2008-01-14 11:51:16 +08:00
|
|
|
config ARCH
|
|
|
|
|
string
|
|
|
|
|
option env="ARCH"
|
|
|
|
|
|
|
|
|
|
config KERNELVERSION
|
|
|
|
|
string
|
|
|
|
|
option env="KERNELVERSION"
|
|
|
|
|
|
2006-06-09 13:12:45 +08:00
|
|
|
config DEFCONFIG_LIST
|
|
|
|
|
string
|
[PATCH] uml: use DEFCONFIG_LIST to avoid reading host's config
This should make sure that, for UML, host's configuration files are not
considered, which avoids various pains to the user. Our dependency are such
that the obtained Kconfig will be valid and will lead to successful
compilation - however they cannot prevent an user from disabling any boot
device, and if an option is not set in the read .config (say
/boot/config-XXX), with make menuconfig ARCH=um, it is not set. This always
disables UBD and all console I/O channels, which leads to non-working UML
kernels, so this bothers users - especially now, since it will happen on
almost every machine (/boot/config-`uname -r` exists almost on every machine).
It can be workarounded with make defconfig ARCH=um, but it is non-obvious and
can be avoided, so please _do_ merge this patch.
Given the existence of options, it could be interesting to implement
(additionally) "option required" - with it, Kconfig will refuse reading a
.config file (from wherever it comes) if the given option is not set. With
this, one could mark with it the option characteristic of the given
architecture (it was an old proposal of Roman Zippel, when I pointed out our
problem):
config UML
option required
default y
However this should be further discussed:
*) for x86, it must support constructs like:
==arch/i386/Kconfig==
config 64BIT
option required
default n
where Kconfig must require that CONFIG_64BIT is disabled or not present in the
read .config.
*) do we want to do such checks only for the starting defconfig or also for
.config? Which leads to:
*) I may want to port a x86_64 .config to x86 and viceversa, or even among more
different archs. Should that be allowed, and in which measure (the user may
force skipping the check for a .config or it is only given a warning by
default)?
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: <kbuild-devel@lists.sourceforge.net>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-20 14:28:23 +08:00
|
|
|
depends on !UML
|
2006-06-09 13:12:45 +08:00
|
|
|
option defconfig_list
|
|
|
|
|
default "/lib/modules/$UNAME_RELEASE/.config"
|
|
|
|
|
default "/etc/kernel-config"
|
|
|
|
|
default "/boot/config-$UNAME_RELEASE"
|
2008-05-26 05:03:18 +08:00
|
|
|
default "$ARCH_DEFCONFIG"
|
2006-06-09 13:12:45 +08:00
|
|
|
default "arch/$ARCH/defconfig"
|
|
|
|
|
|
2009-06-18 07:28:03 +08:00
|
|
|
config CONSTRUCTORS
|
|
|
|
|
bool
|
|
|
|
|
depends on !UML
|
|
|
|
|
|
2010-10-14 14:01:34 +08:00
|
|
|
config HAVE_IRQ_WORK
|
|
|
|
|
bool
|
|
|
|
|
|
|
|
|
|
config IRQ_WORK
|
|
|
|
|
bool
|
|
|
|
|
depends on HAVE_IRQ_WORK
|
|
|
|
|
|
2012-04-20 05:59:57 +08:00
|
|
|
config BUILDTIME_EXTABLE_SORT
|
|
|
|
|
bool
|
|
|
|
|
|
2007-07-31 15:39:23 +08:00
|
|
|
menu "General setup"
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
|
config EXPERIMENTAL
|
|
|
|
|
bool "Prompt for development and/or incomplete code/drivers"
|
|
|
|
|
---help---
|
|
|
|
|
Some of the various things that Linux supports (such as network
|
|
|
|
|
drivers, file systems, network protocols, etc.) can be in a state
|
|
|
|
|
of development where the functionality, stability, or the level of
|
|
|
|
|
testing is not yet high enough for general use. This is usually
|
|
|
|
|
known as the "alpha-test" phase among developers. If a feature is
|
|
|
|
|
currently in alpha-test, then the developers usually discourage
|
|
|
|
|
uninformed widespread use of this feature by the general public to
|
|
|
|
|
avoid "Why doesn't this work?" type mail messages. However, active
|
|
|
|
|
testing and use of these systems is welcomed. Just be aware that it
|
|
|
|
|
may not meet the normal level of reliability or it may fail to work
|
|
|
|
|
in some special cases. Detailed bug reports from people familiar
|
|
|
|
|
with the kernel internals are usually welcomed by the developers
|
|
|
|
|
(before submitting bug reports, please read the documents
|
|
|
|
|
<file:README>, <file:MAINTAINERS>, <file:REPORTING-BUGS>,
|
|
|
|
|
<file:Documentation/BUG-HUNTING>, and
|
|
|
|
|
<file:Documentation/oops-tracing.txt> in the kernel source).
|
|
|
|
|
|
|
|
|
|
This option will also make obsoleted drivers available. These are
|
|
|
|
|
drivers that have been replaced by something else, and/or are
|
|
|
|
|
scheduled to be removed in a future kernel release.
|
|
|
|
|
|
|
|
|
|
Unless you intend to help test and develop a feature or driver that
|
|
|
|
|
falls into this category, or you have a situation that requires
|
|
|
|
|
using these features, you should probably say N here, which will
|
|
|
|
|
cause the configurator to present you with fewer choices. If
|
|
|
|
|
you say Y here, you will be offered the choice of using features or
|
|
|
|
|
drivers that are currently considered to be in the alpha-test phase.
|
|
|
|
|
|
|
|
|
|
config BROKEN
|
|
|
|
|
bool
|
|
|
|
|
|
|
|
|
|
config BROKEN_ON_SMP
|
|
|
|
|
bool
|
|
|
|
|
depends on BROKEN || !SMP
|
|
|
|
|
default y
|
|
|
|
|
|
|
|
|
|
config INIT_ENV_ARG_LIMIT
|
|
|
|
|
int
|
2006-06-30 16:55:51 +08:00
|
|
|
default 32 if !UML
|
|
|
|
|
default 128 if UML
|
2005-04-17 06:20:36 +08:00
|
|
|
help
|
2005-10-31 07:01:46 +08:00
|
|
|
Maximum of each of the number of arguments and environment
|
|
|
|
|
variables passed to init from the kernel command line.
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
|
|
2009-12-22 08:24:06 +08:00
|
|
|
config CROSS_COMPILE
|
|
|
|
|
string "Cross-compiler tool prefix"
|
|
|
|
|
help
|
|
|
|
|
Same as running 'make CROSS_COMPILE=prefix-' but stored for
|
|
|
|
|
default make runs in this kernel build directory. You don't
|
|
|
|
|
need to set this unless you want the configured kernel build
|
|
|
|
|
directory to select the cross-compiler automatically.
|
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
config LOCALVERSION
|
|
|
|
|
string "Local version - append to kernel release"
|
|
|
|
|
help
|
|
|
|
|
Append an extra string to the end of your kernel version.
|
|
|
|
|
This will show up when you type uname, for example.
|
|
|
|
|
The string you set here will be appended after the contents of
|
|
|
|
|
any files with a filename matching localversion* in your
|
|
|
|
|
object and source tree, in that order. Your total string can
|
|
|
|
|
be a maximum of 64 characters.
|
|
|
|
|
|
2005-07-31 16:57:49 +08:00
|
|
|
config LOCALVERSION_AUTO
|
|
|
|
|
bool "Automatically append version information to the version string"
|
|
|
|
|
default y
|
|
|
|
|
help
|
|
|
|
|
This will try to automatically determine if the current tree is a
|
2007-05-02 05:08:11 +08:00
|
|
|
release tree by looking for git tags that belong to the current
|
|
|
|
|
top of tree revision.
|
2005-07-31 16:57:49 +08:00
|
|
|
|
|
|
|
|
A string of the format -gxxxxxxxx will be added to the localversion
|
2007-05-02 05:08:11 +08:00
|
|
|
if a git-based tree is found. The string generated by this will be
|
2005-07-31 16:57:49 +08:00
|
|
|
appended after any matching localversion* files, and after the value
|
2007-05-02 05:08:11 +08:00
|
|
|
set in CONFIG_LOCALVERSION.
|
2005-07-31 16:57:49 +08:00
|
|
|
|
2007-05-02 05:08:11 +08:00
|
|
|
(The actual string used here is the first eight characters produced
|
|
|
|
|
by running the command:
|
|
|
|
|
|
|
|
|
|
$ git rev-parse --verify HEAD
|
|
|
|
|
|
|
|
|
|
which is done within the script "scripts/setlocalversion".)
|
2005-07-31 16:57:49 +08:00
|
|
|
|
2009-01-05 07:41:25 +08:00
|
|
|
config HAVE_KERNEL_GZIP
|
|
|
|
|
bool
|
|
|
|
|
|
|
|
|
|
config HAVE_KERNEL_BZIP2
|
|
|
|
|
bool
|
|
|
|
|
|
|
|
|
|
config HAVE_KERNEL_LZMA
|
|
|
|
|
bool
|
|
|
|
|
|
decompressors: add boot-time XZ support
This implements the API defined in <linux/decompress/generic.h> which is
used for kernel, initramfs, and initrd decompression. This patch together
with the first patch is enough for XZ-compressed initramfs and initrd;
XZ-compressed kernel will need arch-specific changes.
The buffering requirements described in decompress_unxz.c are stricter
than with gzip, so the relevant changes should be done to the
arch-specific code when adding support for XZ-compressed kernel.
Similarly, the heap size in arch-specific pre-boot code may need to be
increased (30 KiB is enough).
The XZ decompressor needs memmove(), memeq() (memcmp() == 0), and
memzero() (memset(ptr, 0, size)), which aren't available in all
arch-specific pre-boot environments. I'm including simple versions in
decompress_unxz.c, but a cleaner solution would naturally be nicer.
Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alain Knaff <alain@knaff.lu>
Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Cc: Phillip Lougher <phillip@lougher.demon.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 09:01:23 +08:00
|
|
|
config HAVE_KERNEL_XZ
|
|
|
|
|
bool
|
|
|
|
|
|
lib: add support for LZO-compressed kernels
This patch series adds generic support for creating and extracting
LZO-compressed kernel images, as well as support for using such images on
the x86 and ARM architectures, and support for creating and using
LZO-compressed initrd and initramfs images.
Russell King said:
: Testing on a Cortex A9 model:
: - lzo decompressor is 65% of the time gzip takes to decompress a kernel
: - lzo kernel is 9% larger than a gzip kernel
:
: which I'm happy to say confirms your figures when comparing the two.
:
: However, when comparing your new gzip code to the old gzip code:
: - new is 99% of the size of the old code
: - new takes 42% of the time to decompress than the old code
:
: What this means is that for a proper comparison, the results get even better:
: - lzo is 7.5% larger than the old gzip'd kernel image
: - lzo takes 28% of the time that the old gzip code took
:
: So the expense seems definitely worth the effort. The only reason I
: can think of ever using gzip would be if you needed the additional
: compression (eg, because you have limited flash to store the image.)
:
: I would argue that the default for ARM should therefore be LZO.
This patch:
The lzo compressor is worse than gzip at compression, but faster at
extraction. Here are some figures for an ARM board I'm working on:
Uncompressed size: 3.24Mo
gzip 1.61Mo 0.72s
lzo 1.75Mo 0.48s
So for a compression ratio that is still relatively close to gzip, it's
much faster to extract, at least in that case.
This part contains:
- Makefile routine to support lzo compression
- Fixes to the existing lzo compressor so that it can be used in
compressed kernels
- wrapper around the existing lzo1x_decompress, as it only extracts one
block at a time, while we need to extract a whole file here
- config dialog for kernel compression
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: cleanup]
Signed-off-by: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Tested-by: Wu Zhangjin <wuzhangjin@gmail.com>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Russell King <rmk@arm.linux.org.uk>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-09 06:42:42 +08:00
|
|
|
config HAVE_KERNEL_LZO
|
|
|
|
|
bool
|
|
|
|
|
|
2009-01-05 05:46:17 +08:00
|
|
|
choice
|
2009-01-05 07:41:25 +08:00
|
|
|
prompt "Kernel compression mode"
|
|
|
|
|
default KERNEL_GZIP
|
decompressors: add boot-time XZ support
This implements the API defined in <linux/decompress/generic.h> which is
used for kernel, initramfs, and initrd decompression. This patch together
with the first patch is enough for XZ-compressed initramfs and initrd;
XZ-compressed kernel will need arch-specific changes.
The buffering requirements described in decompress_unxz.c are stricter
than with gzip, so the relevant changes should be done to the
arch-specific code when adding support for XZ-compressed kernel.
Similarly, the heap size in arch-specific pre-boot code may need to be
increased (30 KiB is enough).
The XZ decompressor needs memmove(), memeq() (memcmp() == 0), and
memzero() (memset(ptr, 0, size)), which aren't available in all
arch-specific pre-boot environments. I'm including simple versions in
decompress_unxz.c, but a cleaner solution would naturally be nicer.
Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alain Knaff <alain@knaff.lu>
Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Cc: Phillip Lougher <phillip@lougher.demon.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 09:01:23 +08:00
|
|
|
depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO
|
2009-01-05 07:41:25 +08:00
|
|
|
help
|
2009-01-05 05:46:17 +08:00
|
|
|
The linux kernel is a kind of self-extracting executable.
|
|
|
|
|
Several compression algorithms are available, which differ
|
|
|
|
|
in efficiency, compression and decompression speed.
|
|
|
|
|
Compression speed is only relevant when building a kernel.
|
|
|
|
|
Decompression speed is relevant at each boot.
|
|
|
|
|
|
|
|
|
|
If you have any problems with bzip2 or lzma compressed
|
|
|
|
|
kernels, mail me (Alain Knaff) <alain@knaff.lu>. (An older
|
|
|
|
|
version of this functionality (bzip2 only), for 2.4, was
|
|
|
|
|
supplied by Christian Ludwig)
|
|
|
|
|
|
|
|
|
|
High compression options are mostly useful for users, who
|
|
|
|
|
are low on disk space (embedded systems), but for whom ram
|
|
|
|
|
size matters less.
|
|
|
|
|
|
|
|
|
|
If in doubt, select 'gzip'
|
|
|
|
|
|
|
|
|
|
config KERNEL_GZIP
|
2009-01-05 07:41:25 +08:00
|
|
|
bool "Gzip"
|
|
|
|
|
depends on HAVE_KERNEL_GZIP
|
|
|
|
|
help
|
lib: add support for LZO-compressed kernels
This patch series adds generic support for creating and extracting
LZO-compressed kernel images, as well as support for using such images on
the x86 and ARM architectures, and support for creating and using
LZO-compressed initrd and initramfs images.
Russell King said:
: Testing on a Cortex A9 model:
: - lzo decompressor is 65% of the time gzip takes to decompress a kernel
: - lzo kernel is 9% larger than a gzip kernel
:
: which I'm happy to say confirms your figures when comparing the two.
:
: However, when comparing your new gzip code to the old gzip code:
: - new is 99% of the size of the old code
: - new takes 42% of the time to decompress than the old code
:
: What this means is that for a proper comparison, the results get even better:
: - lzo is 7.5% larger than the old gzip'd kernel image
: - lzo takes 28% of the time that the old gzip code took
:
: So the expense seems definitely worth the effort. The only reason I
: can think of ever using gzip would be if you needed the additional
: compression (eg, because you have limited flash to store the image.)
:
: I would argue that the default for ARM should therefore be LZO.
This patch:
The lzo compressor is worse than gzip at compression, but faster at
extraction. Here are some figures for an ARM board I'm working on:
Uncompressed size: 3.24Mo
gzip 1.61Mo 0.72s
lzo 1.75Mo 0.48s
So for a compression ratio that is still relatively close to gzip, it's
much faster to extract, at least in that case.
This part contains:
- Makefile routine to support lzo compression
- Fixes to the existing lzo compressor so that it can be used in
compressed kernels
- wrapper around the existing lzo1x_decompress, as it only extracts one
block at a time, while we need to extract a whole file here
- config dialog for kernel compression
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: cleanup]
Signed-off-by: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Tested-by: Wu Zhangjin <wuzhangjin@gmail.com>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Russell King <rmk@arm.linux.org.uk>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-09 06:42:42 +08:00
|
|
|
The old and tried gzip compression. It provides a good balance
|
|
|
|
|
between compression ratio and decompression speed.
|
2009-01-05 05:46:17 +08:00
|
|
|
|
|
|
|
|
config KERNEL_BZIP2
|
|
|
|
|
bool "Bzip2"
|
2009-01-05 07:41:25 +08:00
|
|
|
depends on HAVE_KERNEL_BZIP2
|
2009-01-05 05:46:17 +08:00
|
|
|
help
|
|
|
|
|
Its compression ratio and speed is intermediate.
|
2012-06-01 07:26:46 +08:00
|
|
|
Decompression speed is slowest among the choices. The kernel
|
2009-01-05 07:41:25 +08:00
|
|
|
size is about 10% smaller with bzip2, in comparison to gzip.
|
|
|
|
|
Bzip2 uses a large amount of memory. For modern kernels you
|
|
|
|
|
will need at least 8MB RAM or more for booting.
|
2009-01-05 05:46:17 +08:00
|
|
|
|
|
|
|
|
config KERNEL_LZMA
|
2009-01-05 07:41:25 +08:00
|
|
|
bool "LZMA"
|
|
|
|
|
depends on HAVE_KERNEL_LZMA
|
|
|
|
|
help
|
2012-06-01 07:26:46 +08:00
|
|
|
This compression algorithm's ratio is best. Decompression speed
|
|
|
|
|
is between gzip and bzip2. Compression is slowest.
|
|
|
|
|
The kernel size is about 33% smaller with LZMA in comparison to gzip.
|
2009-01-05 05:46:17 +08:00
|
|
|
|
decompressors: add boot-time XZ support
This implements the API defined in <linux/decompress/generic.h> which is
used for kernel, initramfs, and initrd decompression. This patch together
with the first patch is enough for XZ-compressed initramfs and initrd;
XZ-compressed kernel will need arch-specific changes.
