Some of the helper functions return negative error codes if
passed a NULL clock. This can lead to confusing behavior when the
expected return value is unsigned. Fix up these accessors so that
they return unsigned values (or bool in the case of is_enabled).
This way we can't interpret NULL clocks as having valid and
interesting values.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Fix some minor typos in the documentation for the ops structure.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
This pulls in all of the USB changes in 3.7-rc3 into usb-next and
resolves the merge issue with:
drivers/usb/misc/ezusb.c
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This resolves the conflict with:
drivers/staging/comedi/drivers/amplc_dio200.c
and syncs up the changes that happened in the staging directory for
3.7-rc3.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This merges the old <plat/pincfg.h> header into
<linux/platform_data/pinctrl-nomadik.h> and rids us of
yet one more <plat/*> include.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This moves the platform data header for the Nomadik pin controller
to <linux/platform_data/pinctrl-nomadik.h>.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Use rcu_read_lock_sched / rcu_read_unlock_sched / synchronize_sched
instead of rcu_read_lock / rcu_read_unlock / synchronize_rcu.
This is an optimization. The RCU-protected region is very small, so
there will be no latency problems if we disable preempt in this region.
So we use rcu_read_lock_sched / rcu_read_unlock_sched that translates
to preempt_disable / preempt_disable. It is smaller (and supposedly
faster) than preemptible rcu_read_lock / rcu_read_unlock.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch introduces new barrier pair light_mb() and heavy_mb() for
percpu rw semaphores.
This patch fixes a bug in percpu-rw-semaphores where a barrier was
missing in percpu_up_write.
This patch improves performance on the read path of
percpu-rw-semaphores: on non-x86 cpus, there was a smp_mb() in
percpu_up_read. This patch changes it to a compiler barrier and removes
the "#if defined(X86) ..." condition.
From: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In old days, we had two different API sets for dynamic-allocated per-CPU
data and DEFINE_PER_CPU()-defined per_cpu data, and because SRCU used
dynamic-allocated per-CPU data, its srcu_struct structures cannot be
declared statically. This commit therefore introduces DEFINE_SRCU()
and DEFINE_STATIC_SRCU() to allow statically declared SRCU structures,
using the new static per-CPU interfaces.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Updated for __DELAYED_WORK_INITIALIZER() added argument,
fixed whitespace issue. ]
Remove the use of the private DaVinci SRAM API in favor
of genalloc. The pool to be used is provided by platform
data.
Signed-off-by: Matt Porter <mporter@ti.com>
Signed-off-by: "Hans J. Koch" <hjk@hansjkoch.de>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Pull networking fixes from David Miller:
"This is what we usually expect at this stage of the game, lots of
little things, mostly in drivers. With the occasional 'oops didn't
mean to do that' kind of regressions in the core code."
1) Uninitialized data in __ip_vs_get_timeouts(), from Arnd Bergmann
2) Reject invalid ACK sequences in Fast Open sockets, from Jerry Chu.
3) Lost error code on return from _rtl_usb_receive(), from Christian
Lamparter.
4) Fix reset resume on USB rt2x00, from Stanislaw Gruszka.
5) Release resources on error in pch_gbe driver, from Veaceslav Falico.
6) Default hop limit not set correctly in ip6_template_metrics[], fix
from Li RongQing.
7) Gianfar PTP code requests wrong kind of resource during probe, fix
from Wei Yang.
8) Fix VHOST net driver on big-endian, from Michael S Tsirkin.
9) Mallenox driver bug fixes from Jack Morgenstein, Or Gerlitz, Moni
Shoua, Dotan Barak, and Uri Habusha.
10) usbnet leaks memory on TX path, fix from Hemant Kumar.
11) Use socket state test, rather than presence of FIN bit packet, to
determine FIONREAD/SIOCINQ value. Fix from Eric Dumazet.
12) Fix cxgb4 build failure, from Vipul Pandya.
13) Provide a SYN_DATA_ACKED state to complement SYN_FASTOPEN in socket
info dumps. From Yuchung Cheng.
14) Fix leak of security path in kfree_skb_partial(). Fix from Eric
Dumazet.
15) Handle RX FIFO overflows more resiliently in pch_gbe driver, from
Veaceslav Falico.
