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-rw-r--r--Documentation/admin-guide/bootconfig.rst2
-rw-r--r--Documentation/admin-guide/device-mapper/dm-init.rst8
-rw-r--r--Documentation/admin-guide/devices.txt5
-rw-r--r--Documentation/admin-guide/hw_random.rst6
-rw-r--r--Documentation/admin-guide/kernel-parameters.txt68
-rw-r--r--Documentation/admin-guide/media/cec-drivers.rst10
-rw-r--r--Documentation/admin-guide/media/cec.rst369
-rw-r--r--Documentation/admin-guide/media/index.rst3
-rw-r--r--Documentation/admin-guide/media/pulse8-cec.rst13
-rw-r--r--Documentation/admin-guide/media/v4l-drivers.rst1
-rw-r--r--Documentation/admin-guide/media/vimc.rst8
-rw-r--r--Documentation/admin-guide/media/visl.rst175
-rw-r--r--Documentation/admin-guide/media/vivid.rst2
-rw-r--r--Documentation/admin-guide/mm/zswap.rst8
-rw-r--r--Documentation/admin-guide/perf/hisi-pcie-pmu.rst112
-rw-r--r--Documentation/admin-guide/perf/index.rst2
-rw-r--r--Documentation/admin-guide/perf/meson-ddr-pmu.rst70
-rw-r--r--Documentation/admin-guide/perf/nvidia-pmu.rst299
-rw-r--r--Documentation/admin-guide/pm/amd-pstate.rst220
-rw-r--r--Documentation/admin-guide/sysctl/fs.rst240
-rw-r--r--Documentation/admin-guide/sysctl/kernel.rst26
21 files changed, 1359 insertions, 288 deletions
diff --git a/Documentation/admin-guide/bootconfig.rst b/Documentation/admin-guide/bootconfig.rst
index d99994345d41..9355c525fbe0 100644
--- a/Documentation/admin-guide/bootconfig.rst
+++ b/Documentation/admin-guide/bootconfig.rst
@@ -229,7 +229,7 @@ In addition to the kernel command line, the boot config can be used for
passing the kernel parameters. All the key-value pairs under ``kernel``
key will be passed to kernel cmdline directly. Moreover, the key-value
pairs under ``init`` will be passed to init process via the cmdline.
-The parameters are concatinated with user-given kernel cmdline string
+The parameters are concatenated with user-given kernel cmdline string
as the following order, so that the command line parameter can override
bootconfig parameters (this depends on how the subsystem handles parameters
but in general, earlier parameter will be overwritten by later one.)::
diff --git a/Documentation/admin-guide/device-mapper/dm-init.rst b/Documentation/admin-guide/device-mapper/dm-init.rst
index e5242ff17e9b..981d6a907699 100644
--- a/Documentation/admin-guide/device-mapper/dm-init.rst
+++ b/Documentation/admin-guide/device-mapper/dm-init.rst
@@ -123,3 +123,11 @@ Other examples (per target):
0 1638400 verity 1 8:1 8:2 4096 4096 204800 1 sha256
fb1a5a0f00deb908d8b53cb270858975e76cf64105d412ce764225d53b8f3cfd
51934789604d1b92399c52e7cb149d1b3a1b74bbbcb103b2a0aaacbed5c08584
+
+For setups using device-mapper on top of asynchronously probed block
+devices (MMC, USB, ..), it may be necessary to tell dm-init to
+explicitly wait for them to become available before setting up the
+device-mapper tables. This can be done with the "dm-mod.waitfor="
+module parameter, which takes a list of devices to wait for::
+
+ dm-mod.waitfor=<device1>[,..,<deviceN>]
diff --git a/Documentation/admin-guide/devices.txt b/Documentation/admin-guide/devices.txt
index 9764d6edb189..06c525e01ea5 100644
--- a/Documentation/admin-guide/devices.txt
+++ b/Documentation/admin-guide/devices.txt
@@ -3080,6 +3080,11 @@
...
255 = /dev/osd255 256th OSD Device
+ 261 char Compute Acceleration Devices
+ 0 = /dev/accel/accel0 First acceleration device
+ 1 = /dev/accel/accel1 Second acceleration device
+ ...
+
384-511 char RESERVED FOR DYNAMIC ASSIGNMENT
Character devices that request a dynamic allocation of major
number will take numbers starting from 511 and downward,
diff --git a/Documentation/admin-guide/hw_random.rst b/Documentation/admin-guide/hw_random.rst
index 121de96e395e..d494601717f1 100644
--- a/Documentation/admin-guide/hw_random.rst
+++ b/Documentation/admin-guide/hw_random.rst
@@ -1,6 +1,6 @@
-==========================================================
-Linux support for random number generator in i8xx chipsets
-==========================================================
+=================================
+Hardware random number generators
+=================================
Introduction
============
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index a465d5242774..fb388c6c8c60 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -703,6 +703,17 @@
condev= [HW,S390] console device
conmode=
+ con3215_drop= [S390] 3215 console drop mode.
+ Format: y|n|Y|N|1|0
+ When set to true, drop data on the 3215 console when
+ the console buffer is full. In this case the
+ operator using a 3270 terminal emulator (for example
+ x3270) does not have to enter the clear key for the
+ console output to advance and the kernel to continue.
+ This leads to a much faster boot time when a 3270
+ terminal emulator is active. If no 3270 terminal
+ emulator is used, this parameter has no effect.
+
console= [KNL] Output console device and options.
tty<n> Use the virtual console device <n>.
@@ -831,7 +842,7 @@
memory region [offset, offset + size] for that kernel
image. If '@offset' is omitted, then a suitable offset
is selected automatically.
- [KNL, X86-64] Select a region under 4G first, and
+ [KNL, X86-64, ARM64] Select a region under 4G first, and
fall back to reserve region above 4G when '@offset'
hasn't been specified.
See Documentation/admin-guide/kdump/kdump.rst for further details.
@@ -851,26 +862,23 @@
available.
It will be ignored if crashkernel=X is specified.
crashkernel=size[KMG],low
- [KNL, X86-64] range under 4G. When crashkernel=X,high
+ [KNL, X86-64, ARM64] range under 4G. When crashkernel=X,high
is passed, kernel could allocate physical memory region
above 4G, that cause second kernel crash on system
that require some amount of low memory, e.g. swiotlb
requires at least 64M+32K low memory, also enough extra
low memory is needed to make sure DMA buffers for 32-bit
devices won't run out. Kernel would try to allocate
- at least 256M below 4G automatically.
+ default size of memory below 4G automatically. The default
+ size is platform dependent.
+ --> x86: max(swiotlb_size_or_default() + 8MiB, 256MiB)
+ --> arm64: 128MiB
This one lets the user specify own low range under 4G
for second kernel instead.
0: to disable low allocation.
It will be ignored when crashkernel=X,high is not used
or memory reserved is below 4G.
- [KNL, ARM64] range in low memory.
- This one lets the user specify a low range in the
- DMA zone for the crash dump kernel.
- It will be ignored when crashkernel=X,high is not used
- or memory reserved is located in the DMA zones.
-
cryptomgr.notests
[KNL] Disable crypto self-tests
@@ -3777,12 +3785,15 @@
shutdown the other cpus. Instead use the REBOOT_VECTOR
irq.
- nomodeset Disable kernel modesetting. DRM drivers will not perform
- display-mode changes or accelerated rendering. Only the
- system framebuffer will be available for use if this was
- set-up by the firmware or boot loader.
+ nomodeset Disable kernel modesetting. Most systems' firmware
+ sets up a display mode and provides framebuffer memory
+ for output. With nomodeset, DRM and fbdev drivers will
+ not load if they could possibly displace the pre-
+ initialized output. Only the system framebuffer will
+ be available for use. The respective drivers will not
+ perform display-mode changes or accelerated rendering.
- Useful as fallback, or for testing and debugging.
+ Useful as error fallback, or for testing and debugging.
nomodule Disable module load
@@ -4566,17 +4577,15 @@
ramdisk_start= [RAM] RAM disk image start address
- random.trust_cpu={on,off}
- [KNL] Enable or disable trusting the use of the
- CPU's random number generator (if available) to
- fully seed the kernel's CRNG. Default is controlled
- by CONFIG_RANDOM_TRUST_CPU.
+ random.trust_cpu=off
+ [KNL] Disable trusting the use of the CPU's
+ random number generator (if available) to
+ initialize the kernel's RNG.
- random.trust_bootloader={on,off}
- [KNL] Enable or disable trusting the use of a
- seed passed by the bootloader (if available) to
- fully seed the kernel's CRNG. Default is controlled
- by CONFIG_RANDOM_TRUST_BOOTLOADER.
+ random.trust_bootloader=off
+ [KNL] Disable trusting the use of the a seed
+ passed by the bootloader (if available) to
+ initialize the kernel's RNG.
randomize_kstack_offset=
[KNL] Enable or disable kernel stack offset
@@ -6959,3 +6968,14 @@
memory, and other data can't be written using
xmon commands.
off xmon is disabled.
+
+ amd_pstate= [X86]
+ disable
+ Do not enable amd_pstate as the default
+ scaling driver for the supported processors
+ passive
+ Use amd_pstate as a scaling driver, driver requests a
+ desired performance on this abstract scale and the power
+ management firmware translates the requests into actual
+ hardware states (core frequency, data fabric and memory
+ clocks etc.)
diff --git a/Documentation/admin-guide/media/cec-drivers.rst b/Documentation/admin-guide/media/cec-drivers.rst
deleted file mode 100644
index 8d9686c08df9..000000000000
--- a/Documentation/admin-guide/media/cec-drivers.rst
+++ /dev/null
@@ -1,10 +0,0 @@
-.. SPDX-License-Identifier: GPL-2.0
-
-=================================
-CEC driver-specific documentation
-=================================
-
-.. toctree::
- :maxdepth: 2
-
- pulse8-cec
diff --git a/Documentation/admin-guide/media/cec.rst b/Documentation/admin-guide/media/cec.rst
new file mode 100644
index 000000000000..5c7259371494
--- /dev/null
+++ b/Documentation/admin-guide/media/cec.rst
@@ -0,0 +1,369 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+========
+HDMI CEC
+========
+
+Supported hardware in mainline
+==============================
+
+HDMI Transmitters:
+
+- Exynos4
+- Exynos5
+- STIH4xx HDMI CEC
+- V4L2 adv7511 (same HW, but a different driver from the drm adv7511)
+- stm32
+- Allwinner A10 (sun4i)
+- Raspberry Pi
+- dw-hdmi (Synopsis IP)
+- amlogic (meson ao-cec and ao-cec-g12a)
+- drm adv7511/adv7533
+- omap4
+- tegra
+- rk3288, rk3399
+- tda998x
+- DisplayPort CEC-Tunneling-over-AUX on i915, nouveau and amdgpu
+- ChromeOS EC CEC
+- CEC for SECO boards (UDOO x86).
+- Chrontel CH7322
+
+
+HDMI Receivers:
+
+- adv7604/11/12
+- adv7842
+- tc358743
+
+USB Dongles (see below for additional information on how to use these
+dongles):
+
+- Pulse-Eight: the pulse8-cec driver implements the following module option:
+ ``persistent_config``: by default this is off, but when set to 1 the driver
+ will store the current settings to the device's internal eeprom and restore
+ it the next time the device is connected to the USB port.
+- RainShadow Tech. Note: this driver does not support the persistent_config
+ module option of the Pulse-Eight driver. The hardware supports it, but I
+ have no plans to add this feature. But I accept patches :-)
+
+Miscellaneous:
+
+- vivid: emulates a CEC receiver and CEC transmitter.
+ Can be used to test CEC applications without actual CEC hardware.
+
+- cec-gpio. If the CEC pin is hooked up to a GPIO pin then
+ you can control the CEC line through this driver. This supports error
+ injection as well.
