Add a function to allow a requeueable work item to sleep till the thread
processing it is needed by the slow-work facility to perform other work.
Sometimes a work item can't progress immediately, but must wait for the
completion of another work item that's currently being processed by another
slow-work thread.
In some circumstances, the waiting item could instead - theoretically - put
itself back on the queue and yield its thread back to the slow-work facility,
thus waiting till it gets processing time again before attempting to progress.
This would allow other work items processing time on that thread.
However, this only works if there is something on the queue for it to queue
behind - otherwise it will just get a thread again immediately, and will end
up cycling between the queue and the thread, eating up valuable CPU time.
So, slow_work_sleep_till_thread_needed() is provided such that an item can put
itself on a wait queue that will wake it up when the event it is actually
interested in occurs, then call this function in lieu of calling schedule().
This function will then sleep until either the item's event occurs or another
work item appears on the queue. If another work item is queued, but the
item's event hasn't occurred, then the work item should requeue itself and
yield the thread back to the slow-work facility by returning.
This can be used by CacheFiles for an object that is being created on one
thread to wait for an object being deleted on another thread where there is
nothing on the queue for the creation to go and wait behind. As soon as an
item appears on the queue that could be given thread time instead, CacheFiles
can stick the creating object back on the queue and return to the slow-work
facility - assuming the object deletion didn't also complete.
Signed-off-by: David Howells <dhowells@redhat.com>
Add a function (slow_work_is_queued()) to permit the owner of a work item to
determine if the item is queued or not.
The work item is counted as being queued if it is actually on the queue, not
just if it is pending. If it is executing and pending, then it is not on the
queue, but will rather be put back on the queue when execution finishes.
This permits a caller to quickly work out if it may be able to put another,
dependent work item on the queue behind it, or whether it will have to wait
till that is finished.
This can be used by CacheFiles to work out whether the creation a new object
can be immediately deferred when it has to wait for an old object to be
deleted, or whether a wait must take place. If a wait is necessary, then the
slow-work thread can otherwise get blocked, preventing the deletion from
taking place.
Signed-off-by: David Howells <dhowells@redhat.com>
This adds support for starting slow work with a delay, similar
to the functionality we have for workqueues.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Add support for cancellation of queued slow work and delayed slow work items.
The cancellation functions will wait for items that are pending or undergoing
execution to be discarded by the slow work facility.
Attempting to enqueue work that is in the process of being cancelled will
result in ECANCELED.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Make the ability for the slow-work facility to take references on a work item
optional as not everyone requires this.
Even the internal slow-work stubs them out, so those can be got rid of too.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Wait for outstanding slow work items belonging to a module to clear when
unregistering that module as a user of the facility. This prevents the put_ref
code of a work item from being taken away before it returns.
Signed-off-by: David Howells <dhowells@redhat.com>
The mute-LED isn't synchronized with the actual mute state on some
HP laptops with IDT 92HD83xxx codecs. A similar hack using
check_power_status callback is added for this codec, too.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Now that the sysctl structures no longer have a ctl_name field
there is no reason to retain the definitions for CTL_NONE and
CTL_UNNUMBERED, or to explain their historic usage.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
* 'hostprogs-wmissing-prototypes' of git://git.kernel.org/pub/scm/linux/kernel/git/josh/linux-misc:
Makefile: Add -Wmising-prototypes to HOSTCFLAGS
oss: Mark loadhex static in hex2hex.c
dtc: Mark various internal functions static
dtc: Set "noinput" in the lexer to avoid an unused function
drm: radeon: Mark several functions static in mkregtable
arch/sparc/boot/*.c: Mark various internal functions static
arch/powerpc/boot/addRamDisk.c: Mark several internal functions static
arch/alpha/boot/tools/objstrip.c: Mark "usage" static
Documentation/vm/page-types.c: Declare checked_open static
genksyms: Mark is_reserved_word static
kconfig: Mark various internal functions static
kconfig: Make zconf.y work with current bison
Taken from socketcan-svn, fixed remaining todos, cleaned up, tested with a
phyCORE-MPC5200B-IO and a custom board.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Wolfgang Grandegger <wg@grandegger.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for setting a global default for whether or not a visible
cursor should be enabled when creating VCs. The default will be to do so,
unless overridden by the user at boot time or by a driver.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
LKML-Reference: <1258143251-5818-1-git-send-email-mjg@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
i2c: Add an interface to lock/unlock an I2C bus segment
i2c-piix4: Modify code name SB900 to Hudson-2
When the system has too many timers or too many aggregate
queued signals, the EAGAIN error is returned to application
from kernel, including timer_create() [POSIX.1b].
