Loading Documentation/ABI/testing/sysfs-kernel-slab 0 → 100644 +479 −0 Original line number Diff line number Diff line What: /sys/kernel/slab Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The /sys/kernel/slab directory contains a snapshot of the internal state of the SLUB allocator for each cache. Certain files may be modified to change the behavior of the cache (and any cache it aliases, if any). Users: kernel memory tuning tools What: /sys/kernel/slab/cache/aliases Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The aliases file is read-only and specifies how many caches have merged into this cache. What: /sys/kernel/slab/cache/align Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The align file is read-only and specifies the cache's object alignment in bytes. What: /sys/kernel/slab/cache/alloc_calls Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The alloc_calls file is read-only and lists the kernel code locations from which allocations for this cache were performed. The alloc_calls file only contains information if debugging is enabled for that cache (see Documentation/vm/slub.txt). What: /sys/kernel/slab/cache/alloc_fastpath Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The alloc_fastpath file is read-only and specifies how many objects have been allocated using the fast path. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/alloc_from_partial Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The alloc_from_partial file is read-only and specifies how many times a cpu slab has been full and it has been refilled by using a slab from the list of partially used slabs. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/alloc_refill Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The alloc_refill file is read-only and specifies how many times the per-cpu freelist was empty but there were objects available as the result of remote cpu frees. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/alloc_slab Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The alloc_slab file is read-only and specifies how many times a new slab had to be allocated from the page allocator. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/alloc_slowpath Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The alloc_slowpath file is read-only and specifies how many objects have been allocated using the slow path because of a refill or allocation from a partial or new slab. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/cache_dma Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The cache_dma file is read-only and specifies whether objects are from ZONE_DMA. Available when CONFIG_ZONE_DMA is enabled. What: /sys/kernel/slab/cache/cpu_slabs Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The cpu_slabs file is read-only and displays how many cpu slabs are active and their NUMA locality. What: /sys/kernel/slab/cache/cpuslab_flush Date: April 2009 KernelVersion: 2.6.31 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file cpuslab_flush is read-only and specifies how many times a cache's cpu slabs have been flushed as the result of destroying or shrinking a cache, a cpu going offline, or as the result of forcing an allocation from a certain node. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/ctor Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The ctor file is read-only and specifies the cache's object constructor function, which is invoked for each object when a new slab is allocated. What: /sys/kernel/slab/cache/deactivate_empty Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file deactivate_empty is read-only and specifies how many times an empty cpu slab was deactivated. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/deactivate_full Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file deactivate_full is read-only and specifies how many times a full cpu slab was deactivated. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/deactivate_remote_frees Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file deactivate_remote_frees is read-only and specifies how many times a cpu slab has been deactivated and contained free objects that were freed remotely. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/deactivate_to_head Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file deactivate_to_head is read-only and specifies how many times a partial cpu slab was deactivated and added to the head of its node's partial list. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/deactivate_to_tail Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file deactivate_to_tail is read-only and specifies how many times a partial cpu slab was deactivated and added to the tail of its node's partial list. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/destroy_by_rcu Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The destroy_by_rcu file is read-only and specifies whether slabs (not objects) are freed by rcu. What: /sys/kernel/slab/cache/free_add_partial Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file free_add_partial is read-only and specifies how many times an object has been freed in a full slab so that it had to added to its node's partial list. