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-rw-r--r--Documentation/ABI/testing/debugfs-kmemtrace71
-rw-r--r--Documentation/ABI/testing/sysfs-bus-pci27
-rw-r--r--Documentation/DocBook/device-drivers.tmpl1
-rw-r--r--Documentation/DocBook/kgdb.tmpl108
-rw-r--r--Documentation/DocBook/stylesheet.xsl1
-rw-r--r--Documentation/coccinelle.txt258
-rw-r--r--Documentation/feature-removal-schedule.txt33
-rw-r--r--Documentation/filesystems/caching/fscache.txt10
-rw-r--r--Documentation/filesystems/sysfs-pci.txt7
-rw-r--r--Documentation/filesystems/sysfs.txt46
-rw-r--r--Documentation/firmware_class/hotplug-script17
-rw-r--r--Documentation/hwmon/pkgtemp36
-rw-r--r--Documentation/kbuild/kbuild.txt34
-rw-r--r--Documentation/kbuild/kconfig.txt2
-rw-r--r--Documentation/kbuild/makefiles.txt127
-rw-r--r--Documentation/kernel-parameters.txt27
-rw-r--r--Documentation/pcmcia/driver-changes.txt12
-rw-r--r--Documentation/slow-work.txt322
-rw-r--r--Documentation/timers/timers-howto.txt105
-rw-r--r--Documentation/trace/ftrace-design.txt153
-rw-r--r--Documentation/trace/kmemtrace.txt126
-rw-r--r--Documentation/trace/kprobetrace.txt2
-rw-r--r--Documentation/vm/page-types.c2
-rw-r--r--Documentation/x86/zero-page.txt1
24 files changed, 858 insertions, 670 deletions
diff --git a/Documentation/ABI/testing/debugfs-kmemtrace b/Documentation/ABI/testing/debugfs-kmemtrace
deleted file mode 100644
index 5e6a92a..0000000
--- a/Documentation/ABI/testing/debugfs-kmemtrace
+++ /dev/null
@@ -1,71 +0,0 @@
-What: /sys/kernel/debug/kmemtrace/
-Date: July 2008
-Contact: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
-Description:
-
-In kmemtrace-enabled kernels, the following files are created:
-
-/sys/kernel/debug/kmemtrace/
- cpu<n> (0400) Per-CPU tracing data, see below. (binary)
- total_overruns (0400) Total number of bytes which were dropped from
- cpu<n> files because of full buffer condition,
- non-binary. (text)
- abi_version (0400) Kernel's kmemtrace ABI version. (text)
-
-Each per-CPU file should be read according to the relay interface. That is,
-the reader should set affinity to that specific CPU and, as currently done by
-the userspace application (though there are other methods), use poll() with
-an infinite timeout before every read(). Otherwise, erroneous data may be
-read. The binary data has the following _core_ format:
-
- Event ID (1 byte) Unsigned integer, one of:
- 0 - represents an allocation (KMEMTRACE_EVENT_ALLOC)
- 1 - represents a freeing of previously allocated memory
- (KMEMTRACE_EVENT_FREE)
- Type ID (1 byte) Unsigned integer, one of:
- 0 - this is a kmalloc() / kfree()
- 1 - this is a kmem_cache_alloc() / kmem_cache_free()
- 2 - this is a __get_free_pages() et al.
- Event size (2 bytes) Unsigned integer representing the
- size of this event. Used to extend
- kmemtrace. Discard the bytes you
- don't know about.
- Sequence number (4 bytes) Signed integer used to reorder data
- logged on SMP machines. Wraparound
- must be taken into account, although
- it is unlikely.
- Caller address (8 bytes) Return address to the caller.
- Pointer to mem (8 bytes) Pointer to target memory area. Can be
- NULL, but not all such calls might be
- recorded.
-
-In case of KMEMTRACE_EVENT_ALLOC events, the next fields follow:
-
- Requested bytes (8 bytes) Total number of requested bytes,
- unsigned, must not be zero.
- Allocated bytes (8 bytes) Total number of actually allocated
- bytes, unsigned, must not be lower
- than requested bytes.
- Requested flags (4 bytes) GFP flags supplied by the caller.
- Target CPU (4 bytes) Signed integer, valid for event id 1.
- If equal to -1, target CPU is the same
- as origin CPU, but the reverse might
- not be true.
-
-The data is made available in the same endianness the machine has.
-
-Other event ids and type ids may be defined and added. Other fields may be
-added by increasing event size, but see below for details.
-Every modification to the ABI, including new id definitions, are followed
-by bumping the ABI version by one.
-
-Adding new data to the packet (features) is done at the end of the mandatory
-data:
- Feature size (2 byte)
- Feature ID (1 byte)
- Feature data (Feature size - 3 bytes)
-
-
-Users:
- kmemtrace-user - git://repo.or.cz/kmemtrace-user.git
-
diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci
index 25be325..f979d82 100644
--- a/Documentation/ABI/testing/sysfs-bus-pci
+++ b/Documentation/ABI/testing/sysfs-bus-pci
@@ -139,3 +139,30 @@ Contact: linux-pci@vger.kernel.org
Description:
This symbolic link points to the PCI hotplug controller driver
module that manages the hotplug slot.
+
+What: /sys/bus/pci/devices/.../label
+Date: July 2010
+Contact: Narendra K <narendra_k@dell.com>, linux-bugs@dell.com
+Description:
+ Reading this attribute will provide the firmware
+ given name(SMBIOS type 41 string) of the PCI device.
+ The attribute will be created only if the firmware
+ has given a name to the PCI device.
+Users:
+ Userspace applications interested in knowing the
+ firmware assigned name of the PCI device.
+
+What: /sys/bus/pci/devices/.../index
+Date: July 2010
+Contact: Narendra K <narendra_k@dell.com>, linux-bugs@dell.com
+Description:
+ Reading this attribute will provide the firmware
+ given instance(SMBIOS type 41 device type instance)
+ of the PCI device. The attribute will be created
+ only if the firmware has given a device type instance
+ to the PCI device.
+Users:
+ Userspace applications interested in knowing the
+ firmware assigned device type instance of the PCI
+ device that can help in understanding the firmware
+ intended order of the PCI device.
diff --git a/Documentation/DocBook/device-drivers.tmpl b/Documentation/DocBook/device-drivers.tmpl
index 1b2dd4f..ecd35e9 100644
--- a/Documentation/DocBook/device-drivers.tmpl
+++ b/Documentation/DocBook/device-drivers.tmpl
@@ -111,6 +111,7 @@ X!Edrivers/base/attribute_container.c
<!--
X!Edrivers/base/interface.c
-->
+!Iinclude/linux/platform_device.h
!Edrivers/base/platform.c
!Edrivers/base/bus.c
</sect1>
diff --git a/Documentation/DocBook/kgdb.tmpl b/Documentation/DocBook/kgdb.tmpl
index 55f12ac..490d862 100644
--- a/Documentation/DocBook/kgdb.tmpl
+++ b/Documentation/DocBook/kgdb.tmpl
@@ -199,10 +199,33 @@
may be configured as a kernel built-in or a kernel loadable module.
You can only make use of <constant>kgdbwait</constant> and early
debugging if you build kgdboc into the kernel as a built-in.
+ <para>Optionally you can elect to activate kms (Kernel Mode
+ Setting) integration. When you use kms with kgdboc and you have a
+ video driver that has atomic mode setting hooks, it is possible to
+ enter the debugger on the graphics console. When the kernel
+ execution is resumed, the previous graphics mode will be restored.
+ This integration can serve as a useful tool to aid in diagnosing
+ crashes or doing analysis of memory with kdb while allowing the
+ full graphics console applications to run.
+ </para>
</para>
<sect2 id="kgdbocArgs">
<title>kgdboc arguments</title>
- <para>Usage: <constant>kgdboc=[kbd][[,]serial_device][,baud]</constant></para>
+ <para>Usage: <constant>kgdboc=[kms][[,]kbd][[,]serial_device][,baud]</constant></para>
+ <para>The order listed above must be observed if you use any of the
+ optional configurations together.
+ </para>
+ <para>Abbreviations:
+ <itemizedlist>
+ <listitem><para>kms = Kernel Mode Setting</para></listitem>
+ <listitem><para>kbd = Keyboard</para></listitem>
+ </itemizedlist>
+ </para>
+ <para>You can configure kgdboc to use the keyboard, and or a serial
+ device depending on if you are using kdb and or kgdb, in one of the
+ following scenarios. The order listed above must be observed if
+ you use any of the optional configurations together. Using kms +
+ only gdb is generally not a useful combination.</para>
<sect3 id="kgdbocArgs1">
<title>Using loadable module or built-in</title>
<para>
@@ -212,7 +235,7 @@
<listitem>
<para>As a kernel loadable module:</para>
<para>Use the command: <constant>modprobe kgdboc kgdboc=&lt;tty-device&gt;,[baud]</constant></para>
- <para>Here are two examples of how you might formate the kgdboc
+ <para>Here are two examples of how you might format the kgdboc
string. The first is for an x86 target using the first serial port.
The second example is for the ARM Versatile AB using the second
serial port.
@@ -240,6 +263,9 @@
</sect3>
<sect3 id="kgdbocArgs3">
<title>More examples</title>
+ <para>You can configure kgdboc to use the keyboard, and or a serial
+ device depending on if you are using kdb and or kgdb, in one of the
+ following scenarios.</para>
<para>You can configure kgdboc to use the keyboard, and or a serial device
depending on if you are using kdb and or kgdb, in one of the
following scenarios.
@@ -255,6 +281,12 @@
<listitem><para>kdb with a keyboard</para>
<para><constant>kgdboc=kbd</constant></para>
</listitem>
+ <listitem><para>kdb with kernel mode setting</para>
+ <para><constant>kgdboc=kms,kbd</constant></para>
+ </listitem>
+ <listitem><para>kdb with kernel mode setting and kgdb over a serial port</para>
+ <para><constant>kgdboc=kms,kbd,ttyS0,115200</constant></para>
+ </listitem>
</orderedlist>
</para>
</sect3>
@@ -637,6 +669,8 @@ Task Addr Pid Parent [*] cpu State Thread Command
<listitem><para>The logic to perform safe memory reads and writes to memory while using the debugger</para></listitem>
<listitem><para>A full implementation for software breakpoints unless overridden by the arch</para></listitem>
<listitem><para>The API to invoke either the kdb or kgdb frontend to the debug core.</para></listitem>
+ <listitem><para>The structures and callback API for atomic kernel mode setting.</para>
+ <para>NOTE: kgdboc is where the kms callbacks are invoked.</para></listitem>
</itemizedlist>
</para>
</listitem>
@@ -747,6 +781,8 @@ Task Addr Pid Parent [*] cpu State Thread Command
</sect1>
<sect1 id="kgdbocDesign">
<title>kgdboc internals</title>
+ <sect2>
+ <title>kgdboc and uarts</title>
<para>
The kgdboc driver is actually a very thin driver that relies on the
underlying low level to the hardware driver having "polling hooks"
@@ -754,11 +790,8 @@ Task Addr Pid Parent [*] cpu State Thread Command
implementation of kgdboc it the serial_core was changed to expose a
low level UART hook for doing polled mode reading and writing of a
single character while in an atomic context. When kgdb makes an I/O
- request to the debugger, kgdboc invokes a call back in the serial
- core which in turn uses the call back in the UART driver. It is
- certainly possible to extend kgdboc to work with non-UART based
- consoles in the future.
