diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-class-bdi | 46 | ||||
| -rw-r--r-- | Documentation/DocBook/Makefile | 2 | ||||
| -rw-r--r-- | Documentation/DocBook/debugobjects.tmpl | 391 | ||||
| -rw-r--r-- | Documentation/DocBook/rapidio.tmpl | 1 | ||||
| -rw-r--r-- | Documentation/braille-console.txt | 34 | ||||
| -rw-r--r-- | Documentation/feature-removal-schedule.txt | 18 | ||||
| -rw-r--r-- | Documentation/filesystems/proc.txt | 21 | ||||
| -rw-r--r-- | Documentation/kernel-parameters.txt | 7 | ||||
| -rw-r--r-- | Documentation/powerpc/mpc52xx-device-tree-bindings.txt | 12 |
9 files changed, 526 insertions, 6 deletions
diff --git a/Documentation/ABI/testing/sysfs-class-bdi b/Documentation/ABI/testing/sysfs-class-bdi new file mode 100644 index 00000000000..5ac1e01bbd4 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-class-bdi @@ -0,0 +1,46 @@ +What: /sys/class/bdi/<bdi>/ +Date: January 2008 +Contact: Peter Zijlstra <a.p.zijlstra@chello.nl> +Description: + +Provide a place in sysfs for the backing_dev_info object. This allows +setting and retrieving various BDI specific variables. + +The <bdi> identifier can be either of the following: + +MAJOR:MINOR + + Device number for block devices, or value of st_dev on + non-block filesystems which provide their own BDI, such as NFS + and FUSE. + +default + + The default backing dev, used for non-block device backed + filesystems which do not provide their own BDI. + +Files under /sys/class/bdi/<bdi>/ +--------------------------------- + +read_ahead_kb (read-write) + + Size of the read-ahead window in kilobytes + +min_ratio (read-write) + + Under normal circumstances each device is given a part of the + total write-back cache that relates to its current average + writeout speed in relation to the other devices. + + The 'min_ratio' parameter allows assigning a minimum + percentage of the write-back cache to a particular device. + For example, this is useful for providing a minimum QoS. + +max_ratio (read-write) + + Allows limiting a particular device to use not more than the + given percentage of the write-back cache. This is useful in + situations where we want to avoid one device taking all or + most of the write-back cache. For example in case of an NFS + mount that is prone to get stuck, or a FUSE mount which cannot + be trusted to play fair. diff --git a/Documentation/DocBook/Makefile b/Documentation/DocBook/Makefile index 83966e94cc3..0eb0d027eb3 100644 --- a/Documentation/DocBook/Makefile +++ b/Documentation/DocBook/Makefile @@ -12,7 +12,7 @@ DOCBOOKS := wanbook.xml z8530book.xml mcabook.xml videobook.xml \ kernel-api.xml filesystems.xml lsm.xml usb.xml kgdb.xml \ gadget.xml libata.xml mtdnand.xml librs.xml rapidio.xml \ genericirq.xml s390-drivers.xml uio-howto.xml scsi.xml \ - mac80211.xml + mac80211.xml debugobjects.xml ### # The build process is as follows (targets): diff --git a/Documentation/DocBook/debugobjects.tmpl b/Documentation/DocBook/debugobjects.tmpl new file mode 100644 index 00000000000..7f5f218015f --- /dev/null +++ b/Documentation/DocBook/debugobjects.tmpl @@ -0,0 +1,391 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN" + "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" []> + +<book id="debug-objects-guide"> + <bookinfo> + <title>Debug objects life time</title> + + <authorgroup> + <author> + <firstname>Thomas</firstname> + <surname>Gleixner</surname> + <affiliation> + <address> + <email>tglx@linutronix.de</email> + </address> + </affiliation> + </author> + </authorgroup> + + <copyright> + <year>2008</year> + <holder>Thomas Gleixner</holder> + </copyright> + + <legalnotice> + <para> + This documentation is free software; you can redistribute + it and/or modify it under the terms of the GNU General Public + License version 2 as published by the Free Software Foundation. + </para> + + <para> + This program is distributed in the hope that it will be + useful, but WITHOUT ANY WARRANTY; without even the implied + warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. + See the GNU General Public License for more details. + </para> + + <para> + You should have received a copy of the GNU General Public + License along with this program; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, + MA 02111-1307 USA + </para> + + <para> + For more details see the file COPYING in the source + distribution of Linux. + </para> + </legalnotice> + </bookinfo> + +<toc></toc> + + <chapter id="intro"> + <title>Introduction</title> + <para> + debugobjects is a generic infrastructure to track the life time + of kernel objects and validate the operations on those. + </para> + <para> + debugobjects is useful to check for the following error patterns: + <itemizedlist> + <listitem><para>Activation of uninitialized objects</para></listitem> + <listitem><para>Initialization