There are several fixes in this patch (mostly because it's hard
splitting them up):
- Revert the name field in struct hwrng back to 'const'. Also, don't
do an extra kmalloc for the name - just wasteful.
- Deal with allocation failures properly.
- Use IDA to allocate device number instead of brute forcing one.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
- ring init improvements (Chris)
- vebox2 support (Zhao Yakui)
- more prep work for runtime pm on Baytrail (Imre)
- eDram support for BDW (Ben)
- prep work for userptr support (Chris)
- first parts of the encoder->mode_set callback removal (Daniel)
- 64b reloc fixes (Ben)
- first part of atomic plane updates (Ville)
* tag 'drm-intel-next-2014-05-06' of git://anongit.freedesktop.org/drm-intel: (75 commits)
drm/i915: Remove useless checks from primary enable/disable
drm/i915: Merge LP1+ watermarks in safer way
drm/i915: Make sure computed watermarks never overflow the registers
drm/i915: Add pipe update trace points
drm/i915: Perform primary enable/disable atomically with sprite updates
drm/i915: Make sprite updates atomic
drm/i915: Support 64b relocations
drm/i915: Support 64b execbuf
drm/i915/sdvo: Remove ->mode_set callback
drm/i915/crt: Remove ->mode_set callback
drm/i915/tv: Remove ->mode_set callback
drm/i915/tv: Rip out pipe-disabling nonsense from ->mode_set
drm/i915/tv: De-magic device check
drm/i915/tv: extract set_color_conversion
drm/i915/tv: extract set_tv_mode_timings
drm/i915/dvo: Remove ->mode_set callback
drm/i915: Make encoder->mode_set callbacks optional
drm/i915: Make primary_enabled match the actual hardware state
drm/i915: Move ring_begin to signal()
drm/i915: Virtualize the ringbuffer signal func
...
Calling netif_carrier_{on,off} is sufficient. There is no need
to duplicate the carrier state in a driver specific flag.
Acked-by: Enrico Mioso <mrkiko.rs@gmail.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
Lots of devices request much larger buffers than reasonable. This
cause real problems for users of hosts with limited resources.
Reducing the default buffer size to 16kB for such devices is
a reasonable trade-off between allowing them to aggregate traffic
and avoiding memory exhaustion on resource restrained hosts.
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
To have an idea of the effects of the protocol coalescing
it's useful to have some counters showing the different
aspects.
Due to the asymmetrical usbnet interface the netdev
rx_bytes counter has been counting real received payload,
while the tx_bytes counter has included the NCM/MBIM
framing overhead. This overhead can be many times the
payload because of the aggressive padding strategy of
this driver, and will vary a lot depending on device
and traffic.
With very few exceptions, users are only interested in
the payload size. Having an somewhat accurate payload
byte counter is particularly important for mobile
broadband devices, which many NCM devices and of course
all MBIM devices are. Users and userspace applications
will use this counter to monitor account quotas.
Having protocol specific counters for the overhead, we are
now able to correct the tx_bytes netdev counter so that
it shows the real payload
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
We pad frames larger than X to maximum size for devices which
don't need a ZLP after maximum sized frames. This allows the
device to optimize its transfers for one fixed buffer size.
X was arbitrarily set at 512 bytes regardless of real buffer
maximum, causing extreme overheads due to excessive padding of
larger tx buffers. Limit the padding to at most 3 full USB
packets, still allowing the overhead to payload ratio of 3/1.
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
Many newer NCM and MBIM devices will request a maximum tx
datagram count which is much smaller than our hard-coded
absolute max. We can reduce the overhead without sacrificing
any of the simplicity for these devices, by simply using the
true negotiated count in when calculated the maximum NTH and
NDP header sizes.
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
Datagram coalescing is an integral part of the NCM and MBIM
protocols, intended to reduce the interrupt load primarily
on the device end of the USB link. As with all coalescing
solutions, there is a trade-off between buffering and
interrupts.
The current defaults are based on the assumption that device
side buffers should be the limiting factor. However, many
modern high speed LTE modems suffers from buffer-bloat,
making this assumption fail. This results in sub-optimal
performance due to excessive coalescing. And in cases where
such modems are connected to cheap embedded hosts there is
often severe buffer allocation issues, giving very noticeable
performance degradation .