+
+
+Utilities
+=========
+
+Utilities are available here: https://git.linuxtv.org/v4l-utils.git
+
+``utils/cec-ctl``: control a CEC device
+
+``utils/cec-compliance``: test compliance of a remote CEC device
+
+``utils/cec-follower``: emulate a CEC follower device
+
+Note that ``cec-ctl`` has support for the CEC Hospitality Profile as is
+used in some hotel displays. See http://www.htng.org.
+
+Note that the libcec library (https://github.com/Pulse-Eight/libcec) supports
+the linux CEC framework.
+
+If you want to get the CEC specification, then look at the References of
+the HDMI wikipedia page: https://en.wikipedia.org/wiki/HDMI. CEC is part
+of the HDMI specification. HDMI 1.3 is freely available (very similar to
+HDMI 1.4 w.r.t. CEC) and should be good enough for most things.
+
+
+DisplayPort to HDMI Adapters with working CEC
+=============================================
+
+Background: most adapters do not support the CEC Tunneling feature,
+and of those that do many did not actually connect the CEC pin.
+Unfortunately, this means that while a CEC device is created, it
+is actually all alone in the world and will never be able to see other
+CEC devices.
+
+This is a list of known working adapters that have CEC Tunneling AND
+that properly connected the CEC pin. If you find adapters that work
+but are not in this list, then drop me a note.
+
+To test: hook up your DP-to-HDMI adapter to a CEC capable device
+(typically a TV), then run::
+
+ cec-ctl --playback # Configure the PC as a CEC Playback device
+ cec-ctl -S # Show the CEC topology
+
+The ``cec-ctl -S`` command should show at least two CEC devices,
+ourselves and the CEC device you are connected to (i.e. typically the TV).
+
+General note: I have only seen this work with the Parade PS175, PS176 and
+PS186 chipsets and the MegaChips 2900. While MegaChips 28x0 claims CEC support,
+I have never seen it work.
+
+USB-C to HDMI
+-------------
+
+Samsung Multiport Adapter EE-PW700: https://www.samsung.com/ie/support/model/EE-PW700BBEGWW/
+
+Kramer ADC-U31C/HF: https://www.kramerav.com/product/ADC-U31C/HF
+
+Club3D CAC-2504: https://www.club-3d.com/en/detail/2449/usb_3.1_type_c_to_hdmi_2.0_uhd_4k_60hz_active_adapter/
+
+DisplayPort to HDMI
+-------------------
+
+Club3D CAC-1080: https://www.club-3d.com/en/detail/2442/displayport_1.4_to_hdmi_2.0b_hdr/
+
+CableCreation (SKU: CD0712): https://www.cablecreation.com/products/active-displayport-to-hdmi-adapter-4k-hdr
+
+HP DisplayPort to HDMI True 4k Adapter (P/N 2JA63AA): https://www.hp.com/us-en/shop/pdp/hp-displayport-to-hdmi-true-4k-adapter
+
+Mini-DisplayPort to HDMI
+------------------------
+
+Club3D CAC-1180: https://www.club-3d.com/en/detail/2443/mini_displayport_1.4_to_hdmi_2.0b_hdr/
+
+Note that passive adapters will never work, you need an active adapter.
+
+The Club3D adapters in this list are all MegaChips 2900 based. Other Club3D adapters
+are PS176 based and do NOT have the CEC pin hooked up, so only the three Club3D
+adapters above are known to work.
+
+I suspect that MegaChips 2900 based designs in general are likely to work
+whereas with the PS176 it is more hit-and-miss (mostly miss). The PS186 is
+likely to have the CEC pin hooked up, it looks like they changed the reference
+design for that chipset.
+
+
+USB CEC Dongles
+===============
+
+These dongles appear as ``/dev/ttyACMX`` devices and need the ``inputattach``
+utility to create the ``/dev/cecX`` devices. Support for the Pulse-Eight
+has been added to ``inputattach`` 1.6.0. Support for the Rainshadow Tech has
+been added to ``inputattach`` 1.6.1.
+
+You also need udev rules to automatically start systemd services::
+
+ SUBSYSTEM=="tty", KERNEL=="ttyACM[0-9]*", ATTRS{idVendor}=="2548", ATTRS{idProduct}=="1002", ACTION=="add", TAG+="systemd", ENV{SYSTEMD_WANTS}+="pulse8-cec-inputattach@%k.service"
+ SUBSYSTEM=="tty", KERNEL=="ttyACM[0-9]*", ATTRS{idVendor}=="2548", ATTRS{idProduct}=="1001", ACTION=="add", TAG+="systemd", ENV{SYSTEMD_WANTS}+="pulse8-cec-inputattach@%k.service"
+ SUBSYSTEM=="tty", KERNEL=="ttyACM[0-9]*", ATTRS{idVendor}=="04d8", ATTRS{idProduct}=="ff59", ACTION=="add", TAG+="systemd", ENV{SYSTEMD_WANTS}+="rainshadow-cec-inputattach@%k.service"
+
+and these systemd services:
+
+For Pulse-Eight make /lib/systemd/system/pulse8-cec-inputattach@.service::
+
+ [Unit]
+ Description=inputattach for pulse8-cec device on %I
+
+ [Service]
+ Type=simple
+ ExecStart=/usr/bin/inputattach --pulse8-cec /dev/%I
+
+For the RainShadow Tech make /lib/systemd/system/rainshadow-cec-inputattach@.service::
+
+ [Unit]
+ Description=inputattach for rainshadow-cec device on %I
+
+ [Service]
+ Type=simple
+ ExecStart=/usr/bin/inputattach --rainshadow-cec /dev/%I
+
+
+For proper suspend/resume support create: /lib/systemd/system/restart-cec-inputattach.service::
+
+ [Unit]
+ Description=restart inputattach for cec devices
+ After=suspend.target
+
+ [Service]
+ Type=forking
+ ExecStart=/bin/bash -c 'for d in /dev/serial/by-id/usb-Pulse-Eight*; do /usr/bin/inputattach --daemon --pulse8-cec $d; done; for d in /dev/serial/by-id/usb-RainShadow_Tech*; do /usr/bin/inputattach --daemon --rainshadow-cec $d; done'
+
+ [Install]
+ WantedBy=suspend.target
+
+And run ``systemctl enable restart-cec-inputattach``.
+
+To automatically set the physical address of the CEC device whenever the
+EDID changes, you can use ``cec-ctl`` with the ``-E`` option::
+
+ cec-ctl -E /sys/class/drm/card0-DP-1/edid
+
+This assumes the dongle is connected to the card0-DP-1 output (``xrandr`` will tell
+you which output is used) and it will poll for changes to the EDID and update
+the Physical Address whenever they occur.
+
+To automatically run this command you can use cron. Edit crontab with
+``crontab -e`` and add this line::
+
+ @reboot /usr/local/bin/cec-ctl -E /sys/class/drm/card0-DP-1/edid
+
+This only works for display drivers that expose the EDID in ``/sys/class/drm``,
+such as the i915 driver.
+
+
+CEC Without HPD
+===============
+
+Some displays when in standby mode have no HDMI Hotplug Detect signal, but
+CEC is still enabled so connected devices can send an <Image View On> CEC
+message in order to wake up such displays. Unfortunately, not all CEC
+adapters can support this. An example is the Odroid-U3 SBC that has a
+level-shifter that is powered off when the HPD signal is low, thus
+blocking the CEC pin. Even though the SoC can use CEC without a HPD,
+the level-shifter will prevent this from functioning.
+
+There is a CEC capability flag to signal this: ``CEC_CAP_NEEDS_HPD``.
+If set, then the hardware cannot wake up displays with this behavior.
+
+Note for CEC application implementers: the <Image View On> message must
+be the first message you send, don't send any other messages before.
+Certain very bad but unfortunately not uncommon CEC implementations
+get very confused if they receive anything else but this message and
+they won't wake up.
+
+When writing a driver it can be tricky to test this. There are two
+ways to do this:
+
+1) Get a Pulse-Eight USB CEC dongle, connect an HDMI cable from your
+ device to the Pulse-Eight, but do not connect the Pulse-Eight to
+ the display.
+
+ Now configure the Pulse-Eight dongle::
+
+ cec-ctl -p0.0.0.0 --tv
+
+ and start monitoring::
+
+ sudo cec-ctl -M
+
+ On the device you are testing run::
+
+ cec-ctl --playback
+
+ It should report a physical address of f.f.f.f. Now run this
+ command::
+
+ cec-ctl -t0 --image-view-on
+
+ The Pulse-Eight should see the <Image View On> message. If not,
+ then something (hardware and/or software) is preventing the CEC
+ message from going out.
+
+ To make sure you have the wiring correct just connect the
+ Pulse-Eight to a CEC-enabled display and run the same command
+ on your device: now there is a HPD, so you should see the command
+ arriving at the Pulse-Eight.
+
+2) If you have another linux device supporting CEC without HPD, then
+ you can just connect your device to that device. Yes, you can connect
+ two HDMI outputs together. You won't have a HPD (which is what we
+ want for this test), but the second device can monitor the CEC pin.
+
+ Otherwise use the same commands as in 1.
+
+If CEC messages do not come through when there is no HPD, then you
+need to figure out why. Typically it is either a hardware restriction
+or the software powers off the CEC core when the HPD goes low. The
+first cannot be corrected of course, the second will likely required
+driver changes.
+
+
+Microcontrollers & CEC
+======================
+
+We have seen some CEC implementations in displays that use a microcontroller
+to sample the bus. This does not have to be a problem, but some implementations
+have timing issues. This is hard to discover unless you can hook up a low-level
+CEC debugger (see the next section).
+
+You will see cases where the CEC transmitter holds the CEC line high or low for
+a longer time than is allowed. For directed messages this is not a problem since
+if that happens the message will not be Acked and it will be retransmitted.
+For broadcast messages no such mechanism exists.
+
+It's not clear what to do about this. It is probably wise to transmit some
+broadcast messages twice to reduce the chance of them being lost. Specifically
+<Standby> and <Active Source> are candidates for that.
+
+
+Making a CEC debugger
+=====================
+
+By using a Raspberry Pi 2B/3/4 and some cheap components you can make
+your own low-level CEC debugger.
+
+Here is a picture of my setup:
+
+https://hverkuil.home.xs4all.nl/rpi3-cec.jpg
+
+It's a Raspberry Pi 3 together with a breadboard and some breadboard wires:
+
+http://www.dx.com/p/diy-40p-male-to-female-male-to-male-female-to-female-dupont-line-wire-3pcs-356089#.WYLOOXWGN7I
+
+Finally on of these HDMI female-female passthrough connectors (full soldering type 1):
+
+https://elabbay.myshopify.com/collections/camera/products/hdmi-af-af-v1a-hdmi-type-a-female-to-hdmi-type-a-female-pass-through-adapter-breakout-board?variant=45533926147
+
+We've tested this and it works up to 4kp30 (297 MHz). The quality is not high
+enough to pass-through 4kp60 (594 MHz).
+
+I also added an RTC and a breakout shield:
+
+https://www.amazon.com/Makerfire%C2%AE-Raspberry-Module-DS1307-Battery/dp/B00ZOXWHK4
+
+https://www.dx.com/p/raspberry-pi-gpio-expansion-board-breadboard-easy-multiplexing-board-one-to-three-with-screw-for-raspberry-pi-2-3-b-b-2729992.html#.YGRCG0MzZ7I
+
+These two are not needed but they make life a bit easier.
+
+If you want to monitor the HPD line as well, then you need one of these
+level shifters:
+
+https://www.adafruit.com/product/757
+
+(This is just where I got these components, there are many other places you
+can get similar things).
