diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-class-uwb_rc-wusbhc (renamed from Documentation/ABI/testing/sysfs-class-usb_host) | 4 | ||||
| -rw-r--r-- | Documentation/ABI/testing/sysfs-devices-cache_disable | 18 | ||||
| -rw-r--r-- | Documentation/ABI/testing/sysfs-devices-system-cpu | 156 | ||||
| -rw-r--r-- | Documentation/cputopology.txt | 47 | ||||
| -rw-r--r-- | Documentation/feature-removal-schedule.txt | 8 | ||||
| -rw-r--r-- | Documentation/filesystems/ext4.txt | 8 | ||||
| -rw-r--r-- | Documentation/flexible-arrays.txt | 43 | ||||
| -rw-r--r-- | Documentation/hwmon/sysfs-interface | 57 | ||||
| -rw-r--r-- | Documentation/i2c/busses/i2c-piix4 | 2 | ||||
| -rw-r--r-- | Documentation/lguest/lguest.c | 1 | ||||
| -rw-r--r-- | Documentation/sound/alsa/ALSA-Configuration.txt | 2 | ||||
| -rw-r--r-- | Documentation/thermal/sysfs-api.txt | 389 | ||||
| -rw-r--r-- | Documentation/trace/ftrace.txt | 2 | ||||
| -rw-r--r-- | Documentation/vm/hwpoison.txt | 136 |
14 files changed, 632 insertions, 241 deletions
diff --git a/Documentation/ABI/testing/sysfs-class-usb_host b/Documentation/ABI/testing/sysfs-class-uwb_rc-wusbhc index 46b66ad1f1b..4e8106f7cfd 100644 --- a/Documentation/ABI/testing/sysfs-class-usb_host +++ b/Documentation/ABI/testing/sysfs-class-uwb_rc-wusbhc @@ -1,4 +1,4 @@ -What: /sys/class/usb_host/usb_hostN/wusb_chid +What: /sys/class/uwb_rc/uwbN/wusbhc/wusb_chid Date: July 2008 KernelVersion: 2.6.27 Contact: David Vrabel <david.vrabel@csr.com> @@ -9,7 +9,7 @@ Description: Set an all zero CHID to stop the host controller. -What: /sys/class/usb_host/usb_hostN/wusb_trust_timeout +What: /sys/class/uwb_rc/uwbN/wusbhc/wusb_trust_timeout Date: July 2008 KernelVersion: 2.6.27 Contact: David Vrabel <david.vrabel@csr.com> diff --git a/Documentation/ABI/testing/sysfs-devices-cache_disable b/Documentation/ABI/testing/sysfs-devices-cache_disable deleted file mode 100644 index 175bb4f7051..00000000000 --- a/Documentation/ABI/testing/sysfs-devices-cache_disable +++ /dev/null @@ -1,18 +0,0 @@ -What: /sys/devices/system/cpu/cpu*/cache/index*/cache_disable_X -Date: August 2008 -KernelVersion: 2.6.27 -Contact: mark.langsdorf@amd.com -Description: These files exist in every cpu's cache index directories. - There are currently 2 cache_disable_# files in each - directory. Reading from these files on a supported - processor will return that cache disable index value - for that processor and node. Writing to one of these - files will cause the specificed cache index to be disabled. - - Currently, only AMD Family 10h Processors support cache index - disable, and only for their L3 caches. See the BIOS and - Kernel Developer's Guide at - http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/31116-Public-GH-BKDG_3.20_2-4-09.pdf - for formatting information and other details on the - cache index disable. -Users: joachim.deguara@amd.com diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu new file mode 100644 index 00000000000..a703b9e9aeb --- /dev/null +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu @@ -0,0 +1,156 @@ +What: /sys/devices/system/cpu/ +Date: pre-git history +Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> +Description: + A collection of both global and individual CPU attributes + + Individual CPU attributes are contained in subdirectories + named by the kernel's logical CPU number, e.g.: + + /sys/devices/system/cpu/cpu#/ + +What: /sys/devices/system/cpu/sched_mc_power_savings + /sys/devices/system/cpu/sched_smt_power_savings +Date: June 2006 +Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> +Description: Discover and adjust the kernel's multi-core scheduler support. + + Possible values are: + + 0 - No power saving load balance (default value) + 1 - Fill one thread/core/package first for long running threads + 2 - Also bias task wakeups to semi-idle cpu package for power + savings + + sched_mc_power_savings is dependent upon SCHED_MC, which is + itself architecture dependent. + + sched_smt_power_savings is dependent upon SCHED_SMT, which + is itself architecture dependent. + + The two files are independent of each other. It is possible + that one file may be present without the other. + + Introduced by git commit 5c45bf27. + + +What: /sys/devices/system/cpu/kernel_max + /sys/devices/system/cpu/offline + /sys/devices/system/cpu/online + /sys/devices/system/cpu/possible + /sys/devices/system/cpu/present +Date: December 2008 +Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> +Description: CPU topology files that describe kernel limits related to + hotplug. Briefly: + + kernel_max: the maximum cpu index allowed by the kernel + configuration. + + offline: cpus that are not online because they have been + HOTPLUGGED off or exceed the limit of cpus allowed by the + kernel configuration (kernel_max above). + + online: cpus that are online and being scheduled. + + possible: cpus that have been allocated resources and can be + brought online if they are present. + + present: cpus that have been identified as being present in + the system. + + See Documentation/cputopology.txt for more information. + + + +What: /sys/devices/system/cpu/cpu#/node +Date: October 2009 +Contact: Linux memory management mailing list <linux-mm@kvack.org> +Description: Discover NUMA node a CPU belongs to + + When CONFIG_NUMA is enabled, a symbolic link that points + to the corresponding NUMA node directory. + + For example, the following symlink is created for cpu42 + in NUMA node 2: + + /sys/devices/system/cpu/cpu42/node2 -> ../../node/node2 + + +What: /sys/devices/system/cpu/cpu#/topology/core_id + /sys/devices/system/cpu/cpu#/topology/core_siblings + /sys/devices/system/cpu/cpu#/topology/core_siblings_list + /sys/devices/system/cpu/cpu#/topology/physical_package_id + /sys/devices/system/cpu/cpu#/topology/thread_siblings + /sys/devices/system/cpu/cpu#/topology/thread_siblings_list +Date: December 2008 +Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> +Description: CPU topology files that describe a logical CPU's relationship + to other cores and threads in the same physical package. + + One cpu# directory is created per logical CPU in the system, + e.g. /sys/devices/system/cpu/cpu42/. + + Briefly, the files above are: + + core_id: the CPU core ID of cpu#. Typically it is the + hardware platform's identifier (rather than the kernel's). + The actual value is architecture and platform dependent. + + core_siblings: internal kernel map of cpu#'s hardware threads + within the same physical_package_id. + + core_siblings_list: human-readable list of the logical CPU + numbers within the same physical_package_id as cpu#. + + physical_package_id: physical package id of cpu#. Typically + corresponds to a physical socket number, but the actual value + is architecture and platform dependent. + + thread_siblings: internel kernel map of cpu#'s hardware + threads within the same core as cpu# + + thread_siblings_list: human-readable list of cpu#'s hardware + threads within the same core as cpu# + + See Documentation/cputopology.txt for more information. + + +What: /sys/devices/system/cpu/cpuidle/current_driver + /sys/devices/system/cpu/cpuidle/current_governer_ro +Date: September 2007 +Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> +Description: Discover cpuidle policy and mechanism + + Various CPUs today support multiple idle levels that are + differentiated by varying exit latencies and power + consumption during idle. + + Idle policy (governor) is differentiated from idle mechanism + (driver) + + current_driver: displays current idle mechanism + + current_governor_ro: displays current idle policy + + See files in Documentation/cpuidle/ for more information. + + +What: /sys/devices/system/cpu/cpu*/cache/index*/cache_disable_X +Date: August 2008 +KernelVersion: 2.6.27 +Contact: mark.langsdorf@amd.com +Description: These files exist in every cpu's cache index directories. + There are currently 2 cache_disable_# files in each + directory. Reading from these files on a supported + processor will return that cache disable index value + for that processor and node. Writing to one of these + files will cause the specificed cache index to be disabled. + + Currently, only AMD Family 10h Processors support cache index + disable, and only for their L3 caches. See the BIOS and + Kernel Developer's Guide at + http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/31116-Public-GH-BKDG_3.20_2-4-09.pdf + for formatting information and other details on the + cache index disable. +Users: joachim.deguara@amd.com diff --git a/Documentation/cputopology.txt b/Documentation/cputopology.txt index b41f3e58aef..f1c5c4bccd3 100644 --- a/Documentation/cputopology.txt +++ b/Documentation/cputopology.txt @@ -1,15 +1,28 @@ -Export cpu topology info via sysfs. Items (attributes) are similar +Export CPU topology info via sysfs. Items (attributes) are similar to /proc/cpuinfo. 1) /sys/devices/system/cpu/cpuX/topology/physical_package_id: -represent the physical package id of cpu X; + + physical package id of cpuX. Typically corresponds to a physical + socket number, but the actual value is architecture and platform + dependent. + 2) /sys/devices/system/cpu/cpuX/topology/core_id: -represent the cpu core id to cpu X; + + the CPU core ID of cpuX. Typically it is the hardware platform's + identifier (rather than the kernel's). The actual value is + architecture and platform dependent. + 3) /sys/devices/system/cpu/cpuX/topology/thread_siblings: -represent the thread siblings to cpu X in the same core; + + internel kernel map of cpuX's hardware threads within the same + core as cpuX + 4) /sys/devices/system/cpu/cpuX/topology/core_siblings: -represent the thread siblings to cpu X in the same physical package; + + internal kernel map of cpuX's hardware threads within the same + physical_package_id. To implement it in an architecture-neutral way, a new source file, drivers/base/topology.c, is to export the 4 attributes. @@ -32,32 +45,32 @@ not defined by include/asm-XXX/topology.h: 3) thread_siblings: just the given CPU 4) core_siblings: just the given CPU -Additionally, cpu topology information is provided under +Additionally, CPU topology information is provided under /sys/devices/system/cpu and includes these files. The internal source for the output is in brackets ("[]"). - kernel_max: the maximum cpu index allowed by the kernel configuration. + kernel_max: the maximum CPU index allowed by the kernel configuration. [NR_CPUS-1] - offline: cpus that are not online because they have been + offline: CPUs that are not online because they have been HOTPLUGGED off (see cpu-hotplug.txt) or exceed the limit - of cpus allowed by the kernel configuration (kernel_max + of CPUs allowed by the kernel configuration (kernel_max above). [~cpu_online_mask + cpus >= NR_CPUS] - online: cpus that are online and being scheduled [cpu_online_mask] + online: CPUs that are online and being scheduled [cpu_online_mask] - possible: cpus that have been allocated resources and can be + possible: CPUs that have been allocated resources and can be brought online if they are present. [cpu_possible_mask] - present: cpus that have been identified as being present in the + present: CPUs that have been identified as being present in the system. [cpu_present_mask] The