This is in preparation for the full dynticks feature. While
remotely reading the cputime of a task running in a full
dynticks CPU, we'll need to do some extra-computation. This
way we can account the time it spent tickless in userspace
since its last cputime snapshot.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Allow to dynamically switch between tick and virtual based
cputime accounting. This way we can provide a kind of "on-demand"
virtual based cputime accounting. In this mode, the kernel relies
on the context tracking subsystem to dynamically probe on kernel
boundaries.
This is in preparation for being able to stop the timer tick in
more places than just the idle state. Doing so will depend on
CONFIG_VIRT_CPU_ACCOUNTING_GEN which makes it possible to account
the cputime without the tick by hooking on kernel/user boundaries.
Depending whether the tick is stopped or not, we can switch between
tick and vtime based accounting anytime in order to minimize the
overhead associated to user hooks.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
If we want to stop the tick further idle, we need to be
able to account the cputime without using the tick.
Virtual based cputime accounting solves that problem by
hooking into kernel/user boundaries.
However implementing CONFIG_VIRT_CPU_ACCOUNTING require
low level hooks and involves more overhead. But we already
have a generic context tracking subsystem that is required
for RCU needs by archs which plan to shut down the tick
outside idle.
This patch implements a generic virtual based cputime
accounting that relies on these generic kernel/user hooks.
There are some upsides of doing this:
- This requires no arch code to implement CONFIG_VIRT_CPU_ACCOUNTING
if context tracking is already built (already necessary for RCU in full
tickless mode).
- We can rely on the generic context tracking subsystem to dynamically
(de)activate the hooks, so that we can switch anytime between virtual
and tick based accounting. This way we don't have the overhead
of the virtual accounting when the tick is running periodically.
And one downside:
- There is probably more overhead than a native virtual based cputime
accounting. But this relies on hooks that are already set anyway.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
If the architecture doesn't provide an implementation of
nsecs_to_cputime(), the cputime accounting core uses a
default one that converts the nanoseconds to jiffies. However
this only makes sense if we use the jiffies based cputime.
For now it doesn't matter much because this API is only
called on code that uses jiffies based cputime accounting.
But the code may evolve and this API may be used more
broadly in the future. Keeping this default implementation
around is very error prone as it may introduce a bug and
hide it on architectures that don't override this API.
Fix this by moving this definition to the jiffies based
cputime headers as it is the only place where it belongs to.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
The full dynticks cputime accounting that we'll soon introduce
will rely on sched_clock(). And its clock can have a per
nanosecond granularity.
To prepare for this, we need to have a cputime_t implementation
that has this precision.
ia64 virtual cputime accounting already uses that granularity
so all we need is to librarize its implementation in the asm
generic headers.
Also librarize the default per jiffy granularity cputime_t
as well so that we can easily pick either implementation
depending on the cputime accounting config we choose.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Export the context state: whether we run in user / kernel
from the context tracking subsystem point of view.
This is going to be used by the generic virtual cputime
accounting subsystem that is needed to implement the full
dynticks.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Pull more s390 patches from Martin Schwidefsky:
"A couple of bug fixes: one of the transparent huge page primitives is
broken, the sched_clock function overflows after 417 days, the XFS
module has grown too large for -fpic and the new pci code has broken
normal channel subsystem notifications."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/chsc: fix SEI usage
s390/time: fix sched_clock() overflow
s390: use -fPIC for module compile
s390/mm: fix pmd_pfn() for thp
- fix(es) for compound buffers
- fix for dquot soft timer asserts due to overflow of d_blk_softlimit
- fix for regression in dir v2 code introduced in commit 20f7e9f3
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Merge tag 'for-linus-v3.8-rc4' of git://oss.sgi.com/xfs/xfs
Pull xfs bugfixes from Ben Myers:
- fix(es) for compound buffers
- fix for dquot soft timer asserts due to overflow of d_blk_softlimit
- fix for regression in dir v2 code introduced in commit 20f7e9f372
("xfs: factor dir2 block read operations")
* tag 'for-linus-v3.8-rc4' of git://oss.sgi.com/xfs/xfs:
xfs: recalculate leaf entry pointer after compacting a dir2 block
xfs: remove int casts from debug dquot soft limit timer asserts
xfs: fix the multi-segment log buffer format
xfs: fix segment in xfs_buf_item_format_segment
xfs: rename bli_format to avoid confusion with bli_formats
xfs: use b_maps[] for discontiguous buffers
* cpuidle initialization regression fix from Krzysztof Mazur.