The buffering requirements described in decompress_unxz.c are stricter
than with gzip, so the relevant changes should be done to the
arch-specific code when adding support for XZ-compressed kernel.
Similarly, the heap size in arch-specific pre-boot code may need to be
increased (30 KiB is enough).
The XZ decompressor needs memmove(), memeq() (memcmp() == 0), and
memzero() (memset(ptr, 0, size)), which aren't available in all
arch-specific pre-boot environments. I'm including simple versions in
decompress_unxz.c, but a cleaner solution would naturally be nicer.
Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alain Knaff <alain@knaff.lu>
Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Cc: Phillip Lougher <phillip@lougher.demon.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 09:01:23 +08:00
|
|
|
config KERNEL_XZ
|
|
|
|
|
bool "XZ"
|
|
|
|
|
depends on HAVE_KERNEL_XZ
|
|
|
|
|
help
|
|
|
|
|
XZ uses the LZMA2 algorithm and instruction set specific
|
|
|
|
|
BCJ filters which can improve compression ratio of executable
|
|
|
|
|
code. The size of the kernel is about 30% smaller with XZ in
|
|
|
|
|
comparison to gzip. On architectures for which there is a BCJ
|
|
|
|
|
filter (i386, x86_64, ARM, IA-64, PowerPC, and SPARC), XZ
|
|
|
|
|
will create a few percent smaller kernel than plain LZMA.
|
|
|
|
|
|
|
|
|
|
The speed is about the same as with LZMA: The decompression
|
|
|
|
|
speed of XZ is better than that of bzip2 but worse than gzip
|
|
|
|
|
and LZO. Compression is slow.
|
|
|
|
|
|
lib: add support for LZO-compressed kernels
This patch series adds generic support for creating and extracting
LZO-compressed kernel images, as well as support for using such images on
the x86 and ARM architectures, and support for creating and using
LZO-compressed initrd and initramfs images.
Russell King said:
: Testing on a Cortex A9 model:
: - lzo decompressor is 65% of the time gzip takes to decompress a kernel
: - lzo kernel is 9% larger than a gzip kernel
:
: which I'm happy to say confirms your figures when comparing the two.
:
: However, when comparing your new gzip code to the old gzip code:
: - new is 99% of the size of the old code
: - new takes 42% of the time to decompress than the old code
:
: What this means is that for a proper comparison, the results get even better:
: - lzo is 7.5% larger than the old gzip'd kernel image
: - lzo takes 28% of the time that the old gzip code took
:
: So the expense seems definitely worth the effort. The only reason I
: can think of ever using gzip would be if you needed the additional
: compression (eg, because you have limited flash to store the image.)
:
: I would argue that the default for ARM should therefore be LZO.
This patch:
The lzo compressor is worse than gzip at compression, but faster at
extraction. Here are some figures for an ARM board I'm working on:
Uncompressed size: 3.24Mo
gzip 1.61Mo 0.72s
lzo 1.75Mo 0.48s
So for a compression ratio that is still relatively close to gzip, it's
much faster to extract, at least in that case.
This part contains:
- Makefile routine to support lzo compression
- Fixes to the existing lzo compressor so that it can be used in
compressed kernels
- wrapper around the existing lzo1x_decompress, as it only extracts one
block at a time, while we need to extract a whole file here
- config dialog for kernel compression
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: cleanup]
Signed-off-by: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Tested-by: Wu Zhangjin <wuzhangjin@gmail.com>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Russell King <rmk@arm.linux.org.uk>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-09 06:42:42 +08:00
|
|
|
config KERNEL_LZO
|
|
|
|
|
bool "LZO"
|
|
|
|
|
depends on HAVE_KERNEL_LZO
|
|
|
|
|
help
|
2012-06-01 07:26:46 +08:00
|
|
|
Its compression ratio is the poorest among the choices. The kernel
|
2010-07-14 17:23:08 +08:00
|
|
|
size is about 10% bigger than gzip; however its speed
|
lib: add support for LZO-compressed kernels
This patch series adds generic support for creating and extracting
LZO-compressed kernel images, as well as support for using such images on
the x86 and ARM architectures, and support for creating and using
LZO-compressed initrd and initramfs images.
Russell King said:
: Testing on a Cortex A9 model:
: - lzo decompressor is 65% of the time gzip takes to decompress a kernel
: - lzo kernel is 9% larger than a gzip kernel
:
: which I'm happy to say confirms your figures when comparing the two.
:
: However, when comparing your new gzip code to the old gzip code:
: - new is 99% of the size of the old code
: - new takes 42% of the time to decompress than the old code
:
: What this means is that for a proper comparison, the results get even better:
: - lzo is 7.5% larger than the old gzip'd kernel image
: - lzo takes 28% of the time that the old gzip code took
:
: So the expense seems definitely worth the effort. The only reason I
: can think of ever using gzip would be if you needed the additional
: compression (eg, because you have limited flash to store the image.)
:
: I would argue that the default for ARM should therefore be LZO.
This patch:
The lzo compressor is worse than gzip at compression, but faster at
extraction. Here are some figures for an ARM board I'm working on:
Uncompressed size: 3.24Mo
gzip 1.61Mo 0.72s
lzo 1.75Mo 0.48s
So for a compression ratio that is still relatively close to gzip, it's
much faster to extract, at least in that case.
This part contains:
- Makefile routine to support lzo compression
- Fixes to the existing lzo compressor so that it can be used in
compressed kernels
- wrapper around the existing lzo1x_decompress, as it only extracts one
block at a time, while we need to extract a whole file here
- config dialog for kernel compression
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: cleanup]
Signed-off-by: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Tested-by: Wu Zhangjin <wuzhangjin@gmail.com>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Russell King <rmk@arm.linux.org.uk>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-09 06:42:42 +08:00
|
|
|
(both compression and decompression) is the fastest.
|
|
|
|
|
|
2009-01-05 05:46:17 +08:00
|
|
|
endchoice
|
|
|
|
|
|
uts: make default hostname configurable, rather than always using "(none)"
The "hostname" tool falls back to setting the hostname to "localhost" if
/etc/hostname does not exist. Distribution init scripts have the same
fallback. However, if userspace never calls sethostname, such as when
booting with init=/bin/sh, or otherwise booting a minimal system without
the usual init scripts, the default hostname of "(none)" remains,
unhelpfully appearing in various places such as prompts ("root@(none):~#")
and logs. Furthermore, "(none)" doesn't typically resolve to anything
useful.
Make the default hostname configurable. This removes the need for the
standard fallback, provides a useful default for systems that never call
sethostname, and makes minimal systems that much more useful with less
configuration. Distributions could choose to use "localhost" here to
avoid the fallback, while embedded systems may wish to use a specific
target hostname.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: David Miller <davem@davemloft.net>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Kel Modderman <kel@otaku42.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-16 06:08:28 +08:00
|
|
|
config DEFAULT_HOSTNAME
|
|
|
|
|
string "Default hostname"
|
|
|
|
|
default "(none)"
|
|
|
|
|
help
|
|
|
|
|
This option determines the default system hostname before userspace
|
|
|
|
|
calls sethostname(2). The kernel traditionally uses "(none)" here,
|
|
|
|
|
but you may wish to use a different default here to make a minimal
|
|
|
|
|
system more usable with less configuration.
|
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
config SWAP
|
|
|
|
|
bool "Support for paging of anonymous memory (swap)"
|
[PATCH] BLOCK: Make it possible to disable the block layer [try #6]
Make it possible to disable the block layer. Not all embedded devices require
it, some can make do with just JFFS2, NFS, ramfs, etc - none of which require
the block layer to be present.
This patch does the following:
(*) Introduces CONFIG_BLOCK to disable the block layer, buffering and blockdev
support.
(*) Adds dependencies on CONFIG_BLOCK to any configuration item that controls
an item that uses the block layer. This includes:
(*) Block I/O tracing.
(*) Disk partition code.
(*) All filesystems that are block based, eg: Ext3, ReiserFS, ISOFS.
(*) The SCSI layer. As far as I can tell, even SCSI chardevs use the
block layer to do scheduling. Some drivers that use SCSI facilities -
such as USB storage - end up disabled indirectly from this.
(*) Various block-based device drivers, such as IDE and the old CDROM
drivers.
(*) MTD blockdev handling and FTL.
(*) JFFS - which uses set_bdev_super(), something it could avoid doing by
taking a leaf out of JFFS2's book.
(*) Makes most of the contents of linux/blkdev.h, linux/buffer_head.h and
linux/elevator.h contingent on CONFIG_BLOCK being set. sector_div() is,
however, still used in places, and so is still available.
(*) Also made contingent are the contents of linux/mpage.h, linux/genhd.h and
parts of linux/fs.h.
(*) Makes a number of files in fs/ contingent on CONFIG_BLOCK.
(*) Makes mm/bounce.c (bounce buffering) contingent on CONFIG_BLOCK.
(*) set_page_dirty() doesn't call __set_page_dirty_buffers() if CONFIG_BLOCK
is not enabled.
(*) fs/no-block.c is created to hold out-of-line stubs and things that are
required when CONFIG_BLOCK is not set:
(*) Default blockdev file operations (to give error ENODEV on opening).
(*) Makes some /proc changes:
(*) /proc/devices does not list any blockdevs.
(*) /proc/diskstats and /proc/partitions are contingent on CONFIG_BLOCK.
(*) Makes some compat ioctl handling contingent on CONFIG_BLOCK.
(*) If CONFIG_BLOCK is not defined, makes sys_quotactl() return -ENODEV if
given command other than Q_SYNC or if a special device is specified.
(*) In init/do_mounts.c, no reference is made to the blockdev routines if
CONFIG_BLOCK is not defined. This does not prohibit NFS roots or JFFS2.
(*) The bdflush, ioprio_set and ioprio_get syscalls can now be absent (return
error ENOSYS by way of cond_syscall if so).
(*) The seclvl_bd_claim() and seclvl_bd_release() security calls do nothing if
CONFIG_BLOCK is not set, since they can't then happen.
Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2006-10-01 02:45:40 +08:00
|
|
|
depends on MMU && BLOCK
|
2005-04-17 06:20:36 +08:00
|
|
|
default y
|
|
|
|
|
help
|
|
|
|
|
This option allows you to choose whether you want to have support
|
2006-01-15 09:40:08 +08:00
|
|
|
for so called swap devices or swap files in your kernel that are
|
2005-04-17 06:20:36 +08:00
|
|
|
used to provide more virtual memory than the actual RAM present
|
|
|
|
|
in your computer. If unsure say Y.
|
|
|
|
|
|
|
|
|
|
config SYSVIPC
|
|
|
|
|
bool "System V IPC"
|
|
|
|
|
---help---
|
|
|
|
|
Inter Process Communication is a suite of library functions and
|
|
|
|
|
system calls which let processes (running programs) synchronize and
|
|
|
|
|
exchange information. It is generally considered to be a good thing,
|
|
|
|
|
and some programs won't run unless you say Y here. In particular, if
|
|
|
|
|
you want to run the DOS emulator dosemu under Linux (read the
|
|
|
|
|
DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
|
|
|
|
|
you'll need to say Y here.
|
|
|
|
|
|
|
|
|
|
You can find documentation about IPC with "info ipc" and also in
|
|
|
|
|
section 6.4 of the Linux Programmer's Guide, available from
|
|
|
|
|
<http://www.tldp.org/guides.html>.
|
|
|
|
|
|
2007-02-14 16:34:06 +08:00
|
|
|
config SYSVIPC_SYSCTL
|
|
|
|
|
bool
|
|
|
|
|
depends on SYSVIPC
|
|
|
|
|
depends on SYSCTL
|
|
|
|
|
default y
|
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
config POSIX_MQUEUE
|
|
|
|
|
bool "POSIX Message Queues"
|
|
|
|
|
depends on NET && EXPERIMENTAL
|
|
|
|
|
---help---
|
|
|
|
|
POSIX variant of message queues is a part of IPC. In POSIX message
|
|
|
|
|
queues every message has a priority which decides about succession
|
|
|
|
|
of receiving it by a process. If you want to compile and run
|
|
|
|
|
programs written e.g. for Solaris with use of its POSIX message
|
2007-05-09 13:25:13 +08:00
|
|
|
queues (functions mq_*) say Y here.
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
|
POSIX message queues are visible as a filesystem called 'mqueue'
|
|
|
|
|
and can be mounted somewhere if you want to do filesystem
|
|
|
|
|
operations on message queues.
|
|
|
|
|
|
|
|
|
|
If unsure, say Y.
|
|
|
|
|
|
2009-04-07 10:01:11 +08:00
|
|
|
config POSIX_MQUEUE_SYSCTL
|
|
|
|
|
bool
|
|
|
|
|
depends on POSIX_MQUEUE
|
|
|
|
|
depends on SYSCTL
|
|
|
|
|
default y
|
|
|
|
|
|
2012-09-09 20:22:07 +08:00
|
|
|
config FHANDLE
|
|
|
|
|
bool "open by fhandle syscalls"
|
|
|
|
|
select EXPORTFS
|
|
|
|
|
help
|
|
|
|
|
If you say Y here, a user level program will be able to map
|
|
|
|
|
file names to handle and then later use the handle for
|
|
|
|
|
different file system operations. This is useful in implementing
|
|
|
|
|
userspace file servers, which now track files using handles instead
|
|
|
|
|
of names. The handle would remain the same even if file names
|
|
|
|
|
get renamed. Enables open_by_handle_at(2) and name_to_handle_at(2)
|
|
|
|
|
syscalls.
|
|
|
|
|
|
|
|
|
|
config AUDIT
|
|
|
|
|
bool "Auditing support"
|
|
|
|
|
depends on NET
|
|
|
|
|
help
|
|
|
|
|
Enable auditing infrastructure that can be used with another
|
|
|
|
|
kernel subsystem, such as SELinux (which requires this for
|
|
|
|
|
logging of avc messages output). Does not do system-call
|
|
|
|
|
auditing without CONFIG_AUDITSYSCALL.
|
|
|
|
|
|
|
|
|
|
config AUDITSYSCALL
|
|
|
|
|
bool "Enable system-call auditing support"
|
|
|
|
|
depends on AUDIT && (X86 || PPC || S390 || IA64 || UML || SPARC64 || SUPERH || (ARM && AEABI && !OABI_COMPAT))
|
|
|
|
|
default y if SECURITY_SELINUX
|
|
|
|
|
help
|
|
|
|
|
Enable low-overhead system-call auditing infrastructure that
|
|
|
|
|
can be used independently or with another kernel subsystem,
|
|
|
|
|
such as SELinux.
|
|
|
|
|
|
|
|
|
|
config AUDIT_WATCH
|
|
|
|
|
def_bool y
|
|
|
|
|
depends on AUDITSYSCALL
|
|
|
|
|
select FSNOTIFY
|
|
|
|
|
|
|
|
|
|
config AUDIT_TREE
|
|
|
|
|
def_bool y
|
|
|
|
|
depends on AUDITSYSCALL
|
|
|
|
|
select FSNOTIFY
|
|
|
|
|
|
|
|
|
|
config AUDIT_LOGINUID_IMMUTABLE
|
|
|
|
|
bool "Make audit loginuid immutable"
|
|
|
|
|
depends on AUDIT
|
|
|
|
|
help
|
|
|
|
|
The config option toggles if a task setting its loginuid requires
|
|
|
|
|
CAP_SYS_AUDITCONTROL or if that task should require no special permissions
|
|
|
|
|
but should instead only allow setting its loginuid if it was never
|
|
|
|
|
previously set. On systems which use systemd or a similar central
|
|
|
|
|
process to restart login services this should be set to true. On older
|
|
|
|
|
systems in which an admin would typically have to directly stop and
|
|
|
|
|
start processes this should be set to false. Setting this to true allows
|
|
|
|
|
one to drop potentially dangerous capabilites from the login tasks,
|
|
|
|
|
but may not be backwards compatible with older init systems.
|
|
|
|
|
|
|
|
|
|
source "kernel/irq/Kconfig"
|
|
|
|
|
source "kernel/time/Kconfig"
|
|
|
|
|
|
|
|
|
|
menu "CPU/Task time and stats accounting"
|
|
|
|
|
|
2012-09-09 20:56:31 +08:00
|
|
|
choice
|
|
|
|
|
prompt "Cputime accounting"
|
|
|
|
|
default TICK_CPU_ACCOUNTING if !PPC64
|
|
|
|
|
default VIRT_CPU_ACCOUNTING if PPC64
|
|
|
|
|
|
|
|
|
|
# Kind of a stub config for the pure tick based cputime accounting
|
|
|
|
|
config TICK_CPU_ACCOUNTING
|
|
|
|
|
bool "Simple tick based cputime accounting"
|
|
|
|
|
depends on !S390
|
|
|
|
|
help
|
|
|
|
|
This is the basic tick based cputime accounting that maintains
|
|
|
|
|
statistics about user, system and idle time spent on per jiffies
|
|
|
|
|
granularity.
|
|
|
|
|
|
|
|
|
|
If unsure, say Y.
|
|
|
|
|
|
2012-06-16 21:39:34 +08:00
|
|
|
config VIRT_CPU_ACCOUNTING
|
|
|
|
|
bool "Deterministic task and CPU time accounting"
|
|
|
|
|
depends on HAVE_VIRT_CPU_ACCOUNTING
|
|
|
|
|
help
|
|
|
|
|
Select this option to enable more accurate task and CPU time
|
|
|
|
|
accounting. This is done by reading a CPU counter on each
|
|
|
|
|
kernel entry and exit and on transitions within the kernel
|
|
|
|
|
between system, softirq and hardirq state, so there is a
|
|
|
|
|
small performance impact. In the case of s390 or IBM POWER > 5,
|
|
|
|
|
this also enables accounting of stolen time on logically-partitioned
|
|
|
|
|
systems.
|
|
|
|
|
|
2012-09-09 20:56:31 +08:00
|
|
|
config IRQ_TIME_ACCOUNTING
|
|
|
|
|
bool "Fine granularity task level IRQ time accounting"
|
|
|
|
|
depends on HAVE_IRQ_TIME_ACCOUNTING
|
|
|
|
|
help
|
|
|
|
|
Select this option to enable fine granularity task irq time
|
|
|
|
|
accounting. This is done by reading a timestamp on each
|
|
|
|
|
transitions between softirq and hardirq state, so there can be a
|
|
|
|
|
small performance impact.
|
|
|
|
|
|
|
|
|
|
If in doubt, say N here.
|
|
|
|
|
|
|
|
|
|
endchoice
|
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
config BSD_PROCESS_ACCT
|
|
|
|
|
bool "BSD Process Accounting"
|
|
|
|
|
help
|
|
|
|
|
If you say Y here, a user level program will be able to instruct the
|
|
|
|
|
kernel (via a special system call) to write process accounting
|
|
|
|
|
information to a file: whenever a process exits, information about
|
|
|
|
|
that process will be appended to the file by the kernel. The
|
|
|
|
|
information includes things such as creation time, owning user,
|
|
|
|
|
command name, memory usage, controlling terminal etc. (the complete
|
|
|
|
|
list is in the struct acct in <file:include/linux/acct.h>). It is
|
|
|
|
|
up to the user level program to do useful things with this
|
|
|
|
|
information. This is generally a good idea, so say Y.
|
|
|
|
|
|
|
|
|
|
config BSD_PROCESS_ACCT_V3
|
|
|
|
|
bool "BSD Process Accounting version 3 file format"
|
|
|
|
|
depends on BSD_PROCESS_ACCT
|
|
|
|
|
default n
|
|
|
|
|
help
|
|
|
|
|
If you say Y here, the process accounting information is written
|
|
|
|
|
in a new file format that also logs the process IDs of each
|
|
|
|
|
process and it's parent. Note that this file format is incompatible
|
|
|
|
|
with previous v0/v1/v2 file formats, so you will need updated tools
|
|
|
|
|
for processing it. A preliminary version of these tools is available
|
2008-06-18 16:45:13 +08:00
|
|
|
at <http://www.gnu.org/software/acct/>.