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/free_calls Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The free_calls file is read-only and lists the locations of object frees if slab debugging is enabled (see Documentation/vm/slub.txt). What: /sys/kernel/slab/cache/free_fastpath Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The free_fastpath file is read-only and specifies how many objects have been freed using the fast path because it was an object from the cpu slab. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/free_frozen Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The free_frozen file is read-only and specifies how many objects have been freed to a frozen slab (i.e. a remote cpu slab). Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/free_remove_partial Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file free_remove_partial is read-only and specifies how many times an object has been freed to a now-empty slab so that it had to be removed from its node's partial list. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/free_slab Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The free_slab file is read-only and specifies how many times an empty slab has been freed back to the page allocator. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/free_slowpath Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The free_slowpath file is read-only and specifies how many objects have been freed using the slow path (i.e. to a full or partial slab). Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/hwcache_align Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The hwcache_align file is read-only and specifies whether objects are aligned on cachelines. What: /sys/kernel/slab/cache/min_partial Date: February 2009 KernelVersion: 2.6.30 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, David Rientjes <rientjes@google.com> Description: The min_partial file specifies how many empty slabs shall remain on a node's partial list to avoid the overhead of allocating new slabs. Such slabs may be reclaimed by utilizing the shrink file. What: /sys/kernel/slab/cache/object_size Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The object_size file is read-only and specifies the cache's object size. What: /sys/kernel/slab/cache/objects Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The objects file is read-only and displays how many objects are active and from which nodes they are from. What: /sys/kernel/slab/cache/objects_partial Date: April 2008 KernelVersion: 2.6.26 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The objects_partial file is read-only and displays how many objects are on partial slabs and from which nodes they are from. What: /sys/kernel/slab/cache/objs_per_slab Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file objs_per_slab is read-only and specifies how many objects may be allocated from a single slab of the order specified in /sys/kernel/slab/cache/order. What: /sys/kernel/slab/cache/order Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The order file specifies the page order at which new slabs are allocated. It is writable and can be changed to increase the number of objects per slab. If a slab cannot be allocated because of fragmentation, SLUB will retry with the minimum order possible depending on its characteristics. What: /sys/kernel/slab/cache/order_fallback Date: April 2008 KernelVersion: 2.6.26 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file order_fallback is read-only and specifies how many times an allocation of a new slab has not been possible at the cache's order and instead fallen back to its minimum possible order. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/partial Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The partial file is read-only and displays how long many partial slabs there are and how long each node's list is. What: /sys/kernel/slab/cache/poison Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The poison file specifies whether objects should be poisoned when a new slab is allocated. What: /sys/kernel/slab/cache/reclaim_account Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The reclaim_account file specifies whether the cache's objects are reclaimable (and grouped by their mobility). What: /sys/kernel/slab/cache/red_zone Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The red_zone file specifies whether the cache's objects are red zoned. What: /sys/kernel/slab/cache/remote_node_defrag_ratio Date: January 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file remote_node_defrag_ratio specifies the percentage of times SLUB will attempt to refill the cpu slab with a partial slab from a remote node as opposed to allocating a new slab on the local node. This reduces the amount of wasted memory over the entire system but can be expensive. Available when CONFIG_NUMA is enabled. What: /sys/kernel/slab/cache/sanity_checks Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The sanity_checks file specifies whether expensive checks should be performed on free and, at minimum, enables double free checks. Caches that enable sanity_checks cannot be