format for the above output is compatible with cpulist_parse() [see <linux/cpumask.h>]. Some examples follow. -In this example, there are 64 cpus in the system but cpus 32-63 exceed +In this example, there are 64 CPUs in the system but cpus 32-63 exceed the kernel max which is limited to 0..31 by the NR_CPUS config option -being 32. Note also that cpus 2 and 4-31 are not online but could be +being 32. Note also that CPUs 2 and 4-31 are not online but could be brought online as they are both present and possible. kernel_max: 31 @@ -67,8 +80,8 @@ brought online as they are both present and possible. present: 0-31 In this example, the NR_CPUS config option is 128, but the kernel was -started with possible_cpus=144. There are 4 cpus in the system and cpu2 -was manually taken offline (and is the only cpu that can be brought +started with possible_cpus=144. There are 4 CPUs in the system and cpu2 +was manually taken offline (and is the only CPU that can be brought online.) kernel_max: 127 @@ -78,4 +91,4 @@ online.) present: 0-3 See cpu-hotplug.txt for the possible_cpus=NUM kernel start parameter -as well as more information on the various cpumask's. +as well as more information on the various cpumasks. diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 04e6c819b28..bc693fffabe 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -418,6 +418,14 @@ When: 2.6.33 Why: Should be implemented in userspace, policy daemon. Who: Johannes Berg <johannes@sipsolutions.net> +--------------------------- + +What: CONFIG_INOTIFY +When: 2.6.33 +Why: last user (audit) will be converted to the newer more generic + and more easily maintained fsnotify subsystem +Who: Eric Paris <eparis@redhat.com> + ---------------------------- What: lock_policy_rwsem_* and unlock_policy_rwsem_* will not be diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt index bf4f4b7e11b..6d94e0696f8 100644 --- a/Documentation/filesystems/ext4.txt +++ b/Documentation/filesystems/ext4.txt @@ -134,9 +134,15 @@ ro Mount filesystem read only. Note that ext4 will mount options "ro,noload" can be used to prevent writes to the filesystem. +journal_checksum Enable checksumming of the journal transactions. + This will allow the recovery code in e2fsck and the + kernel to detect corruption in the kernel. It is a + compatible change and will be ignored by older kernels. + journal_async_commit Commit block can be written to disk without waiting for descriptor blocks. If enabled older kernels cannot - mount the device. + mount the device. This will enable 'journal_checksum' + internally. journal=update Update the ext4 file system's journal to the current format. diff --git a/Documentation/flexible-arrays.txt b/Documentation/flexible-arrays.txt index 84eb26808de..cb8a3a00cc9 100644 --- a/Documentation/flexible-arrays.txt +++ b/Documentation/flexible-arrays.txt @@ -1,5 +1,5 @@ Using flexible arrays in the kernel -Last updated for 2.6.31 +Last updated for 2.6.32 Jonathan Corbet <corbet@lwn.net> Large contiguous memory allocations can be unreliable in the Linux kernel. @@ -40,6 +40,13 @@ argument is passed directly to the internal memory allocation calls. With the current code, using flags to ask for high memory is likely to lead to notably unpleasant side effects. +It is also possible to define flexible arrays at compile time with: + + DEFINE_FLEX_ARRAY(name, element_size, total); + +This macro will result in a definition of an array with the given name; the +element size and total will be checked for validity at compile time. + Storing data into a flexible array is accomplished with a call to: int flex_array_put(struct flex_array *array, unsigned int element_nr, @@ -76,16 +83,30 @@ particular element has never been allocated. Note that it is possible to get back a valid pointer for an element which has never been stored in the array. Memory for array elements is allocated one page at a time; a single allocation could provide memory for several -adjacent elements. The flexible array code does not know if a specific -element has been written; it only knows if the associated memory is -present. So a flex_array_get() call on an element which was never stored -in the array has the potential to return a pointer to random data. If the -caller does not have a separate way to know which elements were actually -stored, it might be wise, at least, to add GFP_ZERO to the flags argument -to ensure that all elements are zeroed. - -There is no way to remove a single element from the array. It is possible, -though, to remove all elements with a call to: +adjacent elements. Flexible array elements are normally initialized to the +value FLEX_ARRAY_FREE (defined as 0x6c in <linux/poison.h>), so errors +involving that number probably result from use of unstored array entries. +Note that, if array elements are allocated with __GFP_ZERO, they will be +initialized to zero and this poisoning will not happen. + +Individual elements in the array can be cleared with: + + int flex_array_clear(struct flex_array *array, unsigned int element_nr); + +This function will set the given element to FLEX_ARRAY_FREE and return +zero. If storage for the indicated element is not allocated for the array, +flex_array_clear() will return -EINVAL instead. Note that clearing an +element does not release the storage associated with it; to reduce the +allocated size of an array, call: + + int flex_array_shrink(struct flex_array *array); + +The return value will be the number of pages of memory actually freed. +This function works by scanning the array for pages containing nothing but +FLEX_ARRAY_FREE bytes, so (1) it can be expensive, and (2) it will not work +if the array's pages are allocated with __GFP_ZERO. + +It is possible to remove all elements of an array with a call to: void flex_array_free_parts(struct flex_array *array); diff --git a/Documentation/hwmon/sysfs-interface b/Documentation/hwmon/sysfs-interface index dcbd502c879..82def883361 100644 --- a/Documentation/hwmon/sysfs-interface +++ b/Documentation/hwmon/sysfs-interface @@ -353,10 +353,20 @@ power[1-*]_average Average power use Unit: microWatt RO -power[1-*]_average_interval Power use averaging interval +power[1-*]_average_interval Power use averaging interval. A poll + notification is sent to this file if the + hardware changes the averaging interval. Unit: milliseconds RW +power[1-*]_average_interval_max Maximum power use averaging interval + Unit: milliseconds + RO + +power[1-*]_average_interval_min Minimum power use averaging interval + Unit: milliseconds + RO + power[1-*]_average_highest Historical average maximum power use Unit: microWatt RO @@ -365,6 +375,18 @@ power[1-*]_average_lowest Historical average minimum power use Unit: microWatt RO +power[1-*]_average_max A poll notification is sent to + power[1-*]_average when power use + rises above this value. + Unit: microWatt + RW + +power[1-*]_average_min A poll notification is sent to + power[1-*]_average when power use + sinks below this value. + Unit: microWatt + RW + power[1-*]_input Instantaneous power use Unit: microWatt RO @@ -381,6 +403,39 @@ power[1-*]_reset_history Reset input_highest, input_lowest, average_highest and average_lowest. WO +power[1-*]_accuracy Accuracy of the power meter. + Unit: Percent + RO + +power[1-*]_alarm 1 if the system is drawing more power than the + cap allows; 0 otherwise. A poll notification is + sent to this file when the power use exceeds the + cap. This file only appears if the cap is known + to be enforced by hardware. + RO + +power[1-*]_cap If power use rises above this limit, the + system should take action to reduce power use. + A poll notification is sent to this file if the + cap is changed by the hardware. The *_cap + files only appear if the cap is known to be + enforced by hardware. + Unit: microWatt + RW + +power[1-*]_cap_hyst Margin of hysteresis built around capping and + notification. + Unit: microWatt + RW + +power[1-*]_cap_max Maximum cap that can be set. + Unit: microWatt + RO + +power[1-*]_cap_min Minimum cap that can be set. + Unit: microWatt + RO + ********** * Energy * ********** diff --git a/Documentation/i2c/busses/i2c-piix4 b/Documentation/i2c/busses/i2c-piix4 index c5b37c57055..ac540c71c7e 100644 --- a/Documentation/i2c/busses/i2c-piix4 +++ b/Documentation/i2c/busses/i2c-piix4 @@ -8,7 +8,7 @@ Supported adapters: Datasheet: Only available via NDA from ServerWorks * ATI IXP200, IXP300, IXP400, SB600, SB700 and SB800 southbridges Datasheet: Not publicly available - * AMD SB900 + * AMD Hudson-2 Datasheet: Not publicly available * Standard Microsystems (SMSC) SLC90E66 (Victory66) southbridge Datasheet: Publicly available at the SMSC website http://www.smsc.com diff --git a/Documentation/lguest/lguest.c b/Documentation/lguest/lguest.c index ba9373f82ab..098de5bce00 100644 --- a/Documentation/lguest/lguest.c +++ b/Documentation/lguest/lguest.c @@ -42,7 +42,6 @@ #include <signal.h> #include "linux/lguest_launcher.h" #include "linux/virtio_config.h" -#include <linux/virtio_ids.h> #include "linux/virtio_net.h" #include "linux/virtio_blk.h" #include "linux/virtio_console.h" diff --git a/Documentation/sound/alsa/ALSA-Configuration.txt b/Documentation/sound/alsa/ALSA-Configuration.txt index 1c8eb4518ce..fd9a2f67edf 100644 --- a/Documentation/sound/alsa/ALSA-Configuration.txt +++ b/Documentation/sound/alsa/ALSA-Configuration.txt @@ -522,7 +522,7 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed. pcm_devs - Number of PCM devices assigned to each card (default = 1, up to 4) pcm_substreams - Number of PCM substreams assigned to each PCM - (default = 8, up to 16) + (default = 8, up to 128) hrtimer - Use hrtimer (=1, default) or system timer (=0) fake_buffer - Fake buffer allocations (default = 1) diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt index 70d68ce8640..a87dc277a5c 100644 --- a/Documentation/thermal/sysfs-api.txt +++ b/Documentation/thermal/sysfs-api.txt @@ -1,5 +1,5 @@ Generic Thermal Sysfs driver How To -========================= +=================================== Written by Sujith Thomas <sujith.thomas@intel.com>, Zhang Rui <rui.zhang@intel.com> @@ -10,20 +10,20 @@ Copyright (c) 2008 Intel Corporation 0. Introduction -The generic thermal sysfs provides a set of interfaces for thermal zone devices (sensors) -and thermal cooling devices (fan, processor...) to register with the thermal management -solution and to be a part of it. +The generic thermal sysfs provides a set of interfaces for thermal zone +devices (sensors) and thermal cooling devices (fan, processor...) to register +with the thermal management solution and to be a part of it. -This how-to focuses on enabling new thermal zone and cooling devices to participate -in thermal management. -This solution is platform independent and any type of thermal zone devices and -cooling devices should be able to make use of the infrastructure. +This how-to focuses on enabling new thermal zone and cooling devices to +participate in thermal management. +This solution is platform independent and any type of thermal zone devices +and cooling devices should be able to make use of the infrastructure. -The main task of the thermal sysfs driver is to expose thermal zone attributes as well -as cooling device attributes to the user space. -An intelligent thermal management application can make decisions based on inputs -from thermal zone attributes (the current temperature and trip point temperature) -and throttle appropriate devices. +The main task of the thermal sysfs driver is to expose thermal zone attributes +as well as cooling device attributes to the user space. +An intelligent thermal management application can make decisions based on +inputs from thermal zone attributes (the current temperature and trip point +temperature) and throttle appropriate devices. [0-*] denotes any positive number starting from 0 [1-*] denotes any positive number starting from 1 @@ -31,77 +31,77 @@ and throttle appropriate devices. 