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2006-07-14 15:24:40 +08:00
|
|
|
config TASKSTATS
|
|
|
|
|
bool "Export task/process statistics through netlink (EXPERIMENTAL)"
|
|
|
|
|
depends on NET
|
|
|
|
|
default n
|
|
|
|
|
help
|
|
|
|
|
Export selected statistics for tasks/processes through the
|
|
|
|
|
generic netlink interface. Unlike BSD process accounting, the
|
|
|
|
|
statistics are available during the lifetime of tasks/processes as
|
|
|
|
|
responses to commands. Like BSD accounting, they are sent to user
|
|
|
|
|
space on task exit.
|
|
|
|
|
|
|
|
|
|
Say N if unsure.
|
|
|
|
|
|
2006-07-14 15:24:36 +08:00
|
|
|
config TASK_DELAY_ACCT
|
|
|
|
|
bool "Enable per-task delay accounting (EXPERIMENTAL)"
|
2006-07-14 15:24:41 +08:00
|
|
|
depends on TASKSTATS
|
2006-07-14 15:24:36 +08:00
|
|
|
help
|
|
|
|
|
Collect information on time spent by a task waiting for system
|
|
|
|
|
resources like cpu, synchronous block I/O completion and swapping
|
|
|
|
|
in pages. Such statistics can help in setting a task's priorities
|
|
|
|
|
relative to other tasks for cpu, io, rss limits etc.
|
|
|
|
|
|
|
|
|
|
Say N if unsure.
|
|
|
|
|
|
2007-02-10 17:46:44 +08:00
|
|
|
config TASK_XACCT
|
|
|
|
|
bool "Enable extended accounting over taskstats (EXPERIMENTAL)"
|
|
|
|
|
depends on TASKSTATS
|
|
|
|
|
help
|
|
|
|
|
Collect extended task accounting data and send the data
|
|
|
|
|
to userland for processing over the taskstats interface.
|
|
|
|
|
|
|
|
|
|
Say N if unsure.
|
|
|
|
|
|
|
|
|
|
config TASK_IO_ACCOUNTING
|
|
|
|
|
bool "Enable per-task storage I/O accounting (EXPERIMENTAL)"
|
|
|
|
|
depends on TASK_XACCT
|
|
|
|
|
help
|
|
|
|
|
Collect information on the number of bytes of storage I/O which this
|
|
|
|
|
task has caused.
|
|
|
|
|
|
|
|
|
|
Say N if unsure.
|
|
|
|
|
|
2012-09-09 20:22:07 +08:00
|
|
|
endmenu # "CPU/Task time and stats accounting"
|
2010-09-27 20:45:59 +08:00
|
|
|
|
2009-01-16 04:28:29 +08:00
|
|
|
menu "RCU Subsystem"
|
|
|
|
|
|
|
|
|
|
choice
|
|
|
|
|
prompt "RCU Implementation"
|
2009-04-03 12:06:25 +08:00
|
|
|
default TREE_RCU
|
2009-01-16 04:28:29 +08:00
|
|
|
|
|
|
|
|
config TREE_RCU
|
|
|
|
|
bool "Tree-based hierarchical RCU"
|
2010-07-21 21:52:40 +08:00
|
|
|
depends on !PREEMPT && SMP
|
2009-01-16 04:28:29 +08:00
|
|
|
help
|
|
|
|
|
This option selects the RCU implementation that is
|
|
|
|
|
designed for very large SMP system with hundreds or
|
2009-06-24 08:12:47 +08:00
|
|
|
thousands of CPUs. It also scales down nicely to
|
|
|
|
|
smaller systems.
|
2009-01-16 04:28:29 +08:00
|
|
|
|
rcu: Merge preemptable-RCU functionality into hierarchical RCU
Create a kernel/rcutree_plugin.h file that contains definitions
for preemptable RCU (or, under the #else branch of the #ifdef,
empty definitions for the classic non-preemptable semantics).
These definitions fit into plugins defined in kernel/rcutree.c
for this purpose.
This variant of preemptable RCU uses a new algorithm whose
read-side expense is roughly that of classic hierarchical RCU
under CONFIG_PREEMPT. This new algorithm's update-side expense
is similar to that of classic hierarchical RCU, and, in absence
of read-side preemption or blocking, is exactly that of classic
hierarchical RCU. Perhaps more important, this new algorithm
has a much simpler implementation, saving well over 1,000 lines
of code compared to mainline's implementation of preemptable
RCU, which will hopefully be retired in favor of this new
algorithm.
The simplifications are obtained by maintaining per-task
nesting state for running tasks, and using a simple
lock-protected algorithm to handle accounting when tasks block
within RCU read-side critical sections, making use of lessons
learned while creating numerous user-level RCU implementations
over the past 18 months.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <12509746134003-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-23 04:56:52 +08:00
|
|
|
config TREE_PREEMPT_RCU
|
2010-06-30 07:49:16 +08:00
|
|
|
bool "Preemptible tree-based hierarchical RCU"
|
2011-06-09 07:31:33 +08:00
|
|
|
depends on PREEMPT && SMP
|
rcu: Merge preemptable-RCU functionality into hierarchical RCU
Create a kernel/rcutree_plugin.h file that contains definitions
for preemptable RCU (or, under the #else branch of the #ifdef,
empty definitions for the classic non-preemptable semantics).
These definitions fit into plugins defined in kernel/rcutree.c
for this purpose.
This variant of preemptable RCU uses a new algorithm whose
read-side expense is roughly that of classic hierarchical RCU
under CONFIG_PREEMPT. This new algorithm's update-side expense
is similar to that of classic hierarchical RCU, and, in absence
of read-side preemption or blocking, is exactly that of classic
hierarchical RCU. Perhaps more important, this new algorithm
has a much simpler implementation, saving well over 1,000 lines
of code compared to mainline's implementation of preemptable
RCU, which will hopefully be retired in favor of this new
algorithm.
The simplifications are obtained by maintaining per-task
nesting state for running tasks, and using a simple
lock-protected algorithm to handle accounting when tasks block
within RCU read-side critical sections, making use of lessons
learned while creating numerous user-level RCU implementations
over the past 18 months.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <12509746134003-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-23 04:56:52 +08:00
|
|
|
help
|
|
|
|
|
This option selects the RCU implementation that is
|
|
|
|
|
designed for very large SMP systems with hundreds or
|
|
|
|
|
thousands of CPUs, but for which real-time response
|
2009-09-14 00:15:08 +08:00
|
|
|
is also required. It also scales down nicely to
|
|
|
|
|
smaller systems.
|
rcu: Merge preemptable-RCU functionality into hierarchical RCU
Create a kernel/rcutree_plugin.h file that contains definitions
for preemptable RCU (or, under the #else branch of the #ifdef,
empty definitions for the classic non-preemptable semantics).
These definitions fit into plugins defined in kernel/rcutree.c
for this purpose.
This variant of preemptable RCU uses a new algorithm whose
read-side expense is roughly that of classic hierarchical RCU
under CONFIG_PREEMPT. This new algorithm's update-side expense
is similar to that of classic hierarchical RCU, and, in absence
of read-side preemption or blocking, is exactly that of classic
hierarchical RCU. Perhaps more important, this new algorithm
has a much simpler implementation, saving well over 1,000 lines
of code compared to mainline's implementation of preemptable
RCU, which will hopefully be retired in favor of this new
algorithm.
The simplifications are obtained by maintaining per-task
nesting state for running tasks, and using a simple
lock-protected algorithm to handle accounting when tasks block
within RCU read-side critical sections, making use of lessons
learned while creating numerous user-level RCU implementations
over the past 18 months.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <12509746134003-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-23 04:56:52 +08:00
|
|
|
|
rcu: "Tiny RCU", The Bloatwatch Edition
This patch is a version of RCU designed for !SMP provided for a
small-footprint RCU implementation. In particular, the
implementation of synchronize_rcu() is extremely lightweight and
high performance. It passes rcutorture testing in each of the
four relevant configurations (combinations of NO_HZ and PREEMPT)
on x86. This saves about 1K bytes compared to old Classic RCU
(which is no longer in mainline), and more than three kilobytes
compared to Hierarchical RCU (updated to 2.6.30):
CONFIG_TREE_RCU:
text data bss dec filename
183 4 0 187 kernel/rcupdate.o
2783 520 36 3339 kernel/rcutree.o
3526 Total (vs 4565 for v7)
CONFIG_TREE_PREEMPT_RCU:
text data bss dec filename
263 4 0 267 kernel/rcupdate.o
4594 776 52 5422 kernel/rcutree.o
5689 Total (6155 for v7)
CONFIG_TINY_RCU:
text data bss dec filename
96 4 0 100 kernel/rcupdate.o
734 24 0 758 kernel/rcutiny.o
858 Total (vs 848 for v7)
The above is for x86. Your mileage may vary on other platforms.
Further compression is possible, but is being procrastinated.
Changes from v7 (http://lkml.org/lkml/2009/10/9/388)
o Apply Lai Jiangshan's review comments (aside from
might_sleep() in synchronize_sched(), which is covered by SMP builds).
o Fix up expedited primitives.
Changes from v6 (http://lkml.org/lkml/2009/9/23/293).
o Forward ported to put it into the 2.6.33 stream.
o Added lockdep support.
o Make lightweight rcu_barrier.
Changes from v5 (http://lkml.org/lkml/2009/6/23/12).
o Ported to latest pre-2.6.32 merge window kernel.
- Renamed rcu_qsctr_inc() to rcu_sched_qs().
- Renamed rcu_bh_qsctr_inc() to rcu_bh_qs().
- Provided trivial rcu_cpu_notify().
- Provided trivial exit_rcu().
- Provided trivial rcu_needs_cpu().
- Fixed up the rcu_*_enter/exit() functions in linux/hardirq.h.
o Removed the dependence on EMBEDDED, with a view to making
TINY_RCU default for !SMP at some time in the future.
o Added (trivial) support for expedited grace periods.
Changes from v4 (http://lkml.org/lkml/2009/5/2/91) include:
o Squeeze the size down a bit further by removing the
->completed field from struct rcu_ctrlblk.
o This permits synchronize_rcu() to become the empty function.
Previous concerns about rcutorture were unfounded, as
rcutorture correctly handles a constant value from
rcu_batches_completed() and rcu_batches_completed_bh().
Changes from v3 (http://lkml.org/lkml/2009/3/29/221) include:
o Changed rcu_batches_completed(), rcu_batches_completed_bh()
rcu_enter_nohz(), rcu_exit_nohz(), rcu_nmi_enter(), and
rcu_nmi_exit(), to be static inlines, as suggested by David
Howells. Doing this saves about 100 bytes from rcutiny.o.
(The numbers between v3 and this v4 of the patch are not directly
comparable, since they are against different versions of Linux.)
Changes from v2 (http://lkml.org/lkml/2009/2/3/333) include:
o Fix whitespace issues.
o Change short-circuit "||" operator to instead be "+" in order
to fix performance bug noted by "kraai" on LWN.
(http://lwn.net/Articles/324348/)
Changes from v1 (http://lkml.org/lkml/2009/1/13/440) include:
o This version depends on EMBEDDED as well as !SMP, as suggested
by Ingo.
o Updated rcu_needs_cpu() to unconditionally return zero,
permitting the CPU to enter dynticks-idle mode at any time.
This works because callbacks can be invoked upon entry to
dynticks-idle mode.
o Paul is now OK with this being included, based on a poll at
the Kernel Miniconf at linux.conf.au, where about ten people said
that they cared about saving 900 bytes on single-CPU systems.
o Applies to both mainline and tip/core/rcu.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Josh Triplett <josh@joshtriplett.org>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: avi@redhat.com
Cc: mtosatti@redhat.com
LKML-Reference: <12565226351355-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-26 10:03:50 +08:00
|
|
|
config TINY_RCU
|
|
|
|
|
bool "UP-only small-memory-footprint RCU"
|
2011-06-09 07:31:33 +08:00
|
|
|
depends on !PREEMPT && !SMP
|
rcu: "Tiny RCU", The Bloatwatch Edition
This patch is a version of RCU designed for !SMP provided for a
small-footprint RCU implementation. In particular, the
implementation of synchronize_rcu() is extremely lightweight and
high performance. It passes rcutorture testing in each of the
four relevant configurations (combinations of NO_HZ and PREEMPT)
on x86. This saves about 1K bytes compared to old Classic RCU
(which is no longer in mainline), and more than three kilobytes
compared to Hierarchical RCU (updated to 2.6.30):
CONFIG_TREE_RCU:
text data bss dec filename
183 4 0 187 kernel/rcupdate.o
2783 520 36 3339 kernel/rcutree.o
3526 Total (vs 4565 for v7)
CONFIG_TREE_PREEMPT_RCU:
text data bss dec filename
263 4 0 267 kernel/rcupdate.o
4594 776 52 5422 kernel/rcutree.o
5689 Total (6155 for v7)
CONFIG_TINY_RCU:
text data bss dec filename
96 4 0 100 kernel/rcupdate.o
734 24 0 758 kernel/rcutiny.o
858 Total (vs 848 for v7)
The above is for x86. Your mileage may vary on other platforms.
Further compression is possible, but is being procrastinated.
Changes from v7 (http://lkml.org/lkml/2009/10/9/388)
o Apply Lai Jiangshan's review comments (aside from
might_sleep() in synchronize_sched(), which is covered by SMP builds).
o Fix up expedited primitives.
Changes from v6 (http://lkml.org/lkml/2009/9/23/293).
o Forward ported to put it into the 2.6.33 stream.
o Added lockdep support.
o Make lightweight rcu_barrier.
Changes from v5 (http://lkml.org/lkml/2009/6/23/12).
o Ported to latest pre-2.6.32 merge window kernel.
- Renamed rcu_qsctr_inc() to rcu_sched_qs().
- Renamed rcu_bh_qsctr_inc() to rcu_bh_qs().
- Provided trivial rcu_cpu_notify().
- Provided trivial exit_rcu().
- Provided trivial rcu_needs_cpu().
- Fixed up the rcu_*_enter/exit() functions in linux/hardirq.h.
o Removed the dependence on EMBEDDED, with a view to making
TINY_RCU default for !SMP at some time in the future.
o Added (trivial) support for expedited grace periods.
Changes from v4 (http://lkml.org/lkml/2009/5/2/91) include:
o Squeeze the size down a bit further by removing the
->completed field from struct rcu_ctrlblk.
o This permits synchronize_rcu() to become the empty function.
Previous concerns about rcutorture were unfounded, as
rcutorture correctly handles a constant value from
rcu_batches_completed() and rcu_batches_completed_bh().
Changes from v3 (http://lkml.org/lkml/2009/3/29/221) include:
o Changed rcu_batches_completed(), rcu_batches_completed_bh()
rcu_enter_nohz(), rcu_exit_nohz(), rcu_nmi_enter(), and
rcu_nmi_exit(), to be static inlines, as suggested by David
Howells. Doing this saves about 100 bytes from rcutiny.o.
(The numbers between v3 and this v4 of the patch are not directly
comparable, since they are against different versions of Linux.)
Changes from v2 (http://lkml.org/lkml/2009/2/3/333) include:
o Fix whitespace issues.
o Change short-circuit "||" operator to instead be "+" in order
to fix performance bug noted by "kraai" on LWN.
(http://lwn.net/Articles/324348/)
Changes from v1 (http://lkml.org/lkml/2009/1/13/440) include:
o This version depends on EMBEDDED as well as !SMP, as suggested
by Ingo.
o Updated rcu_needs_cpu() to unconditionally return zero,
permitting the CPU to enter dynticks-idle mode at any time.