merged with caches that do not. What: /sys/kernel/slab/cache/shrink Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The shrink file is written when memory should be reclaimed from a cache. Empty partial slabs are freed and the partial list is sorted so the slabs with the fewest available objects are used first. What: /sys/kernel/slab/cache/slab_size Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The slab_size file is read-only and specifies the object size with metadata (debugging information and alignment) in bytes. What: /sys/kernel/slab/cache/slabs Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The slabs file is read-only and displays how long many slabs there are (both cpu and partial) and from which nodes they are from. What: /sys/kernel/slab/cache/store_user Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The store_user file specifies whether the location of allocation or free should be tracked for a cache. What: /sys/kernel/slab/cache/total_objects Date: April 2008 KernelVersion: 2.6.26 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The total_objects file is read-only and displays how many total objects a cache has and from which nodes they are from. What: /sys/kernel/slab/cache/trace Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The trace file specifies whether object allocations and frees should be traced. What: /sys/kernel/slab/cache/validate Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: Writing to the validate file causes SLUB to traverse all of its cache's objects and check the validity of metadata. Documentation/DocBook/kgdb.tmpl +1 −1 Original line number Diff line number Diff line Loading @@ -281,7 +281,7 @@ seriously wrong while debugging, it will most often be the case that you want to enable gdb to be verbose about its target communications. You do this prior to issuing the <constant>target remote</constant> command by typing in: <constant>set remote debug 1</constant> remote</constant> command by typing in: <constant>set debug remote 1</constant> </para> </chapter> <chapter id="KGDBTestSuite"> Loading Documentation/filesystems/tmpfs.txt +1 −1 Original line number Diff line number Diff line Loading @@ -133,4 +133,4 @@ RAM/SWAP in 10240 inodes and it is only accessible by root. Author: Christoph Rohland <cr@sap.com>, 1.12.01 Updated: Hugh Dickins <hugh@veritas.com>, 4 June 2007 Hugh Dickins, 4 June 2007 Documentation/input/multi-touch-protocol.txt +79 −24 Original line number Diff line number Diff line Loading @@ -18,8 +18,12 @@ Usage Anonymous finger details are sent sequentially as separate packets of ABS events. Only the ABS_MT events are recognized as part of a finger packet. The end of a packet is marked by calling the input_mt_sync() function, which generates a SYN_MT_REPORT event. The end of multi-touch transfer is marked by calling the usual input_sync() function. function, which generates a SYN_MT_REPORT event. This instructs the receiver to accept the data for the current finger and prepare to receive another. The end of a multi-touch transfer is marked by calling the usual input_sync() function. This instructs the receiver to act upon events accumulated since last EV_SYN/SYN_REPORT and prepare to receive a new set of events/packets. A set of ABS_MT events with the desired properties is defined. The events are divided into categories, to allow for partial implementation. The Loading @@ -27,11 +31,26 @@ minimum set consists of ABS_MT_TOUCH_MAJOR, ABS_MT_POSITION_X and ABS_MT_POSITION_Y, which allows for multiple fingers to be tracked. If the device supports it, the ABS_MT_WIDTH_MAJOR may be used to provide the size of the approaching finger. Anisotropy and direction may be specified with ABS_MT_TOUCH_MINOR, ABS_MT_WIDTH_MINOR and ABS_MT_ORIENTATION. Devices with more granular information may specify general shapes as blobs, i.e., as a sequence of rectangular shapes grouped together by an ABS_MT_BLOB_ID. Finally, the ABS_MT_TOOL_TYPE may be used to specify whether the touching tool is a finger or a pen or something else. ABS_MT_TOUCH_MINOR, ABS_MT_WIDTH_MINOR and ABS_MT_ORIENTATION. The ABS_MT_TOOL_TYPE may be used to specify whether the touching tool is a finger or a pen or something else. Devices with more granular information may specify general shapes as blobs, i.e., as a sequence of rectangular shapes grouped together by an ABS_MT_BLOB_ID. Finally, for the few devices that currently support it, the ABS_MT_TRACKING_ID event may be used to report finger tracking from hardware [5]. Here is what a minimal event sequence for a two-finger touch would look like: ABS_MT_TOUCH_MAJOR ABS_MT_POSITION_X ABS_MT_POSITION_Y SYN_MT_REPORT ABS_MT_TOUCH_MAJOR ABS_MT_POSITION_X ABS_MT_POSITION_Y SYN_MT_REPORT SYN_REPORT Event Semantics Loading @@ -44,24 +63,24 @@ ABS_MT_TOUCH_MAJOR The length of the major axis of the contact. The length should be given in surface units. If the surface has an X times Y resolution, the largest possible value of ABS_MT_TOUCH_MAJOR is sqrt(X^2 + Y^2), the diagonal. possible value of ABS_MT_TOUCH_MAJOR is sqrt(X^2 + Y^2), the diagonal [4]. ABS_MT_TOUCH_MINOR The length, in surface units, of the minor axis of the contact. If