* cpuidle fix for power usage fields handling from Daniel Lezcano.
* ACPI build fix from Yinghai Lu.
-
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Merge tag 'pm+acpi-for-3.8-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI and power management fixes from Rafael Wysocki:
- cpuidle regression fix related to the initialization of state
kobjects from Krzysztof Mazur.
- cpuidle fix removing some not very useful code and making some
user-visible problems go away at the same time. From Daniel Lezcano.
- ACPI build fix from Yinghai Lu.
* tag 'pm+acpi-for-3.8-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
cpuidle: remove the power_specified field in the driver
ACPI / glue: Fix build with ACPI_GLUE_DEBUG set
cpuidle: fix number of initialized/destroyed states
Dave Jones hit this assert when doing a compile on recent git, with
CONFIG_XFS_DEBUG enabled:
XFS: Assertion failed: (char *)dup - (char *)hdr == be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup)), file: fs/xfs/xfs_dir2_data.c, line: 828
Upon further digging, the tag found by xfs_dir2_data_unused_tag_p(dup)
contained "2" and not the proper offset, and I found that this value was
changed after the memmoves under "Use a stale leaf for our new entry."
in xfs_dir2_block_addname(), i.e.
memmove(&blp[mid + 1], &blp[mid],
(highstale - mid) * sizeof(*blp));
overwrote it.
What has happened is that the previous call to xfs_dir2_block_compact()
has rearranged things; it changes btp->count as well as the
blp array. So after we make that call, we must recalculate the
proper pointer to the leaf entries by making another call to
xfs_dir2_block_leaf_p().
Dave provided a metadump image which led to a simple reproducer
(create a particular filename in the affected directory) and this
resolves the testcase as well as the bug on his live system.
Thanks also to dchinner for looking at this one with me.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Tested-by: Dave Jones <davej@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
The int casts here make it easy to trigger an assert with a large
soft limit. For example, set a >4TB soft limit on an empty volume
to reproduce a (0 > -x) comparison due to an overflow of
d_blk_softlimit.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Per Dave Chinner suggestion, this patch:
1) Corrects the detection of whether a multi-segment buffer is
still tracking data.
2) Clears all the buffer log formats for a multi-segment buffer.
Signed-off-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Not every segment in a multi-segment buffer is dirty in a
transaction and they will not be outputted. The assert in
xfs_buf_item_format_segment() that checks for the at least
one chunk of data in the segment to be used is not necessary
true for multi-segmented buffers.
Signed-off-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Rename the bli_format structure to __bli_format to avoid
accidently confusing them with the bli_formats pointer.
Signed-off-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Commits starting at 77c1a08 introduced a multiple segment support
to xfs_buf. xfs_trans_buf_item_match() could not find a multi-segment
buffer in the transaction because it was looking at the single segment
block number rather than the multi-segment b_maps[0].bm.bn. This
results on a recursive buffer lock that can never be satisfied.
This patch:
1) Changed the remaining b_map accesses to be b_maps[0] accesses.
2) Renames the single segment b_map structure to __b_map to avoid
future confusion.
Signed-off-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
In commit 281dc5c5ec ("Give up on pushing CC_OPTIMIZE_FOR_SIZE") we
already changed the actual default value, but the help-text still
suggested 'y'. Fix the help text too, for all the same reasons.
Sadly, -Os keeps on generating some very suboptimal code for certain
cases, to the point where any I$ miss upside is swamped by the downside.
The main ones are:
- using "rep movsb" for memcpy, even on CPU's where that is
horrendously bad for performance.
- not honoring branch prediction information, so any I$ footprint you
win from smaller code, you lose from less code density in the I$.
- using divide instructions when that is very expensive.
Signed-off-by: Kirill Smelkov <kirr@mns.spb.ru>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the build error:
drivers/built-in.o: In function `twl_probe':
drivers/mfd/twl-core.c:1256: undefined reference to `devm_regmap_init_i2c'
make: *** [vmlinux] Error 1
Signed-off-by: liu chuansheng <chuansheng.liu@intel.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
[ Samuel is busy, taking it directly - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[ We should make fun of people who can't speel too, but then we'd have
no time for any real work at all - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 1b963c81b1 ("lockdep, rwsem: provide down_write_nest_lock()")
contains a bug in a codepath when CONFIG_DEBUG_LOCK_ALLOC is disabled,
which causes down_read() to be called instead of down_write() by mistake
on such configurations. Fix that.
