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Merge 3.10-rc3 into usb-next
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We want these fixes.

Signed-off-by: Greg Kroah-Hartman <[email protected]>
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gregkh committed May 27, 2013
2 parents 3138887 + e4aa937 commit 45f6bc5
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2 changes: 1 addition & 1 deletion Documentation/devicetree/bindings/net/macb.txt
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Expand Up @@ -4,7 +4,7 @@ Required properties:
- compatible: Should be "cdns,[<chip>-]{macb|gem}"
Use "cdns,at91sam9260-macb" Atmel at91sam9260 and at91sam9263 SoCs.
Use "cdns,at32ap7000-macb" for other 10/100 usage or use the generic form: "cdns,macb".
Use "cnds,pc302-gem" for Picochip picoXcell pc302 and later devices based on
Use "cdns,pc302-gem" for Picochip picoXcell pc302 and later devices based on
the Cadence GEM, or the generic form: "cdns,gem".
- reg: Address and length of the register set for the device
- interrupts: Should contain macb interrupt
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25 changes: 25 additions & 0 deletions Documentation/devicetree/bindings/video/simple-framebuffer.txt
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@@ -0,0 +1,25 @@
Simple Framebuffer

A simple frame-buffer describes a raw memory region that may be rendered to,
with the assumption that the display hardware has already been set up to scan
out from that buffer.

Required properties:
- compatible: "simple-framebuffer"
- reg: Should contain the location and size of the framebuffer memory.
- width: The width of the framebuffer in pixels.
- height: The height of the framebuffer in pixels.
- stride: The number of bytes in each line of the framebuffer.
- format: The format of the framebuffer surface. Valid values are:
- r5g6b5 (16-bit pixels, d[15:11]=r, d[10:5]=g, d[4:0]=b).

Example:

framebuffer {
compatible = "simple-framebuffer";
reg = <0x1d385000 (1600 * 1200 * 2)>;
width = <1600>;
height = <1200>;
stride = <(1600 * 2)>;
format = "r5g6b5";
};
8 changes: 5 additions & 3 deletions Documentation/devicetree/usage-model.txt
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Expand Up @@ -191,9 +191,11 @@ Linux it will look something like this:
};

The bootargs property contains the kernel arguments, and the initrd-*
properties define the address and size of an initrd blob. The
chosen node may also optionally contain an arbitrary number of
additional properties for platform-specific configuration data.
properties define the address and size of an initrd blob. Note that
initrd-end is the first address after the initrd image, so this doesn't
match the usual semantic of struct resource. The chosen node may also
optionally contain an arbitrary number of additional properties for
platform-specific configuration data.

During early boot, the architecture setup code calls of_scan_flat_dt()
several times with different helper callbacks to parse device tree
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21 changes: 21 additions & 0 deletions Documentation/kernel-parameters.txt
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Expand Up @@ -3005,6 +3005,27 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Force threading of all interrupt handlers except those
marked explicitly IRQF_NO_THREAD.

tmem [KNL,XEN]
Enable the Transcendent memory driver if built-in.

tmem.cleancache=0|1 [KNL, XEN]
Default is on (1). Disable the usage of the cleancache
API to send anonymous pages to the hypervisor.

tmem.frontswap=0|1 [KNL, XEN]
Default is on (1). Disable the usage of the frontswap
API to send swap pages to the hypervisor. If disabled
the selfballooning and selfshrinking are force disabled.

tmem.selfballooning=0|1 [KNL, XEN]
Default is on (1). Disable the driving of swap pages
to the hypervisor.

tmem.selfshrinking=0|1 [KNL, XEN]
Default is on (1). Partial swapoff that immediately
transfers pages from Xen hypervisor back to the
kernel based on different criteria.

topology= [S390]
Format: {off | on}
Specify if the kernel should make use of the cpu
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202 changes: 202 additions & 0 deletions Documentation/kernel-per-CPU-kthreads.txt
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REDUCING OS JITTER DUE TO PER-CPU KTHREADS

This document lists per-CPU kthreads in the Linux kernel and presents
options to control their OS jitter. Note that non-per-CPU kthreads are
not listed here. To reduce OS jitter from non-per-CPU kthreads, bind
them to a "housekeeping" CPU dedicated to such work.