the contact is circular, this event can be omitted. contact is circular, this event can be omitted [4]. ABS_MT_WIDTH_MAJOR The length, in surface units, of the major axis of the approaching tool. This should be understood as the size of the tool itself. The orientation of the contact and the approaching tool are assumed to be the same. same [4]. ABS_MT_WIDTH_MINOR The length, in surface units, of the minor axis of the approaching tool. Omit if circular. tool. Omit if circular [4]. The above four values can be used to derive additional information about the contact. The ratio ABS_MT_TOUCH_MAJOR / ABS_MT_WIDTH_MAJOR approximates Loading @@ -70,14 +89,17 @@ different characteristic widths [1]. ABS_MT_ORIENTATION The orientation of the ellipse. The value should describe half a revolution clockwise around the touch center. The scale of the value is arbitrary, but zero should be returned for an ellipse aligned along the Y axis of the surface. As an example, an index finger placed straight onto the axis could return zero orientation, something negative when twisted to the left, and something positive when twisted to the right. This value can be omitted if the touching object is circular, or if the information is not available in the kernel driver. The orientation of the ellipse. The value should describe a signed quarter of a revolution clockwise around the touch center. The signed value range is arbitrary, but zero should be returned for a finger aligned along the Y axis of the surface, a negative value when finger is turned to the left, and a positive value when finger turned to the right. When completely aligned with the X axis, the range max should be returned. Orientation can be omitted if the touching object is circular, or if the information is not available in the kernel driver. Partial orientation support is possible if the device can distinguish between the two axis, but not (uniquely) any values in between. In such cases, the range of ABS_MT_ORIENTATION should be [0, 1] [4]. ABS_MT_POSITION_X Loading @@ -98,8 +120,35 @@ ABS_MT_BLOB_ID The BLOB_ID groups several packets together into one arbitrarily shaped contact. This is a low-level anonymous grouping, and should not be confused with the high-level contactID, explained below. Most kernel drivers will not have this capability, and can safely omit the event. with the high-level trackingID [5]. Most kernel drivers will not have blob capability, and can safely omit the event. ABS_MT_TRACKING_ID The TRACKING_ID identifies an initiated contact throughout its life cycle [5]. There are currently only a few devices that support it, so this event should normally be omitted. Event Computation ----------------- The flora of different hardware unavoidably leads to some devices fitting better to the MT protocol than others. To simplify and unify the mapping, this section gives recipes for how to compute certain events. For devices reporting contacts as rectangular shapes, signed orientation cannot be obtained. Assuming X and Y are the lengths of the sides of the touching rectangle, here is a simple formula that retains the most information possible: ABS_MT_TOUCH_MAJOR := max(X, Y) ABS_MT_TOUCH_MINOR := min(X, Y) ABS_MT_ORIENTATION := bool(X > Y) The range of ABS_MT_ORIENTATION should be set to [0, 1], to indicate that the device can distinguish between a finger along the Y axis (0) and a finger along the X axis (1). Finger Tracking Loading @@ -109,14 +158,18 @@ The kernel driver should generate an arbitrary enumeration of the set of anonymous contacts currently on the surface. The order in which the packets appear in the event stream is not important. The process of finger tracking, i.e., to assign a unique contactID to each The process of finger tracking, i.e., to assign a unique trackingID to each initiated contact on the surface, is left to user space; preferably the multi-touch X driver [3]. In that driver, the contactID stays the same and multi-touch X driver [3]. In that driver, the trackingID stays the same and unique until the contact vanishes (when the finger leaves the surface). The problem of assigning a set of anonymous fingers to a set of identified fingers is a euclidian bipartite matching problem at each event update, and relies on a sufficiently rapid update rate. There are a few devices that support trackingID in hardware. User space can make use of these native identifiers to reduce bandwidth and cpu usage. Notes ----- Loading @@ -136,5 +189,7 @@ could be used to derive tilt. time of writing (April 2009), the MT protocol is not yet merged, and the prototype implements finger matching, basic mouse support and two-finger scrolling. The project aims at improving the quality of current multi-touch functionality available in the synaptics X driver, and in addition functionality available in the Synaptics X driver, and in addition implement more advanced gestures. [4] See the section on event computation. [5] See the section on finger tracking. Documentation/kernel-parameters.txt +4 −0 File changed.Preview size limit exceeded, changes collapsed. Show changes Loading