16) Fix MAINTAINERS file pattern for networking drivers, from Jean
Delvare.
17) Add iPhone5 IDs to IPHETH driver, from Jay Purohit.
18) VLAN device type change restriction is too strict, and should not
trigger for the automatically generated vlan0 device. Fix from Jiri
Pirko.
19) Make PMTU/redirect flushing work properly again in ipv4, from
Steffen Klassert.
20) Fix memory corruptions by using kfree_rcu() in netlink_release().
From Eric Dumazet.
21) More qmi_wwan device IDs, from Bjørn Mork.
22) Fix unintentional change of SNAT/DNAT hooks in generic NAT
infrastructure, from Elison Niven.
23) Fix 3.6.x regression in xt_TEE netfilter module, from Eric Dumazet.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (57 commits)
tilegx: fix some issues in the SW TSO support
qmi_wwan/cdc_ether: move Novatel 551 and E362 to qmi_wwan
net: usb: Fix memory leak on Tx data path
net/mlx4_core: Unmap UAR also in the case of error flow
net/mlx4_en: Don't use vlan tag value as an indication for vlan presence
net/mlx4_en: Fix double-release-range in tx-rings
bas_gigaset: fix pre_reset handling
vhost: fix mergeable bufs on BE hosts
gianfar_ptp: use iomem, not ioports resource tree in probe
ipv6: Set default hoplimit as zero.
NET_VENDOR_TI: make available for am33xx as well
pch_gbe: fix error handling in pch_gbe_up()
b43: Fix oops on unload when firmware not found
mwifiex: clean up scan state on error
mwifiex: return -EBUSY if specific scan request cannot be honored
brcmfmac: fix potential NULL dereference
Revert "ath9k_hw: Updated AR9003 tx gain table for 5GHz"
ath9k_htc: Add PID/VID for a Ubiquiti WiFiStation
rt2x00: usb: fix reset resume
rtlwifi: pass rx setup error code to caller
...
try_to_freeze_tasks() and cgroup_freezer rely on scheduler locks
to ensure that a task doing STOPPED/TRACED -> RUNNING transition
can't escape freezing. This mostly works, but ptrace_stop() does
not necessarily call schedule(), it can change task->state back to
RUNNING and check freezing() without any lock/barrier in between.
We could add the necessary barrier, but this patch changes
ptrace_stop() and do_signal_stop() to use freezable_schedule().
This fixes the race, freezer_count() and freezer_should_skip()
carefully avoid the race.
And this simplifies the code, try_to_freeze_tasks/update_if_frozen
no longer need to use task_is_stopped_or_traced() checks with the
non trivial assumptions. We can rely on the mechanism which was
specially designed to mark the sleeping task as "frozen enough".
v2: As Tejun pointed out, we can also change get_signal_to_deliver()
and move try_to_freeze() up before 'relock' label.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Pull staging driver fixes from Greg Kroah-Hartman:
"Here are some staging driver fixes for your 3.7-rc tree.
Nothing major here, a number of iio driver fixups that were causing
problems, some comedi driver bugfixes, and a bunch of tidspbridge
warning squashing and other regressions fixed from the 3.6 release.
All have been in the linux-next releases for a bit.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
* tag 'staging-3.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (32 commits)
staging: tidspbridge: delete unused mmu functions
staging: tidspbridge: ioremap physical address of the stack segment in shm
staging: tidspbridge: ioremap dsp sync addr
staging: tidspbridge: change type to __iomem for per and core addresses
staging: tidspbridge: drop const from custom mmu implementation
staging: tidspbridge: request the right irq for mmu
staging: ipack: add missing include (implicit declaration of function 'kfree')
staging: ramster: depends on NET
staging: omapdrm: fix allocation size for page addresses array
staging: zram: Fix handling of incompressible pages
Staging: android: binder: Allow using highmem for binder buffers
Staging: android: binder: Fix memory leak on thread/process exit
staging: comedi: ni_labpc: fix possible NULL deref during detach
staging: comedi: das08: fix possible NULL deref during detach
staging: comedi: amplc_pc263: fix possible NULL deref during detach
staging: comedi: amplc_pc236: fix possible NULL deref during detach
staging: comedi: amplc_pc236: fix invalid register access during detach
staging: comedi: amplc_dio200: fix possible NULL deref during detach
staging: comedi: 8255_pci: fix possible NULL deref during detach
staging: comedi: ni_daq_700: fix dio subdevice regression
...