1. thermal sysfs driver interface functions 1.1 thermal zone device interface -1.1.1 struct thermal_zone_device *thermal_zone_device_register(char *name, int trips, - void *devdata, struct thermal_zone_device_ops *ops) - - This interface function adds a new thermal zone device (sensor) to - /sys/class/thermal folder as thermal_zone[0-*]. - It tries to bind all the thermal cooling devices registered at the same time. - - name: the thermal zone name. - trips: the total number of trip points this thermal zone supports. - devdata: device private data - ops: thermal zone device call-backs. - .bind: bind the thermal zone device with a thermal cooling device. - .unbind: unbind the thermal zone device with a thermal cooling device. - .get_temp: get the current temperature of the thermal zone. - .get_mode: get the current mode (user/kernel) of the thermal zone. - "kernel" means thermal management is done in kernel. - "user" will prevent kernel thermal driver actions upon trip points - so that user applications can take charge of thermal management. - .set_mode: set the mode (user/kernel) of the thermal zone. - .get_trip_type: get the type of certain trip point. - .get_trip_temp: get the temperature above which the certain trip point - will be fired. +1.1.1 struct thermal_zone_device *thermal_zone_device_register(char *name, + int trips, void *devdata, struct thermal_zone_device_ops *ops) + + This interface function adds a new thermal zone device (sensor) to + /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the + thermal cooling devices registered at the same time. + + name: the thermal zone name. + trips: the total number of trip points this thermal zone supports. + devdata: device private data + ops: thermal zone device call-backs. + .bind: bind the thermal zone device with a thermal cooling device. + .unbind: unbind the thermal zone device with a thermal cooling device. + .get_temp: get the current temperature of the thermal zone. + .get_mode: get the current mode (user/kernel) of the thermal zone. + - "kernel" means thermal management is done in kernel. + - "user" will prevent kernel thermal driver actions upon trip points + so that user applications can take charge of thermal management. + .set_mode: set the mode (user/kernel) of the thermal zone. + .get_trip_type: get the type of certain trip point. + .get_trip_temp: get the temperature above which the certain trip point + will be fired. 1.1.2 void thermal_zone_device_unregister(struct thermal_zone_device *tz) - This interface function removes the thermal zone device. - It deletes the corresponding entry form /sys/class/thermal folder and unbind all - the thermal cooling devices it uses. + This interface function removes the thermal zone device. + It deletes the corresponding entry form /sys/class/thermal folder and + unbind all the thermal cooling devices it uses. 1.2 thermal cooling device interface 1.2.1 struct thermal_cooling_device *thermal_cooling_device_register(char *name, - void *devdata, struct thermal_cooling_device_ops *) - - This interface function adds a new thermal cooling device (fan/processor/...) to - /sys/class/thermal/ folder as cooling_device[0-*]. - It tries to bind itself to all the thermal zone devices register at the same time. - name: the cooling device name. - devdata: device private data. - ops: thermal cooling devices call-backs. - .get_max_state: get the Maximum throttle state of the cooling device. - .get_cur_state: get the Current throttle state of the cooling device. - .set_cur_state: set the Current throttle state of the cooling device. + void *devdata, struct thermal_cooling_device_ops *) + + This interface function adds a new thermal cooling device (fan/processor/...) + to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself + to all the thermal zone devices register at the same time. + name: the cooling device name. + devdata: device private data. + ops: thermal cooling devices call-backs. + .get_max_state: get the Maximum throttle state of the cooling device. + .get_cur_state: get the Current throttle state of the cooling device. + .set_cur_state: set the Current throttle state of the cooling device. 