- </para>
+ request to the debugger, kgdboc invokes a callback in the serial
+ core which in turn uses the callback in the UART driver.</para>
<para>
When using kgdboc with a UART, the UART driver must implement two callbacks in the <constant>struct uart_ops</constant>. Example from drivers/8250.c:<programlisting>
#ifdef CONFIG_CONSOLE_POLL
@@ -772,9 +805,68 @@ Task Addr Pid Parent [*] cpu State Thread Command
that they can be called from an atomic context and have to restore
the state of the UART chip on return such that the system can return
to normal when the debugger detaches. You need to be very careful
- with any kind of lock you consider, because failing here is most
+ with any kind of lock you consider, because failing here is most likely
going to mean pressing the reset button.
</para>
+ </sect2>
+ <sect2 id="kgdbocKbd">
+ <title>kgdboc and keyboards</title>
+ <para>The kgdboc driver contains logic to configure communications
+ with an attached keyboard. The keyboard infrastructure is only
+ compiled into the kernel when CONFIG_KDB_KEYBOARD=y is set in the
+ kernel configuration.</para>
+ <para>The core polled keyboard driver driver for PS/2 type keyboards
+ is in drivers/char/kdb_keyboard.c. This driver is hooked into the
+ debug core when kgdboc populates the callback in the array
+ called <constant>kdb_poll_funcs[]</constant>. The
+ kdb_get_kbd_char() is the top-level function which polls hardware
+ for single character input.
+ </para>
+ </sect2>
+ <sect2 id="kgdbocKms">
+ <title>kgdboc and kms</title>
+ <para>The kgdboc driver contains logic to request the graphics
+ display to switch to a text context when you are using
+ "kgdboc=kms,kbd", provided that you have a video driver which has a
+ frame buffer console and atomic kernel mode setting support.</para>
+ <para>
+ Every time the kernel
+ debugger is entered it calls kgdboc_pre_exp_handler() which in turn
+ calls con_debug_enter() in the virtual console layer. On resuming kernel
+ execution, the kernel debugger calls kgdboc_post_exp_handler() which
+ in turn calls con_debug_leave().</para>
+ <para>Any video driver that wants to be compatible with the kernel
+ debugger and the atomic kms callbacks must implement the
+ mode_set_base_atomic, fb_debug_enter and fb_debug_leave operations.
+ For the fb_debug_enter and fb_debug_leave the option exists to use
+ the generic drm fb helper functions or implement something custom for
+ the hardware. The following example shows the initialization of the
+ .mode_set_base_atomic operation in
+ drivers/gpu/drm/i915/intel_display.c:
+ <informalexample>
+ <programlisting>
+static const struct drm_crtc_helper_funcs intel_helper_funcs = {
+[...]
+ .mode_set_base_atomic = intel_pipe_set_base_atomic,
+[...]
+};
+ </programlisting>
+ </informalexample>
+ </para>
+ <para>Here is an example of how the i915 driver initializes the fb_debug_enter and fb_debug_leave functions to use the generic drm helpers in
+ drivers/gpu/drm/i915/intel_fb.c:
+ <informalexample>
+ <programlisting>
+static struct fb_ops intelfb_ops = {
+[...]
+ .fb_debug_enter = drm_fb_helper_debug_enter,
+ .fb_debug_leave = drm_fb_helper_debug_leave,
+[...]
+};
+ </programlisting>
+ </informalexample>
+ </para>
+ </sect2>
</sect1>
</chapter>
<chapter id="credits">
diff --git a/Documentation/DocBook/stylesheet.xsl b/Documentation/DocBook/stylesheet.xsl
index 254c1d5..85b2527 100644
--- a/Documentation/DocBook/stylesheet.xsl
+++ b/Documentation/DocBook/stylesheet.xsl
@@ -6,4 +6,5 @@
<param name="callout.graphics">0</param>
<!-- <param name="paper.type">A4</param> -->
<param name="generate.section.toc.level">2</param>
+<param name="use.id.as.filename">1</param>
</stylesheet>
diff --git a/Documentation/coccinelle.txt b/Documentation/coccinelle.txt
new file mode 100644
index 0000000..cd2b028
--- /dev/null
+++ b/Documentation/coccinelle.txt
@@ -0,0 +1,258 @@
+Copyright 2010 Nicolas Palix <npalix@diku.dk>
+Copyright 2010 Julia Lawall <julia@diku.dk>
+Copyright 2010 Gilles Muller <Gilles.Muller@lip6.fr>
+
+
+ Getting Coccinelle
+~~~~~~~~~~~~~~~~~~~~
+
+The semantic patches included in the kernel use the 'virtual rule'
+feature which was introduced in Coccinelle version 0.1.11.
+
+Coccinelle (>=0.2.0) is available through the package manager
+of many distributions, e.g. :
+
+ - Debian (>=squeeze)
+ - Fedora (>=13)
+ - Ubuntu (>=10.04 Lucid Lynx)
+ - OpenSUSE
+ - Arch Linux
+ - NetBSD
+ - FreeBSD
+
+
+You can get the latest version released from the Coccinelle homepage at
+http://coccinelle.lip6.fr/
+
+Once you have it, run the following command:
+
+ ./configure
+ make
+
+as a regular user, and install it with
+
+ sudo make install
+
+
+ Using Coccinelle on the Linux kernel
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+A Coccinelle-specific target is defined in the top level
+Makefile. This target is named 'coccicheck' and calls the 'coccicheck'
+front-end in the 'scripts' directory.
+
+Four modes are defined: report, patch, context, and org. The mode to
+use is specified by setting the MODE variable with 'MODE=<mode>'.
+
+'report' generates a list in the following format:
+ file:line:column-column: message
+
+'patch' proposes a fix, when possible.
+
+'context' highlights lines of interest and their context in a
+diff-like style.Lines of interest are indicated with '-'.
+
+'org' generates a report in the Org mode format of Emacs.
+
+Note that not all semantic patches implement all modes.
+
+To make a report for every semantic patch, run the following command:
+
+ make coccicheck MODE=report
+
+NB: The 'report' mode is the default one.
+
+To produce patches, run:
+
+ make coccicheck MODE=patch
+
+
+The coccicheck target applies every semantic patch available in the
+subdirectories of 'scripts/coccinelle' to the entire Linux kernel.
+
+For each semantic patch, a changelog message is proposed. It gives a
+description of the problem being checked by the semantic patch, and
+includes a reference to Coccinelle.
+
+As any static code analyzer, Coccinelle produces false
+positives. Thus, reports must be carefully checked, and patches
+reviewed.
+
+
+ Using Coccinelle with a single semantic patch
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The optional make variable COCCI can be used to check a single
+semantic patch. In that case, the variable must be initialized with
+the name of the semantic patch to apply.
+
+For instance:
+
+ make coccicheck COCCI=<my_SP.cocci> MODE=patch
+or
+ make coccicheck COCCI=<my_SP.cocci> MODE=report
+
+
+ Proposing new semantic patches
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+New semantic patches can be proposed and submitted by kernel
+developers. For sake of clarity, they should be organized in the
+subdirectories of 'scripts/coccinelle/'.
+
+
+ Detailed description of the 'report' mode
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+'report' generates a list in the following format:
+ file:line:column-column: message
+
+Example:
+
+Running
+
+ make coccicheck MODE=report COCCI=scripts/coccinelle/err_cast.cocci
+
+will execute the following part of the SmPL script.
+
+<smpl>
+@r depends on !context && !patch && (org || report)@
+expression x;
+position p;
+@@
+
+ ERR_PTR@p(PTR_ERR(x))
+
+@script:python depends on report@
+p << r.p;
+x << r.x;
+@@
+
+msg="ERR_CAST can be used with %s" % (x)
+coccilib.report.print_report(p[0], msg)
+</smpl>
+
+This SmPL excerpt generates entries on the standard output, as
+illustrated below:
+
+/home/user/linux/crypto/ctr.c:188:9-16: ERR_CAST can be used with alg
+/home/user/linux/crypto/authenc.c:619:9-16: ERR_CAST can be used with auth
+/home/user/linux/crypto/xts.c:227:9-16: ERR_CAST can be used with alg
+
+
+ Detailed description of the 'patch' mode
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+When the 'patch' mode is available, it proposes a fix for each problem
+identified.
+
+Example:
+
+Running
+ make coccicheck MODE=patch COCCI=scripts/coccinelle/err_cast.cocci
+
+will execute the following part of the SmPL script.
+
+<smpl>
+@ depends on !context && patch && !org && !report @
+expression x;
+@@
+
+- ERR_PTR(PTR_ERR(x))
++ ERR_CAST(x)
+</smpl>
+
+This SmPL excerpt generates patch hunks on the standard output, as
+illustrated below:
+
+diff -u -p a/crypto/ctr.c b/crypto/ctr.c
+--- a/crypto/ctr.c 2010-05-26 10:49:38.000000000 +0200
++++ b/crypto/ctr.c 2010-06-03 23:44:49.000000000 +0200
+@@ -185,7 +185,7 @@ static struct crypto_instance *crypto_ct
+ alg = crypto_attr_alg(tb[1], CRYPTO_ALG_TYPE_CIPHER,
+ CRYPTO_ALG_TYPE_MASK);
+ if (IS_ERR(alg))
+- return ERR_PTR(PTR_ERR(alg));
++ return ERR_CAST(alg);
+
+ /* Block size must be >= 4 bytes. */
+ err = -EINVAL;
+
+ Detailed description of the 'context' mode
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+'context' highlights lines of interest and their context
+in a diff-like style.
+
+NOTE: The diff-like output generated is NOT an applicable patch. The
+ intent of the 'context' mode is to highlight the important lines
+ (annotated with minus, '-') and gives some surrounding context
+ lines around. This output can be used with the diff mode of
+ Emacs to review the code.