REFERENCES

o Documentation/IRQ-affinity.txt: Binding interrupts to sets of CPUs.

o Documentation/cgroups: Using cgroups to bind tasks to sets of CPUs.

o man taskset: Using the taskset command to bind tasks to sets
of CPUs.

o man sched_setaffinity: Using the sched_setaffinity() system
call to bind tasks to sets of CPUs.

o /sys/devices/system/cpu/cpuN/online: Control CPU N's hotplug state,
writing "0" to offline and "1" to online.

o In order to locate kernel-generated OS jitter on CPU N:

cd /sys/kernel/debug/tracing
echo 1 > max_graph_depth # Increase the "1" for more detail
echo function_graph > current_tracer
# run workload
cat per_cpu/cpuN/trace


KTHREADS

Name: ehca_comp/%u
Purpose: Periodically process Infiniband-related work.
To reduce its OS jitter, do any of the following:
1. Don't use eHCA Infiniband hardware, instead choosing hardware
that does not require per-CPU kthreads. This will prevent these
kthreads from being created in the first place. (This will
work for most people, as this hardware, though important, is
relatively old and is produced in relatively low unit volumes.)
2. Do all eHCA-Infiniband-related work on other CPUs, including
interrupts.
3. Rework the eHCA driver so that its per-CPU kthreads are
provisioned only on selected CPUs.


Name: irq/%d-%s
Purpose: Handle threaded interrupts.
To reduce its OS jitter, do the following:
1. Use irq affinity to force the irq threads to execute on
some other CPU.

Name: kcmtpd_ctr_%d
Purpose: Handle Bluetooth work.
To reduce its OS jitter, do one of the following:
1. Don't use Bluetooth, in which case these kthreads won't be
created in the first place.
2. Use irq affinity to force Bluetooth-related interrupts to
occur on some other CPU and furthermore initiate all
Bluetooth activity on some other CPU.