1.2.2 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev) - This interface function remove the thermal cooling device. - It deletes the corresponding entry form /sys/class/thermal folder and unbind - itself from all the thermal zone devices using it. + This interface function remove the thermal cooling device. + It deletes the corresponding entry form /sys/class/thermal folder and + unbind itself from all the thermal zone devices using it. 1.3 interface for binding a thermal zone device with a thermal cooling device 1.3.1 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz, - int trip, struct thermal_cooling_device *cdev); + int trip, struct thermal_cooling_device *cdev); - This interface function bind a thermal cooling device to the certain trip point - of a thermal zone device. - This function is usually called in the thermal zone device .bind callback. - tz: the thermal zone device - cdev: thermal cooling device - trip: indicates which trip point the cooling devices is associated with - in this thermal zone. + This interface function bind a thermal cooling device to the certain trip + point of a thermal zone device. + This function is usually called in the thermal zone device .bind callback. + tz: the thermal zone device + cdev: thermal cooling device + trip: indicates which trip point the cooling devices is associated with + in this thermal zone. 1.3.2 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz, - int trip, struct thermal_cooling_device *cdev); + int trip, struct thermal_cooling_device *cdev); - This interface function unbind a thermal cooling device from the certain trip point - of a thermal zone device. - This function is usually called in the thermal zone device .unbind callback. - tz: the thermal zone device - cdev: thermal cooling device - trip: indicates which trip point the cooling devices is associated with - in this thermal zone. + This interface function unbind a thermal cooling device from the certain + trip point of a thermal zone device. This function is usually called in + the thermal zone device .unbind callback. + tz: the thermal zone device + cdev: thermal cooling device + trip: indicates which trip point the cooling devices is associated with + in this thermal zone. 2. sysfs attributes structure @@ -114,153 +114,166 @@ if hwmon is compiled in or built as a module. Thermal zone device sys I/F, created once it's registered: /sys/class/thermal/thermal_zone[0-*]: - |-----type: Type of the thermal zone - |-----temp: Current temperature - |-----mode: Working mode of the thermal zone - |-----trip_point_[0-*]_temp: Trip point temperature - |-----trip_point_[0-*]_type: Trip point type + |---type: Type of the thermal zone + |---temp: Current temperature + |---mode: Working mode of the thermal zone + |---trip_point_[0-*]_temp: Trip point temperature + |---trip_point_[0-*]_type: Trip point type Thermal cooling device sys I/F, created once it's registered: /sys/class/thermal/cooling_device[0-*]: - |-----type : Type of the cooling device(processor/fan/...) - |-----max_state: Maximum cooling state of the cooling device - |-----cur_state: Current cooling state of the cooling device + |---type: Type of the cooling device(processor/fan/...) + |---max_state: Maximum cooling state of the cooling device + |---cur_state: Current cooling state of the cooling device -These two dynamic attributes are created/removed in pairs. -They represent the relationship between a thermal zone and its associated cooling device. -They are created/removed for each -thermal_zone_bind_cooling_device/thermal_zone_unbind_cooling_device successful execution. +Then next two dynamic attributes are created/removed in pairs. They represent +the relationship between a thermal zone and its associated cooling device. +They are created/removed for each successful execution of +thermal_zone_bind_cooling_device/thermal_zone_unbind_cooling_device. -/sys/class/thermal/thermal_zone[0-*] - |-----cdev[0-*]: The [0-*]th cooling device in the current thermal zone - |-----cdev[0-*]_trip_point: Trip point that cdev[0-*] is associated with +/sys/class/thermal/thermal_zone[0-*]: + |---cdev[0-*]: [0-*]th cooling device in current thermal zone + |---cdev[0-*]_trip_point: Trip point that cdev[0-*] is associated with Besides the thermal zone device sysfs I/F and cooling device sysfs I/F, -the generic thermal driver also creates a hwmon sysfs I/F for each _type_ of -thermal zone device. E.g. the generic thermal driver registers one hwmon class device -and build the associated hwmon sysfs I/F for all the registered ACPI thermal zones. +the generic thermal driver also creates a hwmon sysfs I/F for each _type_ +of thermal zone device. E.g. the generic thermal driver registers one hwmon +class device and build the associated hwmon sysfs I/F for all the registered +ACPI thermal zones. + /sys/class/hwmon/hwmon[0-*]: - |-----name: The type of the thermal zone devices. - |-----temp[1-*]_input: The current temperature of thermal zone [1-*]. - |-----temp[1-*]_critical: The critical trip point of thermal zone [1-*]. + |---name: The type of the thermal zone devices + |---temp[1-*]_input: The current temperature of thermal zone [1-*] + |---temp[1-*]_critical: The critical trip point of thermal zone [1-*] + Please read Documentation/hwmon/sysfs-interface for additional information. *************************** * Thermal zone attributes * *************************** -type Strings which represent the thermal zone type. - This is given by thermal zone driver as part of registration. - Eg: "acpitz" indicates it's an ACPI thermal device. - In order to keep it consistent with hwmon sys attribute, - this should be a short, lowercase string, - not containing spaces nor dashes. - RO - Required - -temp Current temperature as reported by thermal zone (sensor) - Unit: millidegree Celsius - RO - Required - -mode One of the predefined values in [kernel, user] - This file gives information about the algorithm - that is currently managing the thermal zone. - It can be either default kernel based algorithm - or user space application. - RW - Optional - kernel = Thermal management in kernel thermal zone driver. - user = Preventing kernel thermal zone driver actions upon - trip points so that user application can take full - charge of the thermal management. - -trip_point_[0-*]_temp The temperature above which trip point will be fired - Unit: millidegree Celsius - RO - Optional - -trip_point_[0-*]_type Strings which indicate the