+
+Example:
+
+Running
+ make coccicheck MODE=context COCCI=scripts/coccinelle/err_cast.cocci
+
+will execute the following part of the SmPL script.
+
+<smpl>
+@ depends on context && !patch && !org && !report@
+expression x;
+@@
+
+* ERR_PTR(PTR_ERR(x))
+</smpl>
+
+This SmPL excerpt generates diff hunks on the standard output, as
+illustrated below:
+
+diff -u -p /home/user/linux/crypto/ctr.c /tmp/nothing
+--- /home/user/linux/crypto/ctr.c 2010-05-26 10:49:38.000000000 +0200
++++ /tmp/nothing
+@@ -185,7 +185,6 @@ static struct crypto_instance *crypto_ct
+ alg = crypto_attr_alg(tb[1], CRYPTO_ALG_TYPE_CIPHER,
+ CRYPTO_ALG_TYPE_MASK);
+ if (IS_ERR(alg))
+- return ERR_PTR(PTR_ERR(alg));
+
+ /* Block size must be >= 4 bytes. */
+ err = -EINVAL;
+
+ Detailed description of the 'org' mode
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+'org' generates a report in the Org mode format of Emacs.
+
+Example:
+
+Running
+ make coccicheck MODE=org COCCI=scripts/coccinelle/err_cast.cocci
+
+will execute the following part of the SmPL script.
+
+<smpl>
+@r depends on !context && !patch && (org || report)@
+expression x;
+position p;
+@@
+
+ ERR_PTR@p(PTR_ERR(x))
+
+@script:python depends on org@
+p << r.p;
+x << r.x;
+@@
+
+msg="ERR_CAST can be used with %s" % (x)
+msg_safe=msg.replace("[","@(").replace("]",")")
+coccilib.org.print_todo(p[0], msg_safe)
+</smpl>
+
+This SmPL excerpt generates Org entries on the standard output, as
+illustrated below:
+
+* TODO [[view:/home/user/linux/crypto/ctr.c::face=ovl-face1::linb=188::colb=9::cole=16][ERR_CAST can be used with alg]]
+* TODO [[view:/home/user/linux/crypto/authenc.c::face=ovl-face1::linb=619::colb=9::cole=16][ERR_CAST can be used with auth]]
+* TODO [[view:/home/user/linux/crypto/xts.c::face=ovl-face1::linb=227::colb=9::cole=16][ERR_CAST can be used with alg]]
diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index be7030e..71f0fea 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt
@@ -116,29 +116,6 @@ Who: Mauro Carvalho Chehab <mchehab@infradead.org>
---------------------------
-What: PCMCIA control ioctl (needed for pcmcia-cs [cardmgr, cardctl])
-When: 2.6.35/2.6.36
-Files: drivers/pcmcia/: pcmcia_ioctl.c
-Why: With the 16-bit PCMCIA subsystem now behaving (almost) like a
- normal hotpluggable bus, and with it using the default kernel
- infrastructure (hotplug, driver core, sysfs) keeping the PCMCIA
- control ioctl needed by cardmgr and cardctl from pcmcia-cs is
- unnecessary and potentially harmful (it does not provide for
- proper locking), and makes further cleanups and integration of the
- PCMCIA subsystem into the Linux kernel device driver model more
- difficult. The features provided by cardmgr and cardctl are either
- handled by the kernel itself now or are available in the new
- pcmciautils package available at
- http://kernel.org/pub/linux/utils/kernel/pcmcia/
-
- For all architectures except ARM, the associated config symbol
- has been removed from kernel 2.6.34; for ARM, it will be likely
- be removed from kernel 2.6.35. The actual code will then likely
- be removed from kernel 2.6.36.
-Who: Dominik Brodowski <linux@dominikbrodowski.net>
-
----------------------------
-
What: sys_sysctl
When: September 2010
Option: CONFIG_SYSCTL_SYSCALL
@@ -468,16 +445,6 @@ Who: Jan Kiszka <jan.kiszka@web.de>
----------------------------
-What: xtime, wall_to_monotonic
-When: 2.6.36+
-Files: kernel/time/timekeeping.c include/linux/time.h
-Why: Cleaning up timekeeping internal values. Please use
- existing timekeeping accessor functions to access
- the equivalent functionality.
-Who: John Stultz <johnstul@us.ibm.com>
-
-----------------------------
-
What: KVM paravirt mmu host support
When: January 2011
Why: The paravirt mmu host support is slower than non-paravirt mmu, both
diff --git a/Documentation/filesystems/caching/fscache.txt b/Documentation/filesystems/caching/fscache.txt
index a91e2e2..770267a 100644
--- a/Documentation/filesystems/caching/fscache.txt
+++ b/Documentation/filesystems/caching/fscache.txt
@@ -343,8 +343,8 @@ This will look something like:
[root@andromeda ~]# head /proc/fs/fscache/objects
OBJECT PARENT STAT CHLDN OPS OOP IPR EX READS EM EV F S | NETFS_COOKIE_DEF TY FL NETFS_DATA OBJECT_KEY, AUX_DATA
======== ======== ==== ===== === === === == ===== == == = = | ================ == == ================ ================
- 17e4b 2 ACTV 0 0 0 0 0 0 7b 4 0 8 | NFS.fh DT 0 ffff88001dd82820 010006017edcf8bbc93b43298fdfbe71e50b57b13a172c0117f38472, e567634700000000000000000000000063f2404a000000000000000000000000c9030000000000000000000063f2404a
- 1693a 2 ACTV 0 0 0 0 0 0 7b 4 0 8 | NFS.fh DT 0 ffff88002db23380 010006017edcf8bbc93b43298fdfbe71e50b57b1e0162c01a2df0ea6, 420ebc4a000000000000000000000000420ebc4a0000000000000000000000000e1801000000000000000000420ebc4a
+ 17e4b 2 ACTV 0 0 0 0 0 0 7b 4 0 0 | NFS.fh DT 0 ffff88001dd82820 010006017edcf8bbc93b43298fdfbe71e50b57b13a172c0117f38472, e567634700000000000000000000000063f2404a000000000000000000000000c9030000000000000000000063f2404a
+ 1693a 2 ACTV 0 0 0 0 0 0 7b 4 0 0 | NFS.fh DT 0 ffff88002db23380 010006017edcf8bbc93b43298fdfbe71e50b57b1e0162c01a2df0ea6, 420ebc4a000000000000000000000000420ebc4a0000000000000000000000000e1801000000000000000000420ebc4a
where the first set of columns before the '|' describe the object:
@@ -362,7 +362,7 @@ where the first set of columns before the '|' describe the object:
EM Object's event mask
EV Events raised on this object
F Object flags
- S Object slow-work work item flags
+ S Object work item busy state mask (1:pending 2:running)
and the second set of columns describe the object's cookie, if present:
@@ -395,8 +395,8 @@ and the following paired letters:
w Show objects that don't have pending writes
R Show objects that have outstanding reads
r Show objects that don't have outstanding reads
- S Show objects that have slow work queued
- s Show objects that don't have slow work queued
+ S Show objects that have work queued
+ s Show objects that don't have work queued
If neither side of a letter pair is given, then both are implied. For example:
diff --git a/Documentation/filesystems/sysfs-pci.txt b/Documentation/filesystems/sysfs-pci.txt
index 85354b3..74eaac2 100644
--- a/Documentation/filesystems/sysfs-pci.txt
+++ b/Documentation/filesystems/sysfs-pci.txt
@@ -39,7 +39,7 @@ files, each with their own function.
local_cpus nearby CPU mask (cpumask, ro)
remove remove device from kernel's list (ascii, wo)
resource PCI resource host addresses (ascii, ro)
- resource0..N PCI resource N, if present (binary, mmap)
+ resource0..N PCI resource N, if present (binary, mmap, rw[1])
resource0_wc..N_wc PCI WC map resource N, if prefetchable (binary, mmap)
rom PCI ROM resource, if present (binary, ro)
subsystem_device PCI subsystem device (ascii, ro)
@@ -54,13 +54,16 @@ files, each with their own function.
binary - file contains binary data
cpumask - file contains a cpumask type
+[1] rw for RESOURCE_IO (I/O port) regions only
+
The read only files are informational, writes to them will be ignored, with
the exception of the 'rom' file. Writable files can be used to perform
actions on the device (e.g. changing config space, detaching a device).
mmapable files are available via an mmap of the file at offset 0 and can be
used to do actual device programming from userspace. Note that some platforms
don't support mmapping of certain resources, so be sure to check the return
-value from any attempted mmap.
+value from any attempted mmap. The most notable of these are I/O port
+resources, which also provide read/write access.
The 'enable' file provides a counter that indicates how many times the device
has been enabled. If the 'enable' file currently returns '4', and a '1' is
diff --git a/Documentation/filesystems/sysfs.txt b/Documentation/filesystems/sysfs.txt
index 931c806..5d1335fae 100644
--- a/Documentation/filesystems/sysfs.txt
+++ b/Documentation/filesystems/sysfs.txt
@@ -4,7 +4,7 @@ sysfs - _The_ filesystem for exporting kernel objects.
Patrick Mochel <mochel@osdl.org>
Mike Murphy <mamurph@cs.clemson.edu>
-Revised: 22 February 2009
+Revised: 15 July 2010
Original: 10 January 2003
@@ -124,7 +124,7 @@ show and store methods of the attribute owners.
struct sysfs_ops {
ssize_t (*show)(struct kobject *, struct attribute *, char *);
- ssize_t (*store)(struct kobject *, struct attribute *, const char *);
+ ssize_t (*store)(struct kobject *, struct attribute *, const char *, size_t);
};
[ Subsystems should have already defined a struct kobj_type as a
@@ -139,18 +139,22 @@ calls the associated methods.
To illustrate:
+#define to_dev(obj) container_of(obj, struct device, kobj)
#define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr)
-#define to_dev(d) container_of(d, struct device, kobj)
-static ssize_t
-dev_attr_show(struct kobject * kobj, struct attribute * attr, char * buf)
+static ssize_t dev_attr_show(struct kobject *kobj, struct attribute *attr,
+ char *buf)
{
- struct device_attribute * dev_attr = to_dev_attr(attr);
- struct device * dev = to_dev(kobj);
- ssize_t ret = 0;
+ struct device_attribute *dev_attr = to_dev_attr(attr);
+ struct device *dev = to_dev(kobj);
+ ssize_t ret = -EIO;
if (dev_attr->show)
- ret = dev_attr->show(dev, buf);
+ ret = dev_attr->show(dev, dev_attr, buf);
+ if (ret >= (ssize_t)PAGE_SIZE) {
+ print_symbol("dev_attr_show: %s returned bad count\n",
+ (unsigned long)dev_attr->show);
+ }
return ret;
}
@@ -163,10 +167,9 @@ To read or write attributes, show() or store() methods must be
specified when declaring the attribute. The method types should be as
simple as those defined for device attributes:
-ssize_t (*show)(struct device * dev, struct device_attribute * attr,
- char * buf);
-ssize_t (*store)(struct device * dev, struct device_attribute * attr,
- const char * buf);
+ssize_t (*show)(struct device *dev, struct device_attribute *attr, char *buf);
+ssize_t (*store)(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count);
IOW, they should take only an object, an attribute, and a buffer as parameters.