It means that the app exceeded the limit of pending signals,
but in general application writers do not expect this
outcome and the current silent failure can cause rare app
failures under very high load.
This patch adds a new message when we reach the limit
and if print_fatal_signals is enabled:
task/1234: reached RLIMIT_SIGPENDING, dropping signal
If you see this message and your system behaved unexpectedly,
you can run following command to lift the limit:
# ulimit -i unlimited
With help from Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>.
Signed-off-by: Naohiro Ooiwa <nooiwa@miraclelinux.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: oleg@redhat.com
LKML-Reference: <4AF6E7E2.9080406@miraclelinux.com>
[ Modified a few small details, gave surrounding code some love. ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If some of the flags are documented there, they all should be.
Signed-off-by: Nick Bowler <nbowler@elliptictech.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
That URL is out of date. Update it.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Matt LaPlante <kernel1@cyberdogtech.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: WANG Cong <amwang@redhat.com>
Acked-by: Matt LaPlante <kernel@cyberdogtech.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
As all in-tree drivers have been converted to not use cs_error() any more,
drop these functions and definitions, and update the Documentation.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
As a replacement to pcmcia_get_{first,next}_tuple() and
pcmcia_get_tuple_data(), three new -- and easier to use --
functions are added:
- pcmcia_get_tuple() to get the very first CIS entry of one
type.
- pcmcia_loop_tuple() to loop over all CIS entries of one type.
- pcmcia_get_mac_from_cis() to read out the hardware MAC address
from CISTPL_FUNCE.
Only a handful of drivers need these functions anyway, as most
CIS access is already handled by pcmcia_loop_config(), which
now shares the same backed (pccard_loop_tuple()) with
pcmcia_loop_tuple().
A pcmcia_get_mac_from_cis() bug noted by Komuro
<komurojun-mbn@nifty.com> has been fixed in this revision.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Frans Pop <elendil@planet.nl>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
The document currently uses large indentations which make the text
too wide for easy readability. Also improve general consistency.
Signed-off-by: Frans Pop <elendil@planet.nl>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
To unify control names, rename "PC Speaker" to "Speaker" for PPC ALSA drivers.
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
To avoid confusion in control names for the standard analog PC Beep generator
using a small Internal PC Speaker, rename all related "PC Speaker" and "PC
Beep" controls to "Beep" only. This name is more universal and can be also
used on more platforms without confusion.
Introduce also "Internal Speaker" in ControlNames.txt for systems with
full-featured build-in internal speaker.
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Rename Kprobes-based event tracer to kprobes-based tracing event
(kprobe-event), since it is not a tracer but an extensible
tracing event interface.
This also changes CONFIG_KPROBE_TRACER to CONFIG_KPROBE_EVENT
and sets it y by default.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
LKML-Reference: <20091104001247.3454.14131.stgit@harusame>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra suggested that we remove USER_SCHED at:
http://lkml.org/lkml/2009/3/21/67
Removing USER_SCHED removes a lot of code from the scheduler
and simplifies the code.
We already have the ability to do user based classification
which is tightened using PAM in userspace.
Schedule USER_SCHED for removal in 2.6.34
Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
LKML-Reference: <20091103214544.GI5495@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Conflicts:
tools/perf/Makefile
Merge reason: Resolve the conflict, merge to upstream and merge in
perf fixes so we can add a dependent patch.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This reverts commit d0646f7b636d067d715fab52a2ba9c6f0f46b0d7, as
requested by Eric Sandeen.
It can basically cause an ext4 filesystem to miss recovery (and thus get
mounted with errors) if the journal checksum does not match.