Reported-and-tested-by: Andrew Clayton <andrew@digital-domain.net>
Reported-and-tested-by: Zlatko Calusic <zlatko.calusic@iskon.hr>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Yet a few more fixes popped up in this week.
The biggest change here is the addition of pinctrl support for Atmel,
which turned out to be almost mandatory to make things working.
The rest are a few fixes for M-Audio usb-audio device and a fix for
regression of HD-audio HDMI codecs with alsactl in the recent kernel.
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Merge tag 'sound-3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull second round of sound fixes from Takashi Iwai:
"Yet a few more fixes popped up in this week.
The biggest change here is the addition of pinctrl support for Atmel,
which turned out to be almost mandatory to make things working.
The rest are a few fixes for M-Audio usb-audio device and a fix for
regression of HD-audio HDMI codecs with alsactl in the recent kernel."
* tag 'sound-3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: hda/hdmi - Work around "alsactl restore" errors
ALSA: usb-audio: selector map for M-Audio FT C400
ALSA: usb-audio: M-Audio FT C400 skip packet quirk
ALSA: usb-audio: correct M-Audio C400 clock source quirk
ALSA: usb - fix race in creation of M-Audio Fast track pro driver
ASoC: atmel-ssc: add pinctrl selection to driver
ARM: at91/dts: add pinctrl support for SSC peripheral
Pull scsi target fixes from Nicholas Bellinger:
"This includes an important >= v3.6 regression bugfix for active I/O
shutdown (Roland), some TMR related failure / corner cases fixes for
long outstanding I/O (Roland), two FCoE target mode fabric fabric role
fixes (MDR), a fix for an incorrect sense code during LUN
communication failure (Dr. Hannes), plus a handful of other minor
fixes.
There are still some outstanding zero-length control CDB regression
fixes that need to be addressed for v3.8, that will be coming in a
follow-up PULL request."
* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
iscsi-target: Fix CmdSN comparison (use cmd->cmd_sn instead of cmd->stat_sn)
target: Release se_cmd when LUN lookup fails for TMR
target: Fix use-after-free in LUN RESET handling
target: Fix missing CMD_T_ACTIVE bit regression for pending WRITEs
tcm_fc: Do not report target role when target is not defined
tcm_fc: Do not indicate retry capability to initiators
target: Use TCM_NO_SENSE for initialisation
target: Introduce TCM_NO_SENSE
target: use correct sense code for LUN communication failure
Pull ext3 and udf fixes from Jan Kara:
"One ext3 performance regression fix and one udf regression fix (oops
on interrupted mount)."
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
UDF: Fix a null pointer dereference in udf_sb_free_partitions
jbd: don't wake kjournald unnecessarily
Pull x86 fixes from Peter Anvin:
"This is mainly a workaround for a bug in Sandy Bridge graphics which
causes corruption of certain memory pages."
* 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/Sandy Bridge: Sandy Bridge workaround depends on CONFIG_PCI
x86/Sandy Bridge: mark arrays in __init functions as __initconst
x86/Sandy Bridge: reserve pages when integrated graphics is present
x86, efi: correct precedence of operators in setup_efi_pci
Timur Tabi no longer works for Freescale, so update the email address
and status for all of his maintained projects.
Also mark the QE library as orphaned, for lack of interest in
maintaining it.
The CS4270 driver is marked as "Odd Fixes" because appropriate hardware
is no longer available.
Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the requested firmware file size is 0 bytes in the filesytem, we
will try to vmalloc(0), which causes a warning:
vmalloc: allocation failure: 0 bytes
kworker/1:1: page allocation failure: order:0, mode:0xd2
__vmalloc_node_range+0x164/0x208
__vmalloc_node+0x4c/0x58
vmalloc+0x38/0x44
_request_firmware_load+0x220/0x6b0
request_firmware+0x64/0xc8
wl18xx_setup+0xb4/0x570 [wl18xx]
wlcore_nvs_cb+0x64/0x9f8 [wlcore]
request_firmware_work_func+0x94/0x100
process_one_work+0x1d0/0x750
worker_thread+0x184/0x4ac
kthread+0xb4/0xc0
To fix this, check whether the file size is less than or equal to zero
in fw_read_file_contents().