@@ -209,8 +212,8 @@ Other notes:
- show() should always use snprintf().
-- store() should return the number of bytes used from the buffer. This
- can be done using strlen().
+- store() should return the number of bytes used from the buffer. If the
+ entire buffer has been used, just return the count argument.
- show() or store() can always return errors. If a bad value comes
through, be sure to return an error.
@@ -223,15 +226,18 @@ Other notes:
A very simple (and naive) implementation of a device attribute is:
-static ssize_t show_name(struct device *dev, struct device_attribute *attr, char *buf)
+static ssize_t show_name(struct device *dev, struct device_attribute *attr,
+ char *buf)
{
return snprintf(buf, PAGE_SIZE, "%s\n", dev->name);
}
-static ssize_t store_name(struct device * dev, const char * buf)
+static ssize_t store_name(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
{
- sscanf(buf, "%20s", dev->name);
- return strnlen(buf, PAGE_SIZE);
+ snprintf(dev->name, sizeof(dev->name), "%.*s",
+ (int)min(count, sizeof(dev->name) - 1), buf);
+ return count;
}
static DEVICE_ATTR(name, S_IRUGO, show_name, store_name);
@@ -327,7 +333,7 @@ Structure:
struct bus_attribute {
struct attribute attr;
ssize_t (*show)(struct bus_type *, char * buf);
- ssize_t (*store)(struct bus_type *, const char * buf);
+ ssize_t (*store)(struct bus_type *, const char * buf, size_t count);
};
Declaring:
diff --git a/Documentation/firmware_class/hotplug-script b/Documentation/firmware_class/hotplug-script
index 1990130..8143a95 100644
--- a/Documentation/firmware_class/hotplug-script
+++ b/Documentation/firmware_class/hotplug-script
@@ -6,11 +6,12 @@
HOTPLUG_FW_DIR=/usr/lib/hotplug/firmware/
-echo 1 > /sys/$DEVPATH/loading
-cat $HOTPLUG_FW_DIR/$FIRMWARE > /sys/$DEVPATH/data
-echo 0 > /sys/$DEVPATH/loading
-
-# To cancel the load in case of error:
-#
-# echo -1 > /sys/$DEVPATH/loading
-#
+if [ "$SUBSYSTEM" == "firmware" -a "$ACTION" == "add" ]; then
+ if [ -f $HOTPLUG_FW_DIR/$FIRMWARE ]; then
+ echo 1 > /sys/$DEVPATH/loading
+ cat $HOTPLUG_FW_DIR/$FIRMWARE > /sys/$DEVPATH/data
+ echo 0 > /sys/$DEVPATH/loading
+ else
+ echo -1 > /sys/$DEVPATH/loading
+ fi
+fi
diff --git a/Documentation/hwmon/pkgtemp b/Documentation/hwmon/pkgtemp
new file mode 100644
index 0000000..c8e1fb0
--- /dev/null
+++ b/Documentation/hwmon/pkgtemp
@@ -0,0 +1,36 @@
+Kernel driver pkgtemp
+======================
+
+Supported chips:
+ * Intel family
+ Prefix: 'pkgtemp'
+ CPUID:
+ Datasheet: Intel 64 and IA-32 Architectures Software Developer's Manual
+ Volume 3A: System Programming Guide
+
+Author: Fenghua Yu
+
+Description
+-----------
+
+This driver permits reading package level temperature sensor embedded inside
+Intel CPU package. The sensors can be in core, uncore, memory controller, or
+other components in a package. The feature is first implemented in Intel Sandy
+Bridge platform.
+
+Temperature is measured in degrees Celsius and measurement resolution is
+1 degree C. Valid temperatures are from 0 to TjMax degrees C, because the actual
+value of temperature register is in fact a delta from TjMax.
+
+Temperature known as TjMax is the maximum junction temperature of package.
+We get this from MSR_IA32_TEMPERATURE_TARGET. If the MSR is not accessible,
+we define TjMax as 100 degrees Celsius. At this temperature, protection
+mechanism will perform actions to forcibly cool down the package. Alarm
+may be raised, if the temperature grows enough (more than TjMax) to trigger
+the Out-Of-Spec bit. Following table summarizes the exported sysfs files:
+
+temp1_input - Package temperature (in millidegrees Celsius).
+temp1_max - All cooling devices should be turned on.
+temp1_crit - Maximum junction temperature (in millidegrees Celsius).
+temp1_crit_alarm - Set when Out-of-spec bit is set, never clears.
+ Correct CPU operation is no longer guaranteed.
diff --git a/Documentation/kbuild/kbuild.txt b/Documentation/kbuild/kbuild.txt
index 634c625..1e5165a 100644
--- a/Documentation/kbuild/kbuild.txt
+++ b/Documentation/kbuild/kbuild.txt
@@ -22,11 +22,33 @@ building C files and assembler files.
KAFLAGS
--------------------------------------------------
-Additional options to the assembler.
+Additional options to the assembler (for built-in and modules).
+
+AFLAGS_MODULE
+--------------------------------------------------
+Addtional module specific options to use for $(AS).
+
+AFLAGS_KERNEL
+--------------------------------------------------
+Addtional options for $(AS) when used for assembler
+code for code that is compiled as built-in.
KCFLAGS
--------------------------------------------------
-Additional options to the C compiler.
+Additional options to the C compiler (for built-in and modules).
+
+CFLAGS_KERNEL
+--------------------------------------------------
+Addtional options for $(CC) when used to compile
+code that is compiled as built-in.
+
+CFLAGS_MODULE
+--------------------------------------------------
+Addtional module specific options to use for $(CC).
+
+LDFLAGS_MODULE
+--------------------------------------------------
+Additional options used for $(LD) when linking modules.
KBUILD_VERBOSE
--------------------------------------------------
@@ -40,15 +62,15 @@ Set the directory to look for the kernel source when building external
modules.
The directory can be specified in several ways:
1) Use "M=..." on the command line
-2) Environmnet variable KBUILD_EXTMOD
-3) Environmnet variable SUBDIRS
+2) Environment variable KBUILD_EXTMOD
+3) Environment variable SUBDIRS
The possibilities are listed in the order they take precedence.
Using "M=..." will always override the others.
KBUILD_OUTPUT
--------------------------------------------------
Specify the output directory when building the kernel.
-The output directory can also be specificed using "O=...".
+The output directory can also be specified using "O=...".
Setting "O=..." takes precedence over KBUILD_OUTPUT.
ARCH
@@ -90,7 +112,7 @@ The script will be called with the following arguments:
$3 - kernel map file
$4 - default install path (use root directory if blank)
-The implmentation of "make install" is architecture specific
+The implementation of "make install" is architecture specific
and it may differ from the above.
INSTALLKERNEL is provided to enable the possibility to
diff --git a/Documentation/kbuild/kconfig.txt b/Documentation/kbuild/kconfig.txt
index b2cb16e..cca46b1 100644
--- a/Documentation/kbuild/kconfig.txt
+++ b/Documentation/kbuild/kconfig.txt
@@ -65,7 +65,7 @@ also use the environment variable KCONFIG_ALLCONFIG as a flag or a
filename that contains config symbols that the user requires to be
set to a specific value. If KCONFIG_ALLCONFIG is used without a
filename, "make *config" checks for a file named
-"all{yes/mod/no/random}.config" (corresponding to the *config command
+"all{yes/mod/no/def/random}.config" (corresponding to the *config command
that was used) for symbol values that are to be forced. If this file
is not found, it checks for a file named "all.config" to contain forced
values.
diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt
index 71c602d..c375313 100644
--- a/Documentation/kbuild/makefiles.txt
+++ b/Documentation/kbuild/makefiles.txt
@@ -168,7 +168,7 @@ more details, with real examples.
#drivers/isdn/i4l/Makefile
# Makefile for the kernel ISDN subsystem and device drivers.
# Each configuration option enables a list of files.
- obj-$(CONFIG_ISDN) += isdn.o
+ obj-$(CONFIG_ISDN_I4L) += isdn.o
obj-$(CONFIG_ISDN_PPP_BSDCOMP) += isdn_bsdcomp.o
--- 3.3 Loadable module goals - obj-m
@@ -187,34 +187,35 @@ more details, with real examples.
Note: In this example $(CONFIG_ISDN_PPP_BSDCOMP) evaluates to 'm'
If a kernel module is built from several source files, you specify
- that you want to build a module in the same way as above.
-
- Kbuild needs to know which the parts that you want to build your
- module from, so you have to tell it by setting an
- $(<module_name>-objs) variable.
+ that you want to build a module in the same way as above; however,
+ kbuild needs to know which object files you want to build your
+ module from, so you have to tell it by setting a $(<module_name>-y)
+ variable.
Example:
#drivers/isdn/i4l/Makefile
- obj-$(CONFIG_ISDN) += isdn.o
- isdn-objs := isdn_net_lib.o isdn_v110.o isdn_common.o
+ obj-$(CONFIG_ISDN_I4L) += isdn.o
+ isdn-y := isdn_net_lib.o isdn_v110.o isdn_common.o
In this example, the module name will be isdn.o. Kbuild will
- compile the objects listed in $(isdn-objs) and then run
+ compile the objects listed in $(isdn-y) and then run
"$(LD) -r" on the list of these files to generate isdn.o.
- Kbuild recognises objects used for composite objects by the suffix
- -objs, and the suffix -y. This allows the Makefiles to use
- the value of a CONFIG_ symbol to determine if an object is part
- of a composite object.
+ Due to kbuild recognizing $(<module_name>-y) for composite objects,
+ you can use the value of a CONFIG_ symbol to optionally include an
+ object file as part of a composite object.