This works because callbacks can be invoked upon entry to
dynticks-idle mode.
o Paul is now OK with this being included, based on a poll at
the Kernel Miniconf at linux.conf.au, where about ten people said
that they cared about saving 900 bytes on single-CPU systems.
o Applies to both mainline and tip/core/rcu.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Josh Triplett <josh@joshtriplett.org>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: avi@redhat.com
Cc: mtosatti@redhat.com
LKML-Reference: <12565226351355-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-26 10:03:50 +08:00
|
|
|
help
|
|
|
|
|
This option selects the RCU implementation that is
|
|
|
|
|
designed for UP systems from which real-time response
|
|
|
|
|
is not required. This option greatly reduces the
|
|
|
|
|
memory footprint of RCU.
|
|
|
|
|
|
2010-06-30 07:49:16 +08:00
|
|
|
config TINY_PREEMPT_RCU
|
|
|
|
|
bool "Preemptible UP-only small-memory-footprint RCU"
|
2011-06-09 07:31:33 +08:00
|
|
|
depends on PREEMPT && !SMP
|
2010-06-30 07:49:16 +08:00
|
|
|
help
|
|
|
|
|
This option selects the RCU implementation that is designed
|
|
|
|
|
for real-time UP systems. This option greatly reduces the
|
|
|
|
|
memory footprint of RCU.
|
|
|
|
|
|
2009-01-16 04:28:29 +08:00
|
|
|
endchoice
|
|
|
|
|
|
2010-06-30 07:49:16 +08:00
|
|
|
config PREEMPT_RCU
|
|
|
|
|
def_bool ( TREE_PREEMPT_RCU || TINY_PREEMPT_RCU )
|
|
|
|
|
help
|
|
|
|
|
This option enables preemptible-RCU code that is common between
|
|
|
|
|
the TREE_PREEMPT_RCU and TINY_PREEMPT_RCU implementations.
|
|
|
|
|
|
2012-07-12 02:26:30 +08:00
|
|
|
config RCU_USER_QS
|
|
|
|
|
bool "Consider userspace as in RCU extended quiescent state"
|
|
|
|
|
depends on HAVE_RCU_USER_QS && SMP
|
|
|
|
|
help
|
|
|
|
|
This option sets hooks on kernel / userspace boundaries and
|
|
|
|
|
puts RCU in extended quiescent state when the CPU runs in
|
|
|
|
|
userspace. It means that when a CPU runs in userspace, it is
|
|
|
|
|
excluded from the global RCU state machine and thus doesn't
|
2012-10-25 02:07:09 +08:00
|
|
|
try to keep the timer tick on for RCU.
|
2012-07-12 02:26:30 +08:00
|
|
|
|
2012-10-11 07:48:28 +08:00
|
|
|
Unless you want to hack and help the development of the full
|
2012-10-25 02:07:09 +08:00
|
|
|
tickless feature, you shouldn't enable this option. It also
|
|
|
|
|
adds unnecessary overhead.
|
2012-10-11 07:48:28 +08:00
|
|
|
|
|
|
|
|
If unsure say N
|
|
|
|
|
|
2012-07-12 02:26:40 +08:00
|
|
|
config RCU_USER_QS_FORCE
|
|
|
|
|
bool "Force userspace extended QS by default"
|
|
|
|
|
depends on RCU_USER_QS
|
|
|
|
|
help
|
|
|
|
|
Set the hooks in user/kernel boundaries by default in order to
|
|
|
|
|
test this feature that treats userspace as an extended quiescent
|
|
|
|
|
state until we have a real user like a full adaptive nohz option.
|
|
|
|
|
|
2012-10-11 07:48:28 +08:00
|
|
|
Unless you want to hack and help the development of the full
|
|
|
|
|
tickless feature, you shouldn't enable this option. It adds
|
|
|
|
|
unnecessary overhead.
|
|
|
|
|
|
|
|
|
|
If unsure say N
|
|
|
|
|
|
2009-01-16 04:28:29 +08:00
|
|
|
config RCU_FANOUT
|
|
|
|
|
int "Tree-based hierarchical RCU fanout value"
|
|
|
|
|
range 2 64 if 64BIT
|
|
|
|
|
range 2 32 if !64BIT
|
rcu: Merge preemptable-RCU functionality into hierarchical RCU
Create a kernel/rcutree_plugin.h file that contains definitions
for preemptable RCU (or, under the #else branch of the #ifdef,
empty definitions for the classic non-preemptable semantics).
These definitions fit into plugins defined in kernel/rcutree.c
for this purpose.
This variant of preemptable RCU uses a new algorithm whose
read-side expense is roughly that of classic hierarchical RCU
under CONFIG_PREEMPT. This new algorithm's update-side expense
is similar to that of classic hierarchical RCU, and, in absence
of read-side preemption or blocking, is exactly that of classic
hierarchical RCU. Perhaps more important, this new algorithm
has a much simpler implementation, saving well over 1,000 lines
of code compared to mainline's implementation of preemptable
RCU, which will hopefully be retired in favor of this new
algorithm.
The simplifications are obtained by maintaining per-task
nesting state for running tasks, and using a simple
lock-protected algorithm to handle accounting when tasks block
within RCU read-side critical sections, making use of lessons
learned while creating numerous user-level RCU implementations
over the past 18 months.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <12509746134003-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-23 04:56:52 +08:00
|
|
|
depends on TREE_RCU || TREE_PREEMPT_RCU
|
2009-01-16 04:28:29 +08:00
|
|
|
default 64 if 64BIT
|
|
|
|
|
default 32 if !64BIT
|
|
|
|
|
help
|
|
|
|
|
This option controls the fanout of hierarchical implementations
|
|
|
|
|
of RCU, allowing RCU to work efficiently on machines with
|
2010-08-05 08:31:12 +08:00
|
|
|
large numbers of CPUs. This value must be at least the fourth
|
|
|
|
|
root of NR_CPUS, which allows NR_CPUS to be insanely large.
|
|
|
|
|
The default value of RCU_FANOUT should be used for production
|
|
|
|
|
systems, but if you are stress-testing the RCU implementation
|
|
|
|
|
itself, small RCU_FANOUT values allow you to test large-system
|
|
|
|
|
code paths on small(er) systems.
|
2009-01-16 04:28:29 +08:00
|
|
|
|
|
|
|
|
Select a specific number if testing RCU itself.
|
|
|
|
|
Take the default if unsure.
|
|
|
|
|
|
2012-04-20 03:20:14 +08:00
|
|
|
config RCU_FANOUT_LEAF
|
|
|
|
|
int "Tree-based hierarchical RCU leaf-level fanout value"
|
|
|
|
|
range 2 RCU_FANOUT if 64BIT
|
|
|
|
|
range 2 RCU_FANOUT if !64BIT
|
|
|
|
|
depends on TREE_RCU || TREE_PREEMPT_RCU
|
|
|
|
|
default 16
|
|
|
|
|
help
|
|
|
|
|
This option controls the leaf-level fanout of hierarchical
|
|
|
|
|
implementations of RCU, and allows trading off cache misses
|
|
|
|
|
against lock contention. Systems that synchronize their
|
|
|
|
|
scheduling-clock interrupts for energy-efficiency reasons will
|
|
|
|
|
want the default because the smaller leaf-level fanout keeps
|
|
|
|
|
lock contention levels acceptably low. Very large systems
|
|
|
|
|
(hundreds or thousands of CPUs) will instead want to set this
|
|
|
|
|
value to the maximum value possible in order to reduce the
|
|
|
|
|
number of cache misses incurred during RCU's grace-period
|
|
|
|
|
initialization. These systems tend to run CPU-bound, and thus
|
|
|
|
|
are not helped by synchronized interrupts, and thus tend to
|
|
|
|
|
skew them, which reduces lock contention enough that large
|
|
|
|
|
leaf-level fanouts work well.
|
|
|
|
|
|
|
|
|
|
Select a specific number if testing RCU itself.
|
|
|
|
|
|
|
|
|
|
Select the maximum permissible value for large systems.
|
|
|
|
|
|
|
|
|
|
Take the default if unsure.
|
|
|
|
|
|
2009-01-16 04:28:29 +08:00
|
|
|
config RCU_FANOUT_EXACT
|
|
|
|
|
bool "Disable tree-based hierarchical RCU auto-balancing"
|
rcu: Merge preemptable-RCU functionality into hierarchical RCU
Create a kernel/rcutree_plugin.h file that contains definitions
for preemptable RCU (or, under the #else branch of the #ifdef,
empty definitions for the classic non-preemptable semantics).
These definitions fit into plugins defined in kernel/rcutree.c
for this purpose.
This variant of preemptable RCU uses a new algorithm whose
read-side expense is roughly that of classic hierarchical RCU
under CONFIG_PREEMPT. This new algorithm's update-side expense
is similar to that of classic hierarchical RCU, and, in absence
of read-side preemption or blocking, is exactly that of classic
hierarchical RCU. Perhaps more important, this new algorithm
has a much simpler implementation, saving well over 1,000 lines
of code compared to mainline's implementation of preemptable
RCU, which will hopefully be retired in favor of this new
algorithm.
The simplifications are obtained by maintaining per-task
nesting state for running tasks, and using a simple
lock-protected algorithm to handle accounting when tasks block
within RCU read-side critical sections, making use of lessons
learned while creating numerous user-level RCU implementations
over the past 18 months.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <12509746134003-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-23 04:56:52 +08:00
|
|
|
depends on TREE_RCU || TREE_PREEMPT_RCU
|
2009-01-16 04:28:29 +08:00
|
|
|
default n
|
|
|
|
|
help
|
|
|
|
|
This option forces use of the exact RCU_FANOUT value specified,
|
|
|
|
|
regardless of imbalances in the hierarchy. This is useful for
|
|
|
|
|
testing RCU itself, and might one day be useful on systems with
|
|
|
|
|
strong NUMA behavior.
|
|
|
|
|
|
|
|
|
|
Without RCU_FANOUT_EXACT, the code will balance the hierarchy.
|
|
|
|
|
|
|
|
|
|
Say N if unsure.
|
|
|
|
|
|
2010-02-23 09:04:59 +08:00
|
|
|
config RCU_FAST_NO_HZ
|
|
|
|
|
bool "Accelerate last non-dyntick-idle CPU's grace periods"
|
2011-11-04 05:56:12 +08:00
|
|
|
depends on NO_HZ && SMP
|
2010-02-23 09:04:59 +08:00
|
|
|
default n
|
|
|
|
|
help
|
2012-10-08 00:26:13 +08:00
|
|
|
This option causes RCU to attempt to accelerate grace periods in
|
|
|
|
|
order to allow CPUs to enter dynticks-idle state more quickly.
|
|
|
|
|
On the other hand, this option increases the overhead of the
|
|
|
|
|
dynticks-idle checking, thus degrading scheduling latency.
|
|
|
|
|
|
|
|
|
|
Say Y if energy efficiency is critically important, and you don't
|
|
|
|
|
care about real-time response.
|
2010-02-23 09:04:59 +08:00
|
|
|
|
|
|
|
|
Say N if you are unsure.
|
|
|
|
|
|
2009-01-16 04:28:29 +08:00
|
|
|
config TREE_RCU_TRACE
|
rcu: Merge preemptable-RCU functionality into hierarchical RCU
Create a kernel/rcutree_plugin.h file that contains definitions
for preemptable RCU (or, under the #else branch of the #ifdef,
empty definitions for the classic non-preemptable semantics).
These definitions fit into plugins defined in kernel/rcutree.c
for this purpose.
This variant of preemptable RCU uses a new algorithm whose
read-side expense is roughly that of classic hierarchical RCU
under CONFIG_PREEMPT. This new algorithm's update-side expense
is similar to that of classic hierarchical RCU, and, in absence
of read-side preemption or blocking, is exactly that of classic
hierarchical RCU. Perhaps more important, this new algorithm
has a much simpler implementation, saving well over 1,000 lines
of code compared to mainline's implementation of preemptable
RCU, which will hopefully be retired in favor of this new
algorithm.
The simplifications are obtained by maintaining per-task
nesting state for running tasks, and using a simple
lock-protected algorithm to handle accounting when tasks block
within RCU read-side critical sections, making use of lessons
learned while creating numerous user-level RCU implementations
over the past 18 months.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <12509746134003-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-23 04:56:52 +08:00
|
|
|
def_bool RCU_TRACE && ( TREE_RCU || TREE_PREEMPT_RCU )
|
2009-01-16 04:28:29 +08:00
|
|
|
select DEBUG_FS
|
|
|
|
|
help
|
rcu: Merge preemptable-RCU functionality into hierarchical RCU
Create a kernel/rcutree_plugin.h file that contains definitions
for preemptable RCU (or, under the #else branch of the #ifdef,
empty definitions for the classic non-preemptable semantics).
These definitions fit into plugins defined in kernel/rcutree.c
for this purpose.
This variant of preemptable RCU uses a new algorithm whose
read-side expense is roughly that of classic hierarchical RCU
under CONFIG_PREEMPT. This new algorithm's update-side expense
is similar to that of classic hierarchical RCU, and, in absence
of read-side preemption or blocking, is exactly that of classic
hierarchical RCU. Perhaps more important, this new algorithm
has a much simpler implementation, saving well over 1,000 lines
of code compared to mainline's implementation of preemptable
RCU, which will hopefully be retired in favor of this new
algorithm.
The simplifications are obtained by maintaining per-task
nesting state for running tasks, and using a simple
lock-protected algorithm to handle accounting when tasks block
within RCU read-side critical sections, making use of lessons
learned while creating numerous user-level RCU implementations
over the past 18 months.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <12509746134003-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-23 04:56:52 +08:00
|
|
|
This option provides tracing for the TREE_RCU and
|
|
|
|
|
TREE_PREEMPT_RCU implementations, permitting Makefile to
|
|
|
|
|
trivially select kernel/rcutree_trace.c.
|
2009-01-16 04:28:29 +08:00
|
|
|
|
2010-09-28 08:25:23 +08:00
|
|
|
config RCU_BOOST
|
|
|
|
|
bool "Enable RCU priority boosting"
|
2011-02-08 04:47:15 +08:00
|
|
|
depends on RT_MUTEXES && PREEMPT_RCU
|
2010-09-28 08:25:23 +08:00
|
|
|
default n
|
|
|
|
|
help
|
|
|
|
|
This option boosts the priority of preempted RCU readers that
|
|
|
|
|
block the current preemptible RCU grace period for too long.
|
|
|
|
|
This option also prevents heavy loads from blocking RCU
|
|
|
|
|
callback invocation for all flavors of RCU.
|
|
|
|
|
|
|
|
|
|
Say Y here if you are working with real-time apps or heavy loads
|
|
|
|
|
Say N here if you are unsure.
|
|
|
|
|
|
|
|
|
|
config RCU_BOOST_PRIO
|
|
|
|
|
int "Real-time priority to boost RCU readers to"
|
|
|
|
|
range 1 99
|
|
|
|
|
depends on RCU_BOOST
|
|
|
|
|
default 1
|
|
|
|
|
help
|
2012-04-19 07:20:18 +08:00
|
|
|
This option specifies the real-time priority to which long-term
|
|
|
|
|
preempted RCU readers are to be boosted. If you are working
|
|
|
|
|
with a real-time application that has one or more CPU-bound
|
|
|
|
|
threads running at a real-time priority level, you should set
|
|
|
|
|
RCU_BOOST_PRIO to a priority higher then the highest-priority
|
|
|
|
|
real-time CPU-bound thread. The default RCU_BOOST_PRIO value
|
|
|
|
|
of 1 is appropriate in the common case, which is real-time
|
|
|
|
|
applications that do not have any CPU-bound threads.
|
|
|
|
|
|
|
|
|
|
Some real-time applications might not have a single real-time
|
|
|
|
|
thread that saturates a given CPU, but instead might have
|
|
|
|
|
multiple real-time threads that, taken together, fully utilize
|
|
|
|
|
that CPU. In this case, you should set RCU_BOOST_PRIO to
|
|
|
|
|
a priority higher than the lowest-priority thread that is
|
|
|
|
|
conspiring to prevent the CPU from running any non-real-time
|
|
|
|
|
tasks. For example, if one thread at priority 10 and another
|
|
|
|
|
thread at priority 5 are between themselves fully consuming
|
|
|
|
|
the CPU time on a given CPU, then RCU_BOOST_PRIO should be
|
|
|
|
|
set to priority 6 or higher.
|
2010-09-28 08:25:23 +08:00
|
|
|
|
|
|
|
|
Specify the real-time priority, or take the default if unsure.
|
|
|
|
|
|
|
|
|
|
config RCU_BOOST_DELAY
|
|
|
|
|
int "Milliseconds to delay boosting after RCU grace-period start"
|
|
|
|
|
range 0 3000
|
|
|
|
|
depends on RCU_BOOST
|
|
|
|
|
default 500
|
|
|
|
|
help
|
|
|
|
|
This option specifies the time to wait after the beginning of
|
|
|
|
|
a given grace period before priority-boosting preempted RCU
|
|
|
|
|
readers blocking that grace period. Note that any RCU reader
|
|
|
|
|
blocking an expedited RCU grace period is boosted immediately.
|
|
|
|
|
|
|
|
|
|
Accept the default if unsure.
|
|
|
|
|
|
2012-08-20 12:35:53 +08:00
|
|
|
config RCU_NOCB_CPU
|
|
|
|
|
bool "Offload RCU callback processing from boot-selected CPUs"
|
|
|
|
|
depends on TREE_RCU || TREE_PREEMPT_RCU
|
|
|
|
|
default n
|
|
|
|
|
help
|
|
|
|
|
Use this option to reduce OS jitter for aggressive HPC or
|
|
|
|
|
real-time workloads. It can also be used to offload RCU
|
|
|
|
|
callback invocation to energy-efficient CPUs in battery-powered
|
|
|
|
|
asymmetric multiprocessors.
|
|
|
|
|
|
|
|
|
|
This option offloads callback invocation from the set of
|
|
|
|
|
CPUs specified at boot time by the rcu_nocbs parameter.
|
|
|
|
|
For each such CPU, a kthread ("rcuoN") will be created to
|
|
|
|
|
invoke callbacks, where the "N" is the CPU being offloaded.
|
|
|
|
|
Nothing prevents this kthread from running on the specified
|
|
|
|
|
CPUs, but (1) the kthreads may be preempted between each
|
|
|
|
|
callback, and (2) affinity or cgroups can be used to force
|
|
|
|
|
the kthreads to run on whatever set of CPUs is desired.
