From c04fc586c1a480ba198f03ae7b6cbd7b57380b91 Mon Sep 17 00:00:00 2001 From: Gary Hade Date: Tue, 6 Jan 2009 14:39:14 -0800 Subject: mm: show node to memory section relationship with symlinks in sysfs Show node to memory section relationship with symlinks in sysfs Add /sys/devices/system/node/nodeX/memoryY symlinks for all the memory sections located on nodeX. For example: /sys/devices/system/node/node1/memory135 -> ../../memory/memory135 indicates that memory section 135 resides on node1. Also revises documentation to cover this change as well as updating Documentation/ABI/testing/sysfs-devices-memory to include descriptions of memory hotremove files 'phys_device', 'phys_index', and 'state' that were previously not described there. In addition to it always being a good policy to provide users with the maximum possible amount of physical location information for resources that can be hot-added and/or hot-removed, the following are some (but likely not all) of the user benefits provided by this change. Immediate: - Provides information needed to determine the specific node on which a defective DIMM is located. This will reduce system downtime when the node or defective DIMM is swapped out. - Prevents unintended onlining of a memory section that was previously offlined due to a defective DIMM. This could happen during node hot-add when the user or node hot-add assist script onlines _all_ offlined sections due to user or script inability to identify the specific memory sections located on the hot-added node. The consequences of reintroducing the defective memory could be ugly. - Provides information needed to vary the amount and distribution of memory on specific nodes for testing or debugging purposes. Future: - Will provide information needed to identify the memory sections that need to be offlined prior to physical removal of a specific node. Symlink creation during boot was tested on 2-node x86_64, 2-node ppc64, and 2-node ia64 systems. Symlink creation during physical memory hot-add tested on a 2-node x86_64 system. Signed-off-by: Gary Hade Signed-off-by: Badari Pulavarty Acked-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/ABI/testing/sysfs-devices-memory | 51 +++++++++++++++++++++++++- 1 file changed, 50 insertions(+), 1 deletion(-) (limited to 'Documentation/ABI') diff --git a/Documentation/ABI/testing/sysfs-devices-memory b/Documentation/ABI/testing/sysfs-devices-memory index 7a16fe1e227..9fe91c02ee4 100644 --- a/Documentation/ABI/testing/sysfs-devices-memory +++ b/Documentation/ABI/testing/sysfs-devices-memory @@ -6,7 +6,6 @@ Description: internal state of the kernel memory blocks. Files could be added or removed dynamically to represent hot-add/remove operations. - Users: hotplug memory add/remove tools https://w3.opensource.ibm.com/projects/powerpc-utils/ @@ -19,6 +18,56 @@ Description: This is useful for a user-level agent to determine identify removable sections of the memory before attempting potentially expensive hot-remove memory operation +Users: hotplug memory remove tools + https://w3.opensource.ibm.com/projects/powerpc-utils/ + +What: /sys/devices/system/memory/memoryX/phys_device +Date: September 2008 +Contact: Badari Pulavarty +Description: + The file /sys/devices/system/memory/memoryX/phys_device + is read-only and is designed to show the name of physical + memory device. Implementation is currently incomplete. +What: /sys/devices/system/memory/memoryX/phys_index +Date: September 2008 +Contact: Badari Pulavarty +Description: + The file /sys/devices/system/memory/memoryX/phys_index + is read-only and contains the section ID in hexadecimal + which is equivalent to decimal X contained in the + memory section directory name. + +What: /sys/devices/system/memory/memoryX/state +Date: September 2008 +Contact: Badari Pulavarty +Description: + The file /sys/devices/system/memory/memoryX/state + is read-write. When read, it's contents show the + online/offline state of the memory section. When written, + root can toggle the the online/offline state of a removable + memory section (see removable file description above) + using the following commands. + # echo online > /sys/devices/system/memory/memoryX/state + # echo offline > /sys/devices/system/memory/memoryX/state + + For example, if /sys/devices/system/memory/memory22/removable + contains a value of 1 and + /sys/devices/system/memory/memory22/state contains the + string "online" the following command can be executed by + by root to offline that section. + # echo offline > /sys/devices/system/memory/memory22/state Users: hotplug memory remove tools https://w3.opensource.ibm.com/projects/powerpc-utils/ + +What: /sys/devices/system/node/nodeX/memoryY +Date: September 2008 +Contact: Gary Hade +Description: + When CONFIG_NUMA is enabled + /sys/devices/system/node/nodeX/memoryY is a symbolic link that + points to the corresponding /sys/devices/system/memory/memoryY + memory section directory. For example, the following symbolic + link is created for memory section 9 on node0. + /sys/devices/system/node/node0/memory9 -> ../../memory/memory9 + -- cgit v1.2.3 From 