of active objects</para></listitem> + <listitem><para>Usage of freed/destroyed objects</para></listitem> + </itemizedlist> + </para> + <para> + debugobjects is not changing the data structure of the real + object so it can be compiled in with a minimal runtime impact + and enabled on demand with a kernel command line option. + </para> + </chapter> + + <chapter id="howto"> + <title>Howto use debugobjects</title> + <para> + A kernel subsystem needs to provide a data structure which + describes the object type and add calls into the debug code at + appropriate places. The data structure to describe the object + type needs at minimum the name of the object type. Optional + functions can and should be provided to fixup detected problems + so the kernel can continue to work and the debug information can + be retrieved from a live system instead of hard core debugging + with serial consoles and stack trace transcripts from the + monitor. + </para> + <para> + The debug calls provided by debugobjects are: + <itemizedlist> + <listitem><para>debug_object_init</para></listitem> + <listitem><para>debug_object_init_on_stack</para></listitem> + <listitem><para>debug_object_activate</para></listitem> + <listitem><para>debug_object_deactivate</para></listitem> + <listitem><para>debug_object_destroy</para></listitem> + <listitem><para>debug_object_free</para></listitem> + </itemizedlist> + Each of these functions takes the address of the real object and + a pointer to the object type specific debug description + structure. + </para> + <para> + Each detected error is reported in the statistics and a limited + number of errors are printk'ed including a full stack trace. + </para> + <para> + The statistics are available via debugfs/debug_objects/stats. + They provide information about the number of warnings and the + number of successful fixups along with information about the + usage of the internal tracking objects and the state of the + internal tracking objects pool. + </para> + </chapter> + <chapter id="debugfunctions"> + <title>Debug functions</title> + <sect1 id="prototypes"> + <title>Debug object function reference</title> +!Elib/debugobjects.c + </sect1> + <sect1 id="debug_object_init"> + <title>debug_object_init</title> + <para> + This function is called whenever the initialization function + of a real object is called. + </para> + <para> + When the real object is already tracked by debugobjects it is + checked, whether the object can be initialized. Initializing + is not allowed for active and destroyed objects. When + debugobjects detects an error, then it calls the fixup_init + function of the object type description structure if provided + by the caller. The fixup function can correct the problem + before the real initialization of the object happens. E.g. it + can deactivate an active object in order to prevent damage to + the subsystem. + </para> + <para> + When the real object is not yet tracked by debugobjects, + debugobjects allocates a tracker object for the real object + and sets the tracker object state to ODEBUG_STATE_INIT. It + verifies that the object is not on the callers stack. If it is + on the callers stack then a limited number of warnings + including a full stack trace is printk'ed. The calling code + must use debug_object_init_on_stack() and remove the object + before leaving the function which allocated it. See next + section. + </para> + </sect1> + + <sect1 id="debug_object_init_on_stack"> + <title>debug_object_init_on_stack</title> + <para> + This function is called whenever the initialization function + of a real object which resides on the stack is called. + </para> + <para> + When the real object is already tracked by debugobjects it is + checked, whether the object can be initialized. Initializing + is not allowed for active and destroyed objects. When + debugobjects detects an error, then it calls the fixup_init + function of the object type description structure if provided + by the caller. The fixup function can correct the problem + before the real initialization of the object happens. E.g. it + can deactivate an active object in order to prevent damage to + the subsystem. + </para> + <para> + When the real object is not yet tracked by debugobjects + debugobjects allocates a tracker object for the real object + and sets the tracker object state to ODEBUG_STATE_INIT. It + verifies that the object is on the callers stack. + </para> + <para> + An object which is on the stack must be removed from the + tracker by calling debug_object_free() before the function + which allocates the object returns. Otherwise we keep track of + stale objects. + </para> + </sect1> + + <sect1 id="debug_object_activate"> + <title>debug_object_activate</title> + <para> + This function is called whenever the activation