|
|
|
|
|
|
|
|
|
|
Say Y here if you want reduced OS jitter on selected CPUs.
|
|
|
|
|
Say N here if you are unsure.
|
|
|
|
|
|
2009-01-16 04:28:29 +08:00
|
|
|
endmenu # "RCU Subsystem"
|
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
config IKCONFIG
|
2006-10-01 14:27:25 +08:00
|
|
|
tristate "Kernel .config support"
|
2005-04-17 06:20:36 +08:00
|
|
|
---help---
|
|
|
|
|
This option enables the complete Linux kernel ".config" file
|
|
|
|
|
contents to be saved in the kernel. It provides documentation
|
|
|
|
|
of which kernel options are used in a running kernel or in an
|
|
|
|
|
on-disk kernel. This information can be extracted from the kernel
|
|
|
|
|
image file with the script scripts/extract-ikconfig and used as
|
|
|
|
|
input to rebuild the current kernel or to build another kernel.
|
|
|
|
|
It can also be extracted from a running kernel by reading
|
|
|
|
|
/proc/config.gz if enabled (below).
|
|
|
|
|
|
|
|
|
|
config IKCONFIG_PROC
|
|
|
|
|
bool "Enable access to .config through /proc/config.gz"
|
|
|
|
|
depends on IKCONFIG && PROC_FS
|
|
|
|
|
---help---
|
|
|
|
|
This option enables access to the kernel configuration file
|
|
|
|
|
through /proc/config.gz.
|
|
|
|
|
|
2007-05-08 15:31:15 +08:00
|
|
|
config LOG_BUF_SHIFT
|
|
|
|
|
int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
|
|
|
|
|
range 12 21
|
2008-04-29 15:58:58 +08:00
|
|
|
default 17
|
2007-05-08 15:31:15 +08:00
|
|
|
help
|
|
|
|
|
Select kernel log buffer size as a power of 2.
|
2008-04-29 15:58:58 +08:00
|
|
|
Examples:
|
|
|
|
|
17 => 128 KB
|
|
|
|
|
16 => 64 KB
|
|
|
|
|
15 => 32 KB
|
|
|
|
|
14 => 16 KB
|
2007-05-08 15:31:15 +08:00
|
|
|
13 => 8 KB
|
|
|
|
|
12 => 4 KB
|
|
|
|
|
|
2008-05-06 05:19:50 +08:00
|
|
|
#
|
|
|
|
|
# Architectures with an unreliable sched_clock() should select this:
|
|
|
|
|
#
|
|
|
|
|
config HAVE_UNSTABLE_SCHED_CLOCK
|
|
|
|
|
bool
|
|
|
|
|
|
2009-01-16 05:50:58 +08:00
|
|
|
menuconfig CGROUPS
|
|
|
|
|
boolean "Control Group support"
|
2010-03-11 07:22:20 +08:00
|
|
|
depends on EVENTFD
|
2009-01-08 10:07:30 +08:00
|
|
|
help
|
2009-01-16 05:50:58 +08:00
|
|
|
This option adds support for grouping sets of processes together, for
|
2009-01-08 10:07:30 +08:00
|
|
|
use with process control subsystems such as Cpusets, CFS, memory
|
|
|
|
|
controls or device isolation.
|
|
|
|
|
See
|
|
|
|
|
- Documentation/scheduler/sched-design-CFS.txt (CFS)
|
2009-01-16 05:50:59 +08:00
|
|
|
- Documentation/cgroups/ (features for grouping, isolation
|
|
|
|
|
and resource control)
|
2009-01-08 10:07:30 +08:00
|
|
|
|
|
|
|
|
Say N if unsure.
|
|
|
|
|
|
2009-01-16 05:50:58 +08:00
|
|
|
if CGROUPS
|
|
|
|
|
|
2009-01-08 10:07:30 +08:00
|
|
|
config CGROUP_DEBUG
|
|
|
|
|
bool "Example debug cgroup subsystem"
|
|
|
|
|
default n
|
|
|
|
|
help
|
|
|
|
|
This option enables a simple cgroup subsystem that
|
|
|
|
|
exports useful debugging information about the cgroups
|
2009-01-16 05:50:58 +08:00
|
|
|
framework.
|
2009-01-08 10:07:30 +08:00
|
|
|
|
2009-01-16 05:50:58 +08:00
|
|
|
Say N if unsure.
|
2009-01-08 10:07:30 +08:00
|
|
|
|
|
|
|
|
config CGROUP_FREEZER
|
2009-01-16 05:50:58 +08:00
|
|
|
bool "Freezer cgroup subsystem"
|
|
|
|
|
help
|
|
|
|
|
Provides a way to freeze and unfreeze all tasks in a
|
2009-01-08 10:07:30 +08:00
|
|
|
cgroup.
|
|
|
|
|
|
|
|
|
|
config CGROUP_DEVICE
|
|
|
|
|
bool "Device controller for cgroups"
|
|
|
|
|
help
|
|
|
|
|
Provides a cgroup implementing whitelists for devices which
|
|
|
|
|
a process in the cgroup can mknod or open.
|
|
|
|
|
|
|
|
|
|
config CPUSETS
|
|
|
|
|
bool "Cpuset support"
|
|
|
|
|
help
|
|
|
|
|
This option will let you create and manage CPUSETs which
|
|
|
|
|
allow dynamically partitioning a system into sets of CPUs and
|
|
|
|
|
Memory Nodes and assigning tasks to run only within those sets.
|
|
|
|
|
This is primarily useful on large SMP or NUMA systems.
|
|
|
|
|
|
|
|
|
|
Say N if unsure.
|
|
|
|
|
|
2009-01-16 05:50:58 +08:00
|
|
|
config PROC_PID_CPUSET
|
|
|
|
|
bool "Include legacy /proc/<pid>/cpuset file"
|
|
|
|
|
depends on CPUSETS
|
|
|
|
|
default y
|
|
|
|
|
|
2007-12-03 03:04:49 +08:00
|
|
|
config CGROUP_CPUACCT
|
|
|
|
|
bool "Simple CPU accounting cgroup subsystem"
|
|
|
|
|
help
|
|
|
|
|
Provides a simple Resource Controller for monitoring the
|
2009-01-16 05:50:58 +08:00
|
|
|
total CPU consumed by the tasks in a cgroup.
|
2007-12-03 03:04:49 +08:00
|
|
|
|
2008-02-07 16:13:49 +08:00
|
|
|
config RESOURCE_COUNTERS
|
|
|
|
|
bool "Resource counters"
|
|
|
|
|
help
|
|
|
|
|
This option enables controller independent resource accounting
|
2009-01-16 05:50:58 +08:00
|
|
|
infrastructure that works with cgroups.
|
2008-02-07 16:13:49 +08:00
|
|
|
|
2012-08-01 07:43:02 +08:00
|
|
|
config MEMCG
|
2008-03-05 06:28:39 +08:00
|
|
|
bool "Memory Resource Controller for Control Groups"
|
2010-10-28 06:34:39 +08:00
|
|
|
depends on RESOURCE_COUNTERS
|
cgroups: add an owner to the mm_struct
Remove the mem_cgroup member from mm_struct and instead adds an owner.
This approach was suggested by Paul Menage. The advantage of this approach
is that, once the mm->owner is known, using the subsystem id, the cgroup
can be determined. It also allows several control groups that are
virtually grouped by mm_struct, to exist independent of the memory
controller i.e., without adding mem_cgroup's for each controller, to
mm_struct.
A new config option CONFIG_MM_OWNER is added and the memory resource
controller selects this config option.
This patch also adds cgroup callbacks to notify subsystems when mm->owner
changes. The mm_cgroup_changed callback is called with the task_lock() of
the new task held and is called just prior to changing the mm->owner.
I am indebted to Paul Menage for the several reviews of this patchset and
helping me make it lighter and simpler.
This patch was tested on a powerpc box, it was compiled with both the
MM_OWNER config turned on and off.
After the thread group leader exits, it's moved to init_css_state by
cgroup_exit(), thus all future charges from runnings threads would be
redirected to the init_css_set's subsystem.
Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Pavel Emelianov <xemul@openvz.org>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Sudhir Kumar <skumar@linux.vnet.ibm.com>
Cc: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Cc: Hirokazu Takahashi <taka@valinux.co.jp>
Cc: David Rientjes <rientjes@google.com>,
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Reviewed-by: Paul Menage <menage@google.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 16:00:16 +08:00
|
|
|
select MM_OWNER
|
2008-03-05 06:28:39 +08:00
|
|
|
help
|
2008-10-30 05:01:06 +08:00
|
|
|
Provides a memory resource controller that manages both anonymous
|
2009-02-04 17:12:08 +08:00
|
|
|
memory and page cache. (See Documentation/cgroups/memory.txt)
|
2008-03-05 06:28:39 +08:00
|
|
|
|
|
|
|
|
Note that setting this option increases fixed memory overhead
|
2008-10-30 05:01:06 +08:00
|
|
|
associated with each page of memory in the system. By this,
|
|
|
|
|
20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
|
|
|
|
|
usage tracking struct at boot. Total amount of this is printed out
|
|
|
|
|
at boot.
|
2008-03-05 06:28:39 +08:00
|
|
|
|
|
|
|
|
Only enable when you're ok with these trade offs and really
|
2008-10-30 05:01:06 +08:00
|
|
|
sure you need the memory resource controller. Even when you enable
|
|
|
|
|
this, you can set "cgroup_disable=memory" at your boot option to
|
|
|
|
|
disable memory resource controller and you can avoid overheads.
|
2009-01-08 10:07:35 +08:00
|
|
|
(and lose benefits of memory resource controller)
|
2008-03-05 06:28:39 +08:00
|
|
|
|
cgroups: add an owner to the mm_struct
Remove the mem_cgroup member from mm_struct and instead adds an owner.
This approach was suggested by Paul Menage. The advantage of this approach
is that, once the mm->owner is known, using the subsystem id, the cgroup
can be determined. It also allows several control groups that are
virtually grouped by mm_struct, to exist independent of the memory
controller i.e., without adding mem_cgroup's for each controller, to
mm_struct.
A new config option CONFIG_MM_OWNER is added and the memory resource
controller selects this config option.
This patch also adds cgroup callbacks to notify subsystems when mm->owner
changes. The mm_cgroup_changed callback is called with the task_lock() of
the new task held and is called just prior to changing the mm->owner.
I am indebted to Paul Menage for the several reviews of this patchset and
helping me make it lighter and simpler.
This patch was tested on a powerpc box, it was compiled with both the
MM_OWNER config turned on and off.
After the thread group leader exits, it's moved to init_css_state by
cgroup_exit(), thus all future charges from runnings threads would be
redirected to the init_css_set's subsystem.
Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Pavel Emelianov <xemul@openvz.org>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Sudhir Kumar <skumar@linux.vnet.ibm.com>
Cc: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Cc: Hirokazu Takahashi <taka@valinux.co.jp>
Cc: David Rientjes <rientjes@google.com>,
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Reviewed-by: Paul Menage <menage@google.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 16:00:16 +08:00
|
|
|
This config option also selects MM_OWNER config option, which
|
|
|
|
|
could in turn add some fork/exit overhead.
|
|
|
|
|
|
2012-08-01 07:43:02 +08:00
|
|
|
config MEMCG_SWAP
|
2010-08-11 09:02:56 +08:00
|
|
|
bool "Memory Resource Controller Swap Extension"
|
2012-08-01 07:43:02 +08:00
|
|
|
depends on MEMCG && SWAP
|
2009-01-08 10:07:57 +08:00
|
|
|
help
|
|
|
|
|
Add swap management feature to memory resource controller. When you
|
|
|
|
|
enable this, you can limit mem+swap usage per cgroup. In other words,
|
|
|
|
|
when you disable this, memory resource controller has no cares to
|
|
|
|
|
usage of swap...a process can exhaust all of the swap. This extension
|
|
|
|
|
is useful when you want to avoid exhaustion swap but this itself
|
|
|
|
|
adds more overheads and consumes memory for remembering information.
|
|
|
|
|
Especially if you use 32bit system or small memory system, please
|
|
|
|
|
be careful about enabling this. When memory resource controller
|
|
|
|
|
is disabled by boot option, this will be automatically disabled and
|
|
|
|
|
there will be no overhead from this. Even when you set this config=y,
|
2011-07-26 08:12:12 +08:00
|
|
|
if boot option "swapaccount=0" is set, swap will not be accounted.
|
2009-04-03 07:57:47 +08:00
|
|
|
Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
|
|
|
|
|
size is 4096bytes, 512k per 1Gbytes of swap.
|
2012-08-01 07:43:02 +08:00
|
|
|
config MEMCG_SWAP_ENABLED
|
2010-11-25 04:57:08 +08:00
|
|
|
bool "Memory Resource Controller Swap Extension enabled by default"
|
2012-08-01 07:43:02 +08:00
|
|
|
depends on MEMCG_SWAP
|
2010-11-25 04:57:08 +08:00
|
|
|
default y
|
|
|
|
|
help
|
|
|
|
|
Memory Resource Controller Swap Extension comes with its price in
|
|
|
|
|
a bigger memory consumption. General purpose distribution kernels
|
2010-12-18 05:32:36 +08:00
|
|
|
which want to enable the feature but keep it disabled by default
|
2010-11-25 04:57:08 +08:00
|
|
|
and let the user enable it by swapaccount boot command line
|
|
|
|
|
parameter should have this option unselected.
|
|
|
|
|
For those who want to have the feature enabled by default should
|
|
|
|
|
select this option (if, for some reason, they need to disable it
|
2011-07-26 08:12:12 +08:00
|
|
|
then swapaccount=0 does the trick).
|
2012-08-01 07:43:02 +08:00
|
|
|
config MEMCG_KMEM
|
2011-12-12 05:47:01 +08:00
|
|
|
bool "Memory Resource Controller Kernel Memory accounting (EXPERIMENTAL)"
|
2012-08-01 07:43:02 +08:00
|
|
|
depends on MEMCG && EXPERIMENTAL
|
2011-12-12 05:47:01 +08:00
|
|
|
default n
|
|
|
|
|
help
|
|
|
|
|
The Kernel Memory extension for Memory Resource Controller can limit
|
|
|
|
|
the amount of memory used by kernel objects in the system. Those are
|
|
|
|
|
fundamentally different from the entities handled by the standard
|
|
|
|
|
Memory Controller, which are page-based, and can be swapped. Users of
|
|
|
|
|
the kmem extension can use it to guarantee that no group of processes
|
|
|
|
|
will ever exhaust kernel resources alone.
|
2009-01-08 10:07:57 +08:00
|
|
|
|
2012-08-01 07:42:12 +08:00
|
|
|
config CGROUP_HUGETLB
|
|
|
|
|
bool "HugeTLB Resource Controller for Control Groups"
|
|
|
|
|
depends on RESOURCE_COUNTERS && HUGETLB_PAGE && EXPERIMENTAL
|
|
|
|
|
default n
|
|
|
|
|
help
|
|
|
|
|
Provides a cgroup Resource Controller for HugeTLB pages.
|
|
|
|
|
When you enable this, you can put a per cgroup limit on HugeTLB usage.
|
|
|
|
|
The limit is enforced during page fault. Since HugeTLB doesn't
|
|
|
|
|
support page reclaim, enforcing the limit at page fault time implies
|
|
|
|
|
that, the application will get SIGBUS signal if it tries to access
|
|
|
|
|
HugeTLB pages beyond its limit. This requires the application to know
|
|
|
|
|
beforehand how much HugeTLB pages it would require for its use. The
|
|
|
|
|
control group is tracked in the third page lru pointer. This means
|
|
|
|
|
that we cannot use the controller with huge page less than 3 pages.
|
|
|
|
|
|
2011-02-14 17:20:01 +08:00
|
|
|
config CGROUP_PERF
|
|
|
|
|
bool "Enable perf_event per-cpu per-container group (cgroup) monitoring"
|
|
|
|
|
depends on PERF_EVENTS && CGROUPS
|
|
|
|
|
help
|
|
|
|
|
This option extends the per-cpu mode to restrict monitoring to
|
2011-03-03 14:26:20 +08:00
|
|
|
threads which belong to the cgroup specified and run on the
|
2011-02-14 17:20:01 +08:00
|
|
|
designated cpu.
|
|
|
|
|
|
|
|
|
|
Say N if unsure.
|
|
|
|
|
|
2010-01-20 20:26:18 +08:00
|
|
|
menuconfig CGROUP_SCHED
|
|
|
|
|
bool "Group CPU scheduler"
|
|
|
|
|
default n
|
|
|
|
|
help
|
|
|
|
|
This feature lets CPU scheduler recognize task groups and control CPU
|
|
|
|
|
bandwidth allocation to such task groups. It uses cgroups to group
|
|
|
|
|
tasks.
|
|
|
|
|
|
|
|
|
|
if CGROUP_SCHED
|
|
|
|
|
config FAIR_GROUP_SCHED
|
|
|
|
|
bool "Group scheduling for SCHED_OTHER"
|
|
|
|
|
depends on CGROUP_SCHED
|
|
|
|
|
default CGROUP_SCHED
|
|
|
|
|
|
2011-07-22 00:43:28 +08:00
|
|
|
config CFS_BANDWIDTH
|
|
|
|
|
bool "CPU bandwidth provisioning for FAIR_GROUP_SCHED"
|
|
|
|
|
depends on EXPERIMENTAL
|
|
|
|
|
depends on FAIR_GROUP_SCHED
|
|
|
|
|
default n
|
|
|
|
|
help
|
|
|
|
|
This option allows users to define CPU bandwidth rates (limits) for
|
|
|
|
|
tasks running within the fair group scheduler. Groups with no limit
|
|
|
|
|
set are considered to be unconstrained and will run with no
|
|
|
|
|
restriction.
|
|
|
|
|
See tip/Documentation/scheduler/sched-bwc.txt for more information.