7ad68e2f970fd84d15ad67ce3216aed05f944a9c Mon Sep 17 00:00:00 2001 From: David Brownell Date: Tue, 11 Nov 2008 17:39:02 -0800 Subject: regulator: sysfs attribute reduction (v2) Clean up the sysfs interface to regulators by only exposing the attributes that can be properly displayed. For example: when a particular regulator method is needed to display the value, only create that attribute when that method exists. This cleaned-up interface is much more comprehensible. Most regulators only support a subset of the possible methods, so often more than half the attributes would be meaningless. Many "not defined" values are no longer necessary. (But handling of out-of-range values still looks a bit iffy.) Documentation is updated to reflect that few of the attributes are *always* present, and to briefly explain why a regulator may not have a given attribute. This adds object code, about a dozen bytes more than was removed by the preceding patch, but saves a bunch of per-regulator data associated with the now-removed attributes. So there's a net reduction in memory footprint. Signed-off-by: David Brownell Signed-off-by: Liam Girdwood --- Documentation/ABI/testing/sysfs-class-regulator | 136 +++++++++++------------- 1 file changed, 60 insertions(+), 76 deletions(-) (limited to 'Documentation/ABI') diff --git a/Documentation/ABI/testing/sysfs-class-regulator b/Documentation/ABI/testing/sysfs-class-regulator index 3731f6f29bc..873ef1fc156 100644 --- a/Documentation/ABI/testing/sysfs-class-regulator +++ b/Documentation/ABI/testing/sysfs-class-regulator @@ -3,8 +3,9 @@ Date: April 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called - state. This holds the regulator output state. + Some regulator directories will contain a field called + state. This reports the regulator enable status, for + regulators which can report that value. This will be one of the following strings: @@ -18,7 +19,8 @@ Description: 'disabled' means the regulator output is OFF and is not supplying power to the system.. - 'unknown' means software cannot determine the state. + 'unknown' means software cannot determine the state, or + the reported state is invalid. NOTE: this field can be used in conjunction with microvolts and microamps to determine regulator output levels. @@ -53,9 +55,10 @@ Date: April 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called microvolts. This holds the regulator output voltage setting - measured in microvolts (i.e. E-6 Volts). + measured in microvolts (i.e. E-6 Volts), for regulators + which can report that voltage. NOTE: This value should not be used to determine the regulator output voltage level as this value is the same regardless of @@ -67,9 +70,10 @@ Date: April 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called microamps. This holds the regulator output current limit - setting measured in microamps (i.e. E-6 Amps). + setting measured in microamps (i.e. E-6 Amps), for regulators + which can report that current. NOTE: This value should not be used to determine the regulator output current level as this value is the same regardless of @@ -81,8 +85,9 @@ Date: April 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called - opmode. This holds the regulator operating mode setting. + Some regulator directories will contain a field called + opmode. This holds the current regulator operating mode, + for regulators which can report it. The opmode value can be one of the following strings: @@ -92,7 +97,7 @@ Description: 'standby' 'unknown' - The modes are described in include/linux/regulator/regulator.h + The modes are described in include/linux/regulator/consumer.h NOTE: This value should not be used to determine the regulator output operating mode as this value is the same regardless of @@ -104,9 +109,10 @@ Date: April 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called min_microvolts. This holds the minimum safe working regulator - output voltage setting for this domain measured in microvolts. + output voltage setting for this domain measured in microvolts, + for regulators which support voltage constraints. NOTE: this will return the string 'constraint not defined' if the power domain has no min microvolts constraint defined by @@ -118,9 +124,10 @@ Date: April 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called max_microvolts. This holds the maximum safe working regulator - output voltage setting for this domain measured in microvolts. + output voltage setting for this domain measured in microvolts, + for regulators which support voltage constraints. NOTE: this will return the string 'constraint not defined' if the power domain has no max microvolts constraint defined by @@ -132,10 +139,10 @@ Date: April 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called min_microamps. This holds the minimum safe working regulator output current limit setting for this domain measured in - microamps. + microamps, for regulators which support current constraints. NOTE: this will return the string 'constraint not defined' if the power domain has no min microamps constraint defined by @@ -147,10 +154,10 @@ Date: April 