Pull driver core fixes from Greg Kroah-Hartman:
"Here are a number of firmware core fixes for 3.7, and some other minor
fixes. And some documentation updates thrown in for good measure.
All have been in the linux-next tree for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
* tag 'driver-core-3.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
Documentation:Chinese translation of Documentation/arm64/memory.txt
Documentation:Chinese translation of Documentation/arm64/booting.txt
Documentation:Chinese translation of Documentation/IRQ.txt
firmware loader: document kernel direct loading
sysfs: sysfs_pathname/sysfs_add_one: Use strlcat() instead of strcat()
dynamic_debug: Remove unnecessary __used
firmware loader: sync firmware cache by async_synchronize_full_domain
firmware loader: let direct loading back on 'firmware_buf'
firmware loader: fix one reqeust_firmware race
firmware loader: cancel uncache work before caching firmware
Pull char/misc driver fixes from Greg Kroah-Hartman:
"Here are some driver fixes for 3.7. They include extcon driver fixes,
a hyper-v bugfix, and two other minor driver fixes.
All of these have been in the linux-next releases for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
* tag 'char-misc-3.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
sonypi: suspend/resume callbacks should be conditionally compiled on CONFIG_PM_SLEEP
Drivers: hv: Cleanup error handling in vmbus_open()
extcon : register for cable interest by cable name
extcon: trivial: kfree missed from remove path
extcon: driver model release call not needed
extcon: MAX77693: Add platform data for MUIC device to initialize registers
extcon: max77693: Use max77693_update_reg for rmw operations
extcon: Fix kerneldoc for extcon_set_cable_state and extcon_set_cable_state_
extcon: adc-jack: Add missing MODULE_LICENSE
extcon: adc-jack: Fix checking return value of request_any_context_irq
extcon: Fix return value in extcon_register_interest()
extcon: unregister compat link on cleanup
extcon: Unregister compat class at module unload to fix oops
extcon: optimising the check_mutually_exclusive function
extcon: standard cable names definition and declaration changed
extcon-max8997: remove usage of ret in max8997_muic_handle_charger_type_detach
extcon: Remove duplicate inclusion of extcon.h header file
Pull x86 fixes from Ingo Molnar:
"This fixes a couple of nasty page table initialization bugs which were
causing kdump regressions. A clean rearchitecturing of the code is in
the works - meanwhile these are reverts that restore the
best-known-working state of the kernel.
There's also EFI fixes and other small fixes."
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, mm: Undo incorrect revert in arch/x86/mm/init.c
x86: efi: Turn off efi_enabled after setup on mixed fw/kernel
x86, mm: Find_early_table_space based on ranges that are actually being mapped
x86, mm: Use memblock memory loop instead of e820_RAM
x86, mm: Trim memory in memblock to be page aligned
x86/irq/ioapic: Check for valid irq_cfg pointer in smp_irq_move_cleanup_interrupt
x86/efi: Fix oops caused by incorrect set_memory_uc() usage
x86-64: Fix page table accounting
Revert "x86/mm: Fix the size calculation of mapping tables"
MAINTAINERS: Add EFI git repository location
Pull perf fixes from Ingo Molnar:
"Most of the kernel diffstat relates to a group of Intel P6 and KNC
(Xeon-Phi Knights Corner) PMU driver fixes, neither of which is in
heavy use, so we took the fixes.
The rest is diverse smallish fixes to the tooling and kernel side."