+
+The CEC pin of the HDMI connector needs to be connected to these pins:
+CE0/IO8 and CE1/IO7 (pull-up GPIOs). The (optional) HPD pin of the HDMI
+connector should be connected (via a level shifter to convert the 5V
+to 3.3V) to these pins: IO17 and IO27. The (optional) 5V pin of the HDMI
+connector should be connected (via a level shifter) to these pins: IO22
+and IO24. Monitoring the HPD an 5V lines is not necessary, but it is helpful.
+
+This kernel patch will hook up the cec-gpio driver correctly to
+e.g. ``arch/arm/boot/dts/bcm2837-rpi-3-b-plus.dts``::
+
+ cec-gpio@7 {
+ compatible = "cec-gpio";
+ cec-gpios = <&gpio 7 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>;
+ hpd-gpios = <&gpio 17 GPIO_ACTIVE_HIGH>;
+ v5-gpios = <&gpio 22 GPIO_ACTIVE_HIGH>;
+ };
+
+ cec-gpio@8 {
+ compatible = "cec-gpio";
+ cec-gpios = <&gpio 8 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>;
+ hpd-gpios = <&gpio 27 GPIO_ACTIVE_HIGH>;
+ v5-gpios = <&gpio 24 GPIO_ACTIVE_HIGH>;
+ };
+
+This dts change will enable two cec GPIO devices: I typically use one to
+send/receive CEC commands and the other to monitor. If you monitor using
+an unconfigured CEC adapter then it will use GPIO interrupts which makes
+monitoring very accurate.
+
+The documentation on how to use the error injection is here: :ref:`cec_pin_error_inj`.
+
+``cec-ctl --monitor-pin`` will do low-level CEC bus sniffing and analysis.
+You can also store the CEC traffic to file using ``--store-pin`` and analyze
+it later using ``--analyze-pin``.
+
+You can also use this as a full-fledged CEC device by configuring it
+using ``cec-ctl --tv -p0.0.0.0`` or ``cec-ctl --playback -p1.0.0.0``.
diff --git a/Documentation/admin-guide/media/index.rst b/Documentation/admin-guide/media/index.rst
index c676af665111..43f4a292b245 100644
--- a/Documentation/admin-guide/media/index.rst
+++ b/Documentation/admin-guide/media/index.rst
@@ -38,13 +38,14 @@ The media subsystem
remote-controller
+ cec
+
dvb
cardlist
v4l-drivers
dvb-drivers
- cec-drivers
**Copyright** |copy| 1999-2020 : LinuxTV Developers
diff --git a/Documentation/admin-guide/media/pulse8-cec.rst b/Documentation/admin-guide/media/pulse8-cec.rst
deleted file mode 100644
index 356d08b519f3..000000000000
--- a/Documentation/admin-guide/media/pulse8-cec.rst
+++ /dev/null
@@ -1,13 +0,0 @@
-.. SPDX-License-Identifier: GPL-2.0
-
-Pulse-Eight CEC Adapter driver
-==============================
-
-The pulse8-cec driver implements the following module option:
-
-``persistent_config``
----------------------
-
-By default this is off, but when set to 1 the driver will store the current
-settings to the device's internal eeprom and restore it the next time the
-device is connected to the USB port.
diff --git a/Documentation/admin-guide/media/v4l-drivers.rst b/Documentation/admin-guide/media/v4l-drivers.rst
index 9c7ebe2ca3bd..90a026ee05c6 100644
--- a/Documentation/admin-guide/media/v4l-drivers.rst
+++ b/Documentation/admin-guide/media/v4l-drivers.rst
@@ -31,4 +31,5 @@ Video4Linux (V4L) driver-specific documentation
si4713
si476x
vimc
+ visl
vivid
diff --git a/Documentation/admin-guide/media/vimc.rst b/Documentation/admin-guide/media/vimc.rst
index 3b4d2b36b4f3..29d843a8ddb1 100644
--- a/Documentation/admin-guide/media/vimc.rst
+++ b/Documentation/admin-guide/media/vimc.rst
@@ -35,11 +35,11 @@ of commands fits for the default topology:
media-ctl -d platform:vimc -V '"Sensor A":0[fmt:SBGGR8_1X8/640x480]'
media-ctl -d platform:vimc -V '"Debayer A":0[fmt:SBGGR8_1X8/640x480]'
- media-ctl -d platform:vimc -V '"Sensor B":0[fmt:SBGGR8_1X8/640x480]'
- media-ctl -d platform:vimc -V '"Debayer B":0[fmt:SBGGR8_1X8/640x480]'
- v4l2-ctl -z platform:vimc -d "RGB/YUV Capture" -v width=1920,height=1440
+ media-ctl -d platform:vimc -V '"Scaler":0[fmt:RGB888_1X24/640x480]'
+ media-ctl -d platform:vimc -V '"Scaler":0[crop:(100,50)/400x150]'
+ media-ctl -d platform:vimc -V '"Scaler":1[fmt:RGB888_1X24/300x700]'
+ v4l2-ctl -z platform:vimc -d "RGB/YUV Capture" -v width=300,height=700
v4l2-ctl -z platform:vimc -d "Raw Capture 0" -v pixelformat=BA81
- v4l2-ctl -z platform:vimc -d "Raw Capture 1" -v pixelformat=BA81
Subdevices
----------
diff --git a/Documentation/admin-guide/media/visl.rst b/Documentation/admin-guide/media/visl.rst
new file mode 100644
index 000000000000..7d2dc78341c9
--- /dev/null
+++ b/Documentation/admin-guide/media/visl.rst
@@ -0,0 +1,175 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+The Virtual Stateless Decoder Driver (visl)
+===========================================
+
+A virtual stateless decoder device for stateless uAPI development
+purposes.
+
+This tool's objective is to help the development and testing of
+userspace applications that use the V4L2 stateless API to decode media.
+
+A userspace implementation can use visl to run a decoding loop even when
+no hardware is available or when the kernel uAPI for the codec has not
+been upstreamed yet. This can reveal bugs at an early stage.
+
+This driver can also trace the contents of the V4L2 controls submitted
+to it. It can also dump the contents of the vb2 buffers through a
+debugfs interface. This is in many ways similar to the tracing
+infrastructure available for other popular encode/decode APIs out there
+and can help develop a userspace application by using another (working)
+one as a reference.
+
+.. note::
+
+ No actual decoding of video frames is performed by visl. The
+ V4L2 test pattern generator is used to write various debug information
+ to the capture buffers instead.
+
+Module parameters
+-----------------
+
+- visl_debug: Activates debug info, printing various debug messages through
+ dprintk. Also controls whether per-frame debug info is shown. Defaults to off.
+ Note that enabling this feature can result in slow performance through serial.
+
+- visl_transtime_ms: Simulated process time in milliseconds. Slowing down the
+ decoding speed can be useful for debugging.
+
+- visl_dprintk_frame_start, visl_dprintk_frame_nframes: Dictates a range of
+ frames where dprintk is activated. This only controls the dprintk tracing on a
+ per-frame basis. Note that printing a lot of data can be slow through serial.
+
+- keep_bitstream_buffers: Controls whether bitstream (i.e. OUTPUT) buffers are
+ kept after a decoding session. Defaults to false so as to reduce the amount of
+ clutter. keep_bitstream_buffers == false works well when live debugging the
+ client program with GDB.
+
+- bitstream_trace_frame_start, bitstream_trace_nframes: Similar to
+ visl_dprintk_frame_start, visl_dprintk_nframes, but controls the dumping of
+ buffer data through debugfs instead.
+
+What is the default use case for this driver?
+---------------------------------------------
+
+This driver can be used as a way to compare different userspace implementations.
+This assumes that a working client is run against visl and that the ftrace and
+OUTPUT buffer data is subsequently used to debug a work-in-progress
+implementation.
+
+Information on reference frames, their timestamps, the status of the OUTPUT and
+CAPTURE queues and more can be read directly from the CAPTURE buffers.
+
+Supported codecs
+----------------
+
+The following codecs are supported:
+
+- FWHT
+- MPEG2
+- VP8
+- VP9
+- H.264
+- HEVC
+
+visl trace events
+-----------------
+The trace events are defined on a per-codec basis, e.g.:
+
+.. code-block:: bash
+
+ $ ls /sys/kernel/debug/tracing/events/ | grep visl
+ visl_fwht_controls
+ visl_h264_controls
+ visl_hevc_controls
+ visl_mpeg2_controls
+ visl_vp8_controls
+ visl_vp9_controls
+
+For example, in order to dump HEVC SPS data:
+
+.. code-block:: bash
+
+ $ echo 1 > /sys/kernel/debug/tracing/events/visl_hevc_controls/v4l2_ctrl_hevc_sps/enable
+
+The SPS data will be dumped to the trace buffer, i.e.:
+
+.. code-block:: bash
+
+ $ cat /sys/kernel/debug/tracing/trace
+ video_parameter_set_id 0
+ seq_parameter_set_id 0
+ pic_width_in_luma_samples 1920
+ pic_height_in_luma_samples 1080
+ bit_depth_luma_minus8 0
+ bit_depth_chroma_minus8 0
+ log2_max_pic_order_cnt_lsb_minus4 4
+ sps_max_dec_pic_buffering_minus1 6
+ sps_max_num_reorder_pics 2
+ sps_max_latency_increase_plus1 0
+ log2_min_luma_coding_block_size_minus3 0
+ log2_diff_max_min_luma_coding_block_size 3
+ log2_min_luma_transform_block_size_minus2 0
+ log2_diff_max_min_luma_transform_block_size 3
+ max_transform_hierarchy_depth_inter 2
+ max_transform_hierarchy_depth_intra 2
+ pcm_sample_bit_depth_luma_minus1 0
+ pcm_sample_bit_depth_chroma_minus1 0
+ log2_min_pcm_luma_coding_block_size_minus3 0
+ log2_diff_max_min_pcm_luma_coding_block_size 0
+ num_short_term_ref_pic_sets 0
+ num_long_term_ref_pics_sps 0
+ chroma_format_idc 1
+ sps_max_sub_layers_minus1 0
+ flags AMP_ENABLED|SAMPLE_ADAPTIVE_OFFSET|TEMPORAL_MVP_ENABLED|STRONG_INTRA_SMOOTHING_ENABLED
+
+
+Dumping OUTPUT buffer data through debugfs
+------------------------------------------
+
+If the **VISL_DEBUGFS** Kconfig is enabled, visl will populate
+**/sys/kernel/debug/visl/bitstream** with OUTPUT buffer data according to the
+values of bitstream_trace_frame_start and bitstream_trace_nframes. This can
+highlight errors as broken clients may fail to fill the buffers properly.
+
+A single file is created for each processed OUTPUT buffer. Its name contains an
+integer that denotes the buffer sequence, i.e.:
+
+.. code-block:: c
+
+ snprintf(name, 32, "bitstream%d", run->src->sequence);
+
+Dumping the values is simply a matter of reading from the file, i.e.:
+
+For the buffer with sequence == 0:
+
+.. code-block:: bash
+
+ $ xxd /sys/kernel/debug/visl/bitstream/bitstream0
+ 00000000: 2601 af04 d088 bc25 a173 0e41 a4f2 3274 &......%.s.A..2t
+ 00000010: c668 cb28 e775 b4ac f53a ba60 f8fd 3aa1 .h.(.u...:.`..:.
+ 00000020: 46b4 bcfc 506c e227 2372 e5f5 d7ea 579f F...Pl.'#r....W.
+ 00000030: 6371 5eb5 0eb8 23b5 ca6a 5de5 983a 19e4 cq^...#..j]..:..
+ 00000040: e8c3 4320 b4ba a226 cbc1 4138 3a12 32d6 ..C ...&..A8:.2.
+ 00000050: fef3 247b 3523 4e90 9682 ac8e eb0c a389 ..${5#N.........
+ 00000060: ddd0 6cfc 0187 0e20 7aae b15b 1812 3d33 ..l.... z..[..=3
+ 00000070: e1c5 f425 a83a 00b7 4f18 8127 3c4c aefb ...%.:..O..'<L..