A start on improving this is going from build time hard
coded limits to per device user configurable limits. The
ethtool coalescing API was selected as user interface
because, although the tuned values are buffer sizes, these
settings directly control datagram coalescing.
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
Prior to commit fbd929f2dc
bonding: support QinQ for bond arp interval
the arp monitoring code allowed for proper detection of devices
stacked on top of vlans. Since the above commit, the
code can still detect a device stacked on top of single
vlan, but not a device stacked on top of Q-in-Q configuration.
The search will only set the inner vlan tag if the route
device is the vlan device. However, this is not always the
case, as it is possible to extend the stacked configuration.
With this patch it is possible to provision devices on
top Q-in-Q vlan configuration that should be used as
a source of ARP monitoring information.
For example:
ip link add link bond0 vlan10 type vlan proto 802.1q id 10
ip link add link vlan10 vlan100 type vlan proto 802.1q id 100
ip link add link vlan100 type macvlan
Note: This patch limites the number of stacked VLANs to 2,
just like before. The original, however had another issue
in that if we had more then 2 levels of VLANs, we would end
up generating incorrectly tagged traffic. This is no longer
possible.
Fixes: fbd929f2dc (bonding: support QinQ for bond arp interval)
CC: Jay Vosburgh <j.vosburgh@gmail.com>
CC: Veaceslav Falico <vfalico@redhat.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: Ding Tianhong <dingtianhong@huawei.com>
CC: Patric McHardy <kaber@trash.net>
Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit dc8eaaa006.
vlan: Fix lockdep warning when vlan dev handle notification
Instead we use the new new API to find the lock subclass of
our vlan device. This way we can support configurations where
vlans are interspersed with other devices:
bond -> vlan -> macvlan -> vlan
Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently netif_addr_lock_nested assumes that there can be only
a single nesting level between 2 devices. However, if we
have multiple devices of the same type stacked, this fails.
For example:
eth0 <-- vlan0.10 <-- vlan0.10.20
A more complicated configuration may stack more then one type of
device in different order.
Ex:
eth0 <-- vlan0.10 <-- macvlan0 <-- vlan1.10.20 <-- macvlan1
This patch adds an ndo_* function that allows each stackable
device to report its nesting level. If the device doesn't
provide this function default subclass of 1 is used.
Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Multiple devices in the kernel can be stacked/nested and they
need to know their nesting level for the purposes of lockdep.
This patch provides a generic function that determines a nesting
level of a particular device by its type (ex: vlan, macvlan, etc).
We only care about nesting of the same type of devices.
For example:
eth0 <- vlan0.10 <- macvlan0 <- vlan1.20
The nesting level of vlan1.20 would be 1, since there is another vlan
in the stack under it.
Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Merge "at91: cleanup for 3.16 #1" from Nicolas Ferre:
First cleanup series for 3.15
- localize GPIO header in mach-at91 directory
- big update on the CCF front with main and slow clocks
- a cleanup of ADC and touchscreen driver with unification on IIO and
removal of old driver
[olof: Most of this branch is new code, not cleanups, so I'm merging this into
the SoC branch in spite of the branch name]
* tag 'at91-cleanup' of git://github.com/at91linux/linux-at91: (28 commits)
ARM: at91/dt: at91-cosino_mega2560 remove useless tsadcc node
ARM: at91: remove atmel_tsadcc platform_data
Input: atmel_tsadcc: remove driver
ARM: at91: remove atmel_tsadcc from sama5_defconfig
ARM: at91: sam9rl: switch from atmel_tsadcc to at91_adc
ARM: at91: sam9g45: switch from atmel_tsadcc to at91_adc
ARM: at91: sam9rlek add touchscreen support through at91_adc
ARM: at91: sam9rl: add at91_adc to support adc and touchscreen
iio: adc: at91: add sam9rl support
iio: adc: at91: remove unused include from include/mach
ARM: at91: sam9m10g45ek: Add touchscreen support through at91_adc
iio: adc: at91_adc: Add support for touchscreens without TSMR
iio: adc: at91: cleanup platform_data
ARM: at91: sam9260: remove unused platform_data
ARM: at91: sam9g45: remove unused platform_data
ARM: at91/dt: define sam9rlek crystal frequencies
ARM: at91/dt: move at91sam9rl SoC to the new slow/main clock models
ARM: at91/dt: define main xtal frequency of the at91sam9261ek board
ARM: at91/dt: move at91sam9261 SoC to the new main clock model
ARM: at91/dt: add xtal frequencies to sama5d3 xplained board
...