Name: ksoftirqd/%u
Purpose: Execute softirq handlers when threaded or when under heavy load.
To reduce its OS jitter, each softirq vector must be handled
separately as follows:
TIMER_SOFTIRQ: Do all of the following:
1. To the extent possible, keep the CPU out of the kernel when it
is non-idle, for example, by avoiding system calls and by forcing
both kernel threads and interrupts to execute elsewhere.
2. Build with CONFIG_HOTPLUG_CPU=y. After boot completes, force
the CPU offline, then bring it back online. This forces
recurring timers to migrate elsewhere. If you are concerned
with multiple CPUs, force them all offline before bringing the
first one back online. Once you have onlined the CPUs in question,
do not offline any other CPUs, because doing so could force the
timer back onto one of the CPUs in question.
NET_TX_SOFTIRQ and NET_RX_SOFTIRQ: Do all of the following:
1. Force networking interrupts onto other CPUs.
2. Initiate any network I/O on other CPUs.
3. Once your application has started, prevent CPU-hotplug operations
from being initiated from tasks that might run on the CPU to
be de-jittered. (It is OK to force this CPU offline and then
bring it back online before you start your application.)
BLOCK_SOFTIRQ: Do all of the following:
1. Force block-device interrupts onto some other CPU.
2. Initiate any block I/O on other CPUs.
3. Once your application has started, prevent CPU-hotplug operations
from being initiated from tasks that might run on the CPU to
be de-jittered. (It is OK to force this CPU offline and then
bring it back online before you start your application.)
BLOCK_IOPOLL_SOFTIRQ: Do all of the following:
1. Force block-device interrupts onto some other CPU.
2. Initiate any block I/O and block-I/O polling on other CPUs.
3. Once your application has started, prevent CPU-hotplug operations
from being initiated from tasks that might run on the CPU to
be de-jittered. (It is OK to force this CPU offline and then
bring it back online before you start your application.)
TASKLET_SOFTIRQ: Do one or more of the following:
1. Avoid use of drivers that use tasklets. (Such drivers will contain
calls to things like tasklet_schedule().)
2. Convert all drivers that you must use from tasklets to workqueues.
3. Force interrupts for drivers using tasklets onto other CPUs,
and also do I/O involving these drivers on other CPUs.
SCHED_SOFTIRQ: Do all of the following:
1. Avoid sending scheduler IPIs to the CPU to be de-jittered,
for example, ensure that at most one runnable kthread is present
on that CPU. If a thread that expects to run on the de-jittered
CPU awakens, the scheduler will send an IPI that can result in
a subsequent SCHED_SOFTIRQ.
2. Build with CONFIG_RCU_NOCB_CPU=y, CONFIG_RCU_NOCB_CPU_ALL=y,
CONFIG_NO_HZ_FULL=y, and, in addition, ensure that the CPU
to be de-jittered is marked as an adaptive-ticks CPU using the
"nohz_full=" boot parameter. This reduces the number of
scheduler-clock interrupts that the de-jittered CPU receives,
minimizing its chances of being selected to do the load balancing
work that runs in SCHED_SOFTIRQ context.
3. To the extent possible, keep the CPU out of the kernel when it
is non-idle, for example, by avoiding system calls and by
forcing both kernel threads and interrupts to execute elsewhere.
This further reduces the number of scheduler-clock interrupts
received by the de-jittered CPU.
HRTIMER_SOFTIRQ: Do all of the following:
1. To the extent possible, keep the CPU out of the kernel when it
is non-idle. For example, avoid system calls and force both
kernel threads and interrupts to execute elsewhere.
2. Build with CONFIG_HOTPLUG_CPU=y. Once boot completes, force the
CPU offline, then bring it back online. This forces recurring
timers to migrate elsewhere. If you are concerned with multiple
CPUs, force them all offline before bringing the first one
back online. Once you have onlined the CPUs in question, do not
offline any other CPUs, because doing so could force the timer
back onto one of the CPUs in question.
RCU_SOFTIRQ: Do at least one of the following:
1. Offload callbacks and keep the CPU in either dyntick-idle or
adaptive-ticks state by doing all of the following:
a. Build with CONFIG_RCU_NOCB_CPU=y, CONFIG_RCU_NOCB_CPU_ALL=y,
CONFIG_NO_HZ_FULL=y, and, in addition ensure that the CPU
to be de-jittered is marked as an adaptive-ticks CPU using
the "nohz_full=" boot parameter. Bind the rcuo kthreads
to housekeeping CPUs, which can tolerate OS jitter.
b. To the extent possible, keep the CPU out of the kernel
when it is non-idle, for example, by avoiding system
calls and by forcing both kernel threads and interrupts
to execute elsewhere.
2. Enable RCU to do its processing remotely via dyntick-idle by
doing all of the following:
a. Build with CONFIG_NO_HZ=y and CONFIG_RCU_FAST_NO_HZ=y.
b. Ensure that the CPU goes idle frequently, allowing other
CPUs to detect that it has passed through an RCU quiescent
state. If the kernel is built with CONFIG_NO_HZ_FULL=y,
userspace execution also allows other CPUs to detect that
the CPU in question has passed through a quiescent state.
c. To the extent possible, keep the CPU out of the kernel
when it is non-idle, for example, by avoiding system
calls and by forcing both kernel threads and interrupts
to execute elsewhere.

Name: rcuc/%u
Purpose: Execute RCU callbacks in CONFIG_RCU_BOOST=y kernels.
To reduce its OS jitter, do at least one of the following:
1. Build the kernel with CONFIG_PREEMPT=n. This prevents these
kthreads from being created in the first place, and also obviates
the need for RCU priority boosting. This approach is feasible
for workloads that do not require high degrees of responsiveness.
2. Build the kernel with CONFIG_RCU_BOOST=n. This prevents these
kthreads from being created in the first place. This approach
is feasible only if your workload never requires RCU priority
boosting, for example, if you ensure frequent idle time on all
CPUs that might execute within the kernel.
3. Build with CONFIG_RCU_NOCB_CPU=y and CONFIG_RCU_NOCB_CPU_ALL=y,
which offloads all RCU callbacks to kthreads that can be moved
off of CPUs susceptible to OS jitter. This approach prevents the
rcuc/%u kthreads from having any work to do, so that they are
never awakened.
4. Ensure that the CPU never enters the kernel, and, in particular,
avoid initiating any CPU hotplug operations on this CPU. This is
another way of preventing any callbacks from being queued on the
CPU, again preventing the rcuc/%u kthreads from having any work
to do.