+
+For the buffer with sequence == 1:
+
+.. code-block:: bash
+
+ $ xxd /sys/kernel/debug/visl/bitstream/bitstream1
+ 00000000: 0201 d021 49e1 0c40 aa11 1449 14a6 01dc ...!I..@...I....
+ 00000010: 7023 889a c8cd 2cd0 13b4 dab0 e8ca 21fe p#....,.......!.
+ 00000020: c4c8 ab4c 486e 4e2f b0df 96cc c74e 8dde ...LHnN/.....N..
+ 00000030: 8ce7 ee36 d880 4095 4d64 30a0 ff4f 0c5e ...6..@.Md0..O.^
+ 00000040: f16b a6a1 d806 ca2a 0ece a673 7bea 1f37 .k.....*...s{..7
+ 00000050: 370f 5bb9 1dc4 ba21 6434 bc53 0173 cba0 7.[....!d4.S.s..
+ 00000060: dfe6 bc99 01ea b6e0 346b 92b5 c8de 9f5d ........4k.....]
+ 00000070: e7cc 3484 1769 fef2 a693 a945 2c8b 31da ..4..i.....E,.1.
+
+And so on.
+
+By default, the files are removed during STREAMOFF. This is to reduce the amount
+of clutter.
diff --git a/Documentation/admin-guide/media/vivid.rst b/Documentation/admin-guide/media/vivid.rst
index abd90ed31090..672a8371f6ad 100644
--- a/Documentation/admin-guide/media/vivid.rst
+++ b/Documentation/admin-guide/media/vivid.rst
@@ -392,7 +392,7 @@ Which one is returned depends on the chosen channel, each next valid channel
will cycle through the possible audio subchannel combinations. This allows
you to test the various combinations by just switching channels..
-Finally, for these inputs the v4l2_timecode struct is filled in in the
+Finally, for these inputs the v4l2_timecode struct is filled in the
dequeued v4l2_buffer struct.
diff --git a/Documentation/admin-guide/mm/zswap.rst b/Documentation/admin-guide/mm/zswap.rst
index 6e6f7b0d6562..f67de481c7f6 100644
--- a/Documentation/admin-guide/mm/zswap.rst
+++ b/Documentation/admin-guide/mm/zswap.rst
@@ -14,13 +14,7 @@ for potentially reduced swap I/O. This trade-off can also result in a
significant performance improvement if reads from the compressed cache are
faster than reads from a swap device.
-.. note::
- Zswap is a new feature as of v3.11 and interacts heavily with memory
- reclaim. This interaction has not been fully explored on the large set of
- potential configurations and workloads that exist. For this reason, zswap
- is a work in progress and should be considered experimental.
-
- Some potential benefits:
+Some potential benefits:
* Desktop/laptop users with limited RAM capacities can mitigate the
performance impact of swapping.
diff --git a/Documentation/admin-guide/perf/hisi-pcie-pmu.rst b/Documentation/admin-guide/perf/hisi-pcie-pmu.rst
index 294ebbdb22af..7e863662e2d4 100644
--- a/Documentation/admin-guide/perf/hisi-pcie-pmu.rst
+++ b/Documentation/admin-guide/perf/hisi-pcie-pmu.rst
@@ -15,10 +15,10 @@ HiSilicon PCIe PMU driver
The PCIe PMU driver registers a perf PMU with the name of its sicl-id and PCIe
Core id.::
- /sys/bus/event_source/hisi_pcie<sicl>_<core>
+ /sys/bus/event_source/hisi_pcie<sicl>_core<core>
PMU driver provides description of available events and filter options in sysfs,
-see /sys/bus/event_source/devices/hisi_pcie<sicl>_<core>.
+see /sys/bus/event_source/devices/hisi_pcie<sicl>_core<core>.
The "format" directory describes all formats of the config (events) and config1
(filter options) fields of the perf_event_attr structure. The "events" directory
@@ -33,13 +33,13 @@ monitored by PMU.
Example usage of perf::
$# perf list
- hisi_pcie0_0/rx_mwr_latency/ [kernel PMU event]
- hisi_pcie0_0/rx_mwr_cnt/ [kernel PMU event]
+ hisi_pcie0_core0/rx_mwr_latency/ [kernel PMU event]
+ hisi_pcie0_core0/rx_mwr_cnt/ [kernel PMU event]
------------------------------------------
- $# perf stat -e hisi_pcie0_0/rx_mwr_latency/
- $# perf stat -e hisi_pcie0_0/rx_mwr_cnt/
- $# perf stat -g -e hisi_pcie0_0/rx_mwr_latency/ -e hisi_pcie0_0/rx_mwr_cnt/
+ $# perf stat -e hisi_pcie0_core0/rx_mwr_latency/
+ $# perf stat -e hisi_pcie0_core0/rx_mwr_cnt/
+ $# perf stat -g -e hisi_pcie0_core0/rx_mwr_latency/ -e hisi_pcie0_core0/rx_mwr_cnt/
The current driver does not support sampling. So "perf record" is unsupported.
Also attach to a task is unsupported for PCIe PMU.
@@ -48,59 +48,83 @@ Filter options
--------------
1. Target filter
-PMU could only monitor the performance of traffic downstream target Root Ports
-or downstream target Endpoint. PCIe PMU driver support "port" and "bdf"
-interfaces for users, and these two interfaces aren't supported at the same
-time.
--port
-"port" filter can be used in all PCIe PMU events, target Root Port can be
-selected by configuring the 16-bits-bitmap "port". Multi ports can be selected
-for AP-layer-events, and only one port can be selected for TL/DL-layer-events.
+ PMU could only monitor the performance of traffic downstream target Root
+ Ports or downstream target Endpoint. PCIe PMU driver support "port" and
+ "bdf" interfaces for users, and these two interfaces aren't supported at the
+ same time.
-For example, if target Root Port is 0000:00:00.0 (x8 lanes), bit0 of bitmap
-should be set, port=0x1; if target Root Port is 0000:00:04.0 (x4 lanes),
-bit8 is set, port=0x100; if these two Root Ports are both monitored, port=0x101.
+ - port
-Example usage of perf::
+ "port" filter can be used in all PCIe PMU events, target Root Port can be
+ selected by configuring the 16-bits-bitmap "port". Multi ports can be
+ selected for AP-layer-events, and only one port can be selected for
+ TL/DL-layer-events.
- $# perf stat -e hisi_pcie0_0/rx_mwr_latency,port=0x1/ sleep 5
+ For example, if target Root Port is 0000:00:00.0 (x8 lanes), bit0 of
+ bitmap should be set, port=0x1; if target Root Port is 0000:00:04.0 (x4
+ lanes), bit8 is set, port=0x100; if these two Root Ports are both
+ monitored, port=0x101.
--bdf
+ Example usage of perf::
-"bdf" filter can only be used in bandwidth events, target Endpoint is selected
-by configuring BDF to "bdf". Counter only counts the bandwidth of message
-requested by target Endpoint.
+ $# perf stat -e hisi_pcie0_core0/rx_mwr_latency,port=0x1/ sleep 5
-For example, "bdf=0x3900" means BDF of target Endpoint is 0000:39:00.0.
+ - bdf
-Example usage of perf::
+ "bdf" filter can only be used in bandwidth events, target Endpoint is
+ selected by configuring BDF to "bdf". Counter only counts the bandwidth of
+ message requested by target Endpoint.
+
+ For example, "bdf=0x3900" means BDF of target Endpoint is 0000:39:00.0.
+
+ Example usage of perf::
- $# perf stat -e hisi_pcie0_0/rx_mrd_flux,bdf=0x3900/ sleep 5
+ $# perf stat -e hisi_pcie0_core0/rx_mrd_flux,bdf=0x3900/ sleep 5
2. Trigger filter
-Event statistics start when the first time TLP length is greater/smaller
-than trigger condition. You can set the trigger condition by writing "trig_len",
-and set the trigger mode by writing "trig_mode". This filter can only be used
-in bandwidth events.
-For example, "trig_len=4" means trigger condition is 2^4 DW, "trig_mode=0"
-means statistics start when TLP length > trigger condition, "trig_mode=1"
-means start when TLP length < condition.
+ Event statistics start when the first time TLP length is greater/smaller
+ than trigger condition. You can set the trigger condition by writing
+ "trig_len", and set the trigger mode by writing "trig_mode". This filter can
+ only be used in bandwidth events.
-Example usage of perf::
+ For example, "trig_len=4" means trigger condition is 2^4 DW, "trig_mode=0"
+ means statistics start when TLP length > trigger condition, "trig_mode=1"
+ means start when TLP length < condition.
+
+ Example usage of perf::
- $# perf stat -e hisi_pcie0_0/rx_mrd_flux,trig_len=0x4,trig_mode=1/ sleep 5
+ $# perf stat -e hisi_pcie0_core0/rx_mrd_flux,trig_len=0x4,trig_mode=1/ sleep 5
3. Threshold filter
-Counter counts when TLP length within the specified range. You can set the
-threshold by writing "thr_len", and set the threshold mode by writing
-"thr_mode". This filter can only be used in bandwidth events.
-For example, "thr_len=4" means threshold is 2^4 DW, "thr_mode=0" means
-counter counts when TLP length >= threshold, and "thr_mode=1" means counts
-when TLP length < threshold.
+ Counter counts when TLP length within the specified range. You can set the
+ threshold by writing "thr_len", and set the threshold mode by writing
+ "thr_mode". This filter can only be used in bandwidth events.
-Example usage of perf::
+ For example, "thr_len=4" means threshold is 2^4 DW, "thr_mode=0" means
+ counter counts when TLP length >= threshold, and "thr_mode=1" means counts
+ when TLP length < threshold.
+
+ Example usage of perf::
+
+ $# perf stat -e hisi_pcie0_core0/rx_mrd_flux,thr_len=0x4,thr_mode=1/ sleep 5
+
+4. TLP Length filter
+
+ When counting bandwidth, the data can be composed of certain parts of TLP
+ packets. You can specify it through "len_mode":
+
+ - 2'b00: Reserved (Do not use this since the behaviour is undefined)
+ - 2'b01: Bandwidth of TLP payloads
+ - 2'b10: Bandwidth of TLP headers
+ - 2'b11: Bandwidth of both TLP payloads and headers
+
+ For example, "len_mode=2" means only counting the bandwidth of TLP headers
+ and "len_mode=3" means the final bandwidth data is composed of both TLP
+ headers and payloads. Default value if not specified is 2'b11.
+
+ Example usage of perf::
- $# perf stat -e hisi_pcie0_0/rx_mrd_flux,thr_len=0x4,thr_mode=1/ sleep 5
+ $# perf stat -e hisi_pcie0_core0/rx_mrd_flux,len_mode=0x1/ sleep 5
diff --git a/Documentation/admin-guide/perf/index.rst b/Documentation/admin-guide/perf/index.rst
index 793e1970bc05..9de64a40adab 100644
--- a/Documentation/admin-guide/perf/index.rst
+++ b/Documentation/admin-guide/perf/index.rst
@@ -19,3 +19,5 @@ Performance monitor support
arm_dsu_pmu
thunderx2-pmu
alibaba_pmu
+ nvidia-pmu
+ meson-ddr-pmu
diff --git a/Documentation/admin-guide/perf/meson-ddr-pmu.rst b/Documentation/admin-guide/perf/meson-ddr-pmu.rst
new file mode 100644
index 000000000000..8e71be1d6346
--- /dev/null
+++ b/Documentation/admin-guide/perf/meson-ddr-pmu.rst
@@ -0,0 +1,70 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+===========================================================
+Amlogic SoC DDR Bandwidth Performance Monitoring Unit (PMU)
+===========================================================
+
+The Amlogic Meson G12 SoC contains a bandwidth monitor inside DRAM controller.