|
|
|
|
|
|
2010-01-20 20:26:18 +08:00
|
|
|
config RT_GROUP_SCHED
|
|
|
|
|
bool "Group scheduling for SCHED_RR/FIFO"
|
|
|
|
|
depends on EXPERIMENTAL
|
|
|
|
|
depends on CGROUP_SCHED
|
|
|
|
|
default n
|
|
|
|
|
help
|
|
|
|
|
This feature lets you explicitly allocate real CPU bandwidth
|
2010-03-24 13:17:19 +08:00
|
|
|
to task groups. If enabled, it will also make it impossible to
|
2010-01-20 20:26:18 +08:00
|
|
|
schedule realtime tasks for non-root users until you allocate
|
|
|
|
|
realtime bandwidth for them.
|
|
|
|
|
See Documentation/scheduler/sched-rt-group.txt for more information.
|
|
|
|
|
|
|
|
|
|
endif #CGROUP_SCHED
|
|
|
|
|
|
2010-04-27 01:27:56 +08:00
|
|
|
config BLK_CGROUP
|
2012-03-06 05:14:54 +08:00
|
|
|
bool "Block IO controller"
|
2010-10-28 06:34:39 +08:00
|
|
|
depends on BLOCK
|
2010-04-27 01:27:56 +08:00
|
|
|
default n
|
|
|
|
|
---help---
|
|
|
|
|
Generic block IO controller cgroup interface. This is the common
|
|
|
|
|
cgroup interface which should be used by various IO controlling
|
|
|
|
|
policies.
|
|
|
|
|
|
|
|
|
|
Currently, CFQ IO scheduler uses it to recognize task groups and
|
|
|
|
|
control disk bandwidth allocation (proportional time slice allocation)
|
2010-09-16 05:06:35 +08:00
|
|
|
to such task groups. It is also used by bio throttling logic in
|
|
|
|
|
block layer to implement upper limit in IO rates on a device.
|
2010-04-27 01:27:56 +08:00
|
|
|
|
|
|
|
|
This option only enables generic Block IO controller infrastructure.
|
2010-09-16 05:06:35 +08:00
|
|
|
One needs to also enable actual IO controlling logic/policy. For
|
2011-01-17 05:43:10 +08:00
|
|
|
enabling proportional weight division of disk bandwidth in CFQ, set
|
|
|
|
|
CONFIG_CFQ_GROUP_IOSCHED=y; for enabling throttling policy, set
|
2011-01-17 08:08:41 +08:00
|
|
|
CONFIG_BLK_DEV_THROTTLING=y.
|
2010-04-27 01:27:56 +08:00
|
|
|
|
|
|
|
|
See Documentation/cgroups/blkio-controller.txt for more information.
|
|
|
|
|
|
|
|
|
|
config DEBUG_BLK_CGROUP
|
|
|
|
|
bool "Enable Block IO controller debugging"
|
|
|
|
|
depends on BLK_CGROUP
|
|
|
|
|
default n
|
|
|
|
|
---help---
|
|
|
|
|
Enable some debugging help. Currently it exports additional stat
|
|
|
|
|
files in a cgroup which can be useful for debugging.
|
|
|
|
|
|
2009-01-16 05:50:58 +08:00
|
|
|
endif # CGROUPS
|
2009-01-08 10:07:57 +08:00
|
|
|
|
2012-01-13 09:20:49 +08:00
|
|
|
config CHECKPOINT_RESTORE
|
|
|
|
|
bool "Checkpoint/restore support" if EXPERT
|
|
|
|
|
default n
|
|
|
|
|
help
|
|
|
|
|
Enables additional kernel features in a sake of checkpoint/restore.
|
|
|
|
|
In particular it adds auxiliary prctl codes to setup process text,
|
|
|
|
|
data and heap segment sizes, and a few additional /proc filesystem
|
|
|
|
|
entries.
|
|
|
|
|
|
|
|
|
|
If unsure, say N here.
|
|
|
|
|
|
2010-10-28 06:34:38 +08:00
|
|
|
menuconfig NAMESPACES
|
2011-01-21 06:44:16 +08:00
|
|
|
bool "Namespaces support" if EXPERT
|
|
|
|
|
default !EXPERT
|
2008-02-08 20:18:19 +08:00
|
|
|
help
|
|
|
|
|
Provides the way to make tasks work with different objects using
|
|
|
|
|
the same id. For example same IPC id may refer to different objects
|
|
|
|
|
or same user id or pid may refer to different tasks when used in
|
|
|
|
|
different namespaces.
|
|
|
|
|
|
2010-10-28 06:34:38 +08:00
|
|
|
if NAMESPACES
|
|
|
|
|
|
2008-02-08 20:18:21 +08:00
|
|
|
config UTS_NS
|
|
|
|
|
bool "UTS namespace"
|
2010-10-28 06:34:37 +08:00
|
|
|
default y
|
2008-02-08 20:18:21 +08:00
|
|
|
help
|
|
|
|
|
In this namespace tasks see different info provided with the
|
|
|
|
|
uname() system call
|
|
|
|
|
|
2008-02-08 20:18:22 +08:00
|
|
|
config IPC_NS
|
|
|
|
|
bool "IPC namespace"
|
2010-10-28 06:34:38 +08:00
|
|
|
depends on (SYSVIPC || POSIX_MQUEUE)
|
2010-10-28 06:34:37 +08:00
|
|
|
default y
|
2008-02-08 20:18:22 +08:00
|
|
|
help
|
|
|
|
|
In this namespace tasks work with IPC ids which correspond to
|
2009-04-07 10:01:08 +08:00
|
|
|
different IPC objects in different namespaces.
|
2008-02-08 20:18:22 +08:00
|
|
|
|
2008-02-08 20:18:23 +08:00
|
|
|
config USER_NS
|
|
|
|
|
bool "User namespace (EXPERIMENTAL)"
|
2010-10-28 06:34:38 +08:00
|
|
|
depends on EXPERIMENTAL
|
2012-04-21 19:09:01 +08:00
|
|
|
depends on UIDGID_CONVERTED
|
2011-11-18 02:23:55 +08:00
|
|
|
select UIDGID_STRICT_TYPE_CHECKS
|
2012-04-21 19:09:01 +08:00
|
|
|
|
2011-11-18 02:23:55 +08:00
|
|
|
default n
|
2008-02-08 20:18:23 +08:00
|
|
|
help
|
|
|
|
|
This allows containers, i.e. vservers, to use user namespaces
|
|
|
|
|
to provide different user info for different servers.
|
|
|
|
|
If unsure, say N.
|
|
|
|
|
|
2008-02-08 20:18:24 +08:00
|
|
|
config PID_NS
|
2010-10-28 06:34:37 +08:00
|
|
|
bool "PID Namespaces"
|
2010-10-28 06:34:37 +08:00
|
|
|
default y
|
2008-02-08 20:18:24 +08:00
|
|
|
help
|
2008-07-06 20:48:02 +08:00
|
|
|
Support process id namespaces. This allows having multiple
|
2009-01-26 18:12:25 +08:00
|
|
|
processes with the same pid as long as they are in different
|
2008-02-08 20:18:24 +08:00
|
|
|
pid namespaces. This is a building block of containers.
|
|
|
|
|
|
2009-01-27 04:25:55 +08:00
|
|
|
config NET_NS
|
|
|
|
|
bool "Network namespace"
|
2010-10-28 06:34:38 +08:00
|
|
|
depends on NET
|
2010-10-28 06:34:37 +08:00
|
|
|
default y
|
2009-01-27 04:25:55 +08:00
|
|
|
help
|
|
|
|
|
Allow user space to create what appear to be multiple instances
|
|
|
|
|
of the network stack.
|
|
|
|
|
|
2010-10-28 06:34:38 +08:00
|
|
|
endif # NAMESPACES
|
|
|
|
|
|
2012-04-21 19:09:01 +08:00
|
|
|
config UIDGID_CONVERTED
|
|
|
|
|
# True if all of the selected software conmponents are known
|
|
|
|
|
# to have uid_t and gid_t converted to kuid_t and kgid_t
|
|
|
|
|
# where appropriate and are otherwise safe to use with
|
|
|
|
|
# the user namespace.
|
|
|
|
|
bool
|
|
|
|
|
default y
|
|
|
|
|
|
|
|
|
|
# Networking
|
|
|
|
|
depends on NET_9P = n
|
|
|
|
|
|
|
|
|
|
# Filesystems
|
|
|
|
|
depends on 9P_FS = n
|
|
|
|
|
depends on AFS_FS = n
|
|
|
|
|
depends on AUTOFS4_FS = n
|
|
|
|
|
depends on CEPH_FS = n
|
|
|
|
|
depends on CIFS = n
|
|
|
|
|
depends on CODA_FS = n
|
|
|
|
|
depends on FUSE_FS = n
|
|
|
|
|
depends on GFS2_FS = n
|
|
|
|
|
depends on NCP_FS = n
|
|
|
|
|
depends on NFSD = n
|
|
|
|
|
depends on NFS_FS = n
|
|
|
|
|
depends on OCFS2_FS = n
|
|
|
|
|
depends on XFS_FS = n
|
|
|
|
|
|
2011-11-18 02:23:55 +08:00
|
|
|
config UIDGID_STRICT_TYPE_CHECKS
|
|
|
|
|
bool "Require conversions between uid/gids and their internal representation"
|
2012-04-21 19:09:01 +08:00
|
|
|
depends on UIDGID_CONVERTED
|
2011-11-18 02:23:55 +08:00
|
|
|
default n
|
|
|
|
|
help
|
|
|
|
|
While the nececessary conversions are being added to all subsystems this option allows
|
|
|
|
|
the code to continue to build for unconverted subsystems.
|
|
|
|
|
|
|
|
|
|
Say Y here if you want the strict type checking enabled
|
|
|
|
|
|
sched: Add 'autogroup' scheduling feature: automated per session task groups
A recurring complaint from CFS users is that parallel kbuild has
a negative impact on desktop interactivity. This patch
implements an idea from Linus, to automatically create task
groups. Currently, only per session autogroups are implemented,
but the patch leaves the way open for enhancement.
Implementation: each task's signal struct contains an inherited
pointer to a refcounted autogroup struct containing a task group
pointer, the default for all tasks pointing to the
init_task_group. When a task calls setsid(), a new task group
is created, the process is moved into the new task group, and a
reference to the preveious task group is dropped. Child
processes inherit this task group thereafter, and increase it's
refcount. When the last thread of a process exits, the
process's reference is dropped, such that when the last process
referencing an autogroup exits, the autogroup is destroyed.
At runqueue selection time, IFF a task has no cgroup assignment,
its current autogroup is used.
Autogroup bandwidth is controllable via setting it's nice level
through the proc filesystem:
cat /proc/<pid>/autogroup
Displays the task's group and the group's nice level.
echo <nice level> > /proc/<pid>/autogroup
Sets the task group's shares to the weight of nice <level> task.
Setting nice level is rate limited for !admin users due to the
abuse risk of task group locking.
The feature is enabled from boot by default if
CONFIG_SCHED_AUTOGROUP=y is selected, but can be disabled via
the boot option noautogroup, and can also be turned on/off on
the fly via:
echo [01] > /proc/sys/kernel/sched_autogroup_enabled
... which will automatically move tasks to/from the root task group.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Paul Turner <pjt@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
[ Removed the task_group_path() debug code, and fixed !EVENTFD build failure. ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <1290281700.28711.9.camel@maggy.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-30 21:18:03 +08:00
|
|
|
config SCHED_AUTOGROUP
|
|
|
|
|
bool "Automatic process group scheduling"
|
|
|
|
|
select EVENTFD
|
|
|
|
|
select CGROUPS
|
|
|
|
|
select CGROUP_SCHED
|
|
|
|
|
select FAIR_GROUP_SCHED
|
|
|
|
|
help
|
|
|
|
|
This option optimizes the scheduler for common desktop workloads by
|
|
|
|
|
automatically creating and populating task groups. This separation
|
|
|
|
|
of workloads isolates aggressive CPU burners (like build jobs) from
|
|
|
|
|
desktop applications. Task group autogeneration is currently based
|
|
|
|
|
upon task session.
|
|
|
|
|
|
2010-10-28 06:34:41 +08:00
|
|
|
config MM_OWNER
|
|
|
|
|
bool
|
|
|
|
|
|
|
|
|
|
config SYSFS_DEPRECATED
|
2011-01-11 02:04:22 +08:00
|
|
|
bool "Enable deprecated sysfs features to support old userspace tools"
|
2010-10-28 06:34:41 +08:00
|
|
|
depends on SYSFS
|
|
|
|
|
default n
|
|
|
|
|
help
|
|
|
|
|
This option adds code that switches the layout of the "block" class
|
|
|
|
|
devices, to not show up in /sys/class/block/, but only in
|
|
|
|
|
/sys/block/.
|
|
|
|
|
|
|
|
|
|
This switch is only active when the sysfs.deprecated=1 boot option is
|
|
|
|
|
passed or the SYSFS_DEPRECATED_V2 option is set.
|
|
|
|
|
|
|
|
|
|
This option allows new kernels to run on old distributions and tools,
|
|
|
|
|
which might get confused by /sys/class/block/. Since 2007/2008 all
|
|
|
|
|
major distributions and tools handle this just fine.
|
|
|
|
|
|
|
|
|
|
Recent distributions and userspace tools after 2009/2010 depend on
|
|
|
|
|
the existence of /sys/class/block/, and will not work with this
|
|
|
|
|
option enabled.
|
|
|
|
|
|
|
|
|
|
Only if you are using a new kernel on an old distribution, you might
|
|
|
|
|
need to say Y here.
|
|
|
|
|
|
|
|
|
|
config SYSFS_DEPRECATED_V2
|
2011-01-11 02:04:22 +08:00
|
|
|
bool "Enable deprecated sysfs features by default"
|
2010-10-28 06:34:41 +08:00
|
|
|
default n
|
|
|
|
|
depends on SYSFS
|
|
|
|
|
depends on SYSFS_DEPRECATED
|
|
|
|
|
help
|
|
|
|
|
Enable deprecated sysfs by default.
|
|
|
|
|
|
|
|
|
|
See the CONFIG_SYSFS_DEPRECATED option for more details about this
|
|
|
|
|
option.
|
|
|
|
|
|
|
|
|
|
Only if you are using a new kernel on an old distribution, you might
|
|
|
|
|
need to say Y here. Even then, odds are you would not need it
|
|
|
|
|
enabled, you can always pass the boot option if absolutely necessary.
|
|
|
|
|
|
|
|
|
|
config RELAY
|
|
|
|
|
bool "Kernel->user space relay support (formerly relayfs)"
|
|
|
|
|
help
|
|
|
|
|
This option enables support for relay interface support in
|
|
|
|
|
certain file systems (such as debugfs).
|
|
|
|
|
It is designed to provide an efficient mechanism for tools and
|
|
|
|
|
facilities to relay large amounts of data from kernel space to
|
|
|
|
|
user space.
|
|
|
|
|
|
|
|
|
|
If unsure, say N.
|
|
|
|
|
|
2007-03-06 17:42:17 +08:00
|
|
|
config BLK_DEV_INITRD
|
|
|
|
|
bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
|
|
|
|
|
depends on BROKEN || !FRV
|
|
|
|
|
help
|
|
|
|
|
The initial RAM filesystem is a ramfs which is loaded by the
|
|
|
|
|
boot loader (loadlin or lilo) and that is mounted as root
|
|
|
|
|
before the normal boot procedure. It is typically used to
|
|
|
|
|
load modules needed to mount the "real" root file system,
|
|
|
|
|
etc. See <file:Documentation/initrd.txt> for details.
|
|
|
|
|
|
|
|
|
|
If RAM disk support (BLK_DEV_RAM) is also included, this
|
|
|
|
|
also enables initial RAM disk (initrd) support and adds
|
|
|
|
|
15 Kbytes (more on some other architectures) to the kernel size.
|
|
|
|
|
|
|
|
|
|
If unsure say Y.
|
|
|
|
|
|
2007-02-10 17:44:43 +08:00
|
|
|
if BLK_DEV_INITRD
|
|
|
|
|
|
2005-08-11 02:44:50 +08:00
|
|
|
source "usr/Kconfig"
|
|
|
|
|
|
2007-02-10 17:44:43 +08:00
|
|
|
endif
|
|
|
|
|
|
Move size optimization option outside of EMBEDDED menu, mark it EXPERIMENTAL
Also, disable on sparc64 - a number of people report breakage. Probably
a compiler bug, but it's quite possible that it tickles some latent
kernel problem too.
It still defaults to 'y' everywhere else (when enabled through
EXPERIMENTAL), and Dave Jones points out that Fedora (and RHEL4) has
been building with size optimizations for a long time on x86, x86-64,
ia64, s390, s390x, ppc32 and ppc64. So it is really only moderately
experimental, but the sparc64 breakage certainly shows that it can
trigger "issues".
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-15 10:52:21 +08:00
|
|
|
config CC_OPTIMIZE_FOR_SIZE
|
2008-04-28 07:39:43 +08:00
|
|
|
bool "Optimize for size"
|
Move size optimization option outside of EMBEDDED menu, mark it EXPERIMENTAL
Also, disable on sparc64 - a number of people report breakage. Probably
a compiler bug, but it's quite possible that it tickles some latent
kernel problem too.
It still defaults to 'y' everywhere else (when enabled through
EXPERIMENTAL), and Dave Jones points out that Fedora (and RHEL4) has
been building with size optimizations for a long time on x86, x86-64,
ia64, s390, s390x, ppc32 and ppc64. So it is really only moderately
experimental, but the sparc64 breakage certainly shows that it can
trigger "issues".
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-15 10:52:21 +08:00
|
|
|
help
|
|
|
|
|
Enabling this option will pass "-Os" instead of "-O2" to gcc
|
|
|
|
|
resulting in a smaller kernel.
|
|
|
|
|
|
2008-07-16 06:31:16 +08:00
|
|
|
If unsure, say Y.
|
Move size optimization option outside of EMBEDDED menu, mark it EXPERIMENTAL
Also, disable on sparc64 - a number of people report breakage. Probably
a compiler bug, but it's quite possible that it tickles some latent
kernel problem too.