Documentation/ABI/testing/sysfs-kernel-slab 0 → 100644 +479 −0 Original line number Diff line number Diff line What: /sys/kernel/slab Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The /sys/kernel/slab directory contains a snapshot of the internal state of the SLUB allocator for each cache. Certain files may be modified to change the behavior of the cache (and any cache it aliases, if any). Users: kernel memory tuning tools What: /sys/kernel/slab/cache/aliases Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The aliases file is read-only and specifies how many caches have merged into this cache. What: /sys/kernel/slab/cache/align Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The align file is read-only and specifies the cache's object alignment in bytes. What: /sys/kernel/slab/cache/alloc_calls Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The alloc_calls file is read-only and lists the kernel code locations from which allocations for this cache were performed. The alloc_calls file only contains information if debugging is enabled for that cache (see Documentation/vm/slub.txt). What: /sys/kernel/slab/cache/alloc_fastpath Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The alloc_fastpath file is read-only and specifies how many objects have been allocated using the fast path. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/alloc_from_partial Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The alloc_from_partial file is read-only and specifies how many times a cpu slab has been full and it has been refilled by using a slab from the list of partially used slabs. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/alloc_refill Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The alloc_refill file is read-only and specifies how many times the per-cpu freelist was empty but there were objects available as the result of remote cpu frees. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/alloc_slab Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The alloc_slab file is read-only and specifies how many times a new slab had to be allocated from the page allocator. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/alloc_slowpath Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The alloc_slowpath file is read-only and specifies how many objects have been allocated using the slow path because of a refill or allocation from a partial or new slab. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/cache_dma Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The cache_dma file is read-only and specifies whether objects are from ZONE_DMA. Available when CONFIG_ZONE_DMA is enabled. What: /sys/kernel/slab/cache/cpu_slabs Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The cpu_slabs file is read-only and displays how many cpu slabs are active and their NUMA locality. What: /sys/kernel/slab/cache/cpuslab_flush Date: April 2009 KernelVersion: 2.6.31 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file cpuslab_flush is read-only and specifies how many times a cache's cpu slabs have been flushed as the result of destroying or shrinking a cache, a cpu going offline, or as the result of forcing an allocation from a certain node. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/ctor Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The ctor file is read-only and specifies the cache's object constructor function, which is invoked for each object when a new slab is allocated. What: /sys/kernel/slab/cache/deactivate_empty Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file deactivate_empty is read-only and specifies how many times an empty cpu slab was deactivated. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/deactivate_full Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file deactivate_full is read-only and specifies how many times a full cpu slab was deactivated. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/deactivate_remote_frees Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file deactivate_remote_frees is read-only and specifies how many times a cpu slab has been deactivated and contained free objects that were freed remotely. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/deactivate_to_head Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file deactivate_to_head is read-only and specifies how many times a partial cpu slab was deactivated and added to the head of its node's partial list. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/deactivate_to_tail Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file deactivate_to_tail is read-only and specifies how many times a partial cpu slab was deactivated and added to the tail of its node's partial list. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/destroy_by_rcu Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The destroy_by_rcu file is read-only and specifies whether slabs (not objects) are freed by rcu. What: /sys/kernel/slab/cache/free_add_partial Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file free_add_partial is read-only and specifies how many times an object has been freed in a full slab so that it had to added to its node's partial list. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/free_calls Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The free_calls file is read-only and lists the locations of object frees if slab debugging is enabled (see Documentation/vm/slub.txt). What: /sys/kernel/slab/cache/free_fastpath Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The free_fastpath file is read-only and specifies how many objects have been freed using the fast path because it was an object from the cpu slab. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/free_frozen Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The free_frozen file is read-only and specifies how many objects have been freed to a frozen slab (i.e. a remote cpu slab). Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/free_remove_partial Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file free_remove_partial is read-only and specifies how many times an object has been freed to a now-empty slab so that it had to be removed from its node's partial list. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/free_slab Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The free_slab file is read-only and specifies how many times an empty slab has been freed back to the page allocator. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/free_slowpath Date: February 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The free_slowpath file is read-only and specifies how many objects have been freed using the slow path (i.e. to a full or partial slab). Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/hwcache_align Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The hwcache_align file is read-only and specifies whether objects are aligned on cachelines. What: /sys/kernel/slab/cache/min_partial Date: February 2009 KernelVersion: 2.6.30 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, David Rientjes <rientjes@google.com> Description: The min_partial file specifies how many empty slabs shall remain on a node's partial list to avoid the overhead of allocating new slabs. Such slabs may be reclaimed by utilizing the shrink file. What: /sys/kernel/slab/cache/object_size Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The object_size file is read-only and specifies the cache's object size. What: /sys/kernel/slab/cache/objects Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The objects file is read-only and displays how many objects are active and from which nodes they are from. What: /sys/kernel/slab/cache/objects_partial Date: April 2008 KernelVersion: 2.6.26 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The objects_partial file is read-only and displays how many objects are on partial slabs and from which nodes they are from. What: /sys/kernel/slab/cache/objs_per_slab Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file objs_per_slab is read-only and specifies how many objects may be allocated from a single slab of the order specified in /sys/kernel/slab/cache/order. What: /sys/kernel/slab/cache/order Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The order file specifies the page order at which new slabs are allocated. It is writable and can be changed to increase the number of objects per slab. If a slab cannot be allocated because of fragmentation, SLUB will retry with the minimum order possible depending on its characteristics. What: /sys/kernel/slab/cache/order_fallback Date: April 2008 KernelVersion: 2.6.26 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file order_fallback is read-only and specifies how many times an allocation of a new slab has not been possible at the cache's order and instead fallen back to its minimum possible order. Available when CONFIG_SLUB_STATS is enabled. What: /sys/kernel/slab/cache/partial Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The partial file is read-only and displays how long many partial slabs there are and how long each node's list is. What: /sys/kernel/slab/cache/poison Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The poison file specifies whether objects should be poisoned when a new slab is allocated. What: /sys/kernel/slab/cache/reclaim_account Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The reclaim_account file specifies whether the cache's objects are reclaimable (and grouped by their mobility). What: /sys/kernel/slab/cache/red_zone Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The red_zone file specifies whether the cache's objects are red zoned. What: /sys/kernel/slab/cache/remote_node_defrag_ratio Date: January 2008 KernelVersion: 2.6.25 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The file remote_node_defrag_ratio specifies the percentage of times SLUB will attempt to refill the cpu slab with a partial slab from a remote node as opposed to allocating a new slab on the local node. This reduces the amount of wasted memory over the entire system but can be expensive. Available when CONFIG_NUMA is enabled. What: /sys/kernel/slab/cache/sanity_checks Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The sanity_checks file specifies whether expensive checks should be performed on free and, at minimum, enables double free checks. Caches that enable sanity_checks cannot be merged with