+The monitor includes 4 channels. Each channel can count the request accessing
+DRAM. The channel can count up to 3 AXI port simultaneously. It can be helpful
+to show if the performance bottleneck is on DDR bandwidth.
+
+Currently, this driver supports the following 5 perf events:
+
++ meson_ddr_bw/total_rw_bytes/
++ meson_ddr_bw/chan_1_rw_bytes/
++ meson_ddr_bw/chan_2_rw_bytes/
++ meson_ddr_bw/chan_3_rw_bytes/
++ meson_ddr_bw/chan_4_rw_bytes/
+
+meson_ddr_bw/chan_{1,2,3,4}_rw_bytes/ events are channel-specific events.
+Each channel support filtering, which can let the channel to monitor
+individual IP module in SoC.
+
+Below are DDR access request event filter keywords:
+
++ arm - from CPU
++ vpu_read1 - from OSD + VPP read
++ gpu - from 3D GPU
++ pcie - from PCIe controller
++ hdcp - from HDCP controller
++ hevc_front - from HEVC codec front end
++ usb3_0 - from USB3.0 controller
++ hevc_back - from HEVC codec back end
++ h265enc - from HEVC encoder
++ vpu_read2 - from DI read
++ vpu_write1 - from VDIN write
++ vpu_write2 - from di write
++ vdec - from legacy codec video decoder
++ hcodec - from H264 encoder
++ ge2d - from ge2d
++ spicc1 - from SPI controller 1
++ usb0 - from USB2.0 controller 0
++ dma - from system DMA controller 1
++ arb0 - from arb0
++ sd_emmc_b - from SD eMMC b controller
++ usb1 - from USB2.0 controller 1
++ audio - from Audio module
++ sd_emmc_c - from SD eMMC c controller
++ spicc2 - from SPI controller 2
++ ethernet - from Ethernet controller
+
+
+Examples:
+
+ + Show the total DDR bandwidth per seconds:
+
+ .. code-block:: bash
+
+ perf stat -a -e meson_ddr_bw/total_rw_bytes/ -I 1000 sleep 10
+
+
+ + Show individual DDR bandwidth from CPU and GPU respectively, as well as
+ sum of them:
+
+ .. code-block:: bash
+
+ perf stat -a -e meson_ddr_bw/chan_1_rw_bytes,arm=1/ -I 1000 sleep 10
+ perf stat -a -e meson_ddr_bw/chan_2_rw_bytes,gpu=1/ -I 1000 sleep 10
+ perf stat -a -e meson_ddr_bw/chan_3_rw_bytes,arm=1,gpu=1/ -I 1000 sleep 10
+
diff --git a/Documentation/admin-guide/perf/nvidia-pmu.rst b/Documentation/admin-guide/perf/nvidia-pmu.rst
new file mode 100644
index 000000000000..2e0d47cfe7ea
--- /dev/null
+++ b/Documentation/admin-guide/perf/nvidia-pmu.rst
@@ -0,0 +1,299 @@
+=========================================================
+NVIDIA Tegra SoC Uncore Performance Monitoring Unit (PMU)
+=========================================================
+
+The NVIDIA Tegra SoC includes various system PMUs to measure key performance
+metrics like memory bandwidth, latency, and utilization:
+
+* Scalable Coherency Fabric (SCF)
+* NVLink-C2C0
+* NVLink-C2C1
+* CNVLink
+* PCIE
+
+PMU Driver
+----------
+
+The PMUs in this document are based on ARM CoreSight PMU Architecture as
+described in document: ARM IHI 0091. Since this is a standard architecture, the
+PMUs are managed by a common driver "arm-cs-arch-pmu". This driver describes
+the available events and configuration of each PMU in sysfs. Please see the
+sections below to get the sysfs path of each PMU. Like other uncore PMU drivers,
+the driver provides "cpumask" sysfs attribute to show the CPU id used to handle
+the PMU event. There is also "associated_cpus" sysfs attribute, which contains a
+list of CPUs associated with the PMU instance.
+
+.. _SCF_PMU_Section:
+
+SCF PMU
+-------
+
+The SCF PMU monitors system level cache events, CPU traffic, and
+strongly-ordered (SO) PCIE write traffic to local/remote memory. Please see
+:ref:`NVIDIA_Uncore_PMU_Traffic_Coverage_Section` for more info about the PMU
+traffic coverage.
+
+The events and configuration options of this PMU device are described in sysfs,
+see /sys/bus/event_sources/devices/nvidia_scf_pmu_<socket-id>.
+
+Example usage:
+
+* Count event id 0x0 in socket 0::
+
+ perf stat -a -e nvidia_scf_pmu_0/event=0x0/
+
+* Count event id 0x0 in socket 1::
+
+ perf stat -a -e nvidia_scf_pmu_1/event=0x0/
+
+NVLink-C2C0 PMU
+--------------------
+
+The NVLink-C2C0 PMU monitors incoming traffic from a GPU/CPU connected with
+NVLink-C2C (Chip-2-Chip) interconnect. The type of traffic captured by this PMU
+varies dependent on the chip configuration:
+
+* NVIDIA Grace Hopper Superchip: Hopper GPU is connected with Grace SoC.
+
+ In this config, the PMU captures GPU ATS translated or EGM traffic from the GPU.
+
+* NVIDIA Grace CPU Superchip: two Grace CPU SoCs are connected.
+
+ In this config, the PMU captures read and relaxed ordered (RO) writes from
+ PCIE device of the remote SoC.
+
+Please see :ref:`NVIDIA_Uncore_PMU_Traffic_Coverage_Section` for more info about
+the PMU traffic coverage.
+
+The events and configuration options of this PMU device are described in sysfs,
+see /sys/bus/event_sources/devices/nvidia_nvlink_c2c0_pmu_<socket-id>.
+
+Example usage:
+
+* Count event id 0x0 from the GPU/CPU connected with socket 0::
+
+ perf stat -a -e nvidia_nvlink_c2c0_pmu_0/event=0x0/
+
+* Count event id 0x0 from the GPU/CPU connected with socket 1::
+
+ perf stat -a -e nvidia_nvlink_c2c0_pmu_1/event=0x0/
+
+* Count event id 0x0 from the GPU/CPU connected with socket 2::
+
+ perf stat -a -e nvidia_nvlink_c2c0_pmu_2/event=0x0/
+
+* Count event id 0x0 from the GPU/CPU connected with socket 3::
+
+ perf stat -a -e nvidia_nvlink_c2c0_pmu_3/event=0x0/
+
+NVLink-C2C1 PMU
+-------------------
+
+The NVLink-C2C1 PMU monitors incoming traffic from a GPU connected with
+NVLink-C2C (Chip-2-Chip) interconnect. This PMU captures untranslated GPU
+traffic, in contrast with NvLink-C2C0 PMU that captures ATS translated traffic.
+Please see :ref:`NVIDIA_Uncore_PMU_Traffic_Coverage_Section` for more info about
+the PMU traffic coverage.
+
+The events and configuration options of this PMU device are described in sysfs,
+see /sys/bus/event_sources/devices/nvidia_nvlink_c2c1_pmu_<socket-id>.
+
+Example usage:
+
+* Count event id 0x0 from the GPU connected with socket 0::
+
+ perf stat -a -e nvidia_nvlink_c2c1_pmu_0/event=0x0/
+
+* Count event id 0x0 from the GPU connected with socket 1::
+
+ perf stat -a -e nvidia_nvlink_c2c1_pmu_1/event=0x0/
+
+* Count event id 0x0 from the GPU connected with socket 2::
+
+ perf stat -a -e nvidia_nvlink_c2c1_pmu_2/event=0x0/
+
+* Count event id 0x0 from the GPU connected with socket 3::
+
+ perf stat -a -e nvidia_nvlink_c2c1_pmu_3/event=0x0/
+
+CNVLink PMU
+---------------
+
+The CNVLink PMU monitors traffic from GPU and PCIE device on remote sockets
+to local memory. For PCIE traffic, this PMU captures read and relaxed ordered
+(RO) write traffic. Please see :ref:`NVIDIA_Uncore_PMU_Traffic_Coverage_Section`
+for more info about the PMU traffic coverage.
+
+The events and configuration options of this PMU device are described in sysfs,
+see /sys/bus/event_sources/devices/nvidia_cnvlink_pmu_<socket-id>.
+
+Each SoC socket can be connected to one or more sockets via CNVLink. The user can
+use "rem_socket" bitmap parameter to select the remote socket(s) to monitor.
+Each bit represents the socket number, e.g. "rem_socket=0xE" corresponds to
+socket 1 to 3.
+/sys/bus/event_sources/devices/nvidia_cnvlink_pmu_<socket-id>/format/rem_socket
+shows the valid bits that can be set in the "rem_socket" parameter.
+
+The PMU can not distinguish the remote traffic initiator, therefore it does not
+provide filter to select the traffic source to monitor. It reports combined
+traffic from remote GPU and PCIE devices.
+
+Example usage:
+
+* Count event id 0x0 for the traffic from remote socket 1, 2, and 3 to socket 0::
+
+ perf stat -a -e nvidia_cnvlink_pmu_0/event=0x0,rem_socket=0xE/
+
+* Count event id 0x0 for the traffic from remote socket 0, 2, and 3 to socket 1::
+
+ perf stat -a -e nvidia_cnvlink_pmu_1/event=0x0,rem_socket=0xD/
+
+* Count event id 0x0 for the traffic from remote socket 0, 1, and 3 to socket 2::
+
+ perf stat -a -e nvidia_cnvlink_pmu_2/event=0x0,rem_socket=0xB/
+
+* Count event id 0x0 for the traffic from remote socket 0, 1, and 2 to socket 3::
+
+ perf stat -a -e nvidia_cnvlink_pmu_3/event=0x0,rem_socket=0x7/
+
+
+PCIE PMU
+------------
+
+The PCIE PMU monitors all read/write traffic from PCIE root ports to
+local/remote memory. Please see :ref:`NVIDIA_Uncore_PMU_Traffic_Coverage_Section`
+for more info about the PMU traffic coverage.
+
+The events and configuration options of this PMU device are described in sysfs,
+see /sys/bus/event_sources/devices/nvidia_pcie_pmu_<socket-id>.
+
+Each SoC socket can support multiple root ports. The user can use
+"root_port" bitmap parameter to select the port(s) to monitor, i.e.
+"root_port=0xF" corresponds to root port 0 to 3.
+/sys/bus/event_sources/devices/nvidia_pcie_pmu_<socket-id>/format/root_port
+shows the valid bits that can be set in the "root_port" parameter.
+
+Example usage:
+
+* Count event id 0x0 from root port 0 and 1 of socket 0::
+
+ perf stat -a -e nvidia_pcie_pmu_0/event=0x0,root_port=0x3/
+
+* Count event id 0x0 from root port 0 and 1 of socket 1::
+
+ perf stat -a -e nvidia_pcie_pmu_1/event=0x0,root_port=0x3/
+
+.. _NVIDIA_Uncore_PMU_Traffic_Coverage_Section:
+
+Traffic Coverage
+----------------
+
+The PMU traffic coverage may vary dependent on the chip configuration:
+
+* **NVIDIA Grace Hopper Superchip**: Hopper GPU is connected with Grace SoC.