Example:
#fs/ext2/Makefile
- obj-$(CONFIG_EXT2_FS) += ext2.o
- ext2-y := balloc.o bitmap.o
- ext2-$(CONFIG_EXT2_FS_XATTR) += xattr.o
+ obj-$(CONFIG_EXT2_FS) += ext2.o
+ ext2-y := balloc.o dir.o file.o ialloc.o inode.o ioctl.o \
+ namei.o super.o symlink.o
+ ext2-$(CONFIG_EXT2_FS_XATTR) += xattr.o xattr_user.o \
+ xattr_trusted.o
- In this example, xattr.o is only part of the composite object
- ext2.o if $(CONFIG_EXT2_FS_XATTR) evaluates to 'y'.
+ In this example, xattr.o, xattr_user.o and xattr_trusted.o are only
+ part of the composite object ext2.o if $(CONFIG_EXT2_FS_XATTR)
+ evaluates to 'y'.
Note: Of course, when you are building objects into the kernel,
the syntax above will also work. So, if you have CONFIG_EXT2_FS=y,
@@ -244,12 +245,12 @@ more details, with real examples.
may contain both a built-in.o and a lib.a file.
Example:
- #arch/i386/lib/Makefile
- lib-y := checksum.o delay.o
+ #arch/x86/lib/Makefile
+ lib-y := delay.o
- This will create a library lib.a based on checksum.o and delay.o.
- For kbuild to actually recognize that there is a lib.a being built,
- the directory shall be listed in libs-y.
+ This will create a library lib.a based on delay.o. For kbuild to
+ actually recognize that there is a lib.a being built, the directory
+ shall be listed in libs-y.
See also "6.3 List directories to visit when descending".
Use of lib-y is normally restricted to lib/ and arch/*/lib.
@@ -284,43 +285,40 @@ more details, with real examples.
--- 3.7 Compilation flags
ccflags-y, asflags-y and ldflags-y
- The three flags listed above applies only to the kbuild makefile
- where they are assigned. They are used for all the normal
- cc, as and ld invocation happenign during a recursive build.
+ These three flags apply only to the kbuild makefile in which they
+ are assigned. They are used for all the normal cc, as and ld
+ invocations happening during a recursive build.
Note: Flags with the same behaviour were previously named:
EXTRA_CFLAGS, EXTRA_AFLAGS and EXTRA_LDFLAGS.
- They are yet supported but their use are deprecated.
+ They are still supported but their usage is deprecated.
- ccflags-y specifies options for compiling C files with $(CC).
+ ccflags-y specifies options for compiling with $(CC).
Example:
- # drivers/sound/emu10k1/Makefile
- ccflags-y += -I$(obj)
- ccflags-$(DEBUG) += -DEMU10K1_DEBUG
-
+ # drivers/acpi/Makefile
+ ccflags-y := -Os
+ ccflags-$(CONFIG_ACPI_DEBUG) += -DACPI_DEBUG_OUTPUT
This variable is necessary because the top Makefile owns the
variable $(KBUILD_CFLAGS) and uses it for compilation flags for the
entire tree.
- asflags-y is a similar string for per-directory options
- when compiling assembly language source.
+ asflags-y specifies options for assembling with $(AS).
Example:
- #arch/x86_64/kernel/Makefile
- asflags-y := -traditional
-
+ #arch/sparc/kernel/Makefile
+ asflags-y := -ansi
- ldflags-y is a string for per-directory options to $(LD).
+ ldflags-y specifies options for linking with $(LD).
Example:
- #arch/m68k/fpsp040/Makefile
- ldflags-y := -x
+ #arch/cris/boot/compressed/Makefile
+ ldflags-y += -T $(srctree)/$(src)/decompress_$(arch-y).lds
subdir-ccflags-y, subdir-asflags-y
- The two flags listed above are similar to ccflags-y and as-falgs-y.
- The difference is that the subdir- variants has effect for the kbuild
- file where tey are present and all subdirectories.
+ The two flags listed above are similar to ccflags-y and asflags-y.
+ The difference is that the subdir- variants have effect for the kbuild
+ file where they are present and all subdirectories.
Options specified using subdir-* are added to the commandline before
the options specified using the non-subdir variants.
@@ -340,18 +338,18 @@ more details, with real examples.
CFLAGS_aha152x.o = -DAHA152X_STAT -DAUTOCONF
CFLAGS_gdth.o = # -DDEBUG_GDTH=2 -D__SERIAL__ -D__COM2__ \
-DGDTH_STATISTICS
- CFLAGS_seagate.o = -DARBITRATE -DPARITY -DSEAGATE_USE_ASM
- These three lines specify compilation flags for aha152x.o,
- gdth.o, and seagate.o
+ These two lines specify compilation flags for aha152x.o and gdth.o.
$(AFLAGS_$@) is a similar feature for source files in assembly
languages.
Example:
# arch/arm/kernel/Makefile
- AFLAGS_head-armv.o := -DTEXTADDR=$(TEXTADDR) -traditional
- AFLAGS_head-armo.o := -DTEXTADDR=$(TEXTADDR) -traditional
+ AFLAGS_head.o := -DTEXT_OFFSET=$(TEXT_OFFSET)
+ AFLAGS_crunch-bits.o := -Wa,-mcpu=ep9312
+ AFLAGS_iwmmxt.o := -Wa,-mcpu=iwmmxt
+
--- 3.9 Dependency tracking
@@ -923,16 +921,33 @@ When kbuild executes, the following steps are followed (roughly):
The first example utilises the trick that a config option expands
to 'y' when selected.
- CFLAGS_KERNEL $(CC) options specific for built-in
+ KBUILD_AFLAGS_KERNEL $(AS) options specific for built-in
+
+ $(KBUILD_AFLAGS_KERNEL) contains extra C compiler flags used to compile
+ resident kernel code.
+
+ KBUILD_AFLAGS_MODULE Options for $(AS) when building modules
+
+ $(KBUILD_AFLAGS_MODULE) is used to add arch specific options that
+ are used for $(AS).
+ From commandline AFLAGS_MODULE shall be used (see kbuild.txt).
- $(CFLAGS_KERNEL) contains extra C compiler flags used to compile
+ KBUILD_CFLAGS_KERNEL $(CC) options specific for built-in
+
+ $(KBUILD_CFLAGS_KERNEL) contains extra C compiler flags used to compile
resident kernel code.
- CFLAGS_MODULE $(CC) options specific for modules
+ KBUILD_CFLAGS_MODULE Options for $(CC) when building modules
+
+ $(KBUILD_CFLAGS_MODULE) is used to add arch specific options that
+ are used for $(CC).
+ From commandline CFLAGS_MODULE shall be used (see kbuild.txt).
- $(CFLAGS_MODULE) contains extra C compiler flags used to compile code
- for loadable kernel modules.
+ KBUILD_LDFLAGS_MODULE Options for $(LD) when linking modules
+ $(KBUILD_LDFLAGS_MODULE) is used to add arch specific options
+ used when linking modules. This is often a linker script.
+ From commandline LDFLAGS_MODULE shall be used (see kbuild.txt).
--- 6.2 Add prerequisites to archprepare:
@@ -1176,14 +1191,14 @@ When kbuild executes, the following steps are followed (roughly):
=== 7 Kbuild syntax for exported headers
The kernel include a set of headers that is exported to userspace.
-Many headers can be exported as-is but other headers requires a
+Many headers can be exported as-is but other headers require a
minimal pre-processing before they are ready for user-space.
The pre-processing does:
- drop kernel specific annotations
- drop include of compiler.h
-- drop all sections that is kernel internat (guarded by ifdef __KERNEL__)
+- drop all sections that are kernel internal (guarded by ifdef __KERNEL__)
-Each relevant directory contain a file name "Kbuild" which specify the
+Each relevant directory contains a file name "Kbuild" which specifies the
headers to be exported.
See subsequent chapter for the syntax of the Kbuild file.
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index d9239d5..71d2863 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -73,7 +73,6 @@ parameter is applicable:
MTD MTD (Memory Technology Device) support is enabled.
NET Appropriate network support is enabled.
NUMA NUMA support is enabled.
- GENERIC_TIME The generic timeofday code is enabled.
NFS Appropriate NFS support is enabled.
OSS OSS sound support is enabled.
PV_OPS A paravirtualized kernel is enabled.
@@ -116,6 +115,7 @@ parameter is applicable:
More X86-64 boot options can be found in
Documentation/x86/x86_64/boot-options.txt .
X86 Either 32bit or 64bit x86 (same as X86-32+X86-64)
+ XEN Xen support is enabled
In addition, the following text indicates that the option:
@@ -469,7 +469,7 @@ and is between 256 and 4096 characters. It is defined in the file
clocksource is not available, it defaults to PIT.
Format: { pit | tsc | cyclone | pmtmr }
- clocksource= [GENERIC_TIME] Override the default clocksource
+ clocksource= Override the default clocksource
Format: <string>
Override the default clocksource and use the clocksource
with the name specified.
@@ -1144,9 +1144,12 @@ and is between 256 and 4096 characters. It is defined in the file
kgdboc= [KGDB,HW] kgdb over consoles.
Requires a tty driver that supports console polling,
or a supported polling keyboard driver (non-usb).
- Serial only format: <serial_device>[,baud]
- keyboard only format: kbd
- keyboard and serial format: kbd,<serial_device>[,baud]
+ Serial only format: <serial_device>[,baud]
+ keyboard only format: kbd
+ keyboard and serial format: kbd,<serial_device>[,baud]
+ Optional Kernel mode setting:
+ kms, kbd format: kms,kbd
+ kms, kbd and serial format: kms,kbd,<ser_dev>[,baud]
kgdbwait [KGDB] Stop kernel execution and enter the
kernel debugger at the earliest opportunity.
@@ -1812,6 +1815,8 @@ and is between 256 and 4096 characters. It is defined in the file
nousb [USB] Disable the USB subsystem
+ nowatchdog [KNL] Disable the lockup detector.
+
nowb [ARM]
nox2apic [X86-64,APIC] Do not enable x2APIC mode.
@@ -1970,6 +1975,8 @@ and is between 256 and 4096 characters. It is defined in the file
norom [X86] Do not assign address space to
expansion ROMs that do not already have
BIOS assigned address ranges.
+ nobar [X86] Do not assign address space to the
+ BARs that weren't assigned by the BIOS.
irqmask=0xMMMM [X86] Set a bit mask of IRQs allowed to be
assigned automatically to PCI devices. You can
make the kernel exclude IRQs of your ISA cards
@@ -2886,6 +2893,16 @@ and is between 256 and 4096 characters. It is defined in the file
xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks.
xd_geo= See header of drivers/block/xd.c.