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86: Remove unused variable in nhmex_rbox_alter_er()
perf/x86: Enable overflow on Intel KNC with a custom knc_pmu_handle_irq()
perf/x86: Remove cpuc->enable check on Intl KNC event enable/disable
perf/x86: Make Intel KNC use full 40-bit width of counters
perf/x86/uncore: Handle pci_read_config_dword() errors
perf/x86: Remove P6 cpuc->enabled check
perf/x86: Update/fix generic events on P6 PMU
perf/x86: Fix P6 FP_ASSIST event constraint
perf, cpu hotplug: Use cached value of smp_processor_id()
perf, cpu hotplug: Run CPU_STARTING notifiers with irqs disabled
x86/perf: Fix virtualization sanity check
perf test: Fix exclude_guest parse events tests
perf tools: do not flush maps on COMM for perf report
perf help: Fix --help for builtins
perf trace: Check if sample raw_data field is set
perf trace: Validate syscall id before growing syscall table
Pull x86 RAS changes from Borislav Petkov:
"Rework all config variables used throughout the MCA code and collect
them together into a mca_config struct. This keeps them tightly and
neatly packed together instead of spilled all over the place.
Then, convert those which are used as booleans into real booleans and
save some space."
Signed-off-by: Ingo Molnar <mingo@kernel.org>
... which, analogous to DEVICE_INT_ATTR provides functionality to
set/clear bools. Its purpose is to be used where values need to be used
as booleans in configuration context.
Next patch uses this.
Signed-off-by: Borislav Petkov <bp@alien8.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Tony Luck <tony.luck@intel.com>
This patch introduces the below 3 usb command helpers:
usbnet_read_cmd / usbnet_write_cmd / usbnet_write_cmd_async
so that each low level driver doesn't need to implement them
by itself, and the dma buffer allocation for usb transfer and
runtime PM things can be handled just in one place.
Acked-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
rb_erase_augmented() is a static function annotated with
__always_inline. This causes a compile failure when attempting to use
the rbtree implementation as a library (e.g. kvm tool):
rbtree_augmented.h:125:24: error: expected `=', `,', `;', `asm' or `__attribute__' before `void'
Include linux/compiler.h in rbtree_augmented.h so that the __always_inline
macro is resolved correctly.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Reviewed-by: Michel Lespinasse <walken@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull spi fixes from Mark Brown:
"A bunch of fixes here, mostly minor except for the pl022 which has
just been a bit of a shambles all round, the recent runtime PM changes
have as far as I can tell never worked so they're just getting thrown
out."
* tag 'spi-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/misc:
spi/pl022: Revert recent runtime PM changes
spi: tsc2005: delete soon-obsolete e-mail address
spi: spi-rspi: fix build error for the latest shdma driver
This device extends the uio_pdrv_genirq driver to provide limited
dynamic memory allocation for UIO devices. This allows UIO devices
to use CMA and IOMMU allocated memory regions. This driver is based
on the uio_pdrv_genirq driver and provides the same generic interrupt
handling capabilities. Like uio_prdv_genirq,
a fixed number of memory regions, defined in the platform device's
.resources field are exported to userpace. This driver adds the ability
to export additional regions whose number and size are known at boot time,
but whose memory is not allocated until the uio device file is opened for
the first time. When the device file is closed, the allocated memory block
is freed. Physical (DMA) addresses for the dynamic regions are provided to
the userspace via /sys/class/uio/uioX/maps/mapY/addr in the same way as
static addresses are when the uio device file is open, when no processes
are holding the device file open, the address returned to userspace is
DMA_ERROR_CODE.
Signed-off-by: Damian Hobson-Garcia <dhobsong@igel.co.jp>
Signed-off-by: "Hans J. Koch" <hjk@hansjkoch.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch (as1620) speeds up USB root-hub resumes in the common case
where every enabled port has its suspend feature set (which currently
will be true for every runtime resume of the root hub). If all the
enabled ports are suspended then resuming the root hub won't resume
any of the downstream devices. In this case there's no need for a
Resume Recovery delay, because that delay is meant to give devices a
chance to get ready for active use.
To keep track of the port suspend features, the patch adds a
"port_is_suspended" flag to struct usb_device. This has to be tracked
separately from the device's state; it's entirely possible for a USB-2
device to be suspended while the suspend feature on its parent port is
clear. The reason is that devices will go into suspend whenever their
parent hub does.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reviewed-by: Peter Chen <peter.chen@freescale.com>
Tested-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch (as1619) improves the interface to the "hub_for_each_child"
macro. The name clearly suggests that the macro iterates over child
devices; it does not suggest that the loop will also iterate over
unnconnected ports.