function of a + real object is called. + </para> + <para> + When the real object is already tracked by debugobjects it is + checked, whether the object can be activated. Activating is + not allowed for active and destroyed objects. When + debugobjects detects an error, then it calls the + fixup_activate function of the object type description + structure if provided by the caller. The fixup function can + correct the problem before the real activation of the object + happens. E.g. it can deactivate an active object in order to + prevent damage to the subsystem. + </para> + <para> + When the real object is not yet tracked by debugobjects then + the fixup_activate function is called if available. This is + necessary to allow the legitimate activation of statically + allocated and initialized objects. The fixup function checks + whether the object is valid and calls the debug_objects_init() + function to initialize the tracking of this object. + </para> + <para> + When the activation is legitimate, then the state of the + associated tracker object is set to ODEBUG_STATE_ACTIVE. + </para> + </sect1> + + <sect1 id="debug_object_deactivate"> + <title>debug_object_deactivate</title> + <para> + This function is called whenever the deactivation function of + a real object is called. + </para> + <para> + When the real object is tracked by debugobjects it is checked, + whether the object can be deactivated. Deactivating is not + allowed for untracked or destroyed objects. + </para> + <para> + When the deactivation is legitimate, then the state of the + associated tracker object is set to ODEBUG_STATE_INACTIVE. + </para> + </sect1> + + <sect1 id="debug_object_destroy"> + <title>debug_object_destroy</title> + <para> + This function is called to mark an object destroyed. This is + useful to prevent the usage of invalid objects, which are + still available in memory: either statically allocated objects + or objects which are freed later. + </para> + <para> + When the real object is tracked by debugobjects it is checked, + whether the object can be destroyed. Destruction is not + allowed for active and destroyed objects. When debugobjects + detects an error, then it calls the fixup_destroy function of + the object type description structure if provided by the + caller. The fixup function can correct the problem before the + real destruction of the object happens. E.g. it can deactivate + an active object in order to prevent damage to the subsystem. + </para> + <para> + When the destruction is legitimate, then the state of the + associated tracker object is set to ODEBUG_STATE_DESTROYED. + </para> + </sect1> + + <sect1 id="debug_object_free"> + <title>debug_object_free</title> + <para> + This function is called before an object is freed. + </para> + <para> + When the real object is tracked by debugobjects it is checked, + whether the object can be freed. Free is not allowed for + active objects. When debugobjects detects an error, then it + calls the fixup_free function of the object type description + structure if provided by the caller. The fixup function can + correct the problem before the real free of the object + happens. E.g. it can deactivate an active object in order to + prevent damage to the subsystem. + </para> + <para> + Note that debug_object_free removes the object from the + tracker. Later usage of the object is detected by the other + debug checks. + </para> + </sect1> + </chapter> + <chapter id="fixupfunctions"> + <title>Fixup functions</title> + <sect1 id="debug_obj_descr"> + <title>Debug object type description structure</title> +!Iinclude/linux/debugobjects.h + </sect1> + <sect1 id="fixup_init"> + <title>fixup_init</title> + <para> + This function is called from the debug code whenever a problem + in debug_object_init is detected. The function takes the + address of the object and the state which is currently + recorded in the tracker. + </para> + <para> + Called from debug_object_init when the object state is: + <itemizedlist> + <listitem><para>ODEBUG_STATE_ACTIVE</para></listitem> + </itemizedlist> + </para> + <para> + The function returns 1 when the fixup was successful, + otherwise 0. The return value is used to update the + statistics. + </para> + <para> + Note, that the function needs to call the debug_object_init() + function again, after the damage has been repaired in order to + keep the state consistent. + </para> + </sect1> + + <sect1 id="fixup_activate"> + <title>fixup_activate</title> + <para> + This function is called from the debug code whenever a problem + in debug_object_activate is detected. + </para> + <para> + Called from debug_object_activate when the object state is: + <itemizedlist> + <listitem><para>ODEBUG_STATE_NOTAVAILABLE</para></listitem> + <listitem><para>ODEBUG_STATE_ACTIVE</para></listitem> + </itemizedlist> + </para> + <para> + The