Quoth Eric:
"My hand-wavy hunch about what is happening is that we're finding a
bad checksum on the last partially-written transaction, which is
not surprising, but if we have a wrapped log and we're doing the
initial scan for head/tail, and we abort scanning on that bad
checksum, then we are essentially running an unrecovered filesystem.
But that's hand-wavy and I need to go look at the code.
We lived without journal checksums on by default until now, and at
this point they're doing more harm than good, so we should revert
the default-changing commit until we can fix it and do some good
power-fail testing with the fixes in place."
See
http://bugzilla.kernel.org/show_bug.cgi?id=14354
for all the gory details.
Requested-by: Eric Sandeen <sandeen@redhat.com>
Cc: Theodore Tso <tytso@mit.edu>
Cc: Alexey Fisher <bug-track@fisher-privat.net>
Cc: Maxim Levitsky <maximlevitsky@gmail.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Mathias Burén <mathias.buren@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
ALSA: hda - Don't check invalid HP pin
ALSA: dummy - Fix descriptions of pcm_substreams parameter
ALSA: pcmcia: use dynamic debug infrastructure, deprecate CS_CHECK (sound)
ALSA: hda: Use quirk mask for Dell Inspiron Mini9/Vostro A90 using ALC268
sound: via82xx: deactivate DXS controls of inactive streams
ALSA: snd-usb-caiaq: Bump version number to 1.3.20
ALSA: snd-usb-caiaq: Lock on stream start/unpause
ALSA: snd-usb-caiaq: Missing lock around use of buffer positions
ALSA: sound/parisc: Move dereference after NULL test
ALSA: sound: Move dereference after NULL test and drop unnecessary NULL tests
ALSA: hda_intel: Add the Linux device ID for NVIDIA HDA controller
ALSA: pcsp - Fix nforce workaround
ALSA: SND_CS5535AUDIO: Remove the X86 platform dependency
ASoC: Amstrad Delta: add info about the line discipline requirement to Kconfig help text
ASoC: Fix possible codec_dai->ops NULL pointer problems
ALSA: hda - Fix capture source checks for ALC662/663 codecs
ASoC: Serialize access to dapm_power_widgets()
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
tracing: Remove cpu arg from the rb_time_stamp() function
tracing: Fix comment typo and documentation example
tracing: Fix trace_seq_printf() return value
tracing: Update *ppos instead of filp->f_pos
Currently, if the high-res timers are unavailable, snd-pcsp does not
initialize. People who choose it over pcspkr, loose their console beeps
in that case and get annoyed.
With this patch, the console beeps remain regardless of the high-res
timers. Additionally, the "nopcm" modparam is added to forcibly
disable the PCM capabilities of the driver.
Signed-off-by: Stas Sergeev <stsp@aknet.ru>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Describe NUMA node symlink created for CPUs when CONFIG_NUMA is set.
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add brief descriptions for the following sysfs files:
/sys/devices/system/cpu/cpu#/topology/core_id
/sys/devices/system/cpu/cpu#/topology/core_siblings
/sys/devices/system/cpu/cpu#/topology/core_siblings_list
/sys/devices/system/cpu/cpu#/topology/physical_package_id
/sys/devices/system/cpu/cpu#/topology/thread_siblings
/sys/devices/system/cpu/cpu#/topology/thread_siblings_list
The descriptions in Documentation/cputopology.txt weren't very
informative, so I attempted a better description based on code
reading and hopeful guessing.
Updated Documentation/cputopology.txt with the better descriptions and
fixed some style issues.
Cc: Mike Travis <travis@sgi.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add brief descriptions for the following sysfs files:
/sys/devices/system/cpu/kernel_max
/sys/devices/system/cpu/offline
/sys/devices/system/cpu/online
/sys/devices/system/cpu/possible
/sys/devices/system/cpu/present
Excerpted the relevant information from Documentation/cputopology.txt
and pointed back to cputopology.txt as the authoritative source of
information.
Cc: Mike Travis <travis@sgi.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This interface has been around for a long time, but hasn't been
officially documented.
Document the top level sysfs directory for CPU attributes.
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Rename sysfs-devices-cache_disable to sysfs-devices-system-cpu, in
order to keep a stricter correlation between a sysfs directory and
its documentation.
Reported-by: David Rientjes <rientjes@google.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