The patch changes the macro so that it will skip over unconnected
ports and iterate only the actual child devices. The two existing
call sites are updated to avoid testing for a NULL child pointer,
which is now unnecessary.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In order to make single zImage work for ARM architecture,
we need to make sure we don't depend on private headers.
Move USB platform_data to <linux/platform_data/omap-usb.h>
and add a minimal drivers/mfd/usb-omap.h.
Cc: Samuel Ortiz <sameo@linux.intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Partha Basak <parthab@india.ti.com>
Cc: Keshava Munegowda <keshava_mgowda@ti.com>
Cc: linux-usb@vger.kernel.org
Signed-off-by: Felipe Balbi <balbi@ti.com>
[tony@atomide.com: updated for local mfd/usb-omap.h]
Signed-off-by: Tony Lindgren <tony@atomide.com>
When the ezusb code was split out, support was added for the fx2 chip
type, but no one is using these functions, so comment it out. If
someone needs it, it can be added back in the future.
Also properly include <linux/usb/ezusb.h> into the ezusb.c file, to
ensure we catch any function prototype mis-matches
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: René Bürgel <rene.buergel@sohard.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is the first set of omap cleanup patches for v3.8 merge
window to remove most of the remaining plat includes to get us
closer to ARM common zImage support.
To avoid a huge amount of trivial merge conflicts with includes,
this branch is based on several small topic branches coordinated
with the driver subsystem maintainers. These branches are based on
v3.7-rc1 and can also be merged into the related driver subsystem
branches as needed:
omap-for-v3.8/cleanup-headers-prepare few trivial driver changes
omap-for-v3.8/cleanup-headers-dma move of the DMA header
omap-for-v3.8/cleanup-headers-gpmc GPMC and MTD changes
omap-for-v3.8/cleanup-headers-mmc MMC related changes
omap-for-v3.8/cleanup-headers-dss DSS related changes
omap-for-v3.8/cleanup-headers-asoc ASoC related changes
Note that for the dma-omap.h, it was decided that it should be
is completed. For the related discussion, please see:
https://patchwork.kernel.org/patch/1519591/#
After these patches we still have a few plat headers remaining
that will be handled in later pull requests.
Add dma-debug interface debug_dma_mapping_error() to debug
drivers that fail to check dma mapping errors on addresses
returned by dma_map_single() and dma_map_page() interfaces.
This interface clears a flag set by debug_dma_map_page() to
indicate that dma_mapping_error() has been called by the
driver. When driver does unmap, debug_dma_unmap() checks the
flag and if this flag is still set, prints warning message
that includes call trace that leads up to the unmap. This
interface can be called from dma_mapping_error() routines to
enable dma mapping error check debugging.
Tested: Intel iommu and swiotlb (iommu=soft) on x86-64 with
CONFIG_DMA_API_DEBUG enabled and disabled.
Signed-off-by: Shuah Khan <shuah.khan@hp.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Right now, slab and slub have fields in struct page to derive which
cache a page belongs to, but they do it slightly differently.
slab uses a field called slab_cache, that lives in the third double
word. slub, uses a field called "slab", living outside of the
doublewords area.
Ideally, we could use the same field for this. Since slub heavily makes
use of the doubleword region, there isn't really much room to move
slub's slab_cache field around. Since slab does not have such strict
placement restrictions, we can move it outside the doubleword area.
The naming used by slab, "slab_cache", is less confusing, and it is
preferred over slub's generic "slab".
Signed-off-by: Glauber Costa <glommer@parallels.com>
Acked-by: Christoph Lameter <cl@linux.com>
CC: David Rientjes <rientjes@google.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
While per-entity load-tracking is generally useful, beyond computing shares
distribution, e.g. runnable based load-balance (in progress), governors,
power-management, etc.
These facilities are not yet consumers of this data. This may be trivially
reverted when the information is required; but avoid paying the overhead for
calculations we will not use until then.
Signed-off-by: Paul Turner <pjt@google.com>
Reviewed-by: Ben Segall <bsegall@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120823141507.422162369@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Since we are now doing bottom up load accumulation we need explicit
notification when a task has been re-parented so that the old hierarchy can be
updated.
Adds: migrate_task_rq(struct task_struct *p, int next_cpu)
(The alternative is to do this out of __set_task_cpu, but it was suggested that
this would be a cleaner encapsulation.)