It still defaults to 'y' everywhere else (when enabled through
EXPERIMENTAL), and Dave Jones points out that Fedora (and RHEL4) has
been building with size optimizations for a long time on x86, x86-64,
ia64, s390, s390x, ppc32 and ppc64. So it is really only moderately
experimental, but the sparc64 breakage certainly shows that it can
trigger "issues".
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-15 10:52:21 +08:00
|
|
|
|
2006-10-01 14:28:13 +08:00
|
|
|
config SYSCTL
|
|
|
|
|
bool
|
|
|
|
|
|
2009-03-11 03:55:46 +08:00
|
|
|
config ANON_INODES
|
|
|
|
|
bool
|
|
|
|
|
|
2011-01-21 06:44:16 +08:00
|
|
|
menuconfig EXPERT
|
|
|
|
|
bool "Configure standard kernel features (expert users)"
|
2011-06-06 09:23:58 +08:00
|
|
|
# Unhide debug options, to make the on-by-default options visible
|
|
|
|
|
select DEBUG_KERNEL
|
2005-04-17 06:20:36 +08:00
|
|
|
help
|
|
|
|
|
This option allows certain base kernel options and settings
|
|
|
|
|
to be disabled or tweaked. This is for specialized
|
|
|
|
|
environments which can tolerate a "non-standard" kernel.
|
|
|
|
|
Only use this if you really know what you are doing.
|
|
|
|
|
|
2012-10-09 07:28:08 +08:00
|
|
|
config HAVE_UID16
|
|
|
|
|
bool
|
|
|
|
|
|
2006-09-17 03:15:53 +08:00
|
|
|
config UID16
|
2011-01-21 06:44:16 +08:00
|
|
|
bool "Enable 16-bit UID system calls" if EXPERT
|
2012-10-09 07:28:08 +08:00
|
|
|
depends on HAVE_UID16
|
2006-09-17 03:15:53 +08:00
|
|
|
default y
|
|
|
|
|
help
|
|
|
|
|
This enables the legacy 16-bit UID syscall wrappers.
|
|
|
|
|
|
2006-09-27 16:51:04 +08:00
|
|
|
config SYSCTL_SYSCALL
|
2011-01-21 06:44:16 +08:00
|
|
|
bool "Sysctl syscall support" if EXPERT
|
2009-11-05 21:26:41 +08:00
|
|
|
depends on PROC_SYSCTL
|
2011-11-03 04:39:25 +08:00
|
|
|
default n
|
2006-09-27 16:51:04 +08:00
|
|
|
select SYSCTL
|
2006-09-17 03:15:53 +08:00
|
|
|
---help---
|
2006-11-09 09:44:51 +08:00
|
|
|
sys_sysctl uses binary paths that have been found challenging
|
|
|
|
|
to properly maintain and use. The interface in /proc/sys
|
|
|
|
|
using paths with ascii names is now the primary path to this
|
|
|
|
|
information.
|
2006-09-27 16:51:04 +08:00
|
|
|
|
2006-11-09 09:44:51 +08:00
|
|
|
Almost nothing using the binary sysctl interface so if you are
|
|
|
|
|
trying to save some space it is probably safe to disable this,
|
|
|
|
|
making your kernel marginally smaller.
|
2006-09-27 16:51:04 +08:00
|
|
|
|
2011-11-03 04:39:25 +08:00
|
|
|
If unsure say N here.
|
2006-09-17 03:15:53 +08:00
|
|
|
|
2012-10-09 07:28:16 +08:00
|
|
|
config SYSCTL_EXCEPTION_TRACE
|
|
|
|
|
bool
|
|
|
|
|
help
|
|
|
|
|
Enable support for /proc/sys/debug/exception-trace.
|
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
config KALLSYMS
|
2011-01-21 06:44:16 +08:00
|
|
|
bool "Load all symbols for debugging/ksymoops" if EXPERT
|
2005-04-17 06:20:36 +08:00
|
|
|
default y
|
|
|
|
|
help
|
|
|
|
|
Say Y here to let the kernel print out symbolic crash information and
|
|
|
|
|
symbolic stack backtraces. This increases the size of the kernel
|
|
|
|
|
somewhat, as all symbols have to be loaded into the kernel image.
|
|
|
|
|
|
|
|
|
|
config KALLSYMS_ALL
|
|
|
|
|
bool "Include all symbols in kallsyms"
|
|
|
|
|
depends on DEBUG_KERNEL && KALLSYMS
|
|
|
|
|
help
|
2011-04-05 18:24:57 +08:00
|
|
|
Normally kallsyms only contains the symbols of functions for nicer
|
|
|
|
|
OOPS messages and backtraces (i.e., symbols from the text and inittext
|
|
|
|
|
sections). This is sufficient for most cases. And only in very rare
|
|
|
|
|
cases (e.g., when a debugger is used) all symbols are required (e.g.,
|
|
|
|
|
names of variables from the data sections, etc).
|
|
|
|
|
|
|
|
|
|
This option makes sure that all symbols are loaded into the kernel
|
|
|
|
|
image (i.e., symbols from all sections) in cost of increased kernel
|
|
|
|
|
size (depending on the kernel configuration, it may be 300KiB or
|
|
|
|
|
something like this).
|
|
|
|
|
|
|
|
|
|
Say N unless you really need all symbols.
|
2005-05-01 23:59:02 +08:00
|
|
|
|
2005-11-17 03:27:07 +08:00
|
|
|
config HOTPLUG
|
2012-09-05 08:01:08 +08:00
|
|
|
def_bool y
|
2005-11-17 03:27:07 +08:00
|
|
|
|
2005-05-01 23:59:02 +08:00
|
|
|
config PRINTK
|
|
|
|
|
default y
|
2011-01-21 06:44:16 +08:00
|
|
|
bool "Enable support for printk" if EXPERT
|
2005-05-01 23:59:02 +08:00
|
|
|
help
|
|
|
|
|
This option enables normal printk support. Removing it
|
|
|
|
|
eliminates most of the message strings from the kernel image
|
|
|
|
|
and makes the kernel more or less silent. As this makes it
|
|
|
|
|
very difficult to diagnose system problems, saying N here is
|
|
|
|
|
strongly discouraged.
|
|
|
|
|
|
2005-05-01 23:59:01 +08:00
|
|
|
config BUG
|
2011-01-21 06:44:16 +08:00
|
|
|
bool "BUG() support" if EXPERT
|
2005-05-01 23:59:01 +08:00
|
|
|
default y
|
|
|
|
|
help
|
|
|
|
|
Disabling this option eliminates support for BUG and WARN, reducing
|
|
|
|
|
the size of your kernel image and potentially quietly ignoring
|
|
|
|
|
numerous fatal conditions. You should only consider disabling this
|
|
|
|
|
option for embedded systems with no facilities for reporting errors.
|
|
|
|
|
Just say Y.
|
|
|
|
|
|
2006-01-08 17:05:25 +08:00
|
|
|
config ELF_CORE
|
2012-10-05 08:15:23 +08:00
|
|
|
depends on COREDUMP
|
2006-01-08 17:05:25 +08:00
|
|
|
default y
|
2011-01-21 06:44:16 +08:00
|
|
|
bool "Enable ELF core dumps" if EXPERT
|
2006-01-08 17:05:25 +08:00
|
|
|
help
|
|
|
|
|
Enable support for generating core dumps. Disabling saves about 4k.
|
|
|
|
|
|
2011-06-02 02:05:09 +08:00
|
|
|
|
2008-05-07 18:39:56 +08:00
|
|
|
config PCSPKR_PLATFORM
|
2011-01-21 06:44:16 +08:00
|
|
|
bool "Enable PC-Speaker support" if EXPERT
|
2011-06-02 02:05:09 +08:00
|
|
|
depends on HAVE_PCSPKR_PLATFORM
|
2011-06-02 02:04:59 +08:00
|
|
|
select I8253_LOCK
|
2008-05-07 18:39:56 +08:00
|
|
|
default y
|
|
|
|
|
help
|
|
|
|
|
This option allows to disable the internal PC-Speaker
|
|
|
|
|
support, saving some memory.
|
|
|
|
|
|
2011-06-02 02:05:09 +08:00
|
|
|
config HAVE_PCSPKR_PLATFORM
|
|
|
|
|
bool
|
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
config BASE_FULL
|
|
|
|
|
default y
|
2011-01-21 06:44:16 +08:00
|
|
|
bool "Enable full-sized data structures for core" if EXPERT
|
2005-04-17 06:20:36 +08:00
|
|
|
help
|
|
|
|
|
Disabling this option reduces the size of miscellaneous core
|
|
|
|
|
kernel data structures. This saves memory on small machines,
|
|
|
|
|
but may reduce performance.
|
|
|
|
|
|
|
|
|
|
config FUTEX
|
2011-01-21 06:44:16 +08:00
|
|
|
bool "Enable futex support" if EXPERT
|
2005-04-17 06:20:36 +08:00
|
|
|
default y
|
2006-06-27 17:54:53 +08:00
|
|
|
select RT_MUTEXES
|
2005-04-17 06:20:36 +08:00
|
|
|
help
|
|
|
|
|
Disabling this option will cause the kernel to be built without
|
|
|
|
|
support for "fast userspace mutexes". The resulting kernel may not
|
|
|
|
|
run glibc-based applications correctly.
|
|
|
|
|
|
|
|
|
|
config EPOLL
|
2011-01-21 06:44:16 +08:00
|
|
|
bool "Enable eventpoll support" if EXPERT
|
2005-04-17 06:20:36 +08:00
|
|
|
default y
|
2007-07-31 15:39:10 +08:00
|
|
|
select ANON_INODES
|
2005-04-17 06:20:36 +08:00
|
|
|
help
|
|
|
|
|
Disabling this option will cause the kernel to be built without
|
|
|
|
|
support for epoll family of system calls.
|
|
|
|
|
|
signal/timer/event: signalfd core
This patch series implements the new signalfd() system call.
I took part of the original Linus code (and you know how badly it can be
broken :), and I added even more breakage ;) Signals are fetched from the same
signal queue used by the process, so signalfd will compete with standard
kernel delivery in dequeue_signal(). If you want to reliably fetch signals on
the signalfd file, you need to block them with sigprocmask(SIG_BLOCK). This
seems to be working fine on my Dual Opteron machine. I made a quick test
program for it:
http://www.xmailserver.org/signafd-test.c
The signalfd() system call implements signal delivery into a file descriptor
receiver. The signalfd file descriptor if created with the following API:
int signalfd(int ufd, const sigset_t *mask, size_t masksize);
The "ufd" parameter allows to change an existing signalfd sigmask, w/out going
to close/create cycle (Linus idea). Use "ufd" == -1 if you want a brand new
signalfd file.
The "mask" allows to specify the signal mask of signals that we are interested
in. The "masksize" parameter is the size of "mask".
The signalfd fd supports the poll(2) and read(2) system calls. The poll(2)
will return POLLIN when signals are available to be dequeued. As a direct
consequence of supporting the Linux poll subsystem, the signalfd fd can use
used together with epoll(2) too.
The read(2) system call will return a "struct signalfd_siginfo" structure in
the userspace supplied buffer. The return value is the number of bytes copied
in the supplied buffer, or -1 in case of error. The read(2) call can also
return 0, in case the sighand structure to which the signalfd was attached,
has been orphaned. The O_NONBLOCK flag is also supported, and read(2) will
return -EAGAIN in case no signal is available.
If the size of the buffer passed to read(2) is lower than sizeof(struct
signalfd_siginfo), -EINVAL is returned. A read from the signalfd can also
return -ERESTARTSYS in case a signal hits the process. The format of the
struct signalfd_siginfo is, and the valid fields depends of the (->code &
__SI_MASK) value, in the same way a struct siginfo would:
struct signalfd_siginfo {
__u32 signo; /* si_signo */
__s32 err; /* si_errno */
__s32 code; /* si_code */
__u32 pid; /* si_pid */
__u32 uid; /* si_uid */
__s32 fd; /* si_fd */
__u32 tid; /* si_fd */
__u32 band; /* si_band */
__u32 overrun; /* si_overrun */
__u32 trapno; /* si_trapno */
__s32 status; /* si_status */
__s32 svint; /* si_int */
__u64 svptr; /* si_ptr */
__u64 utime; /* si_utime */
__u64 stime; /* si_stime */
__u64 addr; /* si_addr */
};
[akpm@linux-foundation.org: fix signalfd_copyinfo() on i386]
Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-11 13:23:13 +08:00
|
|
|
config SIGNALFD
|
2011-01-21 06:44:16 +08:00
|
|
|
bool "Enable signalfd() system call" if EXPERT
|
2007-07-31 15:39:10 +08:00
|
|
|
select ANON_INODES
|
signal/timer/event: signalfd core
This patch series implements the new signalfd() system call.
I took part of the original Linus code (and you know how badly it can be
broken :), and I added even more breakage ;) Signals are fetched from the same
signal queue used by the process, so signalfd will compete with standard
kernel delivery in dequeue_signal(). If you want to reliably fetch signals on
the signalfd file, you need to block them with sigprocmask(SIG_BLOCK). This
seems to be working fine on my Dual Opteron machine. I made a quick test
program for it:
http://www.xmailserver.org/signafd-test.c
The signalfd() system call implements signal delivery into a file descriptor
receiver. The signalfd file descriptor if created with the following API:
int signalfd(int ufd, const sigset_t *mask, size_t masksize);
The "ufd" parameter allows to change an existing signalfd sigmask, w/out going
to close/create cycle (Linus idea). Use "ufd" == -1 if you want a brand new
signalfd file.
The "mask" allows to specify the signal mask of signals that we are interested
in. The "masksize" parameter is the size of "mask".
The signalfd fd supports the poll(2) and read(2) system calls. The poll(2)
will return POLLIN when signals are available to be dequeued. As a direct
consequence of supporting the Linux poll subsystem, the signalfd fd can use
used together with epoll(2) too.
The read(2) system call will return a "struct signalfd_siginfo" structure in
the userspace supplied buffer. The return value is the number of bytes copied
in the supplied buffer, or -1 in case of error. The read(2) call can also
return 0, in case the sighand structure to which the signalfd was attached,
has been orphaned. The O_NONBLOCK flag is also supported, and read(2) will
return -EAGAIN in case no signal is available.
If the size of the buffer passed to read(2) is lower than sizeof(struct
signalfd_siginfo), -EINVAL is returned. A read from the signalfd can also
return -ERESTARTSYS in case a signal hits the process. The format of the
struct signalfd_siginfo is, and the valid fields depends of the (->code &
__SI_MASK) value, in the same way a struct siginfo would:
struct signalfd_siginfo {
__u32 signo; /* si_signo */
__s32 err; /* si_errno */
__s32 code; /* si_code */
__u32 pid; /* si_pid */
__u32 uid; /* si_uid */
__s32 fd; /* si_fd */
__u32 tid; /* si_fd */
__u32 band; /* si_band */
__u32 overrun; /* si_overrun */
__u32 trapno; /* si_trapno */
__s32 status; /* si_status */
__s32 svint; /* si_int */
__u64 svptr; /* si_ptr */
__u64 utime; /* si_utime */
__u64 stime; /* si_stime */
__u64 addr; /* si_addr */
};
[akpm@linux-foundation.org: fix signalfd_copyinfo() on i386]
Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-11 13:23:13 +08:00
|
|
|
default y
|
|
|
|
|
help
|
|
|
|
|
Enable the signalfd() system call that allows to receive signals
|
|
|
|
|
on a file descriptor.
|
|
|
|
|
|
|
|
|
|
If unsure, say Y.
|
|
|
|
|
|
signal/timer/event: timerfd core
This patch introduces a new system call for timers events delivered though
file descriptors. This allows timer event to be used with standard POSIX
poll(2), select(2) and read(2). As a consequence of supporting the Linux
f_op->poll subsystem, they can be used with epoll(2) too.
The system call is defined as:
int timerfd(int ufd, int clockid, int flags, const struct itimerspec *utmr);
The "ufd" parameter allows for re-use (re-programming) of an existing timerfd
w/out going through the close/open cycle (same as signalfd). If "ufd" is -1,
s new file descriptor will be created, otherwise the existing "ufd" will be
re-programmed.
The "clockid" parameter is either CLOCK_MONOTONIC or CLOCK_REALTIME. The time
specified in the "utmr->it_value" parameter is the expiry time for the timer.
If the TFD_TIMER_ABSTIME flag is set in "flags", this is an absolute time,
otherwise it's a relative time.
If the time specified in the "utmr->it_interval" is not zero (.tv_sec == 0,
tv_nsec == 0), this is the period at which the following ticks should be
generated.
The "utmr->it_interval" should be set to zero if only one tick is requested.
Setting the "utmr->it_value" to zero will disable the timer, or will create a
timerfd without the timer enabled.
The function returns the new (or same, in case "ufd" is a valid timerfd
descriptor) file, or -1 in case of error.
As stated before, the timerfd file descriptor supports poll(2), select(2) and
epoll(2). When a timer event happened on the timerfd, a POLLIN mask will be
returned.
The read(2) call can be used, and it will return a u32 variable holding the
number of "ticks" that happened on the interface since the last call to
read(2). The read(2) call supportes the O_NONBLOCK flag too, and EAGAIN will
be returned if no ticks happened.
A quick test program, shows timerfd working correctly on my amd64 box:
http://www.xmailserver.org/timerfd-test.c
[akpm@linux-foundation.org: add sys_timerfd to sys_ni.c]
Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-11 13:23:16 +08:00
|
|
|
config TIMERFD
|
2011-01-21 06:44:16 +08:00
|
|
|
bool "Enable timerfd() system call" if EXPERT
|
2007-07-31 15:39:10 +08:00
|
|
|
select ANON_INODES
|
signal/timer/event: timerfd core
This patch introduces a new system call for timers events delivered though
file descriptors. This allows timer event to be used with standard POSIX
poll(2), select(2) and read(2). As a consequence of supporting the Linux
f_op->poll subsystem, they can be used with epoll(2) too.
