* pm-cpufreq:
cpufreq: don't leave stale policy pointer in cdbs->cur_policy
acpi-cpufreq: Add new sysfs attribute freqdomain_cpus
cpufreq: make sure frequency transitions are serialized
There's no reason we have to protect the blocked_hash and file_lock_list
with the same spinlock. With the tests I have, breaking it in two gives
a barely measurable performance benefit, but it seems reasonable to make
this locking as granular as possible.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Currently, the hashing that the locking code uses to add these values
to the blocked_hash is simply calculated using fl_owner field. That's
valid in most cases except for server-side lockd, which validates the
owner of a lock based on fl_owner and fl_pid.
In the case where you have a small number of NFS clients doing a lot
of locking between different processes, you could end up with all
the blocked requests sitting in a very small number of hash buckets.
Add a new lm_owner_key operation to the lock_manager_operations that
will generate an unsigned long to use as the key in the hashtable.
That function is only implemented for server-side lockd, and simply
XORs the fl_owner and fl_pid.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Having a global lock that protects all of this code is a clear
scalability problem. Instead of doing that, move most of the code to be
protected by the i_lock instead. The exceptions are the global lists
that the ->fl_link sits on, and the ->fl_block list.
->fl_link is what connects these structures to the
global lists, so we must ensure that we hold those locks when iterating
over or updating these lists.
Furthermore, sound deadlock detection requires that we hold the
blocked_list state steady while checking for loops. We also must ensure
that the search and update to the list are atomic.
For the checking and insertion side of the blocked_list, push the
acquisition of the global lock into __posix_lock_file and ensure that
checking and update of the blocked_list is done without dropping the
lock in between.
On the removal side, when waking up blocked lock waiters, take the
global lock before walking the blocked list and dequeue the waiters from
the global list prior to removal from the fl_block list.
With this, deadlock detection should be race free while we minimize
excessive file_lock_lock thrashing.
Finally, in order to avoid a lock inversion problem when handling
/proc/locks output we must ensure that manipulations of the fl_block
list are also protected by the file_lock_lock.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Instances either don't look at it at all (the majority of cases) or
only want it to find the superblock (which can be had as dentry->d_sb).
A few cases that want more are actually safe with dentry->d_inode -
the only precaution needed is the check that it hadn't been replaced with
NULL by rmdir() or by overwriting rename(), which case should be simply
treated as cache miss.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
iterate_dir(): new helper, replacing vfs_readdir().
struct dir_context: contains the readdir callback (and will get more stuff
in it), embedded into whatever data that callback wants to deal with;
eventually, we'll be passing it to ->readdir() replacement instead of
(data,filldir) pair.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Update the documentation with the driver's path changed in
commit 56fa1a6a6a
[media] s5p-fimc: Change the driver directory to exynos4-is
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Add compatible property for the Exynos5250 and enable the frame start
and frame end interrupts. These interrupts are needed for the Exynos5
FIMC-IS firmware. The driver enables those interrupt only where available,
depending on the 'compatible' property. This can be optimized further,
by exposing some API at the subdev driver, so the host driver can enable
extra interrupts only for the image processing chains involving FIMC-IS.
Signed-off-by: Shaik Ameer Basha <shaik.ameer@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This patch adds support for the Exynos5250 SoC variant of the FIMC-LITE
IP. A 'compatible' string is added for Exynos5250 compatible devices
and the capture DMA handling is reworked to use the FLITE_REG_CIFCNTSEQ
register, masking output DMA buffer address slots. The frame interrupt
is enabled so there are now 2 interrupts per frame. This likely can be
optimized in future by using any status registers that allow to figure
out what the last and the currently written frame buffer is. It would
also be more reliable in cases where there are high interrupt service
latencies.
Signed-off-by: Shaik Ameer Basha <shaik.ameer@samsung.com>
Signed-off-by: Arun Kumar K <arun.kk@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Konrad writes:
It has the 'feature-max-indirect-segments' implemented in both backend
and frontend. The current problem with the backend and frontend is that the
segment size is limited to 11 pages. It means we can at most squeeze in 44kB per
request. The ring can hold 32 (next power of two below 36) requests, meaning we
can do 1.4M of outstanding requests. Nowadays that is not enough.