+ xen_emul_unplug= [HW,X86,XEN]
+ Unplug Xen emulated devices
+ Format: [unplug0,][unplug1]
+ ide-disks -- unplug primary master IDE devices
+ aux-ide-disks -- unplug non-primary-master IDE devices
+ nics -- unplug network devices
+ all -- unplug all emulated devices (NICs and IDE disks)
+ ignore -- continue loading the Xen platform PCI driver even
+ if the version check failed
+
xirc2ps_cs= [NET,PCMCIA]
Format:
<irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
diff --git a/Documentation/pcmcia/driver-changes.txt b/Documentation/pcmcia/driver-changes.txt
index 61bc4e9..26c0f9c 100644
--- a/Documentation/pcmcia/driver-changes.txt
+++ b/Documentation/pcmcia/driver-changes.txt
@@ -1,4 +1,16 @@
This file details changes in 2.6 which affect PCMCIA card driver authors:
+* pcmcia_request_io changes (as of 2.6.36)
+ Instead of io_req_t, drivers are now requested to fill out
+ struct pcmcia_device *p_dev->resource[0,1] for up to two ioport
+ ranges. After a call to pcmcia_request_io(), the ports found there
+ are reserved, after calling pcmcia_request_configuration(), they may
+ be used.
+
+* No dev_info_t, no cs_types.h (as of 2.6.36)
+ dev_info_t and a few other typedefs are removed. No longer use them
+ in PCMCIA device drivers. Also, do not include pcmcia/cs_types.h, as
+ this file is gone.
+
* No dev_node_t (as of 2.6.35)
There is no more need to fill out a "dev_node_t" structure.
diff --git a/Documentation/slow-work.txt b/Documentation/slow-work.txt
deleted file mode 100644
index 9dbf4470c..0000000
--- a/Documentation/slow-work.txt
+++ /dev/null
@@ -1,322 +0,0 @@
- ====================================
- SLOW WORK ITEM EXECUTION THREAD POOL
- ====================================
-
-By: David Howells <dhowells@redhat.com>
-
-The slow work item execution thread pool is a pool of threads for performing
-things that take a relatively long time, such as making mkdir calls.
-Typically, when processing something, these items will spend a lot of time
-blocking a thread on I/O, thus making that thread unavailable for doing other
-work.
-
-The standard workqueue model is unsuitable for this class of work item as that
-limits the owner to a single thread or a single thread per CPU. For some
-tasks, however, more threads - or fewer - are required.
-
-There is just one pool per system. It contains no threads unless something
-wants to use it - and that something must register its interest first. When
-the pool is active, the number of threads it contains is dynamic, varying
-between a maximum and minimum setting, depending on the load.
-
-
-====================
-CLASSES OF WORK ITEM
-====================
-
-This pool support two classes of work items:
-
- (*) Slow work items.
-
- (*) Very slow work items.
-
-The former are expected to finish much quicker than the latter.
-
-An operation of the very slow class may do a batch combination of several
-lookups, mkdirs, and a create for instance.
-
-An operation of the ordinarily slow class may, for example, write stuff or
-expand files, provided the time taken to do so isn't too long.
-
-Operations of both types may sleep during execution, thus tying up the thread
-loaned to it.
-
-A further class of work item is available, based on the slow work item class:
-
- (*) Delayed slow work items.
-
-These are slow work items that have a timer to defer queueing of the item for
-a while.
-
-
-THREAD-TO-CLASS ALLOCATION
---------------------------
-
-Not all the threads in the pool are available to work on very slow work items.
-The number will be between one and one fewer than the number of active threads.
-This is configurable (see the "Pool Configuration" section).
-
-All the threads are available to work on ordinarily slow work items, but a
-percentage of the threads will prefer to work on very slow work items.
-
-The configuration ensures that at least one thread will be available to work on
-very slow work items, and at least one thread will be available that won't work
-on very slow work items at all.
-
-
-=====================
-USING SLOW WORK ITEMS
-=====================
-
-Firstly, a module or subsystem wanting to make use of slow work items must
-register its interest:
-
- int ret = slow_work_register_user(struct module *module);
-
-This will return 0 if successful, or a -ve error upon failure. The module
-pointer should be the module interested in using this facility (almost
-certainly THIS_MODULE).
-
-
-Slow work items may then be set up by:
-
- (1) Declaring a slow_work struct type variable:
-
- #include <linux/slow-work.h>
-
- struct slow_work myitem;
-
- (2) Declaring the operations to be used for this item:
-
- struct slow_work_ops myitem_ops = {
- .get_ref = myitem_get_ref,
- .put_ref = myitem_put_ref,
- .execute = myitem_execute,
- };
-
- [*] For a description of the ops, see section "Item Operations".
-
- (3) Initialising the item:
-
- slow_work_init(&myitem, &myitem_ops);
-
- or:
-
- delayed_slow_work_init(&myitem, &myitem_ops);
-
- or:
-
- vslow_work_init(&myitem, &myitem_ops);
-
- depending on its class.
-
-A suitably set up work item can then be enqueued for processing:
-
- int ret = slow_work_enqueue(&myitem);
-
-This will return a -ve error if the thread pool is unable to gain a reference
-on the item, 0 otherwise, or (for delayed work):
-
- int ret = delayed_slow_work_enqueue(&myitem, my_jiffy_delay);
-
-
-The items are reference counted, so there ought to be no need for a flush
-operation. But as the reference counting is optional, means to cancel
-existing work items are also included:
-
- cancel_slow_work(&myitem);
- cancel_delayed_slow_work(&myitem);
-
-can be used to cancel pending work. The above cancel function waits for
-existing work to have been executed (or prevent execution of them, depending
-on timing).
-
-
-When all a module's slow work items have been processed, and the
-module has no further interest in the facility, it should unregister its
-interest:
-
- slow_work_unregister_user(struct module *module);
-
-The module pointer is used to wait for all outstanding work items for that
-module before completing the unregistration. This prevents the put_ref() code
-from being taken away before it completes. module should almost certainly be
-THIS_MODULE.
-
-
-================
-HELPER FUNCTIONS
-================
-
-The slow-work facility provides a function by which it can be determined
-whether or not an item is queued for later execution:
-
- bool queued = slow_work_is_queued(struct slow_work *work);
-
-If it returns false, then the item is not on the queue (it may be executing
-with a requeue pending). This can be used to work out whether an item on which
-another depends is on the queue, thus allowing a dependent item to be queued
-after it.
-
-If the above shows an item on which another depends not to be queued, then the
-owner of the dependent item might need to wait. However, to avoid locking up
-the threads unnecessarily be sleeping in them, it can make sense under some
-circumstances to return the work item to the queue, thus deferring it until
-some other items have had a chance to make use of the yielded thread.
-
-To yield a thread and defer an item, the work function should simply enqueue
-the work item again and return. However, this doesn't work if there's nothing
-actually on the queue, as the thread just vacated will jump straight back into
-the item's work function, thus busy waiting on a CPU.
-
-Instead, the item should use the thread to wait for the dependency to go away,
-but rather than using schedule() or schedule_timeout() to sleep, it should use
-the following function:
-
- bool requeue = slow_work_sleep_till_thread_needed(
- struct slow_work *work,
- signed long *_timeout);
-
-This will add a second wait and then sleep, such that it will be woken up if
-either something appears on the queue that could usefully make use of the
-thread - and behind which this item can be queued, or if the event the caller
-set up to wait for happens. True will be returned if something else appeared
-on the queue and this work function should perhaps return, of false if
-something else woke it up. The timeout is as for schedule_timeout().
-
-For example:
-
- wq = bit_waitqueue(&my_flags, MY_BIT);
- init_wait(&wait);
- requeue = false;
- do {
- prepare_to_wait(wq, &wait, TASK_UNINTERRUPTIBLE);
- if (!test_bit(MY_BIT, &my_flags))
- break;
- requeue = slow_work_sleep_till_thread_needed(&my_work,
- &timeout);
- } while (timeout > 0 && !requeue);
- finish_wait(wq, &wait);
- if (!test_bit(MY_BIT, &my_flags)
- goto do_my_thing;
- if (requeue)
- return; // to slow_work
-
-
-===============
-ITEM OPERATIONS
-===============
-
-Each work item requires a table of operations of type struct slow_work_ops.
-Only ->execute() is required; the getting and putting of a reference and the
-describing of an item are all optional.
-
- (*) Get a reference on an item:
-
- int (*get_ref)(struct slow_work *work);
-
- This allows the thread pool to attempt to pin an item by getting a
- reference on it. This function should return 0 if the reference was
- granted, or a -ve error otherwise. If an error is returned,
- slow_work_enqueue() will fail.
-
- The reference is held whilst the item is queued and whilst it is being
- executed. The item may then be requeued with the same reference held, or
- the reference will be released.
-
- (*) Release a reference on an item:
-
- void (*put_ref)(struct slow_work *work);
-
- This allows the thread pool to unpin an item by releasing the reference on
- it. The thread pool will not touch the item again once this has been
- called.
-
- (*) Execute an item:
-
- void (*execute)(struct slow_work *work);
-
- This should perform the work required of the item. It may sleep, it may
- perform disk I/O and it may wait for locks.
-
- (*) View an item through /proc:
-
- void (*desc)(struct slow_work *work, struct seq_file *m);
-
- If supplied, this should print to 'm' a small string describing the work
- the item is to do. This should be no more than about 40 characters, and
- shouldn't include a newline character.
-
- See the 'Viewing executing and queued items' section below.
-
-
-==================
-POOL CONFIGURATION
-==================
-
-The slow-work thread pool has a number of configurables:
-
- (*) /proc/sys/kernel/slow-work/min-threads
-
- The minimum number of threads that should be in the pool whilst it is in
- use. This may be anywhere between 2 and max-threads.
-
- (*) /proc/sys/kernel/slow-work/max-threads
-
- The maximum number of threads that should in the pool. This may be
- anywhere between min-threads and 255 or NR_CPUS * 2, whichever is greater.
-
- (*) /proc/sys/kernel/slow-work/vslow-percentage
-
- The percentage of active threads in the pool that may be used to execute
- very slow work items. This may be between 1 and 99. The resultant number
- is bounded to between 1 and one fewer than the number of active threads.
- This ensures there is always at least one thread that can process very
- slow work items, and always at least one thread that won't.
-
-
-==================================
-VIEWING EXECUTING AND QUEUED ITEMS
-==================================
-
-If CONFIG_SLOW_WORK_DEBUG is enabled, a debugfs file is made available:
-
- /sys/kernel/debug/slow_work/runqueue
-
-through which the list of work items being executed and the queues of items to
-be executed may be viewed. The owner of a work item is given the chance to
-add some information of its own.