Cc: stable <stable@vger.kernel.org> [3.7]
Signed-off-by: Luciano Coelho <coelho@ti.com>
Acked-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the default iosched is built as module, the kernel may deadlock
while trying to load the iosched module on device probe if the probing
was running off async. This is because async_synchronize_full() at
the end of module init ends up waiting for the async job which
initiated the module loading.
async A modprobe
1. finds a device
2. registers the block device
3. request_module(default iosched)
4. modprobe in userland
5. load and init module
6. async_synchronize_full()
Async A waits for modprobe to finish in request_module() and modprobe
waits for async A to finish in async_synchronize_full().
Because there's no easy to track dependency once control goes out to
userland, implementing properly nested flushing is difficult. For
now, make module init perform async_synchronize_full() iff module init
has queued async jobs as suggested by Linus.
This avoids the described deadlock because iosched module doesn't use
async and thus wouldn't invoke async_synchronize_full(). This is
hacky and incomplete. It will deadlock if async module loading nests;
however, this works around the known problem case and seems to be the
best of bad options.
For more details, please refer to the following thread.
http://thread.gmane.org/gmane.linux.kernel/1420814
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Alex Riesen <raa.lkml@gmail.com>
Tested-by: Ming Lei <ming.lei@canonical.com>
Tested-by: Alex Riesen <raa.lkml@gmail.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
cbc0dd1 "s390/pci: CHSC PCI support for error and availability events"
introduced a new SEI notification type as part of pci support.
The way SEI was called with nt2 and nt0 consecutive broke the nt0
stuff used for channel subsystem notifications.
The reason why this was broken with the mentioned patch is that you
cannot selectively disable type 0 notifications (so even when asked
for type 2 only, type 0 could be presented).
The way to do it is to tell SEI which types of notification you can
process and -this is the important part- look at the SEI result which
notification type you actually received.
Reviewed-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Tested-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Converting a 64 Bit TOD format value to nanoseconds means that the value
must be divided by 4.096. In order to achieve that we multiply with 125
and divide by 512.
When used within sched_clock() this triggers an overflow after appr.
417 days. Resulting in a sched_clock() return value that is much smaller
than previously and therefore may cause all sort of weird things in
subsystems that rely on a monotonic sched_clock() behaviour.
To fix this implement a tod_to_ns() helper function which converts TOD
values without overflow and call this function from both places that
open coded the conversion: sched_clock() and kvm_s390_handle_wait().
Cc: stable@kernel.org
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
FSI - DA7210 needs amixer settings to use it.
This patch adds quick setting guide
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
There have been a number of new syscalls introduced to arch/arm/ since
the compat layer was implemented for arm64, so add pointers to the
relevant functions to the compat syscall table.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
When "alsactl restore" is performed on HDMI codecs, it tries to
restore the channel map value since the channel map controls are
writable. But hdmi_chmap_ctl_put() returns -EBADFD when no PCM stream
is assigned yet, and this results in an error message from alsactl.
Although the error is harmless, it's certainly ugly and can be
regarded as a regression.
As a workaround, this patch changes the return code in such a case to
be zero for making others happy. (A slight excuse is: when the chmap
is changed through the proper alsa-lib API, the PCM status is checked
there anyway, so we don't have to be too strict in the kernel side.)
Cc: <stable@vger.kernel.org> [v3.7+]
Signed-off-by: Takashi Iwai <tiwai@suse.de>
We realized that the power usage field is never filled and when it
is filled for tegra, the power_specified flag is not set causing all
of these values to be reset when the driver is initialized with
set_power_state().
However, the power_specified flag can be simply removed under the
assumption that the states are always backward sorted, which is the
case with the current code.
This change allows the menu governor select function and the
cpuidle_play_dead() to be simplified. Moreover, the
set_power_states() function can removed as it does not make sense
any more.
Drop the power_specified flag from struct cpuidle_driver and make
the related changes as described above.
As a consequence, this also fixes the bug where on the dynamic
C-states system, the power fields are not initialized.