Signed-off-by: Olof Johansson <olof@lixom.net>
Merge "dts: socfpga: general updates for the socfpga platform" from Dinh
Nguyen:
Mostly DTS additions to the SOCFPGA platform from Steffan Trumtrar, and a
couple of device tree documentation updates/typo fix.
This one does not the GPIO binding patch, as that is pending further
discussion. Also, v3 fixes a rebase artifact and compile tested.
* tag 'socfpga-dt-updates-for-3.16_v3' of git://git.rocketboards.org/linux-socfpga-next:
ARM: socfpga: dts: Add div-reg to the main_pll clocks
ARM: socfpga: dts: add reset-controller
Documentation: dt: reset: move socfpga-reset
Documentation: dt: socfpga: add reset-cells property
ARM: socfpga: dts: Add DTS entries for USB
ARM: socfpga: dts: Remove hard coded clock-frequency property
ARM: socfpga: dts: add eeprom and rtc on i2c0
ARM: socfpga: dts: convert to preprocessor includes
ARM: socfpga: dts: add rtc on i2c0 to socrates
ARM: socfpga: dts: add support for EBV SOCrates
ARM: socfpga: dts: add can0+1
ARM: socfpga: dts: add i2c busses
ARM: socfpga: dts: add remaining interrupts for pdma
ARM: socfpga: dts: fix pdma interrupt
Signed-off-by: Olof Johansson <olof@lixom.net>
The 802.15.4-2011 standard states that for each key, a list of devices
that use this key shall be kept. Previous patches have only considered
two options:
* a device "uses" (or may use) all keys, rendering the list useless
* a device is restricted to a certain set of keys
Another option would be that a device *may* use all keys, but need not
do so, and we are interested in the actual set of keys the device uses.
Recording keys used by any given device may have a noticable performance
impact and might not be needed as often. The common case, in which a
device will not switch keys too often, should still perform well.
Signed-off-by: Phoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds user-visible interfaces for the llsec infrastructure.
For the added methods, the only major difference between all add/remove
implementation lies in how the specific object is parsed, and for dump
requests, how objects are written into netlink messages.
To save on boilerplate code, table dumps are routed through a helper
function that handles netlink dump state, leaving the actual dumping
code to care only about iterating over the table to be dumped and
filling netlink messages. For add/remove methods, the boilerplate
required to work is not quite as large, but still enough to also move
into a local helper.
Signed-off-by: Phoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Allow datagram sockets to override the security settings of the device
they send from on a per-socket basis. Requires CAP_NET_ADMIN or
CAP_NET_RAW, since raw sockets can send arbitrary packets anyway.
Signed-off-by: Phoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The added structures match 802.15.4-2011 link-layer security PIBs as
closely as is reasonable. Some lists required by the standard were
modeled as bitmaps (frame_types and command_frame_ids in *llsec_key,
802.15.4-2011 7.5/Table 61), since using lists for those seems a bit
excessive and not particularly useful. The DeviceDescriptorHandleList
was inverted and is here a per-device list, since operations on this
list are likely to have both a key and a device at hand, and per-device
lists of keys are shorter than per-key lists of devices.
Signed-off-by: Phoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some Ethernet MACs have a "fixed link", and are not connected to a
normal MDIO-managed PHY device. For those situations, a Device Tree
binding allows to describe a "fixed link" using a special PHY node.
This patch adds:
* A documentation for the fixed PHY Device Tree binding.
* An of_phy_is_fixed_link() function that an Ethernet driver can call
on its PHY phandle to find out whether it's a fixed link PHY or
not. It should typically be used to know if
of_phy_register_fixed_link() should be called.
* An of_phy_register_fixed_link() function that instantiates the
fixed PHY into the PHY subsystem, so that when the driver calls
of_phy_connect(), the PHY device associated to the OF node will be
found.