+
+ Example configuration with two Grace SoCs::
+
+ ********************************* *********************************
+ * SOCKET-A * * SOCKET-B *
+ * * * *
+ * :::::::: * * :::::::: *
+ * : PCIE : * * : PCIE : *
+ * :::::::: * * :::::::: *
+ * | * * | *
+ * | * * | *
+ * ::::::: ::::::::: * * ::::::::: ::::::: *
+ * : : : : * * : : : : *
+ * : GPU :<--NVLink-->: Grace :<---CNVLink--->: Grace :<--NVLink-->: GPU : *
+ * : : C2C : SoC : * * : SoC : C2C : : *
+ * ::::::: ::::::::: * * ::::::::: ::::::: *
+ * | | * * | | *
+ * | | * * | | *
+ * &&&&&&&& &&&&&&&& * * &&&&&&&& &&&&&&&& *
+ * & GMEM & & CMEM & * * & CMEM & & GMEM & *
+ * &&&&&&&& &&&&&&&& * * &&&&&&&& &&&&&&&& *
+ * * * *
+ ********************************* *********************************
+
+ GMEM = GPU Memory (e.g. HBM)
+ CMEM = CPU Memory (e.g. LPDDR5X)
+
+ |
+ | Following table contains traffic coverage of Grace SoC PMU in socket-A:
+
+ ::
+
+ +--------------+-------+-----------+-----------+-----+----------+----------+
+ | | Source |
+ + +-------+-----------+-----------+-----+----------+----------+
+ | Destination | |GPU ATS |GPU Not-ATS| | Socket-B | Socket-B |
+ | |PCI R/W|Translated,|Translated | CPU | CPU/PCIE1| GPU/PCIE2|
+ | | |EGM | | | | |
+ +==============+=======+===========+===========+=====+==========+==========+
+ | Local | PCIE |NVLink-C2C0|NVLink-C2C1| SCF | SCF PMU | CNVLink |
+ | SYSRAM/CMEM | PMU |PMU |PMU | PMU | | PMU |
+ +--------------+-------+-----------+-----------+-----+----------+----------+
+ | Local GMEM | PCIE | N/A |NVLink-C2C1| SCF | SCF PMU | CNVLink |
+ | | PMU | |PMU | PMU | | PMU |
+ +--------------+-------+-----------+-----------+-----+----------+----------+
+ | Remote | PCIE |NVLink-C2C0|NVLink-C2C1| SCF | | |
+ | SYSRAM/CMEM | PMU |PMU |PMU | PMU | N/A | N/A |
+ | over CNVLink | | | | | | |
+ +--------------+-------+-----------+-----------+-----+----------+----------+
+ | Remote GMEM | PCIE |NVLink-C2C0|NVLink-C2C1| SCF | | |
+ | over CNVLink | PMU |PMU |PMU | PMU | N/A | N/A |
+ +--------------+-------+-----------+-----------+-----+----------+----------+
+
+ PCIE1 traffic represents strongly ordered (SO) writes.
+ PCIE2 traffic represents reads and relaxed ordered (RO) writes.
+
+* **NVIDIA Grace CPU Superchip**: two Grace CPU SoCs are connected.
+
+ Example configuration with two Grace SoCs::
+
+ ******************* *******************
+ * SOCKET-A * * SOCKET-B *
+ * * * *
+ * :::::::: * * :::::::: *
+ * : PCIE : * * : PCIE : *
+ * :::::::: * * :::::::: *
+ * | * * | *
+ * | * * | *
+ * ::::::::: * * ::::::::: *
+ * : : * * : : *
+ * : Grace :<--------NVLink------->: Grace : *
+ * : SoC : * C2C * : SoC : *
+ * ::::::::: * * ::::::::: *
+ * | * * | *
+ * | * * | *
+ * &&&&&&&& * * &&&&&&&& *
+ * & CMEM & * * & CMEM & *
+ * &&&&&&&& * * &&&&&&&& *
+ * * * *
+ ******************* *******************
+
+ GMEM = GPU Memory (e.g. HBM)
+ CMEM = CPU Memory (e.g. LPDDR5X)
+
+ |
+ | Following table contains traffic coverage of Grace SoC PMU in socket-A:
+
+ ::
+
+ +-----------------+-----------+---------+----------+-------------+
+ | | Source |
+ + +-----------+---------+----------+-------------+
+ | Destination | | | Socket-B | Socket-B |
+ | | PCI R/W | CPU | CPU/PCIE1| PCIE2 |
+ | | | | | |
+ +=================+===========+=========+==========+=============+
+ | Local | PCIE PMU | SCF PMU | SCF PMU | NVLink-C2C0 |
+ | SYSRAM/CMEM | | | | PMU |
+ +-----------------+-----------+---------+----------+-------------+
+ | Remote | | | | |
+ | SYSRAM/CMEM | PCIE PMU | SCF PMU | N/A | N/A |
+ | over NVLink-C2C | | | | |
+ +-----------------+-----------+---------+----------+-------------+
+
+ PCIE1 traffic represents strongly ordered (SO) writes.
+ PCIE2 traffic represents reads and relaxed ordered (RO) writes.
diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst
index 8f3d30c5a0d8..5376d53faaa8 100644
--- a/Documentation/admin-guide/pm/amd-pstate.rst
+++ b/Documentation/admin-guide/pm/amd-pstate.rst
@@ -283,23 +283,19 @@ efficiency frequency management method on AMD processors.
Kernel Module Options for ``amd-pstate``
=========================================
-.. _shared_mem:
+Passive Mode
+------------
-``shared_mem``
-Use a module param (shared_mem) to enable related processors manually with
-**amd_pstate.shared_mem=1**.
-Due to the performance issue on the processors with `Shared Memory Support
-<perf_cap_>`_, we disable it presently and will re-enable this by default
-once we address performance issue with this solution.
+``amd_pstate=passive``
-To check whether the current processor is using `Full MSR Support <perf_cap_>`_
-or `Shared Memory Support <perf_cap_>`_ : ::
-
- ray@hr-test1:~$ lscpu | grep cppc
- Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid aperfmperf rapl pni pclmulqdq monitor ssse3 fma cx16 sse4_1 sse4_2 x2apic movbe popcnt aes xsave avx f16c rdrand lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt tce topoext perfctr_core perfctr_nb bpext perfctr_llc mwaitx cpb cat_l3 cdp_l3 hw_pstate ssbd mba ibrs ibpb stibp vmmcall fsgsbase bmi1 avx2 smep bmi2 erms invpcid cqm rdt_a rdseed adx smap clflushopt clwb sha_ni xsaveopt xsavec xgetbv1 xsaves cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local clzero irperf xsaveerptr rdpru wbnoinvd cppc arat npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold avic v_vmsave_vmload vgif v_spec_ctrl umip pku ospke vaes vpclmulqdq rdpid overflow_recov succor smca fsrm
-
-If the CPU flags have ``cppc``, then this processor supports `Full MSR Support
-<perf_cap_>`_. Otherwise, it supports `Shared Memory Support <perf_cap_>`_.
+It will be enabled if the ``amd_pstate=passive`` is passed to the kernel in the command line.
+In this mode, ``amd_pstate`` driver software specifies a desired QoS target in the CPPC
+performance scale as a relative number. This can be expressed as percentage of nominal
+performance (infrastructure max). Below the nominal sustained performance level,
+desired performance expresses the average performance level of the processor subject
+to the Performance Reduction Tolerance register. Above the nominal performance level,
+processor must provide at least nominal performance requested and go higher if current
+operating conditions allow.
``cpupower`` tool support for ``amd-pstate``
@@ -409,37 +405,55 @@ Unit Tests for amd-pstate
1. Test case decriptions
+ 1). Basic tests
+
+ Test prerequisite and basic functions for the ``amd-pstate`` driver.
+
+---------+--------------------------------+------------------------------------------------------------------------------------+
| Index | Functions | Description |
+=========+================================+====================================================================================+
- | 0 | amd_pstate_ut_acpi_cpc_valid || Check whether the _CPC object is present in SBIOS. |
+ | 1 | amd_pstate_ut_acpi_cpc_valid || Check whether the _CPC object is present in SBIOS. |
| | || |
| | || The detail refer to `Processor Support <processor_support_>`_. |
+---------+--------------------------------+------------------------------------------------------------------------------------+
- | 1 | amd_pstate_ut_check_enabled || Check whether AMD P-State is enabled. |
+ | 2 | amd_pstate_ut_check_enabled || Check whether AMD P-State is enabled. |
| | || |
| | || AMD P-States and ACPI hardware P-States always can be supported in one processor. |
| | | But AMD P-States has the higher priority and if it is enabled with |
| | | :c:macro:`MSR_AMD_CPPC_ENABLE` or ``cppc_set_enable``, it will respond to the |
| | | request from AMD P-States. |
+---------+--------------------------------+------------------------------------------------------------------------------------+
- | 2 | amd_pstate_ut_check_perf || Check if the each performance values are reasonable. |
+ | 3 | amd_pstate_ut_check_perf || Check if the each performance values are reasonable. |
| | || highest_perf >= nominal_perf > lowest_nonlinear_perf > lowest_perf > 0. |
+---------+--------------------------------+------------------------------------------------------------------------------------+
- | 3 | amd_pstate_ut_check_freq || Check if the each frequency values and max freq when set support boost mode |
+ | 4 | amd_pstate_ut_check_freq || Check if the each frequency values and max freq when set support boost mode |
| | | are reasonable. |
| | || max_freq >= nominal_freq > lowest_nonlinear_freq > min_freq > 0 |
| | || If boost is not active but supported, this maximum frequency will be larger than |
| | | the one in ``cpuinfo``. |
+---------+--------------------------------+------------------------------------------------------------------------------------+
+ 2). Tbench test
+
+ Test and monitor the cpu changes when running tbench benchmark under the specified governor.
+ These changes include desire performance, frequency, load, performance, energy etc.
+ The specified governor is ondemand or schedutil.
+ Tbench can also be tested on the ``acpi-cpufreq`` kernel driver for comparison.
+
+ 3). Gitsource test
+
+ Test and monitor the cpu changes when running gitsource benchmark under the specified governor.
+ These changes include desire performance, frequency, load, time, energy etc.
+ The specified governor is ondemand or schedutil.
+ Gitsource can also be tested on the ``acpi-cpufreq`` kernel driver for comparison.
+
#. How to execute the tests
We use test module in the kselftest frameworks to implement it.
- We create amd-pstate-ut module and tie it into kselftest.(for
+ We create ``amd-pstate-ut`` module and tie it into kselftest.(for
details refer to Linux Kernel Selftests [4]_).
- 1. Build
+ 1). Build
+ open the :c:macro:`CONFIG_X86_AMD_PSTATE` configuration option.
+ set the :c:macro:`CONFIG_X86_AMD_PSTATE_UT` configuration option to M.
@@ -449,23 +463,159 @@ Unit Tests for amd-pstate
$ cd linux
$ make -C tools/testing/selftests
- #. Installation & Steps ::
+ + make perf ::
+
+ $ cd tools/perf/
+ $ make
+
+
+ 2). Installation & Steps ::
$ make -C tools/testing/selftests install INSTALL_PATH=~/kselftest
+ $ cp tools/perf/perf /usr/bin/perf
$ sudo ./kselftest/run_kselftest.sh -c amd-pstate
- TAP version 13
- 1..1
- # selftests: amd-pstate: amd-pstate-ut.sh
- # amd-pstate-ut: ok
- ok 1 selftests: amd-pstate: amd-pstate-ut.sh
-
- #. Results ::
-
- $ dmesg | grep "amd_pstate_ut" | tee log.txt
- [12977.570663] amd_pstate_ut: 1 amd_pstate_ut_acpi_cpc_valid success!
- [12977.570673] amd_pstate_ut: 2 amd_pstate_ut_check_enabled success!
- [12977.571207] amd_pstate_ut: 3 amd_pstate_ut_check_perf success!
- [12977.571212] amd_pstate_ut: 4 amd_pstate_ut_check_freq success!
+
+ 3). Specified test case ::
+
+ $ cd ~/kselftest/amd-pstate
+ $ sudo ./run.sh -t basic
+ $ sudo ./run.sh -t tbench
+ $ sudo ./run.sh -t tbench -m acpi-cpufreq
+ $ sudo ./run.sh -t gitsource
+ $ sudo ./run.sh -t gitsource -m acpi-cpufreq
+ $ ./run.sh --help
+ ./run.sh: illegal option -- -
+ Usage: ./run.sh [OPTION...]