Signed-off-by: Paul Turner <pjt@google.com>
Reviewed-by: Ben Segall <bsegall@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120823141506.660023400@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We are currently maintaining:
runnable_load(cfs_rq) = \Sum task_load(t)
For all running children t of cfs_rq. While this can be naturally updated for
tasks in a runnable state (as they are scheduled); this does not account for
the load contributed by blocked task entities.
This can be solved by introducing a separate accounting for blocked load:
blocked_load(cfs_rq) = \Sum runnable(b) * weight(b)
Obviously we do not want to iterate over all blocked entities to account for
their decay, we instead observe that:
runnable_load(t) = \Sum p_i*y^i
and that to account for an additional idle period we only need to compute:
y*runnable_load(t).
This means that we can compute all blocked entities at once by evaluating:
blocked_load(cfs_rq)` = y * blocked_load(cfs_rq)
Finally we maintain a decay counter so that when a sleeping entity re-awakens
we can determine how much of its load should be removed from the blocked sum.
Signed-off-by: Paul Turner <pjt@google.com>
Reviewed-by: Ben Segall <bsegall@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120823141506.585389902@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
For a given task t, we can compute its contribution to load as:
task_load(t) = runnable_avg(t) * weight(t)
On a parenting cfs_rq we can then aggregate:
runnable_load(cfs_rq) = \Sum task_load(t), for all runnable children t
Maintain this bottom up, with task entities adding their contributed load to
the parenting cfs_rq sum. When a task entity's load changes we add the same
delta to the maintained sum.
Signed-off-by: Paul Turner <pjt@google.com>
Reviewed-by: Ben Segall <bsegall@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120823141506.514678907@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Instead of tracking averaging the load parented by a cfs_rq, we can track
entity load directly. With the load for a given cfs_rq then being the sum
of its children.
To do this we represent the historical contribution to runnable average
within each trailing 1024us of execution as the coefficients of a
geometric series.
We can express this for a given task t as:
runnable_sum(t) = \Sum u_i * y^i, runnable_avg_period(t) = \Sum 1024 * y^i
load(t) = weight_t * runnable_sum(t) / runnable_avg_period(t)
Where: u_i is the usage in the last i`th 1024us period (approximately 1ms)
~ms and y is chosen such that y^k = 1/2. We currently choose k to be 32 which
roughly translates to about a sched period.
Signed-off-by: Paul Turner <pjt@google.com>
Reviewed-by: Ben Segall <bsegall@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120823141506.372695337@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Define two device PM QoS flags, PM_QOS_FLAG_NO_POWER_OFF
and PM_QOS_FLAG_REMOTE_WAKEUP, and introduce routines
dev_pm_qos_expose_flags() and dev_pm_qos_hide_flags() allowing the
caller to expose those two flags to user space or to hide them
from it, respectively.
After the flags have been exposed, user space will see two
additional sysfs attributes, pm_qos_no_power_off and
pm_qos_remote_wakeup, under the device's /sys/devices/.../power/
directory. Then, writing 1 to one of them will update the
PM QoS flags request owned by user space so that the corresponding
flag is requested to be set. In turn, writing 0 to one of them
will cause the corresponding flag in the user space's request to
be cleared (however, the owners of the other PM QoS flags requests
for the same device may still request the flag to be set and it
may be effectively set even if user space doesn't request that).
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Jean Pihet <j-pihet@ti.com>
Acked-by: mark gross <markgross@thegnar.org>
The RCU CPU stall warnings rely on trigger_all_cpu_backtrace() to
do NMI-based dump of the stack traces of all CPUs. Unfortunately, a
number of architectures do not implement trigger_all_cpu_backtrace(), in
which case RCU falls back to just dumping the stack of the running CPU.
This is unhelpful in the case where the running CPU has detected that
some other CPU has stalled.
This commit therefore makes the running CPU dump the stacks of the
tasks running on the stalled CPUs.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Because process_srcu() will be used in DEFINE_SRCU(), which is a macro
that could be expanded pretty much anywhere, it can no longer be static.
Note that process_srcu() is still internal to srcu.h.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Lai Jiangshan rewrote SRCU, so this commit ensures that he gets his
proper share of blame^Wcredit.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