These two additional functions also support the old fixed-link Device
Tree binding used on PowerPC platforms, so that ultimately, the
network device drivers for those platforms could be converted to use
of_phy_is_fixed_link() and of_phy_register_fixed_link() instead of
of_phy_connect_fixed_link(), while keeping compatibility with their
respective Device Tree bindings.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The existing fixed_phy_add() function has several drawbacks that
prevents it from being used as is for OF-based declaration of fixed
PHYs:
* The address of the PHY on the fake bus needs to be passed, while a
dynamic allocation is desired.
* Since the phy_device instantiation is post-poned until the next
mdiobus scan, there is no way to associate the fixed PHY with its
OF node, which later prevents of_phy_connect() from finding this
fixed PHY from a given OF node.
To solve this, this commit introduces fixed_phy_register(), which will
allocate an available PHY address, add the PHY using fixed_phy_add()
and instantiate the phy_device structure associated with the provided
OF node.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Grant Likely <grant.likely@linaro.org>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, some subsystems (e.g. PCI and the ACPI PM domain) have to
resume all runtime-suspended devices during system suspend, mostly
because those devices may need to be reprogrammed due to different
wakeup settings for system sleep and for runtime PM.
For some devices, though, it's OK to remain in runtime suspend
throughout a complete system suspend/resume cycle (if the device was in
runtime suspend at the start of the cycle). We would like to do this
whenever possible, to avoid the overhead of extra power-up and power-down
events.
However, problems may arise because the device's descendants may require
it to be at full power at various points during the cycle. Therefore the
most straightforward way to do this safely is if the device and all its
descendants can remain runtime suspended until the complete stage of
system resume.
To this end, introduce a new device PM flag, power.direct_complete
and modify the PM core to use that flag as follows.
If the ->prepare() callback of a device returns a positive number,
the PM core will regard that as an indication that it may leave the
device runtime-suspended. It will then check if the system power
transition in progress is a suspend (and not hibernation in particular)
and if the device is, indeed, runtime-suspended. In that case, the PM
core will set the device's power.direct_complete flag. Otherwise it
will clear power.direct_complete for the device and it also will later
clear it for the device's parent (if there's one).
Next, the PM core will not invoke the ->suspend() ->suspend_late(),
->suspend_irq(), ->resume_irq(), ->resume_early(), or ->resume()
callbacks for all devices having power.direct_complete set. It
will invoke their ->complete() callbacks, however, and those
callbacks are then responsible for resuming the devices as
appropriate, if necessary. For example, in some cases they may
need to queue up runtime resume requests for the devices using
pm_request_resume().
Changelog partly based on an Alan Stern's description of the idea
(http://marc.info/?l=linux-pm&m=139940466625569&w=2).
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
John W. Linville says:
====================
pull request: wireless 2014-05-15
Please pull this batch of fixes for the 3.15 stream...
For the mac80211 bits, Johannes says:
"One fix is to get better VHT performance and the other fixes tracing
garbage or other potential issues with the interface name tracing."
And...
"This has a fix from Emmanuel for a problem I failed to fix - when
association is in progress then it needs to be cancelled while
suspending (I had fixed the same for authentication). Also included a
fix from myself for a userspace API problem that hit the iw tool and a
fix to the remain-on-channel framework."
For the iwlwifi bits, Emmanuel says:
"Alex fixes the scan by disabling the fragmented scan. David prevents
scan offload while associated, the firmware seems not to like it. I
fix a stupid bug I made in BT Coex, and fix a bad #ifdef clause in rate
scaling. Along with that there is a fix for a NULL pointer exception
that can happen if we load the driver and our ISR gets called because
the interrupt line is shared. The fix has been tested by the reporter."
And...
"We have here a fix from David Spinadel that makes a previous fix more
complete, and an off-by-one issue fixed by Eliad in the same area.
I fix the monitor that broke on the way."
Beyond that...
Daniel Kim's one-liner fixes a brcmfmac regression caused by a typo
in an earlier commit..
Rajkumar Manoharan fixes an ath9k oops reported by David Herrmann.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds UPDATE_QP SRIOV wrapper support.
The mechanism is a general one, but currently only source MAC
index changes are allowed for VFs.
Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This eliminates a 1-bit left shift in every single caller,
and makes the inner loop of the CRC computation more efficient.