[rjw: Changelog]
References: https://bugzilla.kernel.org/show_bug.cgi?id=42870
References: https://bugzilla.kernel.org/show_bug.cgi?id=43349
References: https://lkml.org/lkml/2012/10/16/518
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Due to a series of problems with the handling of Atmel, a combination of
making changes that make other branches instantly buggy and a general
failure to deal with the resulting issues effectively, v3.8 Atmel audio
currently won't work at all for DT boards without adding pinctrl
definitions and a request for those.
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Merge tag 'asoc-atmel-pinctrl' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: atmel: Fixes for pinctrl
Due to a series of problems with the handling of Atmel, a combination of
making changes that make other branches instantly buggy and a general
failure to deal with the resulting issues effectively, v3.8 Atmel audio
currently won't work at all for DT boards without adding pinctrl
definitions and a request for those.
to tracing_on" caused two regressions.
1) The irqs off latency tracer no longer starts if tracing_on is off
when the tracer is set, and then tracing_on is enabled. The tracing_on
file needs the hook that tracing_enabled had to enable tracers if they
request it (call the tracer's start() method).
2) That commit had a separate change that really should have been a
separate patch, but it must have been added accidently with the -a
option of git commit. But as the change is still related to the commit
it wasn't noticed in review. That change, changed the way blocking is
done by the trace_pipe file with respect to the tracing_on settings.
I've been told that this change breaks current userspace, and this
specific change is being reverted.
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Merge tag 'trace-3.8-rc3-regression-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing regression fixes from Steven Rostedt:
"The clean up patch commit 0fb9656d95 "tracing: Make tracing_enabled
be equal to tracing_on" caused two regressions.
1) The irqs off latency tracer no longer starts if tracing_on is off
when the tracer is set, and then tracing_on is enabled. The
tracing_on file needs the hook that tracing_enabled had to enable
tracers if they request it (call the tracer's start() method).
2) That commit had a separate change that really should have been a
separate patch, but it must have been added accidently with the -a
option of git commit. But as the change is still related to the
commit it wasn't noticed in review. That change, changed the way
blocking is done by the trace_pipe file with respect to the
tracing_on settings. I've been told that this change breaks
current userspace, and this specific change is being reverted."
* tag 'trace-3.8-rc3-regression-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix regression of trace_pipe
tracing: Fix regression with irqsoff tracer and tracing_on file
The debugfs optimisations merged in v3.8 weren't my finest hour, there
were a number of cases that the more complex algorithm made worse
especially around the error handling. This patch series should address
those issues.
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Merge tag 'regmap-debugfs-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap
Pull regmap debugfs optimisation fixes from Mark Brown:
"The debugfs optimisations merged in v3.8 weren't my finest hour, there
were a number of cases that the more complex algorithm made worse
especially around the error handling. This patch series should
address those issues."
* tag 'regmap-debugfs-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
regmap: debugfs: Make sure we store the last entry in the offset cache
regmap: debugfs: Ensure a correct return value for empty caches
regmap: debugfs: Discard the cache if we fail to allocate an entry
regmap: debugfs: Fix check for block start in cached seeks
regmap: debugfs: Fix attempts to read nonexistant register blocks
A few fixes for the regulator subsystems, a few driver specific things
plus a fix for the interaction between regultor_can_change_voltage() and
continuous voltage ranges both of which were added for this release.
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Merge tag 'regulator-3.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator
Pull regulator fixes from Mark Brown:
"A few fixes for the regulator subsystems, a few driver specific things
plus a fix for the interaction between regultor_can_change_voltage()
and continuous voltage ranges both of which were added for this
release."
* tag 'regulator-3.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
regulator: max8998: Ensure enough delay time for max8998_set_voltage_buck_time_sel
regulator: max8998: Use uV in voltage_map_desc
regulator: max8997: Use uV in voltage_map_desc
regulator: core: Fix comment for regulator_register()
regulator: core: Fix continuous_voltage_range case in regulator_can_change_voltage
regulator: s5m8767: Fix probe failure due to stack corruption
This patch fixes a regression caused by commit bff943af6f "udf: Fix memory
leak when mounting" due to which it was triggering a kernel null point
dereference in case of interrupted mount OR when allocating memory to
sbi->s_partmaps failed in function udf_sb_alloc_partition_maps.