The problem in the past was addressed in two ways - but neither one went upstream.
The first solution to this proposed by Justin from Spectralogic was to negotiate
the segment size. This means that the ‘struct blkif_sring_entry’ is now a variable size.
It can expand from 112 bytes (cover 11 pages of data - 44kB) to 1580 bytes
(256 pages of data - so 1MB). It is a simple extension by just making the array in the
request expand from 11 to a variable size negotiated. But it had limits: this extension
still limits the number of segments per request to 255 (as the total number must be
specified in the request, which only has an 8-bit field for that purpose).
The other solution (from Intel - Ronghui) was to create one extra ring that only has the
‘struct blkif_request_segment’ in them. The ‘struct blkif_request’ would be changed to have
an index in said ‘segment ring’. There is only one segment ring. This means that the size of
the initial ring is still the same. The requests would point to the segment and enumerate out
how many of the indexes it wants to use. The limit is of course the size of the segment.
If one assumes a one-page segment this means we can in one request cover ~4MB.
Those patches were posted as RFC and the author never followed up on the ideas on changing
it to be a bit more flexible.
There is yet another mechanism that could be employed (which these patches implement) - and it
borrows from VirtIO protocol. And that is the ‘indirect descriptors’. This very similar to
what Intel suggests, but with a twist. The twist is to negotiate how many of these
'segment' pages (aka indirect descriptor pages) we want to support (in reality we negotiate
how many entries in the segment we want to cover, and we module the number if it is
bigger than the segment size).
This means that with the existing 36 slots in the ring (single page) we can cover:
32 slots * each blkif_request_indirect covers: 512 * 4096 ~= 64M. Since we ample space
in the blkif_request_indirect to span more than one indirect page, that number (64M)
can be also multiplied by eight = 512MB.
Roger Pau Monne took the idea and implemented them in these patches. They work
great and the corner cases (migration between backends with and without this extension)
work nicely. The backend has a limit right now off how many indirect entries
it can handle: one indirect page, and at maximum 256 entries (out of 512 - so 50% of the page
is used). That comes out to 32 slots * 256 entries in a indirect page * 1 indirect page
per request * 4096 = 32MB.
This is a conservative number that can change in the future. Right now it strikes
a good balance between giving excellent performance, memory usage in the backend, and
balancing the needs of many guests.
In the patchset there is also the split of the blkback structure to be per-VBD.
This means that the spinlock contention we had with many guests trying to do I/O and
all the blkback threads hitting the same lock has been eliminated.
Also there are bug-fixes to deal with oddly sized sectors, insane amounts on
th ring, and also a security fix (posted earlier).
This patch adds new combatible strings for hdmi, mixer, ddc
and hdmiphy. It follows the convention of using compatible string
which represent the SoC in which the IP was added for the first
time.
Drivers continue to support the previous compatible strings
but further addition of these compatible strings in device tree
is deprecated.
Signed-off-by: Rahul Sharma <rahul.sharma@samsung.com>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
ASoC: More updates for v3.11
Some more fixes and enhancements, and also a bunch of refectoring for
AC'97 support which enables more than one AC'97 controller driver to be
built in.
Several drivers need font support independent of CONFIG_VT, cfr. commit
9cbce8d7e1dae0744ca4f68d62aa7de18196b6f4, "console/font: Refactor font
support code selection logic").
Hence move the fonts and their support logic from drivers/video/console/ to
its own library directory lib/fonts/.
This also allows to limit processing of drivers/video/console/Makefile to
CONFIG_VT=y again.
[Kevin Hilman <khilman@linaro.org>: Update arch/arm/boot/compressed/Makefile]
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
The i915 driver has been fixed not to modify the mode argument of the
encoder mode_fixup operation. Remove the related comment from the
documentation.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This adds support for a generic reservations framework that can be
hooked up to ttm and dma-buf and allows easy sharing of reservations
across devices.
The idea is that a dma-buf and ttm object both will get a pointer
to a struct reservation_object, which has to be reserved before
anything is done with the contents of the dma-buf.
Changes since v1:
- Fix locking issue in ticket_reserve, which could cause mutex_unlock
to be called too many times.