function returns 1 when the fixup was successful, + otherwise 0. The return value is used to update the + statistics. + </para> + <para> + Note that the function needs to call the debug_object_activate() + function again after the damage has been repaired in order to + keep the state consistent. + </para> + <para> + The activation of statically initialized objects is a special + case. When debug_object_activate() has no tracked object for + this object address then fixup_activate() is called with + object state ODEBUG_STATE_NOTAVAILABLE. The fixup function + needs to check whether this is a legitimate case of a + statically initialized object or not. In case it is it calls + debug_object_init() and debug_object_activate() to make the + object known to the tracker and marked active. In this case + the function should return 0 because this is not a real fixup. + </para> + </sect1> + + <sect1 id="fixup_destroy"> + <title>fixup_destroy</title> + <para> + This function is called from the debug code whenever a problem + in debug_object_destroy is detected. + </para> + <para> + Called from debug_object_destroy when the object state is: + <itemizedlist> + <listitem><para>ODEBUG_STATE_ACTIVE</para></listitem> + </itemizedlist> + </para> + <para> + The function returns 1 when the fixup was successful, + otherwise 0. The return value is used to update the + statistics. + </para> + </sect1> + <sect1 id="fixup_free"> + <title>fixup_free</title> + <para> + This function is called from the debug code whenever a problem + in debug_object_free is detected. Further it can be called + from the debug checks in kfree/vfree, when an active object is + detected from the debug_check_no_obj_freed() sanity checks. + </para> + <para> + Called from debug_object_free() or debug_check_no_obj_freed() + when the object state is: + <itemizedlist> + <listitem><para>ODEBUG_STATE_ACTIVE</para></listitem> + </itemizedlist> + </para> + <para> + The function returns 1 when the fixup was successful, + otherwise 0. The return value is used to update the + statistics. + </para> + </sect1> + </chapter> + <chapter id="bugs"> + <title>Known Bugs And Assumptions</title> + <para> + None (knock on wood). + </para> + </chapter> +</book> diff --git a/Documentation/DocBook/rapidio.tmpl b/Documentation/DocBook/rapidio.tmpl index b9e143e28c6..54eb26b5737 100644 --- a/Documentation/DocBook/rapidio.tmpl +++ b/Documentation/DocBook/rapidio.tmpl @@ -133,7 +133,6 @@ !Idrivers/rapidio/rio-sysfs.c </sect1> <sect1 id="PPC32_support"><title>PPC32 support</title> -!Iarch/powerpc/kernel/rio.c !Earch/powerpc/sysdev/fsl_rio.c !Iarch/powerpc/sysdev/fsl_rio.c </sect1> diff --git a/Documentation/braille-console.txt b/Documentation/braille-console.txt new file mode 100644 index 00000000000..000b0fbdc10 --- /dev/null +++ b/Documentation/braille-console.txt @@ -0,0 +1,34 @@ + Linux Braille Console + +To get early boot messages on a braille device (before userspace screen +readers can start), you first need to compile the support for the usual serial +console (see serial-console.txt), and for braille device (in Device Drivers - +Accessibility). + +Then you need to specify a console=brl, option on the kernel command line, the +format is: + + console=brl,serial_options... + +where serial_options... are the same as described in serial-console.txt + +So for instance you can use console=brl,ttyS0 if the braille device is connected +to the first serial port, and console=brl,ttyS0,115200 to override the baud rate +to 115200, etc. + +By default, the braille device will just show the last kernel message (console +mode). To review previous messages, press the Insert key to switch to the VT +review mode. In review mode, the arrow keys permit to browse in the VT content, +page up/down keys go at the top/bottom of the screen, and the home key goes back +to the cursor, hence providing very basic screen reviewing facility. + +Sound feedback can be obtained by adding the braille_console.sound=1 kernel +parameter. + +For simplicity, only one braille console can be enabled, other uses of +console=brl,... will be discarded. Also note that it does not interfere with +the console selection mecanism described in serial-console.txt + +For now, only the VisioBraille device is supported. + +Samuel Thibault <samuel.thibault@ens-lyon.org> diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 599fe55bf29..3c35d452b1a 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -138,6 +138,24 @@ Who: Kay Sievers <kay.sievers@suse.de> --------------------------- +What: find_task_by_pid +When: 2.6.26 +Why: With pid namespaces, calling this funciton will return the + wrong task when called from inside a namespace. + + The best way to save a task pid and find a task by this + pid later, is to find