type of the trip point - E.g. it can be one of critical, hot, passive, - active[0-*] for ACPI thermal zone. - RO - Optional - -cdev[0-*] Sysfs link to the thermal cooling device node where the sys I/F - for cooling device throttling control represents. - RO - Optional - -cdev[0-*]_trip_point The trip point with which cdev[0-*] is associated in this thermal zone - -1 means the cooling device is not associated with any trip point. - RO - Optional - -****************************** -* Cooling device attributes * -****************************** - -type String which represents the type of device - eg: For generic ACPI: this should be "Fan", - "Processor" or "LCD" - eg. For memory controller device on intel_menlow platform: - this should be "Memory controller" - RO - Required - -max_state The maximum permissible cooling state of this cooling device. - RO - Required - -cur_state The current cooling state of this cooling device. - the value can any integer numbers between 0 and max_state, - cur_state == 0 means no cooling - cur_state == max_state means the maximum cooling. - RW - Required +type + Strings which represent the thermal zone type. + This is given by thermal zone driver as part of registration. + E.g: "acpitz" indicates it's an ACPI thermal device. + In order to keep it consistent with hwmon sys attribute; this should + be a short, lowercase string, not containing spaces nor dashes. + RO, Required + +temp + Current temperature as reported by thermal zone (sensor). + Unit: millidegree Celsius + RO, Required + +mode + One of the predefined values in [kernel, user]. + This file gives information about the algorithm that is currently + managing the thermal zone. It can be either default kernel based + algorithm or user space application. + kernel = Thermal management in kernel thermal zone driver. + user = Preventing kernel thermal zone driver actions upon + trip points so that user application can take full + charge of the thermal management. + RW, Optional + +trip_point_[0-*]_temp + The temperature above which trip point will be fired. + Unit: millidegree Celsius + RO, Optional + +trip_point_[0-*]_type + Strings which indicate the type of the trip point. + E.g. it can be one of critical, hot, passive, active[0-*] for ACPI + thermal zone. + RO, Optional + +cdev[0-*] + Sysfs link to the thermal cooling device node where the sys I/F + for cooling device throttling control represents. + RO, Optional + +cdev[0-*]_trip_point + The trip point with which cdev[0-*] is associated in this thermal + zone; -1 means the cooling device is not associated with any trip + point. + RO, Optional + +passive + Attribute is only present for zones in which the passive cooling + policy is not supported by native thermal driver. Default is zero + and can be set to a temperature (in millidegrees) to enable a + passive trip point for the zone. Activation is done by polling with + an interval of 1 second. + Unit: millidegrees Celsius + RW, Optional + +***************************** +* Cooling device attributes * +***************************** + +type + String which represents the type of device, e.g: + - for generic ACPI: should be "Fan", "Processor" or "LCD" + - for memory controller device on intel_menlow platform: + should be "Memory controller". + RO, Required + +max_state + The maximum permissible cooling state of this cooling device. + RO, Required + +cur_state + The current cooling state of this cooling device. + The value can any integer numbers between 0 and max_state: + - cur_state == 0 means no cooling + - cur_state == max_state means the maximum cooling. + RW, Required 3. A simple implementation -ACPI thermal zone may support multiple trip points like critical/hot/passive/active. -If an ACPI thermal zone supports critical, passive, active[0] and active[1] at the same time, -it may register itself as a thermal_zone_device (thermal_zone1) with 4 trip points in all. -It has one processor and one fan, which are both registered as thermal_cooling_device. -If the processor is listed in _PSL method, and the fan is listed in _AL0 method, -the sys I/F structure will be built like this: +ACPI thermal zone may support multiple trip points like critical, hot, +passive, active. If an ACPI thermal zone supports critical, passive, +active[0] and active[1] at the same time, it may register itself as a +thermal_zone_device (thermal_zone1) with 4 trip points in all. +It has one processor and one fan, which are both registered as +thermal_cooling_device. + +If the processor is listed in _PSL method, and the fan is listed in _AL0 +method, the sys I/F structure will be built like this: /sys/class/thermal: |thermal_zone1: - |-----type: acpitz - |-----temp: 37000 - |-----mode: kernel - |-----trip_point_0_temp: 100000 - |-----trip_point_0_type: critical - |-----trip_point_1_temp: 80000 - |-----trip_point_1_type: passive - |-----trip_point_2_temp: 70000 - |-----trip_point_2_type: active0 - |-----trip_point_3_temp: 60000 - |-----trip_point_3_type: active1 - |-----cdev0: --->/sys/class/thermal/cooling_device0 - |-----cdev0_trip_point: 1 /* cdev0 can be used for passive */ - |-----cdev1: --->/sys/class/thermal/cooling_device3 - |-----cdev1_trip_point: 2 /* cdev1 can be used for active[0]*/ + |---type: acpitz + |---temp: 37000 + |---mode: kernel + |---trip_point_0_temp: 100000 + |---trip_point_0_type: critical + |---trip_point_1_temp: 80000 + |---trip_point_1_type: passive + |---trip_point_2_temp: 70000 + |---trip_point_2_type: active0 + |---trip_point_3_temp: 60000 + |---trip_point_3_type: active1 + |---cdev0: --->/sys/class/thermal/cooling_device0 + |---cdev0_trip_point: 1 /* cdev0 can be used for