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called max_microamps. This holds the maximum safe working regulator output current limit setting for this domain measured in - microamps. + microamps, for regulators which support current constraints. NOTE: this will return the string 'constraint not defined' if the power domain has no max microamps constraint defined by @@ -185,7 +192,7 @@ Date: April 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called requested_microamps. This holds the total requested load current in microamps for this regulator from all its consumer devices. @@ -204,125 +211,102 @@ Date: May 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called suspend_mem_microvolts. This holds the regulator output voltage setting for this domain measured in microvolts when - the system is suspended to memory. - - NOTE: this will return the string 'not defined' if - the power domain has no suspend to memory voltage defined by - platform code. + the system is suspended to memory, for voltage regulators + implementing suspend voltage configuration constraints. What: /sys/class/regulator/.../suspend_disk_microvolts Date: May 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called suspend_disk_microvolts. This holds the regulator output voltage setting for this domain measured in microvolts when - the system is suspended to disk. - - NOTE: this will return the string 'not defined' if - the power domain has no suspend to disk voltage defined by - platform code. + the system is suspended to disk, for voltage regulators + implementing suspend voltage configuration constraints. What: /sys/class/regulator/.../suspend_standby_microvolts Date: May 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called suspend_standby_microvolts. This holds the regulator output voltage setting for this domain measured in microvolts when - the system is suspended to standby. - - NOTE: this will return the string 'not defined' if - the power domain has no suspend to standby voltage defined by - platform code. + the system is suspended to standby, for voltage regulators + implementing suspend voltage configuration constraints. What: /sys/class/regulator/.../suspend_mem_mode Date: May 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called suspend_mem_mode. This holds the regulator operating mode setting for this domain when the system is suspended to - memory. - - NOTE: this will return the string 'not defined' if - the power domain has no suspend to memory mode defined by - platform code. + memory, for regulators implementing suspend mode + configuration constraints. What: /sys/class/regulator/.../suspend_disk_mode Date: May 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called suspend_disk_mode. This holds the regulator operating mode - setting for this domain when the system is suspended to disk. - - NOTE: this will return the string 'not defined' if - the power domain has no suspend to disk mode defined by - platform code. + setting for this domain when the system is suspended to disk, + for regulators implementing suspend mode configuration + constraints. What: /sys/class/regulator/.../suspend_standby_mode Date: May 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called suspend_standby_mode. This holds the regulator operating mode setting for this domain when the system is suspended to - standby. - - NOTE: this will return the string 'not defined' if - the power domain has no suspend to standby mode defined by - platform code. + standby, for regulators implementing suspend mode + configuration constraints. What: /sys/class/regulator/.../suspend_mem_state Date: May 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called suspend_mem_state. This holds the regulator operating state - when suspended to memory. - - This will be one of the following strings: + when suspended to memory, for regulators implementing suspend + configuration constraints. - 'enabled' - 'disabled' - 'not defined' + This will be one of the same strings reported by + the "state" attribute. What: /sys/class/regulator/.../suspend_disk_state Date: May 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called suspend_disk_state. This holds the regulator operating state - when suspended to disk. - - This will be one of the following strings: + when suspended to disk, for regulators implementing + suspend configuration constraints. - 'enabled' - 'disabled' - 'not defined' + This will be one of the same strings reported by + the "state" attribute. What: /sys/class/regulator/.../suspend_standby_state Date: May 2008 KernelVersion: 2.6.26 Contact: Liam Girdwood Description: - Each regulator directory will contain a field called + Some regulator directories will contain a field called suspend_standby_state. This holds the regulator operating - state when suspended to standby. - - This will be one of the following strings: + state when suspended to standby, for regulators implementing + suspend configuration constraints. - 'enabled' - 'disabled' - 'not defined' + This will be one of the same strings reported by + the "state" attribute. -- cgit v1.2.3