caches that do not. What: /sys/kernel/slab/cache/shrink Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The shrink file is written when memory should be reclaimed from a cache. Empty partial slabs are freed and the partial list is sorted so the slabs with the fewest available objects are used first. What: /sys/kernel/slab/cache/slab_size Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The slab_size file is read-only and specifies the object size with metadata (debugging information and alignment) in bytes. What: /sys/kernel/slab/cache/slabs Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The slabs file is read-only and displays how long many slabs there are (both cpu and partial) and from which nodes they are from. What: /sys/kernel/slab/cache/store_user Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The store_user file specifies whether the location of allocation or free should be tracked for a cache. What: /sys/kernel/slab/cache/total_objects Date: April 2008 KernelVersion: 2.6.26 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The total_objects file is read-only and displays how many total objects a cache has and from which nodes they are from. What: /sys/kernel/slab/cache/trace Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: The trace file specifies whether object allocations and frees should be traced. What: /sys/kernel/slab/cache/validate Date: May 2007 KernelVersion: 2.6.22 Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Christoph Lameter <cl@linux-foundation.org> Description: Writing to the validate file causes SLUB to traverse all of its cache's objects and check the validity of metadata.
Documentation/DocBook/kgdb.tmpl +1 −1 Original line number Diff line number Diff line Loading @@ -281,7 +281,7 @@ seriously wrong while debugging, it will most often be the case that you want to enable gdb to be verbose about its target communications. You do this prior to issuing the <constant>target remote</constant> command by typing in: <constant>set remote debug 1</constant> remote</constant> command by typing in: <constant>set debug remote 1</constant> </para> </chapter> <chapter id="KGDBTestSuite"> Loading
Documentation/filesystems/tmpfs.txt +1 −1 Original line number Diff line number Diff line Loading @@ -133,4 +133,4 @@ RAM/SWAP in 10240 inodes and it is only accessible by root. Author: Christoph Rohland <cr@sap.com>, 1.12.01 Updated: Hugh Dickins <hugh@veritas.com>, 4 June 2007 Hugh Dickins, 4 June 2007
Documentation/input/multi-touch-protocol.txt +79 −24 Original line number Diff line number Diff line Loading @@ -18,8 +18,12 @@ Usage Anonymous finger details are sent sequentially as separate packets of ABS events. Only the ABS_MT events are recognized as part of a finger packet. The end of a packet is marked by calling the input_mt_sync() function, which generates a SYN_MT_REPORT event. The end of multi-touch transfer is marked by calling the usual input_sync() function. function, which generates a SYN_MT_REPORT event. This instructs the receiver to accept the data for the current finger and prepare to receive another. The end of a multi-touch transfer is marked by calling the usual input_sync() function. This instructs the receiver to act upon events accumulated since last EV_SYN/SYN_REPORT and prepare to receive a new set of events/packets. A set of ABS_MT events with the desired properties is defined. The events are divided into categories, to allow for partial implementation. The Loading @@ -27,11 +31,26 @@ minimum set consists of ABS_MT_TOUCH_MAJOR, ABS_MT_POSITION_X and ABS_MT_POSITION_Y, which allows for multiple fingers to be tracked. If the device supports it, the ABS_MT_WIDTH_MAJOR may be used to provide the size of the approaching finger. Anisotropy and direction may be specified with ABS_MT_TOUCH_MINOR, ABS_MT_WIDTH_MINOR and ABS_MT_ORIENTATION. Devices with more granular information may specify general shapes as blobs, i.e., as a sequence of rectangular shapes grouped together by an ABS_MT_BLOB_ID. Finally, the ABS_MT_TOOL_TYPE may be used to specify whether the touching tool is a finger or a pen or something else. ABS_MT_TOUCH_MINOR, ABS_MT_WIDTH_MINOR and ABS_MT_ORIENTATION. The ABS_MT_TOOL_TYPE may be used to specify whether the touching tool is a finger or a pen or something else. Devices with more granular information may specify general shapes as blobs, i.e., as a sequence of rectangular shapes grouped together by an ABS_MT_BLOB_ID. Finally, for the few devices that currently support it, the ABS_MT_TRACKING_ID event may be used to report finger tracking from hardware [5]. Here is what a minimal event sequence for a two-finger touch would look like: ABS_MT_TOUCH_MAJOR ABS_MT_POSITION_X ABS_MT_POSITION_Y SYN_MT_REPORT ABS_MT_TOUCH_MAJOR ABS_MT_POSITION_X ABS_MT_POSITION_Y SYN_MT_REPORT SYN_REPORT Event Semantics Loading @@ -44,24 +63,24 @@ ABS_MT_TOUCH_MAJOR The length of the major axis of the contact. The length should be given in surface units. If the surface has an X times Y resolution, the largest possible value of ABS_MT_TOUCH_MAJOR is sqrt(X^2 + Y^2), the diagonal. possible value of ABS_MT_TOUCH_MAJOR is sqrt(X^2 + Y^2), the diagonal [4]. ABS_MT_TOUCH_MINOR The length, in surface units, of the minor axis of the contact. If the contact is circular, this event can be omitted. contact is circular, this event can be omitted [4]. ABS_MT_WIDTH_MAJOR The length, in surface units, of the major axis of the approaching tool. This should be understood as the size of the tool itself. The orientation of the contact and the approaching tool are assumed to be the same. same [4]. ABS_MT_WIDTH_MINOR The length, in surface units, of the minor axis of the approaching tool. Omit if circular. tool. Omit if circular [4]. The above four values can be used to derive additional information about the contact. The ratio ABS_MT_TOUCH_MAJOR / ABS_MT_WIDTH_MAJOR approximates Loading @@ -70,14 +89,17 @@ different characteristic widths [1]. ABS_MT_ORIENTATION The orientation of the ellipse. The value should describe half a revolution clockwise around the touch center. The scale of the value is arbitrary, but zero should be returned for an ellipse aligned along the Y axis of the surface. As an example, an index finger placed straight onto the axis could return zero orientation, something negative when twisted to the left, and something positive when twisted to the right. This value can be omitted if the touching object is circular, or if the information is not available in the kernel driver. The orientation of the ellipse. The value should describe a signed quarter of a revolution clockwise around the touch center. The signed value range is arbitrary, but zero should be returned for a finger aligned along the Y axis of the surface, a negative value when finger is turned to the left, and a positive value when finger turned to the right. When completely aligned with the X axis, the range max should be returned. Orientation can be omitted if the touching object is circular, or if the information is not available in the kernel driver. Partial orientation support is possible if the device can distinguish between the two axis, but not (uniquely) any values in between. In such cases, the range of ABS_MT_ORIENTATION should be [0, 1] [4]. ABS_MT_POSITION_X Loading @@ -98,8 +120,35 @@ ABS_MT_BLOB_ID The BLOB_ID groups several packets together into one arbitrarily shaped contact. This is a low-level anonymous grouping, and should not be confused with the high-level contactID, explained below. Most kernel drivers will not have this capability, and can safely omit the event. with the high-level trackingID [5]. Most kernel drivers will not have blob capability, and can safely omit the event. ABS_MT_TRACKING_ID The TRACKING_ID identifies an initiated contact throughout its life cycle [5]. There are currently only a few devices that support it, so this event should normally be omitted. Event Computation ----------------- The flora of different hardware unavoidably leads to some devices fitting better to the MT protocol than others. To simplify and unify the mapping, this section gives recipes for how to compute certain events. For devices reporting contacts as rectangular shapes, signed orientation cannot be obtained. Assuming X and Y are the lengths of the sides of the touching rectangle, here is a simple formula that retains the most information possible: ABS_MT_TOUCH_MAJOR := max(X, Y) ABS_MT_TOUCH_MINOR := min(X, Y) ABS_MT_ORIENTATION := bool(X > Y) The range of ABS_MT_ORIENTATION should be set to [0, 1], to indicate that the device can distinguish between a finger along the Y axis (0) and a finger along the X axis (1). Finger Tracking Loading @@ -109,14 +158,18 @@ The kernel driver should generate an arbitrary enumeration of the set of anonymous contacts currently on the surface. The order in which the packets appear in the event stream is not important. The process of finger tracking, i.e., to assign a unique contactID to each The process of finger tracking, i.e., to assign a unique trackingID to each initiated contact on the surface, is left to user space; preferably the multi-touch X driver [3]. In that driver, the contactID stays the same and multi-touch X driver [3]. In that driver, the trackingID stays the same and unique until the contact vanishes (when the finger leaves the surface). The problem of assigning a set of anonymous fingers to a set of identified fingers is a euclidian bipartite matching problem at each event update, and relies on a sufficiently rapid update rate. There are a few devices that support trackingID in hardware. User space can make use of these native identifiers to reduce bandwidth and cpu usage. Notes ----- Loading @@ -136,5 +189,7 @@ could be used to derive tilt. time of writing (April 2009), the MT protocol is not yet merged, and the prototype implements finger matching, basic mouse support and two-finger scrolling. The project aims at improving the quality of current multi-touch functionality available in the synaptics X driver, and in addition functionality available in the Synaptics X driver, and in addition implement more advanced gestures. [4] See the section on event computation. [5] See the section on finger tracking.
Documentation/kernel-parameters.txt +4 −0 File changed.Preview size limit exceeded, changes collapsed. Show changes