-
-The contents look something like the following:
-
- THR PID ITEM ADDR FL MARK DESC
- === ===== ================ == ===== ==========
- 0 3005 ffff880023f52348 a 952ms FSC: OBJ17d3: LOOK
- 1 3006 ffff880024e33668 2 160ms FSC: OBJ17e5 OP60d3b: Write1/Store fl=2
- 2 3165 ffff8800296dd180 a 424ms FSC: OBJ17e4: LOOK
- 3 4089 ffff8800262c8d78 a 212ms FSC: OBJ17ea: CRTN
- 4 4090 ffff88002792bed8 2 388ms FSC: OBJ17e8 OP60d36: Write1/Store fl=2
- 5 4092 ffff88002a0ef308 2 388ms FSC: OBJ17e7 OP60d2e: Write1/Store fl=2
- 6 4094 ffff88002abaf4b8 2 132ms FSC: OBJ17e2 OP60d4e: Write1/Store fl=2
- 7 4095 ffff88002bb188e0 a 388ms FSC: OBJ17e9: CRTN
- vsq - ffff880023d99668 1 308ms FSC: OBJ17e0 OP60f91: Write1/EnQ fl=2
- vsq - ffff8800295d1740 1 212ms FSC: OBJ16be OP4d4b6: Write1/EnQ fl=2
- vsq - ffff880025ba3308 1 160ms FSC: OBJ179a OP58dec: Write1/EnQ fl=2
- vsq - ffff880024ec83e0 1 160ms FSC: OBJ17ae OP599f2: Write1/EnQ fl=2
- vsq - ffff880026618e00 1 160ms FSC: OBJ17e6 OP60d33: Write1/EnQ fl=2
- vsq - ffff880025a2a4b8 1 132ms FSC: OBJ16a2 OP4d583: Write1/EnQ fl=2
- vsq - ffff880023cbe6d8 9 212ms FSC: OBJ17eb: LOOK
- vsq - ffff880024d37590 9 212ms FSC: OBJ17ec: LOOK
- vsq - ffff880027746cb0 9 212ms FSC: OBJ17ed: LOOK
- vsq - ffff880024d37ae8 9 212ms FSC: OBJ17ee: LOOK
- vsq - ffff880024d37cb0 9 212ms FSC: OBJ17ef: LOOK
- vsq - ffff880025036550 9 212ms FSC: OBJ17f0: LOOK
- vsq - ffff8800250368e0 9 212ms FSC: OBJ17f1: LOOK
- vsq - ffff880025036aa8 9 212ms FSC: OBJ17f2: LOOK
-
-In the 'THR' column, executing items show the thread they're occupying and
-queued threads indicate which queue they're on. 'PID' shows the process ID of
-a slow-work thread that's executing something. 'FL' shows the work item flags.
-'MARK' indicates how long since an item was queued or began executing. Lastly,
-the 'DESC' column permits the owner of an item to give some information.
-
diff --git a/Documentation/timers/timers-howto.txt b/Documentation/timers/timers-howto.txt
new file mode 100644
index 0000000..c9ef29d
--- /dev/null
+++ b/Documentation/timers/timers-howto.txt
@@ -0,0 +1,105 @@
+delays - Information on the various kernel delay / sleep mechanisms
+-------------------------------------------------------------------
+
+This document seeks to answer the common question: "What is the
+RightWay (TM) to insert a delay?"
+
+This question is most often faced by driver writers who have to
+deal with hardware delays and who may not be the most intimately
+familiar with the inner workings of the Linux Kernel.
+
+
+Inserting Delays
+----------------
+
+The first, and most important, question you need to ask is "Is my
+code in an atomic context?" This should be followed closely by "Does
+it really need to delay in atomic context?" If so...
+
+ATOMIC CONTEXT:
+ You must use the *delay family of functions. These
+ functions use the jiffie estimation of clock speed
+ and will busy wait for enough loop cycles to achieve
+ the desired delay:
+
+ ndelay(unsigned long nsecs)
+ udelay(unsigned long usecs)
+ mdelay(unsgined long msecs)
+
+ udelay is the generally preferred API; ndelay-level
+ precision may not actually exist on many non-PC devices.
+
+ mdelay is macro wrapper around udelay, to account for
+ possible overflow when passing large arguments to udelay.
+ In general, use of mdelay is discouraged and code should
+ be refactored to allow for the use of msleep.
+
+NON-ATOMIC CONTEXT:
+ You should use the *sleep[_range] family of functions.
+ There are a few more options here, while any of them may
+ work correctly, using the "right" sleep function will
+ help the scheduler, power management, and just make your
+ driver better :)
+
+ -- Backed by busy-wait loop:
+ udelay(unsigned long usecs)
+ -- Backed by hrtimers:
+ usleep_range(unsigned long min, unsigned long max)
+ -- Backed by jiffies / legacy_timers
+ msleep(unsigned long msecs)
+ msleep_interruptible(unsigned long msecs)
+
+ Unlike the *delay family, the underlying mechanism
+ driving each of these calls varies, thus there are
+ quirks you should be aware of.
+
+
+ SLEEPING FOR "A FEW" USECS ( < ~10us? ):
+ * Use udelay
+
+ - Why not usleep?
+ On slower systems, (embedded, OR perhaps a speed-
+ stepped PC!) the overhead of setting up the hrtimers
+ for usleep *may* not be worth it. Such an evaluation
+ will obviously depend on your specific situation, but
+ it is something to be aware of.
+
+ SLEEPING FOR ~USECS OR SMALL MSECS ( 10us - 20ms):
+ * Use usleep_range
+
+ - Why not msleep for (1ms - 20ms)?
+ Explained originally here:
+ http://lkml.org/lkml/2007/8/3/250
+ msleep(1~20) may not do what the caller intends, and
+ will often sleep longer (~20 ms actual sleep for any
+ value given in the 1~20ms range). In many cases this
+ is not the desired behavior.
+
+ - Why is there no "usleep" / What is a good range?
+ Since usleep_range is built on top of hrtimers, the
+ wakeup will be very precise (ish), thus a simple
+ usleep function would likely introduce a large number
+ of undesired interrupts.
+
+ With the introduction of a range, the scheduler is
+ free to coalesce your wakeup with any other wakeup
+ that may have happened for other reasons, or at the
+ worst case, fire an interrupt for your upper bound.
+
+ The larger a range you supply, the greater a chance
+ that you will not trigger an interrupt; this should
+ be balanced with what is an acceptable upper bound on
+ delay / performance for your specific code path. Exact
+ tolerances here are very situation specific, thus it
+ is left to the caller to determine a reasonable range.
+
+ SLEEPING FOR LARGER MSECS ( 10ms+ )
+ * Use msleep or possibly msleep_interruptible
+
+ - What's the difference?
+ msleep sets the current task to TASK_UNINTERRUPTIBLE
+ whereas msleep_interruptible sets the current task to
+ TASK_INTERRUPTIBLE before scheduling the sleep. In
+ short, the difference is whether the sleep can be ended
+ early by a signal. In general, just use msleep unless
+ you know you have a need for the interruptible variant.
diff --git a/Documentation/trace/ftrace-design.txt b/Documentation/trace/ftrace-design.txt
index f1f81af..dc52bd4 100644
--- a/Documentation/trace/ftrace-design.txt
+++ b/Documentation/trace/ftrace-design.txt
@@ -13,6 +13,9 @@ Note that this focuses on architecture implementation details only. If you
want more explanation of a feature in terms of common code, review the common
ftrace.txt file.
+Ideally, everyone who wishes to retain performance while supporting tracing in
+their kernel should make it all the way to dynamic ftrace support.
+
Prerequisites
-------------
@@ -215,7 +218,7 @@ An arch may pass in a unique value (frame pointer) to both the entering and
exiting of a function. On exit, the value is compared and if it does not
match, then it will panic the kernel. This is largely a sanity check for bad
code generation with gcc. If gcc for your port sanely updates the frame
-pointer under different opitmization levels, then ignore this option.
+pointer under different optimization levels, then ignore this option.
However, adding support for it isn't terribly difficult. In your assembly code
that calls prepare_ftrace_return(), pass the frame pointer as the 3rd argument.
@@ -234,7 +237,7 @@ If you can't trace NMI functions, then skip this option.
HAVE_SYSCALL_TRACEPOINTS
----------------------
+------------------------
You need very few things to get the syscalls tracing in an arch.
@@ -250,12 +253,152 @@ You need very few things to get the syscalls tracing in an arch.
HAVE_FTRACE_MCOUNT_RECORD
-------------------------
-See scripts/recordmcount.pl for more info.
+See scripts/recordmcount.pl for more info. Just fill in the arch-specific
+details for how to locate the addresses of mcount call sites via objdump.
+This option doesn't make much sense without also implementing dynamic ftrace.
+
+HAVE_DYNAMIC_FTRACE
+-------------------
+
+You will first need HAVE_FTRACE_MCOUNT_RECORD and HAVE_FUNCTION_TRACER, so
+scroll your reader back up if you got over eager.
+
+Once those are out of the way, you will need to implement:
+ - asm/ftrace.h:
+ - MCOUNT_ADDR
+ - ftrace_call_adjust()
+ - struct dyn_arch_ftrace{}
+ - asm code:
+ - mcount() (new stub)
+ - ftrace_caller()
+ - ftrace_call()
+ - ftrace_stub()
+ - C code:
+ - ftrace_dyn_arch_init()
+ - ftrace_make_nop()
+ - ftrace_make_call()
+ - ftrace_update_ftrace_func()
+
+First you will need to fill out some arch details in your asm/ftrace.h.
+
+Define MCOUNT_ADDR as the address of your mcount symbol similar to:
+ #define MCOUNT_ADDR ((unsigned long)mcount)
+Since no one else will have a decl for that function, you will need to:
+ extern void mcount(void);
+
+You will also need the helper function ftrace_call_adjust(). Most people
+will be able to stub it out like so:
+ static inline unsigned long ftrace_call_adjust(unsigned long addr)
+ {
+ return addr;
+ }
<details to be filled>
+Lastly you will need the custom dyn_arch_ftrace structure. If you need
+some extra state when runtime patching arbitrary call sites, this is the
+place. For now though, create an empty struct:
+ struct dyn_arch_ftrace {
+ /* No extra data needed */
+ };
+
+With the header out of the way, we can fill out the assembly code. While we
+did already create a mcount() function earlier, dynamic ftrace only wants a
+stub function. This is because the mcount() will only be used during boot
+and then all references to it will be patched out never to return. Instead,
+the guts of the old mcount() will be used to create a new ftrace_caller()
+function. Because the two are hard to merge, it will most likely be a lot
+easier to have two separate definitions split up by #ifdefs. Same goes for
+the ftrace_stub() as that will now be inlined in ftrace_caller().