passive */ + |---cdev1: --->/sys/class/thermal/cooling_device3 + |---cdev1_trip_point: 2 /* cdev1 can be used for active[0]*/ |cooling_device0: - |-----type: Processor - |-----max_state: 8 - |-----cur_state: 0 + |---type: Processor + |---max_state: 8 + |---cur_state: 0 |cooling_device3: - |-----type: Fan - |-----max_state: 2 - |-----cur_state: 0 + |---type: Fan + |---max_state: 2 + |---cur_state: 0 /sys/class/hwmon: |hwmon0: - |-----name: acpitz - |-----temp1_input: 37000 - |-----temp1_crit: 100000 + |---name: acpitz + |---temp1_input: 37000 + |---temp1_crit: 100000 diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt index 957b22fde2d..8179692fbb9 100644 --- a/Documentation/trace/ftrace.txt +++ b/Documentation/trace/ftrace.txt @@ -1231,6 +1231,7 @@ something like this simple program: #include <sys/stat.h> #include <fcntl.h> #include <unistd.h> +#include <string.h> #define _STR(x) #x #define STR(x) _STR(x) @@ -1265,6 +1266,7 @@ const char *find_debugfs(void) return NULL; } + strcat(debugfs, "/tracing/"); debugfs_found = 1; return debugfs; diff --git a/Documentation/vm/hwpoison.txt b/Documentation/vm/hwpoison.txt new file mode 100644 index 00000000000..3ffadf8da61 --- /dev/null +++ b/Documentation/vm/hwpoison.txt @@ -0,0 +1,136 @@ +What is hwpoison? + +Upcoming Intel CPUs have support for recovering from some memory errors +(``MCA recovery''). This requires the OS to declare a page "poisoned", +kill the processes associated with it and avoid using it in the future. + +This patchkit implements the necessary infrastructure in the VM. + +To quote the overview comment: + + * High level machine check handler. Handles pages reported by the + * hardware as being corrupted usually due to a 2bit ECC memory or cache + * failure. + * + * This focusses on pages detected as corrupted in the background. + * When the current CPU tries to consume corruption the currently + * running process can just be killed directly instead. This implies + * that if the error cannot be handled for some reason it's safe to + * just ignore it because no corruption has been consumed yet. Instead + * when that happens another machine check will happen. + * + * Handles page cache pages in various states. The tricky part + * here is that we can access any page asynchronous to other VM + * users, because memory failures could happen anytime and anywhere, + * possibly violating some of their assumptions. This is why this code + * has to be extremely careful. Generally it tries to use normal locking + * rules, as in get the standard locks, even if that means the + * error handling takes potentially a long time. + * + * Some of the operations here are somewhat inefficient and have non + * linear algorithmic complexity, because the data structures have not + * been optimized for this case. This is in particular the case + * for the mapping from a vma to a process. Since this case is expected + * to be rare we hope we can get away with this. + +The code consists of a the high level handler in mm/memory-failure.c, +a new page poison bit and various checks in the VM to handle poisoned +pages. + +The main target right now is KVM guests, but it works for all kinds +of applications. KVM support requires a recent qemu-kvm release. + +For the KVM use there was need for a new signal type so that +KVM can inject the machine check into the guest with the proper +address. This in theory allows other applications to handle +memory failures too. The expection is that near all applications +won't do that, but some very specialized ones might. + +--- + +There are two (actually three) modi memory failure recovery can be in: + +vm.memory_failure_recovery sysctl set to zero: + All memory failures cause a panic. Do not attempt recovery. + (on x86 this can be also affected by the tolerant level of the + MCE subsystem) + +early kill + (can be controlled globally and per process) + Send SIGBUS to the application as soon as the error is detected + This allows applications who can process memory errors in a gentle + way (e.g. drop affected object) + This is the mode used by KVM qemu. + +late kill + Send SIGBUS when the application runs into the corrupted page. + This is best for memory error unaware applications and default + Note some pages are always handled as late kill. + +--- + +User control: + +vm.memory_failure_recovery + See sysctl.txt + +vm.memory_failure_early_kill + Enable early kill mode globally + +PR_MCE_KILL + Set early/late kill mode/revert to system default + arg1: PR_MCE_KILL_CLEAR: Revert to system default + arg1: PR_MCE_KILL_SET: arg2 defines thread specific mode + PR_MCE_KILL_EARLY: Early kill + PR_MCE_KILL_LATE: Late kill + PR_MCE_KILL_DEFAULT: Use system global default +PR_MCE_KILL_GET + return current mode + + +--- + +Testing: + +madvise(MADV_POISON, ....) + (as root) + Poison a page in the process for testing + + +hwpoison-inject module through debugfs + /sys/debug/hwpoison/corrupt-pfn + +Inject hwpoison fault at PFN echoed into this file + + +Architecture specific MCE injector + +x86 has mce-inject, mce-test + +Some portable hwpoison test programs in mce-test, see blow. + +--- + +References: + +http://halobates.de/mce-lc09-2.pdf + Overview presentation from LinuxCon 09 + +git://git.kernel.org/pub/scm/utils/cpu/mce/mce-test.git + Test suite (hwpoison specific portable tests in tsrc) + +git://git.kernel.org/pub/scm/utils/cpu/mce/mce-inject.git + x86 specific injector + + +--- + +Limitations: + +- Not all page types are supported and never will. Most kernel internal +objects cannot be recovered, only LRU pages for now. +- Right now hugepage support is missing. + +--- +Andi Kleen, Oct 2009 + |