Renamed crc7 to crc7_be (big-endian) since the interface changed.
Also purged #include <linux/crc7.h> from files that don't use it at all.
Signed-off-by: George Spelvin <linux@horizon.com>
Reviewed-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
By exporting the ability to map user address and inserting PTEs
representing their backing pages into the GTT, we can exploit UMA in order
to utilize normal application data as a texture source or even as a
render target (depending upon the capabilities of the chipset). This has
a number of uses, with zero-copy downloads to the GPU and efficient
readback making the intermixed streaming of CPU and GPU operations
fairly efficient. This ability has many widespread implications from
faster rendering of client-side software rasterisers (chromium),
mitigation of stalls due to read back (firefox) and to faster pipelining
of texture data (such as pixel buffer objects in GL or data blobs in CL).
v2: Compile with CONFIG_MMU_NOTIFIER
v3: We can sleep while performing invalidate-range, which we can utilise
to drop our page references prior to the kernel manipulating the vma
(for either discard or cloning) and so protect normal users.
v4: Only run the invalidate notifier if the range intercepts the bo.
v5: Prevent userspace from attempting to GTT mmap non-page aligned buffers
v6: Recheck after reacquire mutex for lost mmu.
v7: Fix implicit padding of ioctl struct by rounding to next 64bit boundary.
v8: Fix rebasing error after forwarding porting the back port.
v9: Limit the userptr to page aligned entries. We now expect userspace
to handle all the offset-in-page adjustments itself.
v10: Prevent vma from being copied across fork to avoid issues with cow.
v11: Drop vma behaviour changes -- locking is nigh on impossible.
Use a worker to load user pages to avoid lock inversions.
v12: Use get_task_mm()/mmput() for correct refcounting of mm.
v13: Use a worker to release the mmu_notifier to avoid lock inversion
v14: Decouple mmu_notifier from struct_mutex using a custom mmu_notifer
with its own locking and tree of objects for each mm/mmu_notifier.
v15: Prevent overlapping userptr objects, and invalidate all objects
within the mmu_notifier range
v16: Fix a typo for iterating over multiple objects in the range and
rearrange error path to destroy the mmu_notifier locklessly.
Also close a race between invalidate_range and the get_pages_worker.
v17: Close a race between get_pages_worker/invalidate_range and fresh
allocations of the same userptr range - and notice that
struct_mutex was presumed to be held when during creation it wasn't.
v18: Sigh. Fix the refactor of st_set_pages() to allocate enough memory
for the struct sg_table and to clear it before reporting an error.
v19: Always error out on read-only userptr requests as we don't have the
hardware infrastructure to support them at the moment.
v20: Refuse to implement read-only support until we have the required
infrastructure - but reserve the bit in flags for future use.
v21: use_mm() is not required for get_user_pages(). It is only meant to
be used to fix up the kernel thread's current->mm for use with
copy_user().
v22: Use sg_alloc_table_from_pages for that chunky feeling
v23: Export a function for sanity checking dma-buf rather than encode
userptr details elsewhere, and clean up comments based on
suggestions by Bradley.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: "Gong, Zhipeng" <zhipeng.gong@intel.com>
Cc: Akash Goel <akash.goel@intel.com>
Cc: "Volkin, Bradley D" <bradley.d.volkin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Reviewed-by: Brad Volkin <bradley.d.volkin@intel.com>
[danvet: Frob ioctl allocation to pick the next one - will cause a bit
of fuss with create2 apparently, but such are the rules.]
[danvet2: oops, forgot to git add after manual patch application]
[danvet3: Appease sparse.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Implement css_tryget() which tries to grab a cgroup_subsys_state's
reference as long as it already hasn't reached zero. Combined with
the recent css iterator changes to include offline && !released csses
during traversal, this can be used to access csses regardless of its
online state.
v2: Take the new flag CSS_NO_REF into account.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Now that cgroup liveliness and css onliness are the same state,
convert cgroup_has_live_children() into css_has_online_children() so
that it can be used for actual csses too. The function now uses
css_for_each_child() for iteration and is published.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Use CSS_ONLINE on the self css to indicate whether a cgroup has been
killed instead of CGRP_DEAD. This will allow re-using css online test
for cgroup liveliness test. This doesn't introduce any functional
change.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Currently, css_next_child() is implemented as finding the next child
cgroup which has the css enabled, which used to be the only way to do
it as only cgroups participated in sibling lists and thus could be
iteratd. This works as long as what's required during iteration is
not missing online csses; however, it turns out that there are use
cases where offlined but not yet released csses need to be iterated.