+ [-h <help>]
+ [-o <output-file-for-dump>]
+ [-c <all: All testing,
+ basic: Basic testing,
+ tbench: Tbench testing,
+ gitsource: Gitsource testing.>]
+ [-t <tbench time limit>]
+ [-p <tbench process number>]
+ [-l <loop times for tbench>]
+ [-i <amd tracer interval>]
+ [-m <comparative test: acpi-cpufreq>]
+
+
+ 4). Results
+
+ + basic
+
+ When you finish test, you will get the following log info ::
+
+ $ dmesg | grep "amd_pstate_ut" | tee log.txt
+ [12977.570663] amd_pstate_ut: 1 amd_pstate_ut_acpi_cpc_valid success!
+ [12977.570673] amd_pstate_ut: 2 amd_pstate_ut_check_enabled success!
+ [12977.571207] amd_pstate_ut: 3 amd_pstate_ut_check_perf success!
+ [12977.571212] amd_pstate_ut: 4 amd_pstate_ut_check_freq success!
+
+ + tbench
+
+ When you finish test, you will get selftest.tbench.csv and png images.
+ The selftest.tbench.csv file contains the raw data and the drop of the comparative test.
+ The png images shows the performance, energy and performan per watt of each test.
+ Open selftest.tbench.csv :
+
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + Governor | Round | Des-perf | Freq | Load | Performance | Energy | Performance Per Watt |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + Unit | | | GHz | | MB/s | J | MB/J |
+ +=================================================+==============+==========+=========+==========+=============+=========+======================+
+ + amd-pstate-ondemand | 1 | | | | 2504.05 | 1563.67 | 158.5378 |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + amd-pstate-ondemand | 2 | | | | 2243.64 | 1430.32 | 155.2941 |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + amd-pstate-ondemand | 3 | | | | 2183.88 | 1401.32 | 154.2860 |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + amd-pstate-ondemand | Average | | | | 2310.52 | 1465.1 | 156.1268 |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + amd-pstate-schedutil | 1 | 165.329 | 1.62257 | 99.798 | 2136.54 | 1395.26 | 151.5971 |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + amd-pstate-schedutil | 2 | 166 | 1.49761 | 99.9993 | 2100.56 | 1380.5 | 150.6377 |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + amd-pstate-schedutil | 3 | 166 | 1.47806 | 99.9993 | 2084.12 | 1375.76 | 149.9737 |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + amd-pstate-schedutil | Average | 165.776 | 1.53275 | 99.9322 | 2107.07 | 1383.84 | 150.7399 |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-ondemand | 1 | | | | 2529.9 | 1564.4 | 160.0997 |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-ondemand | 2 | | | | 2249.76 | 1432.97 | 155.4297 |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-ondemand | 3 | | | | 2181.46 | 1406.88 | 153.5060 |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-ondemand | Average | | | | 2320.37 | 1468.08 | 156.4741 |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-schedutil | 1 | | | | 2137.64 | 1385.24 | 152.7723 |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-schedutil | 2 | | | | 2107.05 | 1372.23 | 152.0138 |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-schedutil | 3 | | | | 2085.86 | 1365.35 | 151.2433 |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-schedutil | Average | | | | 2110.18 | 1374.27 | 152.0136 |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-ondemand VS acpi-cpufreq-schedutil | Comprison(%) | | | | -9.0584 | -6.3899 | -2.8506 |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + amd-pstate-ondemand VS amd-pstate-schedutil | Comprison(%) | | | | 8.8053 | -5.5463 | -3.4503 |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-ondemand VS amd-pstate-ondemand | Comprison(%) | | | | -0.4245 | -0.2029 | -0.2219 |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-schedutil VS amd-pstate-schedutil | Comprison(%) | | | | -0.1473 | 0.6963 | -0.8378 |
+ +-------------------------------------------------+--------------+----------+---------+----------+-------------+---------+----------------------+
+
+ + gitsource
+
+ When you finish test, you will get selftest.gitsource.csv and png images.
+ The selftest.gitsource.csv file contains the raw data and the drop of the comparative test.
+ The png images shows the performance, energy and performan per watt of each test.
+ Open selftest.gitsource.csv :
+
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + Governor | Round | Des-perf | Freq | Load | Time | Energy | Performance Per Watt |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + Unit | | | GHz | | s | J | 1/J |
+ +=================================================+==============+==========+==========+==========+=============+=========+======================+
+ + amd-pstate-ondemand | 1 | 50.119 | 2.10509 | 23.3076 | 475.69 | 865.78 | 0.001155027 |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + amd-pstate-ondemand | 2 | 94.8006 | 1.98771 | 56.6533 | 467.1 | 839.67 | 0.001190944 |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + amd-pstate-ondemand | 3 | 76.6091 | 2.53251 | 43.7791 | 467.69 | 855.85 | 0.001168429 |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + amd-pstate-ondemand | Average | 73.8429 | 2.20844 | 41.2467 | 470.16 | 853.767 | 0.001171279 |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + amd-pstate-schedutil | 1 | 165.919 | 1.62319 | 98.3868 | 464.17 | 866.8 | 0.001153668 |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + amd-pstate-schedutil | 2 | 165.97 | 1.31309 | 99.5712 | 480.15 | 880.4 | 0.001135847 |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + amd-pstate-schedutil | 3 | 165.973 | 1.28448 | 99.9252 | 481.79 | 867.02 | 0.001153375 |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + amd-pstate-schedutil | Average | 165.954 | 1.40692 | 99.2944 | 475.37 | 871.407 | 0.001147569 |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-ondemand | 1 | | | | 2379.62 | 742.96 | 0.001345967 |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-ondemand | 2 | | | | 441.74 | 817.49 | 0.001223256 |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-ondemand | 3 | | | | 455.48 | 820.01 | 0.001219497 |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-ondemand | Average | | | | 425.613 | 793.487 | 0.001260260 |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-schedutil | 1 | | | | 459.69 | 838.54 | 0.001192548 |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-schedutil | 2 | | | | 466.55 | 830.89 | 0.001203528 |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-schedutil | 3 | | | | 470.38 | 837.32 | 0.001194286 |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-schedutil | Average | | | | 465.54 | 835.583 | 0.001196769 |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-ondemand VS acpi-cpufreq-schedutil | Comprison(%) | | | | 9.3810 | 5.3051 | -5.0379 |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + amd-pstate-ondemand VS amd-pstate-schedutil | Comprison(%) | 124.7392 | -36.2934 | 140.7329 | 1.1081 | 2.0661 | -2.0242 |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-ondemand VS amd-pstate-ondemand | Comprison(%) | | | | 10.4665 | 7.5968 | -7.0605 |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
+ + acpi-cpufreq-schedutil VS amd-pstate-schedutil | Comprison(%) | | | | 2.1115 | 4.2873 | -4.1110 |
+ +-------------------------------------------------+--------------+----------+----------+----------+-------------+---------+----------------------+
Reference
===========
diff --git a/Documentation/admin-guide/sysctl/fs.rst b/Documentation/admin-guide/sysctl/fs.rst
index 2a501c9ddc55..a321b84eccaa 100644
--- a/Documentation/admin-guide/sysctl/fs.rst
+++ b/Documentation/admin-guide/sysctl/fs.rst
@@ -2,8 +2,6 @@
Documentation for /proc/sys/fs/
===============================
-kernel version 2.2.10
-
Copyright (c) 1998, 1999, Rik van Riel <riel@nl.linux.org>
Copyright (c) 2009, Shen Feng<shen@cn.fujitsu.com>
@@ -12,58 +10,40 @@ For general info and legal blurb, please look in intro.rst.
------------------------------------------------------------------------------
-This file contains documentation for the sysctl files in
-/proc/sys/fs/ and is valid for Linux kernel version 2.2.
+This file contains documentation for the sysctl files and directories
+in ``/proc/sys/fs/``.
The files in this directory can be used to tune and monitor
miscellaneous and general things in the operation of the Linux
-kernel. Since some of the files _can_ be used to screw up your
+kernel. Since some of the files *can* be used to screw up your
system, it is advisable to read both documentation and source
before actually making adjustments.
1. /proc/sys/fs
===============
-Currently, these files are in /proc/sys/fs:
-
-- aio-max-nr
-- aio-nr
-- dentry-state
-- dquot-max
-- dquot-nr
-- file-max
-- file-nr
-- inode-max
-- inode-nr
-- inode-state
-- nr_open
-- overflowuid
-- overflowgid
-- pipe-user-pages-hard
-- pipe-user-pages-soft
-- protected_fifos
-- protected_hardlinks
-- protected_regular
-- protected_symlinks
-- suid_dumpable
-- super-max
-- super-nr
+Currently, these files might (depending on your configuration)
+show up in ``/proc/sys/fs``:
+
+.. contents:: :local:
aio-nr & aio-max-nr
-------------------
-aio-nr is the running total of the number of events specified on the
-io_setup system call for all currently active aio contexts. If aio-nr
-reaches aio-max-nr then io_setup will fail with EAGAIN. Note that
-raising aio-max-nr does not result in the pre-allocation or re-sizing
-of any kernel data structures.
+``aio-nr`` shows the current system-wide number of asynchronous io
+requests. ``aio-max-nr`` allows you to change the maximum value
+``aio-nr`` can grow to. If ``aio-nr`` reaches ``aio-nr-max`` then
+``io_setup`` will fail with ``EAGAIN``. Note that raising
+``aio-max-nr`` does not result in the
+pre-allocation or re-sizing of any kernel data structures.
dentry-state
------------
-From linux/include/linux/dcache.h::
+This file shows the values in ``struct dentry_stat``, as defined in
+``linux/include/linux/dcache.h``::
struct dentry_stat_t dentry_stat {
int nr_dentry;
@@ -76,95 +56,84 @@ From linux/include/linux/dcache.h::
Dentries are dynamically allocated and deallocated.
-nr_dentry shows the total number of dentries allocated (active
-+ unused). nr_unused shows the number of dentries that are not
+``nr_dentry`` shows the total number of dentries allocated (active
++ unused). ``nr_unused shows`` the number of dentries that are not
actively used, but are saved in the LRU list for future reuse.
-Age_limit is the age in seconds after which dcache entries
-can be reclaimed when memory is short and want_pages is
-nonzero when shrink_dcache_pages() has been called and the
+``age_limit`` is the age in seconds after which dcache entries
+can be reclaimed when memory is short and ``want_pages`` is
+nonzero when ``shrink_dcache_pages()`` has been called and the
dcache isn't pruned yet.
-nr_negative shows the number of unused dentries that are also
+``nr_negative`` shows the number of unused dentries that are also
negative dentries which do not map to any files. Instead,
they help speeding up rejection of non-existing files provided
by the users.
-dquot-max & dquot-nr
---------------------
-
-The file dquot-max shows the maximum number of cached disk
-quota entries.
-
-The file dquot-nr shows the number of allocated disk quota
-entries and the number of free disk quota entries.
-
-If the number of free cached disk quotas is very low and
-you have some awesome number of simultaneous system users,
-you might want to raise the limit.
-
-
file-max & file-nr
------------------
-The value in file-max denotes the maximum number of file-
+The value in ``file-max`` denotes the maximum number of file-
handles that the Linux kernel will allocate. When you get lots
of error messages about running out of file handles, you might
want to increase this limit.
Historically,the kernel was able to allocate file handles
dynamically, but not to free them again. The three values in
-file-nr denote the number of allocated file handles, the number
+``file-nr`` denote the number of allocated file handles, the number
of allocated but unused file handles, and the maximum number of
-file handles. Linux 2.6 always reports 0 as the number of free
+file handles. Linux 2.6 and later always reports 0 as the number of free
file handles -- this is not an error, it just means that the
number of allocated file handles exactly matches the number of
used file handles.
-Attempts to allocate more file descriptors than file-max are
-reported with printk, look for "VFS: file-max limit <number>
-reached".