Reported-and-tested-by: James Hogan <james@albanarts.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Ashish Sangwan <a.sangwan@samsung.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Don't send an extra wakeup to kjournald in the case where we
already have the proper target in j_commit_request, i.e. that
commit has already been requested for commit.
commit d9b0193 "jbd: fix fsync() tid wraparound bug" changed
the logic leading to a wakeup, but it caused some extra wakeups
which were found to lead to a measurable performance regression.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2 fixes to prevent unconditional re-compile of dts files on arm and arm64.
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Merge tag 'dt-fixes-for-3.8' of git://sources.calxeda.com/kernel/linux
Pull devicetree fixes from Rob Herring:
"Two fixes to prevent unconditional re-compile of dts files on arm and
arm64."
* tag 'dt-fixes-for-3.8' of git://sources.calxeda.com/kernel/linux:
ARM: dts: prevent *.dtb from always being rebuilt
arm64: dts: prevent *.dtb from always being rebuilt
Andrew Morton pointed this out a month ago, and then I completely forgot
about it.
If we read a partial last page of a block device, we will zero out the
end of the page, but since that page can then be mapped into user space,
we should also make sure to flush the cache on architectures that have
virtual caches. We have the flush_dcache_page() function for this, so
use it.
Now, in practice this really never matters, because nobody sane uses
virtual caches to begin with, and they largely exist on old broken RISC
arhitectures.
And even if you did run on one of those obsolete CPU's, the whole "mmap
and access the last partial page of a block device" behavior probably
doesn't actually exist. The normal IO functions (read/write) will never
see the zeroed-out part of the page that migth not be coherent in the
cache, because they honor the size of the device.
So I'm marking this for stable (3.7 only), but I'm not sure anybody will
ever care.
Pointed-out-by: Andrew Morton <akpm@linux-foundation.org>
Cc: stable@vger.kernel.org # 3.7
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Most of commits found here are for ASoC device specific fixes,
arizona, cs4271, wm5102, wm2200, etc, in addition to a couple of
memory leak fixes in ASoC core.
Other than that, regression fixes in HD-audio and USB-audio, and
a fix for new Realtek codecs.
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Merge tag 'sound-3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"Most of commits found here are for ASoC device specific fixes,
arizona, cs4271, wm5102, wm2200, etc, in addition to a couple of
memory leak fixes in ASoC core.
Other than that, regression fixes in HD-audio and USB-audio, and a fix
for new Realtek codecs."
* tag 'sound-3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (30 commits)
ALSA: usb-audio: Fix NULL dereference by access to non-existing substream
ALSA: hda - Add support of new codec ALC284
ALSA: usb-audio: Make ebox44_table static
ALSA: hdspm - Fix wordclock status on AES32
Revert "ALSA: hda - Shut up pins at power-saving mode with Conexnat codecs"
ALSA: hda - Disable runtime D3 for Intel CPT & co
ALSA: pxa27x: fix ac97 warm reset
ALSA: pxa27x: fix ac97 cold reset
ASoC: wm_adsp: Ensure that block writes are from DMA aligned addresses
ASoC: wm2000: Fix sense of speech clarity enable
ASoC: wm5100: Remove DSP B and left justified formats
ASoC: arizona: Remove DSP B and left justified AIF modes
ASoC: wm2200: Remove DSP B and left justified AIF modes
ASoC: wm5102: Improve speaker enable performance
ASoC: core: fix the memory leak in case of remove_aux_dev()
ASoC: core: fix the memory leak in case of device_add() failure
ASoC: cs42l52: Catch no-match case in cs42l52_get_clk
ASoC: lm49453: Update lm49453_reg_defs values as per LM49453 HW revision-B
ASoC: lm49453: Fix adc, mic and sidetone volume ranges
ASoC: arizona: Correct FLL source definitions
...
Commit 0fb9656d "tracing: Make tracing_enabled be equal to tracing_on"
changes the behaviour of trace_pipe, ie. it makes trace_pipe return if
we've read something and tracing is enabled, and this means that we have
to 'cat trace_pipe' again and again while running tests.
IMO the right way is if tracing is enabled, we always block and wait for
ring buffer, or we may lose what we want since ring buffer's size is limited.
Link: http://lkml.kernel.org/r/1358132051-5410-1-git-send-email-bo.li.liu@oracle.com
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