+
+Before we get confused anymore, let's check out some pseudo code so you can
+implement your own stuff in assembly:
-HAVE_DYNAMIC_FTRACE
----------------------
+void mcount(void)
+{
+ return;
+}
+
+void ftrace_caller(void)
+{
+ /* implement HAVE_FUNCTION_TRACE_MCOUNT_TEST if you desire */
+
+ /* save all state needed by the ABI (see paragraph above) */
+
+ unsigned long frompc = ...;
+ unsigned long selfpc = <return address> - MCOUNT_INSN_SIZE;
+
+ftrace_call:
+ ftrace_stub(frompc, selfpc);
+
+ /* restore all state needed by the ABI */
+
+ftrace_stub:
+ return;
+}
+
+This might look a little odd at first, but keep in mind that we will be runtime
+patching multiple things. First, only functions that we actually want to trace
+will be patched to call ftrace_caller(). Second, since we only have one tracer
+active at a time, we will patch the ftrace_caller() function itself to call the
+specific tracer in question. That is the point of the ftrace_call label.
+
+With that in mind, let's move on to the C code that will actually be doing the
+runtime patching. You'll need a little knowledge of your arch's opcodes in
+order to make it through the next section.
+
+Every arch has an init callback function. If you need to do something early on
+to initialize some state, this is the time to do that. Otherwise, this simple
+function below should be sufficient for most people:
+
+int __init ftrace_dyn_arch_init(void *data)
+{
+ /* return value is done indirectly via data */
+ *(unsigned long *)data = 0;
+
+ return 0;
+}
+
+There are two functions that are used to do runtime patching of arbitrary
+functions. The first is used to turn the mcount call site into a nop (which
+is what helps us retain runtime performance when not tracing). The second is
+used to turn the mcount call site into a call to an arbitrary location (but
+typically that is ftracer_caller()). See the general function definition in
+linux/ftrace.h for the functions:
+ ftrace_make_nop()
+ ftrace_make_call()
+The rec->ip value is the address of the mcount call site that was collected
+by the scripts/recordmcount.pl during build time.
+
+The last function is used to do runtime patching of the active tracer. This
+will be modifying the assembly code at the location of the ftrace_call symbol
+inside of the ftrace_caller() function. So you should have sufficient padding
+at that location to support the new function calls you'll be inserting. Some
+people will be using a "call" type instruction while others will be using a
+"branch" type instruction. Specifically, the function is:
+ ftrace_update_ftrace_func()
+
+
+HAVE_DYNAMIC_FTRACE + HAVE_FUNCTION_GRAPH_TRACER
+------------------------------------------------
+
+The function grapher needs a few tweaks in order to work with dynamic ftrace.
+Basically, you will need to:
+ - update:
+ - ftrace_caller()
+ - ftrace_graph_call()
+ - ftrace_graph_caller()
+ - implement:
+ - ftrace_enable_ftrace_graph_caller()
+ - ftrace_disable_ftrace_graph_caller()
<details to be filled>
+Quick notes:
+ - add a nop stub after the ftrace_call location named ftrace_graph_call;
+ stub needs to be large enough to support a call to ftrace_graph_caller()
+ - update ftrace_graph_caller() to work with being called by the new
+ ftrace_caller() since some semantics may have changed
+ - ftrace_enable_ftrace_graph_caller() will runtime patch the
+ ftrace_graph_call location with a call to ftrace_graph_caller()
+ - ftrace_disable_ftrace_graph_caller() will runtime patch the
+ ftrace_graph_call location with nops
diff --git a/Documentation/trace/kmemtrace.txt b/Documentation/trace/kmemtrace.txt
deleted file mode 100644
index 6308735..0000000
--- a/Documentation/trace/kmemtrace.txt
+++ /dev/null
@@ -1,126 +0,0 @@
- kmemtrace - Kernel Memory Tracer
-
- by Eduard - Gabriel Munteanu
- <eduard.munteanu@linux360.ro>
-
-I. Introduction
-===============
-
-kmemtrace helps kernel developers figure out two things:
-1) how different allocators (SLAB, SLUB etc.) perform
-2) how kernel code allocates memory and how much
-
-To do this, we trace every allocation and export information to the userspace
-through the relay interface. We export things such as the number of requested
-bytes, the number of bytes actually allocated (i.e. including internal
-fragmentation), whether this is a slab allocation or a plain kmalloc() and so
-on.
-
-The actual analysis is performed by a userspace tool (see section III for
-details on where to get it from). It logs the data exported by the kernel,
-processes it and (as of writing this) can provide the following information:
-- the total amount of memory allocated and fragmentation per call-site
-- the amount of memory allocated and fragmentation per allocation
-- total memory allocated and fragmentation in the collected dataset
-- number of cross-CPU allocation and frees (makes sense in NUMA environments)
-
-Moreover, it can potentially find inconsistent and erroneous behavior in
-kernel code, such as using slab free functions on kmalloc'ed memory or
-allocating less memory than requested (but not truly failed allocations).
-
-kmemtrace also makes provisions for tracing on some arch and analysing the
-data on another.
-
-II. Design and goals
-====================
-
-kmemtrace was designed to handle rather large amounts of data. Thus, it uses
-the relay interface to export whatever is logged to userspace, which then
-stores it. Analysis and reporting is done asynchronously, that is, after the
-data is collected and stored. By design, it allows one to log and analyse
-on different machines and different arches.
-
-As of writing this, the ABI is not considered stable, though it might not
-change much. However, no guarantees are made about compatibility yet. When
-deemed stable, the ABI should still allow easy extension while maintaining
-backward compatibility. This is described further in Documentation/ABI.
-
-Summary of design goals:
- - allow logging and analysis to be done across different machines
- - be fast and anticipate usage in high-load environments (*)
- - be reasonably extensible
- - make it possible for GNU/Linux distributions to have kmemtrace
- included in their repositories
-
-(*) - one of the reasons Pekka Enberg's original userspace data analysis
- tool's code was rewritten from Perl to C (although this is more than a
- simple conversion)
-
-
-III. Quick usage guide
-======================
-
-1) Get a kernel that supports kmemtrace and build it accordingly (i.e. enable
-CONFIG_KMEMTRACE).
-
-2) Get the userspace tool and build it:
-$ git clone git://repo.or.cz/kmemtrace-user.git # current repository
-$ cd kmemtrace-user/
-$ ./autogen.sh
-$ ./configure
-$ make
-
-3) Boot the kmemtrace-enabled kernel if you haven't, preferably in the
-'single' runlevel (so that relay buffers don't fill up easily), and run
-kmemtrace:
-# '$' does not mean user, but root here.
-$ mount -t debugfs none /sys/kernel/debug
-$ mount -t proc none /proc
-$ cd path/to/kmemtrace-user/
-$ ./kmemtraced
-Wait a bit, then stop it with CTRL+C.
-$ cat /sys/kernel/debug/kmemtrace/total_overruns # Check if we didn't
- # overrun, should
- # be zero.
-$ (Optionally) [Run kmemtrace_check separately on each cpu[0-9]*.out file to
- check its correctness]
-$ ./kmemtrace-report
-
-Now you should have a nice and short summary of how the allocator performs.
-
-IV. FAQ and known issues
-========================
-
-Q: 'cat /sys/kernel/debug/kmemtrace/total_overruns' is non-zero, how do I fix
-this? Should I worry?
-A: If it's non-zero, this affects kmemtrace's accuracy, depending on how
-large the number is. You can fix it by supplying a higher
-'kmemtrace.subbufs=N' kernel parameter.
----
-
-Q: kmemtrace_check reports errors, how do I fix this? Should I worry?
-A: This is a bug and should be reported. It can occur for a variety of
-reasons:
- - possible bugs in relay code
- - possible misuse of relay by kmemtrace
- - timestamps being collected unorderly
-Or you may fix it yourself and send us a patch.
----
-
-Q: kmemtrace_report shows many errors, how do I fix this? Should I worry?
-A: This is a known issue and I'm working on it. These might be true errors
-in kernel code, which may have inconsistent behavior (e.g. allocating memory
-with kmem_cache_alloc() and freeing it with kfree()). Pekka Enberg pointed
-out this behavior may work with SLAB, but may fail with other allocators.
-
-It may also be due to lack of tracing in some unusual allocator functions.
-
-We don't want bug reports regarding this issue yet.
----
-
-V. See also
-===========
-
-Documentation/kernel-parameters.txt
-Documentation/ABI/testing/debugfs-kmemtrace
-
diff --git a/Documentation/trace/kprobetrace.txt b/Documentation/trace/kprobetrace.txt
index ec94748..5f77d94 100644
--- a/Documentation/trace/kprobetrace.txt
+++ b/Documentation/trace/kprobetrace.txt
@@ -42,7 +42,7 @@ Synopsis of kprobe_events
+|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**)
NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types
- (u8/u16/u32/u64/s8/s16/s32/s64) are supported.
+ (u8/u16/u32/u64/s8/s16/s32/s64) and string are supported.
(*) only for return probe.
(**) this is useful for fetching a field of data structures.
diff --git a/Documentation/vm/page-types.c b/Documentation/vm/page-types.c
index 66e9358..ccd951f 100644
--- a/Documentation/vm/page-types.c
+++ b/Documentation/vm/page-types.c
@@ -694,7 +694,7 @@ static void usage(void)
#endif
" -l|--list Show page details in ranges\n"
" -L|--list-each Show page details one by one\n"
-" -N|--no-summary Don't show summay info\n"
+" -N|--no-summary Don't show summary info\n"
" -X|--hwpoison hwpoison pages\n"
" -x|--unpoison unpoison pages\n"
" -h|--help Show this usage message\n"
diff --git a/Documentation/x86/zero-page.txt b/Documentation/x86/zero-page.txt
index feb37e1..cf5437d 100644
--- a/Documentation/x86/zero-page.txt
+++ b/Documentation/x86/zero-page.txt
@@ -18,6 +18,7 @@ Offset Proto Name Meaning
080/010 ALL hd0_info hd0 disk parameter, OBSOLETE!!
090/010 ALL hd1_info hd1 disk parameter, OBSOLETE!!
0A0/010 ALL sys_desc_table System description table (struct sys_desc_table)
+0B0/010 ALL olpc_ofw_header OLPC's OpenFirmware CIF and friends
140/080 ALL edid_info Video mode setup (struct edid_info)
1C0/020 ALL efi_info EFI 32 information (struct efi_info)
1E0/004 ALL alk_mem_k Alternative mem check, in KB
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