@g; print; }' MAINTAINERS
#
# Quote names with periods, commas and parentheses
#
sed -r -i -e "s/^M: (.+)([\.,'\(])(.*) </M: \"\1\2\3\" </g" MAINTAINERS
Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Pavel Machek <pavel@ucw.cz> Acked-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Wed, 29 Jul 2009 22:04:28 +0000 (15:04 -0700)]
scripts/get_maintainer.pl: Add -f directory use
Don't require a specific file in a directory to be tested.
Also Arnd Bergmann pointed out that the MAINTAINERS pattern requirement
that directory patterns have a trailing slash was unnecessary and was
likely to be error prone. Removed that requirement.
Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
.../linux/uio.h:37: error: expected `=', `,', `;', `asm' or `__attribute__' before `iov_length'
.../linux/uio.h:47: error: expected declaration specifiers or `...' before `size_t'
move uio functions inside a __KERNEL__ block.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com> Acked-by: Sam Ravnborg <sam@ravnborg.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/serial/atmel_serial.c: fix compile when CONFIG_SERIAL_ATMEL=Y and CONFIG_SERIAL_ATMEL_CONSOLE=N
When SERIAL_ATMEL_CONSOLE is disabled, ATMEL_CONSOLE_DEVICE is set to
NULL, and trying to access ATMEL_CONSOLE_DEVICE->flags in
atmel_serial_probe makes the compile fail. This fixes the issue by only
accessing it if CONFIG_SERIAL_ATMEL_CONSOLE is defined
Signed-off-by: Albin Tonnerre <albin.tonnerre@free-electrons.com> Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Cc: Nicolas Ferre <nicolas.ferre@atmel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dave Hansen [Wed, 29 Jul 2009 22:04:18 +0000 (15:04 -0700)]
lib: flexible array implementation
Once a structure goes over PAGE_SIZE*2, we see occasional allocation
failures. Some people have chosen to switch over to things like vmalloc()
that will let them keep array-like access to such a large structures.
But, vmalloc() has plenty of downsides.
Here's an alternative. I think it's what Andrew was suggesting here:
http://lkml.org/lkml/2009/7/2/518
I call it a flexible array. It does all of its work in PAGE_SIZE bits, so
never does an order>0 allocation. The base level has
PAGE_SIZE-2*sizeof(int) bytes of storage for pointers to the second level.
So, with a 32-bit arch, you get about 4MB (4183112 bytes) of total
storage when the objects pack nicely into a page. It is half that on
64-bit because the pointers are twice the size. There's a table detailing
this in the code.
There are kerneldocs for the functions, but here's an
overview:
flex_array_alloc() - dynamically allocate a base structure
flex_array_free() - free the array and all of the
second-level pages
flex_array_free_parts() - free the second-level pages, but
not the base (for static bases)
flex_array_put() - copy into the array at the given index
flex_array_get() - copy out of the array at the given index
flex_array_prealloc() - preallocate the second-level pages
between the given indexes to
guarantee no allocs will occur at
put() time.
We could also potentially just pass the "element_size" into each of the
API functions instead of storing it internally. That would get us one
more base pointer on 32-bit.
I've been testing this by running it in userspace. The header and patch
that I've been using are here, as well as the little script I'm using to
generate the size table which goes in the kerneldocs.
http://sr71.net/~dave/linux/flexarray/
[akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com> Reviewed-by: 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>
Anton Vorontsov [Wed, 29 Jul 2009 22:04:16 +0000 (15:04 -0700)]
sdhci: get rid of "frequency too high" flood when using eSDHC
Since commit 8dfd0374be84793360db7fff2e635d2cd3bbcb21 ("MMC core: limit
minimum initialization frequency to 400kHz") MMC core checks for minimum
frequency, and that causes following messages flood when using eSDHC
controllers:
...
mmc0: Minimum clock frequency too high for identification mode
mmc0: Minimum clock frequency too high for identification mode
...
The warnings are legitimate, since if we'd use 133 MHz clocks for standard
SDHCI controllers, we'd not able to scale frequency down to 400 kHz.
But eSDHC controllers have a non-standard SD clock management, so we can
divide clock by 256 * 16, not just 256.