this task's struct pid pointer (or get + it directly from the task) and call pid_task() later. + + If someone really needs to get a task by its pid_t, then + he most likely needs the find_task_by_vpid() to get the + task from the same namespace as the current task is in, but + this may be not so in general. + +Who: Pavel Emelyanov <xemul@openvz.org> + +--------------------------- + What: ACPI procfs interface When: July 2008 Why: ACPI sysfs conversion should be finished by January 2008. diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index 2a99116edc4..dbc3c6a3650 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -463,11 +463,17 @@ SwapTotal: 0 kB SwapFree: 0 kB Dirty: 968 kB Writeback: 0 kB +AnonPages: 861800 kB Mapped: 280372 kB -Slab: 684068 kB +Slab: 284364 kB +SReclaimable: 159856 kB +SUnreclaim: 124508 kB +PageTables: 24448 kB +NFS_Unstable: 0 kB +Bounce: 0 kB +WritebackTmp: 0 kB CommitLimit: 7669796 kB Committed_AS: 100056 kB -PageTables: 24448 kB VmallocTotal: 112216 kB VmallocUsed: 428 kB VmallocChunk: 111088 kB @@ -503,8 +509,17 @@ VmallocChunk: 111088 kB on the disk Dirty: Memory which is waiting to get written back to the disk Writeback: Memory which is actively being written back to the disk + AnonPages: Non-file backed pages mapped into userspace page tables Mapped: files which have been mmaped, such as libraries Slab: in-kernel data structures cache +SReclaimable: Part of Slab, that might be reclaimed, such as caches + SUnreclaim: Part of Slab, that cannot be reclaimed on memory pressure + PageTables: amount of memory dedicated to the lowest level of page + tables. +NFS_Unstable: NFS pages sent to the server, but not yet committed to stable + storage + Bounce: Memory used for block device "bounce buffers" +WritebackTmp: Memory used by FUSE for temporary writeback buffers CommitLimit: Based on the overcommit ratio ('vm.overcommit_ratio'), this is the total amount of memory currently available to be allocated on the system. This limit is only adhered to @@ -531,8 +546,6 @@ Committed_AS: The amount of memory presently allocated on the system. above) will not be permitted. This is useful if one needs to guarantee that processes will not fail due to lack of memory once that memory has been successfully allocated. - PageTables: amount of memory dedicated to the lowest level of page - tables. VmallocTotal: total size of vmalloc memory area VmallocUsed: amount of vmalloc area which is used VmallocChunk: largest contigious block of vmalloc area which is free diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 3ce193f8656..a3c35446e75 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -496,6 +496,11 @@ and is between 256 and 4096 characters. It is defined in the file switching to the matching ttyS device later. The options are the same as for ttyS, above. + If the device connected to the port is not a TTY but a braille + device, prepend "brl," before the device type, for instance + console=brl,ttyS0 + For now, only VisioBraille is supported. + earlycon= [KNL] Output early console device and options. uart[8250],io,<addr>[,options] uart[8250],mmio,<addr>[,options] @@ -556,6 +561,8 @@ and is between 256 and 4096 characters. It is defined in the file 1 will print _a lot_ more information - normally only useful to kernel developers. + debug_objects [KNL] Enable object debugging + decnet.addr= [HW,NET] Format: <area>[,<node>] See also Documentation/networking/decnet.txt. diff --git a/Documentation/powerpc/mpc52xx-device-tree-bindings.txt b/Documentation/powerpc/mpc52xx-device-tree-bindings.txt index 5e03610e186..cda7a7dffa6 100644 --- a/Documentation/powerpc/mpc52xx-device-tree-bindings.txt +++ b/Documentation/powerpc/mpc52xx-device-tree-bindings.txt @@ -186,6 +186,12 @@ Recommended soc5200 child nodes; populate as needed for your board name device_type compatible Description ---- ----------- ---------- ----------- gpt@<addr> gpt fsl,mpc5200-gpt General purpose timers +gpt@<addr> gpt fsl,mpc5200-gpt-gpio General purpose + timers in GPIO mode +gpio@<addr> fsl,mpc5200-gpio MPC5200 simple gpio + controller +gpio@<addr> fsl,mpc5200-gpio-wkup MPC5200 wakeup gpio + controller rtc@<addr> rtc mpc5200-rtc Real time clock mscan@<addr> mscan mpc5200-mscan CAN bus controller pci@<addr> pci mpc5200-pci PCI bridge @@ -225,6 +231,12 @@ PSC in i2s mode: The mpc5200 and mpc5200b PSCs are not compatible when in i2s mode. An 'mpc5200b-psc-i2s' node cannot include 'mpc5200-psc-i2s' in the compatible field. +7) GPIO controller nodes +Each GPIO controller node should have the empty property gpio-controller and +#gpio-cells set to 2. First cell is the GPIO number which is interpreted +according to the bit numbers in the GPIO control registers. The second cell +is for flags which is currently unsused. + IV - Extra Notes ================ |