+Attempts to allocate more file descriptors than ``file-max`` are
+reported with ``printk``, look for::
+ VFS: file-max limit <number> reached
-nr_open
--------
-
-This denotes the maximum number of file-handles a process can
-allocate. Default value is 1024*1024 (1048576) which should be
-enough for most machines. Actual limit depends on RLIMIT_NOFILE
-resource limit.
+in the kernel logs.
-inode-max, inode-nr & inode-state
----------------------------------
+inode-nr & inode-state
+----------------------
As with file handles, the kernel allocates the inode structures
dynamically, but can't free them yet.
-The value in inode-max denotes the maximum number of inode
-handlers. This value should be 3-4 times larger than the value
-in file-max, since stdin, stdout and network sockets also
-need an inode struct to handle them. When you regularly run
-out of inodes, you need to increase this value.
-
-The file inode-nr contains the first two items from
-inode-state, so we'll skip to that file...
+The file ``inode-nr`` contains the first two items from
+``inode-state``, so we'll skip to that file...
-Inode-state contains three actual numbers and four dummies.
-The actual numbers are, in order of appearance, nr_inodes,
-nr_free_inodes and preshrink.
+``inode-state`` contains three actual numbers and four dummies.
+The actual numbers are, in order of appearance, ``nr_inodes``,
+``nr_free_inodes`` and ``preshrink``.
-Nr_inodes stands for the number of inodes the system has
-allocated, this can be slightly more than inode-max because
-Linux allocates them one pageful at a time.
+``nr_inodes`` stands for the number of inodes the system has
+allocated.
-Nr_free_inodes represents the number of free inodes (?) and
-preshrink is nonzero when the nr_inodes > inode-max and the
+``nr_free_inodes`` represents the number of free inodes (?) and
+preshrink is nonzero when the
system needs to prune the inode list instead of allocating
more.
+mount-max
+---------
+
+This denotes the maximum number of mounts that may exist
+in a mount namespace.
+
+
+nr_open
+-------
+
+This denotes the maximum number of file-handles a process can
+allocate. Default value is 1024*1024 (1048576) which should be
+enough for most machines. Actual limit depends on ``RLIMIT_NOFILE``
+resource limit.
+
+
overflowgid & overflowuid
-------------------------
@@ -192,7 +161,7 @@ pipe-user-pages-soft
Maximum total number of pages a non-privileged user may allocate for pipes
before the pipe size gets limited to a single page. Once this limit is reached,
new pipes will be limited to a single page in size for this user in order to
-limit total memory usage, and trying to increase them using fcntl() will be
+limit total memory usage, and trying to increase them using ``fcntl()`` will be
denied until usage goes below the limit again. The default value allows to
allocate up to 1024 pipes at their default size. When set to 0, no limit is
applied.
@@ -207,7 +176,7 @@ file.
When set to "0", writing to FIFOs is unrestricted.
-When set to "1" don't allow O_CREAT open on FIFOs that we don't own
+When set to "1" don't allow ``O_CREAT`` open on FIFOs that we don't own
in world writable sticky directories, unless they are owned by the
owner of the directory.
@@ -221,7 +190,7 @@ protected_hardlinks
A long-standing class of security issues is the hardlink-based
time-of-check-time-of-use race, most commonly seen in world-writable
-directories like /tmp. The common method of exploitation of this flaw
+directories like ``/tmp``. The common method of exploitation of this flaw
is to cross privilege boundaries when following a given hardlink (i.e. a
root process follows a hardlink created by another user). Additionally,
on systems without separated partitions, this stops unauthorized users
@@ -239,13 +208,13 @@ This protection is based on the restrictions in Openwall and grsecurity.
protected_regular
-----------------
-This protection is similar to protected_fifos, but it
+This protection is similar to `protected_fifos`_, but it
avoids writes to an attacker-controlled regular file, where a program
expected to create one.
When set to "0", writing to regular files is unrestricted.
-When set to "1" don't allow O_CREAT open on regular files that we
+When set to "1" don't allow ``O_CREAT`` open on regular files that we
don't own in world writable sticky directories, unless they are
owned by the owner of the directory.
@@ -257,7 +226,7 @@ protected_symlinks
A long-standing class of security issues is the symlink-based
time-of-check-time-of-use race, most commonly seen in world-writable
-directories like /tmp. The common method of exploitation of this flaw
+directories like ``/tmp``. The common method of exploitation of this flaw
is to cross privilege boundaries when following a given symlink (i.e. a
root process follows a symlink belonging to another user). For a likely
incomplete list of hundreds of examples across the years, please see:
@@ -272,23 +241,25 @@ follower match, or when the directory owner matches the symlink's owner.
This protection is based on the restrictions in Openwall and grsecurity.
-suid_dumpable:
---------------
+suid_dumpable
+-------------
This value can be used to query and set the core dump mode for setuid
or otherwise protected/tainted binaries. The modes are
= ========== ===============================================================
-0 (default) traditional behaviour. Any process which has changed
+0 (default) Traditional behaviour. Any process which has changed
privilege levels or is execute only will not be dumped.
-1 (debug) all processes dump core when possible. The core dump is
+1 (debug) All processes dump core when possible. The core dump is
owned by the current user and no security is applied. This is
intended for system debugging situations only.
Ptrace is unchecked.
This is insecure as it allows regular users to examine the
memory contents of privileged processes.
-2 (suidsafe) any binary which normally would not be dumped is dumped
- anyway, but only if the "core_pattern" kernel sysctl is set to
+2 (suidsafe) Any binary which normally would not be dumped is dumped
+ anyway, but only if the ``core_pattern`` kernel sysctl (see
+ :ref:`Documentation/admin-guide/sysctl/kernel.rst <core_pattern>`)
+ is set to
either a pipe handler or a fully qualified path. (For more
details on this limitation, see CVE-2006-2451.) This mode is
appropriate when administrators are attempting to debug
@@ -301,36 +272,11 @@ or otherwise protected/tainted binaries. The modes are
= ========== ===============================================================
-super-max & super-nr
---------------------
-
-These numbers control the maximum number of superblocks, and
-thus the maximum number of mounted filesystems the kernel
-can have. You only need to increase super-max if you need to
-mount more filesystems than the current value in super-max
-allows you to.
-
-
-aio-nr & aio-max-nr
--------------------
-
-aio-nr shows the current system-wide number of asynchronous io
-requests. aio-max-nr allows you to change the maximum value
-aio-nr can grow to.
-
-
-mount-max
----------
-
-This denotes the maximum number of mounts that may exist
-in a mount namespace.
-
-
2. /proc/sys/fs/binfmt_misc
===========================
-Documentation for the files in /proc/sys/fs/binfmt_misc is
+Documentation for the files in ``/proc/sys/fs/binfmt_misc`` is
in Documentation/admin-guide/binfmt-misc.rst.
@@ -343,28 +289,32 @@ creation of a user space library that implements the POSIX message queues
API (as noted by the MSG tag in the POSIX 1003.1-2001 version of the System
Interfaces specification.)
-The "mqueue" filesystem contains values for determining/setting the amount of
-resources used by the file system.
+The "mqueue" filesystem contains values for determining/setting the
+amount of resources used by the file system.
-/proc/sys/fs/mqueue/queues_max is a read/write file for setting/getting the
-maximum number of message queues allowed on the system.
+``/proc/sys/fs/mqueue/queues_max`` is a read/write file for
+setting/getting the maximum number of message queues allowed on the
+system.
-/proc/sys/fs/mqueue/msg_max is a read/write file for setting/getting the
-maximum number of messages in a queue value. In fact it is the limiting value
-for another (user) limit which is set in mq_open invocation. This attribute of
-a queue must be less or equal then msg_max.
+``/proc/sys/fs/mqueue/msg_max`` is a read/write file for
+setting/getting the maximum number of messages in a queue value. In
+fact it is the limiting value for another (user) limit which is set in
+``mq_open`` invocation. This attribute of a queue must be less than
+or equal to ``msg_max``.
-/proc/sys/fs/mqueue/msgsize_max is a read/write file for setting/getting the
-maximum message size value (it is every message queue's attribute set during
-its creation).
+``/proc/sys/fs/mqueue/msgsize_max`` is a read/write file for
+setting/getting the maximum message size value (it is an attribute of
+every message queue, set during its creation).
-/proc/sys/fs/mqueue/msg_default is a read/write file for setting/getting the
-default number of messages in a queue value if attr parameter of mq_open(2) is
-NULL. If it exceed msg_max, the default value is initialized msg_max.
+``/proc/sys/fs/mqueue/msg_default`` is a read/write file for
+setting/getting the default number of messages in a queue value if the
+``attr`` parameter of ``mq_open(2)`` is ``NULL``. If it exceeds
+``msg_max``, the default value is initialized to ``msg_max``.
-/proc/sys/fs/mqueue/msgsize_default is a read/write file for setting/getting
-the default message size value if attr parameter of mq_open(2) is NULL. If it
-exceed msgsize_max, the default value is initialized msgsize_max.
+``/proc/sys/fs/mqueue/msgsize_default`` is a read/write file for
+setting/getting the default message size value if the ``attr``
+parameter of ``mq_open(2)`` is ``NULL``. If it exceeds
+``msgsize_max``, the default value is initialized to ``msgsize_max``.
4. /proc/sys/fs/epoll - Configuration options for the epoll interface
=====================================================================
@@ -378,7 +328,7 @@ Every epoll file descriptor can store a number of files to be monitored
for event readiness. Each one of these monitored files constitutes a "watch".
This configuration option sets the maximum number of "watches" that are
allowed for each user.
-Each "watch" costs roughly 90 bytes on a 32bit kernel, and roughly 160 bytes
-on a 64bit one.
-The current default value for max_user_watches is the 1/25 (4%) of the
-available low memory, divided for the "watch" cost in bytes.
+Each "watch" costs roughly 90 bytes on a 32-bit kernel, and roughly 160 bytes
+on a 64-bit one.
+The current default value for ``max_user_watches`` is 4% of the
+available low memory, divided by the "watch" cost in bytes.
diff --git a/Documentation/admin-guide/sysctl/kernel.rst b/Documentation/admin-guide/sysctl/kernel.rst
index 98d1b198b2b4..39e7a2d46e1e 100644
--- a/Documentation/admin-guide/sysctl/kernel.rst
+++ b/Documentation/admin-guide/sysctl/kernel.rst
@@ -139,6 +139,8 @@ Highest valid capability of the running kernel. Exports
``CAP_LAST_CAP`` from the kernel.
+.. _core_pattern:
+
core_pattern
============
@@ -174,6 +176,7 @@ core_pattern
%f executable filename
%E executable path
%c maximum size of core file by resource limit RLIMIT_CORE
+ %C CPU the task ran on
%<OTHER> both are dropped
======== ==========================================
@@ -1314,6 +1317,29 @@ watchdog work to be queued by the watchdog timer function, otherwise the NMI
watchdog — if enabled — can detect a hard lockup condition.
+split_lock_mitigate (x86 only)
+==============================
+
+On x86, each "split lock" imposes a system-wide performance penalty. On larger
+systems, large numbers of split locks from unprivileged users can result in
+denials of service to well-behaved and potentially more important users.
+
+The kernel mitigates these bad users by detecting split locks and imposing
+penalties: forcing them to wait and only allowing one core to execute split
+locks at a time.
+
+These mitigations can make those bad applications unbearably slow. Setting
+split_lock_mitigate=0 may restore some application performance, but will also
+increase system exposure to denial of service attacks from split lock users.
+
+= ===================================================================
+0 Disable the mitigation mode - just warns the split lock on kernel log
+ and exposes the system to denials of service from the split lockers.
+1 Enable the mitigation mode (this is the default) - penalizes the split
+ lockers with intentional performance degradation.
+= ===================================================================
+
+
stack_erasing
=============