This is difficult to implement through cgroup iteration the unified
hierarchy as there may be multiple dying csses for the same subsystem
associated with single cgroup.
After the recent changes, the cgroup self and regular csses behave
identically in how they're linked and unlinked from the sibling lists
including assertion of CSS_RELEASED and css_next_child() can simply
switch to iterating csses directly. This both simplifies the logic
and ensures that all visible non-released csses are included in the
iteration whether there are multiple dying csses for a subsystem or
not.
As all other iterators depend on css_next_child() for sibling
iteration, this changes behaviors of all css iterators. Add and
update explanations on the css states which are included in traversal
to all iterators.
As css iteration could always contain offlined csses, this shouldn't
break any of the current users and new usages which need iteration of
all on and offline csses can make use of the new semantics.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
css iterations allow the caller to drop RCU read lock. As long as the
caller keeps the current position accessible, it can simply re-grab
RCU read lock later and continue iteration. This is achieved by using
CGRP_DEAD to detect whether the current positions next pointer is safe
to dereference and if not re-iterate from the beginning to the next
position using ->serial_nr.
CGRP_DEAD is used as the marker to invalidate the next pointer and the
only requirement is that the marker is set before the next sibling
starts its RCU grace period. Because CGRP_DEAD is set at the end of
cgroup_destroy_locked() but the cgroup is unlinked when the reference
count reaches zero, we currently have a rather large window where this
fallback re-iteration logic can be triggered.
This patch introduces CSS_RELEASED which is set when a css is unlinked
from its sibling list. This still keeps the re-iteration logic
working while drastically reducing the window of its activation.
While at it, rewrite the comment in css_next_child() to reflect the
new flag and better explain the synchronization.
This will also enable iterating csses directly instead of through
cgroups.
v2: CSS_RELEASED now assigned to 1 << 2 as 1 << 0 is used by
CSS_NO_REF.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
We're moving towards using cgroup_subsys_states as the fundamental
structural blocks. All csses including the cgroup->self and actual
ones now form trees through css->children and ->sibling which follow
the same rules as what cgroup->children and ->sibling followed. This
patch moves cgroup->serial_nr which is used to implement css iteration
into css.
Note that all csses, regardless of their types, allocate their serial
numbers from the same monotonically increasing counter. This doesn't
affect the ordering needed by css iteration or cause any other
material behavior changes. This will be used to update css iteration.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
We're moving towards using cgroup_subsys_states as the fundamental
structural blocks. Let's move cgroup->sibling and ->children into
cgroup_subsys_state. This is pure move without functional change and
only cgroup->self's fields are actually used. Other csses will make
use of the fields later.
While at it, update init_and_link_css() so that it zeroes the whole
css before initializing it and remove explicit zeroing of ->flags.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
cgroup->parent is redundant as cgroup->self.parent can also be used to
determine the parent cgroup and we're moving towards using
cgroup_subsys_states as the fundamental structural blocks. This patch
introduces cgroup_parent() which follows cgroup->self.parent and
removes cgroup->parent.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
cgroup in general is moving towards using cgroup_subsys_state as the
fundamental structural component and css_parent() was introduced to
convert from using cgroup->parent to css->parent. It was quite some
time ago and we're moving forward with making css more prominent.
This patch drops the trivial wrapper css_parent() and let the users
dereference css->parent. While at it, explicitly mark fields of css
which are public and immutable.
v2: New usage from device_cgroup.c converted.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: "David S. Miller" <davem@davemloft.net>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Johannes Weiner <hannes@cmpxchg.org>
9395a45004 ("cgroup: enable refcnting for root csses") enabled
reference counting for root csses (cgroup_subsys_states) so that
cgroup's self csses can be used to manage the lifetime of the
containing cgroups.