Name: rcuob/%d, rcuop/%d, and rcuos/%d
Purpose: Offload RCU callbacks from the corresponding CPU.
To reduce its OS jitter, do at least one of the following:
1. Use affinity, cgroups, or other mechanism to force these kthreads
to execute on some other CPU.
2. Build with CONFIG_RCU_NOCB_CPUS=n, which will prevent these
kthreads from being created in the first place. However, please
note that this will not eliminate OS jitter, but will instead
shift it to RCU_SOFTIRQ.

Name: watchdog/%u
Purpose: Detect software lockups on each CPU.
To reduce its OS jitter, do at least one of the following:
1. Build with CONFIG_LOCKUP_DETECTOR=n, which will prevent these
kthreads from being created in the first place.
2. Echo a zero to /proc/sys/kernel/watchdog to disable the
watchdog timer.
3. Echo a large number of /proc/sys/kernel/watchdog_thresh in
order to reduce the frequency of OS jitter due to the watchdog
timer down to a level that is acceptable for your workload.
15 changes: 8 additions & 7 deletions Documentation/power/devices.txt
Original file line number Diff line number Diff line change
Expand Up @@ -268,7 +268,7 @@ situations.
System Power Management Phases
------------------------------
Suspending or resuming the system is done in several phases. Different phases
are used for standby or memory sleep states ("suspend-to-RAM") and the
are used for freeze, standby, and memory sleep states ("suspend-to-RAM") and the
hibernation state ("suspend-to-disk"). Each phase involves executing callbacks
for every device before the next phase begins. Not all busses or classes
support all these callbacks and not all drivers use all the callbacks. The
Expand Down Expand Up @@ -309,7 +309,8 @@ execute the corresponding method from dev->driver->pm instead if there is one.

Entering System Suspend
-----------------------
When the system goes into the standby or memory sleep state, the phases are:
When the system goes into the freeze, standby or memory sleep state,
the phases are:

prepare, suspend, suspend_late, suspend_noirq.

Expand Down Expand Up @@ -368,7 +369,7 @@ the devices that were suspended.

Leaving System Suspend
----------------------
When resuming from standby or memory sleep, the phases are:
When resuming from freeze, standby or memory sleep, the phases are:

resume_noirq, resume_early, resume, complete.

Expand Down Expand Up @@ -433,8 +434,8 @@ the system log.

Entering Hibernation
--------------------
Hibernating the system is more complicated than putting it into the standby or
memory sleep state, because it involves creating and saving a system image.
Hibernating the system is more complicated than putting it into the other
sleep states, because it involves creating and saving a system image.
Therefore there are more phases for hibernation, with a different set of
callbacks. These phases always run after tasks have been frozen and memory has
been freed.
Expand Down Expand Up @@ -485,8 +486,8 @@ image forms an atomic snapshot of the system state.

At this point the system image is saved, and the devices then need to be
prepared for the upcoming system shutdown. This is much like suspending them
before putting the system into the standby or memory sleep state, and the phases
are similar.
before putting the system into the freeze, standby or memory sleep state,
and the phases are similar.

9. The prepare phase is discussed above.

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4 changes: 2 additions & 2 deletions Documentation/power/interface.txt
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Expand Up @@ -7,8 +7,8 @@ running. The interface exists in /sys/power/ directory (assuming sysfs
is mounted at /sys).

/sys/power/state controls system power state. Reading from this file
returns what states are supported, which is hard-coded to 'standby'
(Power-On Suspend), 'mem' (Suspend-to-RAM), and 'disk'
returns what states are supported, which is hard-coded to 'freeze',
'standby' (Power-On Suspend), 'mem' (Suspend-to-RAM), and 'disk'
(Suspend-to-Disk).

Writing to this file one of those strings causes the system to
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6 changes: 4 additions & 2 deletions Documentation/power/notifiers.txt
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Expand Up @@ -15,8 +15,10 @@ A suspend/hibernation notifier may be used for this purpose.
The subsystems or drivers having such needs can register suspend notifiers that
will be called upon the following events by the PM core:

PM_HIBERNATION_PREPARE The system is going to hibernate or suspend, tasks will
be frozen immediately.
PM_HIBERNATION_PREPARE The system is going to hibernate, tasks will be frozen
immediately. This is different from PM_SUSPEND_PREPARE
below because here we do additional work between notifiers
and drivers freezing.

PM_POST_HIBERNATION The system memory state has been restored from a
hibernation image or an error occurred during
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