Changes since v2:
- All fence related calls and members have been taken out for now,
what's left is the bare minimum to be useful for ttm locking conversion.
Changes since v3:
- Removed helper functions too. The documentation has an example
implementation for locking. With the move to ww_mutex there is no
need to have much logic any more.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Adding support for max-pixelclock and max-width device tree
entries. As some devices that use the tilcdc hardware module
have restrictions on the allowed/tested values. Also update DT
bindings document to reflect new parameters.
Signed-off-by: Darren Etheridge <detheridge@ti.com>
Acked-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Commits fcf8058 (cpufreq: Simplify cpufreq_add_dev()) and aa77a52
(cpufreq: acpi-cpufreq: Don't set policy->related_cpus from .init())
changed the contents of the "related_cpus" sysfs attribute on systems
where acpi-cpufreq is used and user space can't get the list of CPUs
which are in the same hardware coordination CPU domain (provided by
the ACPI AML method _PSD) via "related_cpus" any more.
To make up for that loss add a new sysfs attribute "freqdomian_cpus"
for the acpi-cpufreq driver which exposes the list of CPUs in the
same domain regardless of whether it is coordinated by hardware or
software.
[rjw: Changelog, documentation]
References: https://bugzilla.kernel.org/show_bug.cgi?id=58761
Reported-by: Jean-Philippe Halimi <jean-philippe.halimi@exascale-computing.eu>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
GMT G762/763 fan speed PWM controller is connected directly to a fan
and performs closed-loop or open-loop control of the fan speed. Two
modes - PWM or DC - are supported by the chip. Introduced driver
provides various knobs to control the operations of the chip (via
sysfs interface). Specific characteristics of the system can be passed
either using board init code or via DT. Documentation for both the
driver and DT bindings are also provided.
Signed-off-by: Arnaud Ebalard <arno@natisbad.org>
Tested-by: Simon Guinot <simon.guinot@sequanux.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Adding another way that is device tree to pass the shunt resistor
value to driver except for platform data.
Signed-off-by: Tang Yuantian <Yuantian.Tang@freescale.com>
[Guenter Roeck: Added missing of.h include]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Replace some written information with tables to improve readability
and to simplify adding newer devices in the future.
Signed-off-by: Robert Coulson <rob.coulson@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
These changes add DS1731 chip support to the ds1621 driver,
Kconfig, and documentation.
Signed-off-by: Robert Coulson <rob.coulson@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Due to a lack of device and vendor identification registers, the
Dallas/Maxim DS16xx devices cannot be uniquely detected, sometimes
resulting in false positives. Therefore, the detect function is
being removed in favor of explicit device instantiation.
Signed-off-by: Robert Coulson <rob.coulson@gmail.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Add definitions, information, and code for ds1631 chip support
to the ds1621 driver.
Signed-off-by: Robert Coulson <rob.coulson@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The ds1721 device can be configured for 9..12 bit resolutions;
add a sysfs attribute for userspace to configure this attribute.
The definition, description, details, and usage are shown in the
documentation and were crafted from an LM73 driver patch done by
Chris Verges & Guenter Roeck).
Signed-off-by: Robert Coulson <rob.coulson@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Update the ds1621 documentation, driver, and Kconfig with
ds1721 chip support.
Signed-off-by: Robert Coulson <rob.coulson@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The DT-binding for MMC_CAP2_FULL_PWR_CYCLE, is used to indicate whether
it is possible to perform a full power cycle of the card.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
As of now we rely on code outside of the driver to set the ciu clock
frequency. There's no reason to do that. Add support for setting up
the clock in the driver during probe.
Signed-off-by: Doug Anderson <dianders@chromium.org>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
It is possible to specify a regulator that should be turned on when
dw_mmc is probed. At the moment dw_mmc will fail to use the regulator
properly if the regulator probes after dw_mmc. Fix this problem by
honoring EPROBE_DEFER.
At the same time move the regulator code out of the slot init code.
We only specify one regulator for the whole device and other parts of
the code (like suspend/resume) assume that the regulator has only been
enabled once.
Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
Instead of using a GPIO to turn on/off the CAN transceiver, it is better to
use a regulator as some systems may use a PMIC to power the CAN transceiver.
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