Unfortunately, this change was incorrect. During early init,
cgrp_dfl_root self css refcnt is used. percpu_ref can't initialized
during early init and its initialization is deferred till
cgroup_init() time. This means that cpu was using percpu_ref which
wasn't properly initialized. Due to the way percpu variables are laid
out on x86, this didn't blow up immediately on x86 but ended up
incrementing and decrementing the percpu variable at offset zero,
whatever it may be; however, on other archs, this caused fault and
early boot failure.
As cgroup self csses for root cgroups of non-dfl hierarchies need
working refcounting, we can't revert 9395a45004. This patch adds
CSS_NO_REF which explicitly inhibits reference counting on the css and
sets it on all normal (non-self) csses and cgroup_dfl_root self css.
v2: cgrp_dfl_root.self is the offending one. Set the flag on it.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
Fixes: 9395a45004 ("cgroup: enable refcnting for root csses")
Today's linux-next kernel started showing build errors for the
use of WARN_ON in linux/gpio/consumer.h:
In file included from drivers/video/backlight/pwm_bl.c:13:0:
include/linux/gpio/consumer.h: In function 'gpiod_put':
include/linux/gpio/consumer.h:81:2: error: implicit declaration of function 'WARN_ON' [-Werror=implicit-function-declaration]
It's not clear why this never happened before, but this patch
fixes it by including the header that contains the defintion
of this macro.
Signed-off-by: Arnd Bergmann <arnd@arnd.de>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Not really the solution to the problem, but at least it confines the
mess in the core code and allows to get rid of the create/destroy_irq
variants from hell, i.e. 3 implementations with different semantics
plus the x86 specific variants __create_irqs and create_irq_nr
which have been invented in another circle of hell.
x86 : x86 should be converted to irq domains and I'm deliberately
making it impossible to do the multi-vector MSI support by
adding more crap to the current mess. It's not that hard to do
and I'm really tired of the trainwrecks which have been invented
by baindaid engineering so far. Any attempt to do multi-vector
MSI or ioapic hotplug without converting to irq domains is NAKed
hereby.
tile: Might use irq domains as well, but it has a very limited
interrupt space, so handling it via this functionality might be
the right thing to do even in the long run.
ia64: That's an hopeless case, as I doubt that anyone has the stomach
to rewrite the homebrewn dynamic allocation facilities. I stared
at it for a couple of hours and gave up. The create/destroy_irq
mess could be made private to itanic right away if there
wouldn't be the iommu/dmar driver being shared with x86. So to
do that I'm going to add a separate ia64 specific implementation
later in order not to deep-six itanic right away.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Grant Likely <grant.likely@linaro.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20140507154334.208629358@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The "freeze" sleep state suffers from the same issue that was
addressed by commit ad07277e82 (ACPI / PM: Hold acpi_scan_lock over
system PM transitions) for ACPI sleep states, that is, things break
if ->remove() is called for devices whose system resume callbacks
haven't been executed yet.
It also can be addressed in the same way, by holding the ACPI scan
lock over the "freeze" sleep state and PM transitions to and from
that state, but ->begin() and ->end() platform operations for the
"freeze" sleep state are needed for this purpose.
This change has been tested on Acer Aspire S5 with Thunderbolt.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
FPSIMD register bank context switching and crypto algorithms
optimisations for arm64 from Ard Biesheuvel.
* tag 'for-3.16' of git://git.linaro.org/people/ard.biesheuvel/linux-arm:
arm64/crypto: AES-ECB/CBC/CTR/XTS using ARMv8 NEON and Crypto Extensions
arm64: pull in <asm/simd.h> from asm-generic
arm64/crypto: AES in CCM mode using ARMv8 Crypto Extensions
arm64/crypto: AES using ARMv8 Crypto Extensions
arm64/crypto: GHASH secure hash using ARMv8 Crypto Extensions
arm64/crypto: SHA-224/SHA-256 using ARMv8 Crypto Extensions
arm64/crypto: SHA-1 using ARMv8 Crypto Extensions
arm64: add support for kernel mode NEON in interrupt context
arm64: defer reloading a task's FPSIMD state to userland resume
arm64: add abstractions for FPSIMD state manipulation
asm-generic: allow generic unaligned access if the arch supports it
Conflicts:
arch/arm64/include/asm/thread_info.h