This patch introduces get_min_clock() callback for sdhci core and
implements it for sdhci-of driver, and thus fixes the issue.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com> Cc: Matt Fleming <matt@console-pimps.org> Cc: Ian Molton <ian@mnementh.co.uk> Cc: "Roberto A. Foglietta" <roberto.foglietta@gmail.com> Cc: Pierre Ossman <drzeus@drzeus.cx> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
commit d6580a9f15238b87e618310c862231ae3f352d2d ("kexec: sysrq: simplify
sysrq-c handler") changed the behavior of sysrq-c to unconditional
dereference of NULL pointer. So in cases with CONFIG_KEXEC, where
crash_kexec() was directly called from sysrq-c before, now it can be said
that a step of "real oops" was inserted before starting kdump.
However, in contrast to oops via SysRq-c from keyboard which results in
panic due to in_interrupt(), oops via "echo c > /proc/sysrq-trigger" will
not become panic unless panic_on_oops=1. It means that even if dump is
properly configured to be taken on panic, the sysrq-c from proc interface
might not start crashdump while the sysrq-c from keyboard can start
crashdump. This confuses traditional users of kdump, i.e. people who
expect sysrq-c to do common behavior in both of the keyboard and proc
interface.
This patch brings the keyboard and proc interface behavior of sysrq-c in
line, by forcing panic_on_oops=1 before oops in sysrq-c handler.
And some updates in documentation are included, to clarify that there is
no longer dependency with CONFIG_KEXEC, and that now the system can just
crash by sysrq-c if no dump mechanism is configured.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Cc: Brayan Arraes <brayan@yack.com.br> Cc: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This file makes use of various macros defined in files like asm/current.h
or asm-generic/resource.h. All these files can be included via sched.h.
The building of the !MMU ARM kernel (with additional patches) fails
without this change.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
net-dccp: suppress warning about large allocations from DCCP
The DCCP protocol tries to allocate some large hash tables during
initialisation using the largest size possible. This can be larger than
what the page allocator can provide so it prints a warning. However, the
caller is able to handle the situation so this patch suppresses the
warning.
Signed-off-by: Mel Gorman <mel@csn.ul.ie> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
profile: suppress warning about large allocations when profile=1 is specified
When profile= is used, a large buffer is allocated early at boot. This
can be larger than what the page allocator can provide so it prints a
warning. However, the caller is able to handle the situation so this
patch suppresses the warning.
Signed-off-by: Mel Gorman <mel@csn.ul.ie> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
page-allocator: allow too high-order warning messages to be suppressed with __GFP_NOWARN
The page allocator warns once when an order >= MAX_ORDER is specified.
This is to catch callers of the allocator that are always falling back to
their worst-case when it was not expected. However, there are cases where
the caller is behaving correctly but cannot suppress the warning. This
patch allows the warning to be suppressed by the callers by specifying
__GFP_NOWARN.
Signed-off-by: Mel Gorman <mel@csn.ul.ie> Acked-by: David Rientjes <rientjes@google.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After commit ec64f51545fffbc4cb968f0cea56341a4b07e85a ("cgroup: fix
frequent -EBUSY at rmdir"), cgroup's rmdir (especially against memcg)
doesn't return -EBUSY by temporary ref counts. That commit expects all
refs after pre_destroy() is temporary but...it wasn't. Then, rmdir can
wait permanently. This patch tries to fix that and change followings.
- set CGRP_WAIT_ON_RMDIR flag before pre_destroy().
- clear CGRP_WAIT_ON_RMDIR flag when the subsys finds racy case.
if there are sleeping ones, wakes them up.
- rmdir() sleeps only when CGRP_WAIT_ON_RMDIR flag is set.
eeprom/at25: bugfix "not ready" timeout after write
Under certain circumstances msleep(1) within the loop, which waits for the
EEPROM to be finished, might take longer than the timeout. On the next
loop the status register might now return to be ready and therefore the
loop finishes. The following check now tests if a timeout occurred and if
so returns an error although the device reported it was ready.
This fix replaces testing the occurrence of the timeout by testing the
"not ready" bit in the status register.
Signed-off-by: Sebastian Heutling <heutling@who-ing.de> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We cache a pid array for all threads that are opening the same "tasks"
file, but the pids in the array are always from the namespace of the
last process that opened the file, so all other threads will read pids
from that namespace instead of their own namespaces.
To fix it, we maintain a list of pid arrays, which is keyed by pid_ns.
The list will be of length 1 at most time.
Reported-by: Paul Menage <menage@google.com> Idea-by: Paul Menage <menage@google.com> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Reviewed-by: Serge Hallyn <serue@us.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
projects / mv-sheeva.git / log