The system call is defined as:
int timerfd(int ufd, int clockid, int flags, const struct itimerspec *utmr);
The "ufd" parameter allows for re-use (re-programming) of an existing timerfd
w/out going through the close/open cycle (same as signalfd). If "ufd" is -1,
s new file descriptor will be created, otherwise the existing "ufd" will be
re-programmed.
The "clockid" parameter is either CLOCK_MONOTONIC or CLOCK_REALTIME. The time
specified in the "utmr->it_value" parameter is the expiry time for the timer.
If the TFD_TIMER_ABSTIME flag is set in "flags", this is an absolute time,
otherwise it's a relative time.
If the time specified in the "utmr->it_interval" is not zero (.tv_sec == 0,
tv_nsec == 0), this is the period at which the following ticks should be
generated.
The "utmr->it_interval" should be set to zero if only one tick is requested.
Setting the "utmr->it_value" to zero will disable the timer, or will create a
timerfd without the timer enabled.
The function returns the new (or same, in case "ufd" is a valid timerfd
descriptor) file, or -1 in case of error.
As stated before, the timerfd file descriptor supports poll(2), select(2) and
epoll(2). When a timer event happened on the timerfd, a POLLIN mask will be
returned.
The read(2) call can be used, and it will return a u32 variable holding the
number of "ticks" that happened on the interface since the last call to
read(2). The read(2) call supportes the O_NONBLOCK flag too, and EAGAIN will
be returned if no ticks happened.
A quick test program, shows timerfd working correctly on my amd64 box:
http://www.xmailserver.org/timerfd-test.c
[akpm@linux-foundation.org: add sys_timerfd to sys_ni.c]
Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-11 13:23:16 +08:00
|
|
|
default y
|
|
|
|
|
help
|
|
|
|
|
Enable the timerfd() system call that allows to receive timer
|
|
|
|
|
events on a file descriptor.
|
|
|
|
|
|
|
|
|
|
If unsure, say Y.
|
|
|
|
|
|
signal/timer/event: eventfd core
This is a very simple and light file descriptor, that can be used as event
wait/dispatch by userspace (both wait and dispatch) and by the kernel
(dispatch only). It can be used instead of pipe(2) in all cases where those
would simply be used to signal events. Their kernel overhead is much lower
than pipes, and they do not consume two fds. When used in the kernel, it can
offer an fd-bridge to enable, for example, functionalities like KAIO or
syslets/threadlets to signal to an fd the completion of certain operations.
But more in general, an eventfd can be used by the kernel to signal readiness,
in a POSIX poll/select way, of interfaces that would otherwise be incompatible
with it. The API is:
int eventfd(unsigned int count);
The eventfd API accepts an initial "count" parameter, and returns an eventfd
fd. It supports poll(2) (POLLIN, POLLOUT, POLLERR), read(2) and write(2).
The POLLIN flag is raised when the internal counter is greater than zero.
The POLLOUT flag is raised when at least a value of "1" can be written to the
internal counter.
The POLLERR flag is raised when an overflow in the counter value is detected.
The write(2) operation can never overflow the counter, since it blocks (unless
O_NONBLOCK is set, in which case -EAGAIN is returned).
But the eventfd_signal() function can do it, since it's supposed to not sleep
during its operation.
The read(2) function reads the __u64 counter value, and reset the internal
value to zero. If the value read is equal to (__u64) -1, an overflow happened
on the internal counter (due to 2^64 eventfd_signal() posts that has never
been retired - unlickely, but possible).
The write(2) call writes an __u64 count value, and adds it to the current
counter. The eventfd fd supports O_NONBLOCK also.
On the kernel side, we have:
struct file *eventfd_fget(int fd);
int eventfd_signal(struct file *file, unsigned int n);
The eventfd_fget() should be called to get a struct file* from an eventfd fd
(this is an fget() + check of f_op being an eventfd fops pointer).
The kernel can then call eventfd_signal() every time it wants to post an event
to userspace. The eventfd_signal() function can be called from any context.
An eventfd() simple test and bench is available here:
http://www.xmailserver.org/eventfd-bench.c
This is the eventfd-based version of pipetest-4 (pipe(2) based):
http://www.xmailserver.org/pipetest-4.c
Not that performance matters much in the eventfd case, but eventfd-bench
shows almost as double as performance than pipetest-4.
[akpm@linux-foundation.org: fix i386 build]
[akpm@linux-foundation.org: add sys_eventfd to sys_ni.c]
Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-11 13:23:19 +08:00
|
|
|
config EVENTFD
|
2011-01-21 06:44:16 +08:00
|
|
|
bool "Enable eventfd() system call" if EXPERT
|
2007-07-31 15:39:10 +08:00
|
|
|
select ANON_INODES
|
signal/timer/event: eventfd core
This is a very simple and light file descriptor, that can be used as event
wait/dispatch by userspace (both wait and dispatch) and by the kernel
(dispatch only). It can be used instead of pipe(2) in all cases where those
would simply be used to signal events. Their kernel overhead is much lower
than pipes, and they do not consume two fds. When used in the kernel, it can
offer an fd-bridge to enable, for example, functionalities like KAIO or
syslets/threadlets to signal to an fd the completion of certain operations.
But more in general, an eventfd can be used by the kernel to signal readiness,
in a POSIX poll/select way, of interfaces that would otherwise be incompatible
with it. The API is:
int eventfd(unsigned int count);
The eventfd API accepts an initial "count" parameter, and returns an eventfd
fd. It supports poll(2) (POLLIN, POLLOUT, POLLERR), read(2) and write(2).
The POLLIN flag is raised when the internal counter is greater than zero.
The POLLOUT flag is raised when at least a value of "1" can be written to the
internal counter.
The POLLERR flag is raised when an overflow in the counter value is detected.
The write(2) operation can never overflow the counter, since it blocks (unless
O_NONBLOCK is set, in which case -EAGAIN is returned).
But the eventfd_signal() function can do it, since it's supposed to not sleep
during its operation.
The read(2) function reads the __u64 counter value, and reset the internal
value to zero. If the value read is equal to (__u64) -1, an overflow happened
on the internal counter (due to 2^64 eventfd_signal() posts that has never
been retired - unlickely, but possible).
The write(2) call writes an __u64 count value, and adds it to the current
counter. The eventfd fd supports O_NONBLOCK also.
On the kernel side, we have:
struct file *eventfd_fget(int fd);
int eventfd_signal(struct file *file, unsigned int n);
The eventfd_fget() should be called to get a struct file* from an eventfd fd
(this is an fget() + check of f_op being an eventfd fops pointer).
The kernel can then call eventfd_signal() every time it wants to post an event
to userspace. The eventfd_signal() function can be called from any context.
An eventfd() simple test and bench is available here:
http://www.xmailserver.org/eventfd-bench.c
This is the eventfd-based version of pipetest-4 (pipe(2) based):
http://www.xmailserver.org/pipetest-4.c
Not that performance matters much in the eventfd case, but eventfd-bench
shows almost as double as performance than pipetest-4.
[akpm@linux-foundation.org: fix i386 build]
[akpm@linux-foundation.org: add sys_eventfd to sys_ni.c]
Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-11 13:23:19 +08:00
|
|
|
default y
|
|
|
|
|
help
|
|
|
|
|
Enable the eventfd() system call that allows to receive both
|
|
|
|
|
kernel notification (ie. KAIO) or userspace notifications.
|
|
|
|
|
|
|
|
|
|
If unsure, say Y.
|
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
config SHMEM
|
2011-01-21 06:44:16 +08:00
|
|
|
bool "Use full shmem filesystem" if EXPERT
|
2005-04-17 06:20:36 +08:00
|
|
|
default y
|
|
|
|
|
depends on MMU
|
|
|
|
|
help
|
|
|
|
|
The shmem is an internal filesystem used to manage shared memory.
|
|
|
|
|
It is backed by swap and manages resource limits. It is also exported
|
|
|
|
|
to userspace as tmpfs if TMPFS is enabled. Disabling this
|
|
|
|
|
option replaces shmem and tmpfs with the much simpler ramfs code,
|
|
|
|
|
which may be appropriate on small systems without swap.
|
|
|
|
|
|
2008-10-16 13:05:12 +08:00
|
|
|
config AIO
|
2011-01-21 06:44:16 +08:00
|
|
|
bool "Enable AIO support" if EXPERT
|
2008-10-16 13:05:12 +08:00
|
|
|
default y
|
|
|
|
|
help
|
|
|
|
|
This option enables POSIX asynchronous I/O which may by used
|
|
|
|
|
by some high performance threaded applications. Disabling
|
|
|
|
|
this option saves about 7k.
|
|
|
|
|
|
2011-04-27 03:33:21 +08:00
|
|
|
config EMBEDDED
|
|
|
|
|
bool "Embedded system"
|
|
|
|
|
select EXPERT
|
|
|
|
|
help
|
|
|
|
|
This option should be enabled if compiling the kernel for
|
|
|
|
|
an embedded system so certain expert options are available
|
|
|
|
|
for configuration.
|
|
|
|
|
|
perf: Do the big rename: Performance Counters -> Performance Events
Bye-bye Performance Counters, welcome Performance Events!
In the past few months the perfcounters subsystem has grown out its
initial role of counting hardware events, and has become (and is
becoming) a much broader generic event enumeration, reporting, logging,
monitoring, analysis facility.
Naming its core object 'perf_counter' and naming the subsystem
'perfcounters' has become more and more of a misnomer. With pending
code like hw-breakpoints support the 'counter' name is less and
less appropriate.
All in one, we've decided to rename the subsystem to 'performance
events' and to propagate this rename through all fields, variables
and API names. (in an ABI compatible fashion)
The word 'event' is also a bit shorter than 'counter' - which makes
it slightly more convenient to write/handle as well.
Thanks goes to Stephane Eranian who first observed this misnomer and
suggested a rename.
User-space tooling and ABI compatibility is not affected - this patch
should be function-invariant. (Also, defconfigs were not touched to
keep the size down.)
This patch has been generated via the following script:
FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')
sed -i \
-e 's/PERF_EVENT_/PERF_RECORD_/g' \
-e 's/PERF_COUNTER/PERF_EVENT/g' \
-e 's/perf_counter/perf_event/g' \
-e 's/nb_counters/nb_events/g' \
-e 's/swcounter/swevent/g' \
-e 's/tpcounter_event/tp_event/g' \
$FILES
for N in $(find . -name perf_counter.[ch]); do
M=$(echo $N | sed 's/perf_counter/perf_event/g')
mv $N $M
done
FILES=$(find . -name perf_event.*)
sed -i \
-e 's/COUNTER_MASK/REG_MASK/g' \
-e 's/COUNTER/EVENT/g' \
-e 's/\<event\>/event_id/g' \
-e 's/counter/event/g' \
-e 's/Counter/Event/g' \
$FILES
... to keep it as correct as possible. This script can also be
used by anyone who has pending perfcounters patches - it converts
a Linux kernel tree over to the new naming. We tried to time this
change to the point in time where the amount of pending patches
is the smallest: the end of the merge window.
Namespace clashes were fixed up in a preparatory patch - and some
stylistic fallout will be fixed up in a subsequent patch.
( NOTE: 'counters' are still the proper terminology when we deal
with hardware registers - and these sed scripts are a bit
over-eager in renaming them. I've undone some of that, but
in case there's something left where 'counter' would be
better than 'event' we can undo that on an individual basis
instead of touching an otherwise nicely automated patch. )
Suggested-by: Stephane Eranian <eranian@google.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Paul Mackerras <paulus@samba.org>
Reviewed-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <linux-arch@vger.kernel.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-21 18:02:48 +08:00
|
|
|
config HAVE_PERF_EVENTS
|
2008-12-05 03:12:29 +08:00
|
|
|
bool
|
2009-06-13 01:17:43 +08:00
|
|
|
help
|
|
|
|
|
See tools/perf/design.txt for details.
|
2008-12-05 03:12:29 +08:00
|
|
|
|
2009-09-21 22:08:49 +08:00
|
|
|
config PERF_USE_VMALLOC
|
|
|
|
|
bool
|
|
|
|
|
help
|
|
|
|
|
See tools/perf/design.txt for details
|
|
|
|
|
|
2009-09-21 18:20:38 +08:00
|
|
|
menu "Kernel Performance Events And Counters"
|
2008-12-05 03:12:29 +08:00
|
|
|
|
perf: Do the big rename: Performance Counters -> Performance Events
Bye-bye Performance Counters, welcome Performance Events!
In the past few months the perfcounters subsystem has grown out its
initial role of counting hardware events, and has become (and is
becoming) a much broader generic event enumeration, reporting, logging,
monitoring, analysis facility.
Naming its core object 'perf_counter' and naming the subsystem
'perfcounters' has become more and more of a misnomer. With pending
code like hw-breakpoints support the 'counter' name is less and
less appropriate.
All in one, we've decided to rename the subsystem to 'performance
events' and to propagate this rename through all fields, variables
and API names. (in an ABI compatible fashion)
The word 'event' is also a bit shorter than 'counter' - which makes
it slightly more convenient to write/handle as well.
Thanks goes to Stephane Eranian who first observed this misnomer and
suggested a rename.
User-space tooling and ABI compatibility is not affected - this patch
should be function-invariant. (Also, defconfigs were not touched to
keep the size down.)
This patch has been generated via the following script:
FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')
sed -i \
-e 's/PERF_EVENT_/PERF_RECORD_/g' \
-e 's/PERF_COUNTER/PERF_EVENT/g' \
-e 's/perf_counter/perf_event/g' \
-e 's/nb_counters/nb_events/g' \
-e 's/swcounter/swevent/g' \
-e 's/tpcounter_event/tp_event/g' \
$FILES
for N in $(find . -name perf_counter.[ch]); do
M=$(echo $N | sed 's/perf_counter/perf_event/g')
mv $N $M
done
FILES=$(find . -name perf_event.*)
sed -i \
-e 's/COUNTER_MASK/REG_MASK/g' \
-e 's/COUNTER/EVENT/g' \
-e 's/\<event\>/event_id/g' \
-e 's/counter/event/g' \
-e 's/Counter/Event/g' \
$FILES
... to keep it as correct as possible. This script can also be
used by anyone who has pending perfcounters patches - it converts
a Linux kernel tree over to the new naming. We tried to time this
change to the point in time where the amount of pending patches
is the smallest: the end of the merge window.
Namespace clashes were fixed up in a preparatory patch - and some
stylistic fallout will be fixed up in a subsequent patch.
( NOTE: 'counters' are still the proper terminology when we deal
with hardware registers - and these sed scripts are a bit
over-eager in renaming them. I've undone some of that, but
in case there's something left where 'counter' would be
better than 'event' we can undo that on an individual basis
instead of touching an otherwise nicely automated patch. )
Suggested-by: Stephane Eranian <eranian@google.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Paul Mackerras <paulus@samba.org>
Reviewed-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <linux-arch@vger.kernel.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-21 18:02:48 +08:00
|
|
|
config PERF_EVENTS
|
2009-09-21 18:20:38 +08:00
|
|
|
bool "Kernel performance events and counters"
|
2012-04-06 00:24:44 +08:00
|
|
|
default y if PROFILING
|
perf: Do the big rename: Performance Counters -> Performance Events
Bye-bye Performance Counters, welcome Performance Events!
In the past few months the perfcounters subsystem has grown out its
initial role of counting hardware events, and has become (and is
becoming) a much broader generic event enumeration, reporting, logging,
monitoring, analysis facility.
Naming its core object 'perf_counter' and naming the subsystem
'perfcounters' has become more and more of a misnomer. With pending
code like hw-breakpoints support the 'counter' name is less and
less appropriate.
All in one, we've decided to rename the subsystem to 'performance
events' and to propagate this rename through all fields, variables
and API names. (in an ABI compatible fashion)
The word 'event' is also a bit shorter than 'counter' - which makes
it slightly more convenient to write/handle as well.
Thanks goes to Stephane Eranian who first observed this misnomer and
suggested a rename.
User-space tooling and ABI compatibility is not affected - this patch
should be function-invariant. (Also, defconfigs were not touched to
keep the size down.)
This patch has been generated via the following script:
FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')
sed -i \
-e 's/PERF_EVENT_/PERF_RECORD_/g' \
-e 's/PERF_COUNTER/PERF_EVENT/g' \
-e 's/perf_counter/perf_event/g' \
-e 's/nb_counters/nb_events/g' \
-e 's/swcounter/swevent/g' \
-e 's/tpcounter_event/tp_event/g' \
$FILES
for N in $(find . -name perf_counter.[ch]); do
M=$(echo $N | sed 's/perf_counter/perf_event/g')
mv $N $M
done
FILES=$(find . -name perf_event.*)
sed -i \
-e 's/COUNTER_MASK/REG_MASK/g' \
-e 's/COUNTER/EVENT/g' \
-e 's/\<event\>/event_id/g' \
-e 's/counter/event/g' \
-e 's/Counter/Event/g' \
$FILES
... to keep it as correct as possible. This script can also be
used by anyone who has pending perfcounters patches - it converts
a Linux kernel tree over to the new naming. We tried to time this
change to the point in time where the amount of pending patches
is the smallest: the end of the merge window.
Namespace clashes were fixed up in a preparatory patch - and some
stylistic fallout will be fixed up in a subsequent patch.
( NOTE: 'counters' are still the proper terminology when we deal
with hardware registers - and these sed scripts are a bit
over-eager in renaming them. I've undone some of that, but
in case there's something left where 'counter' would be
better than 'event' we can undo that on an individual basis
instead of touching an otherwise nicely automated patch. )
Suggested-by: Stephane Eranian <eranian@google.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Paul Mackerras <paulus@samba.org>
Reviewed-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <linux-arch@vger.kernel.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-21 18:02:48 +08:00
|
|
|
depends on HAVE_PERF_EVENTS
|
2008-12-09 02:38:33 +08:00
|
|
|
select ANON_INODES
|
2010-10-14 14:01:34 +08:00
|
|
|
select IRQ_WORK
|
2008-12-05 03:12:29 +08:00
|
|
|
help
|
2009-09-21 18:20:38 +08:00
|
|
|
Enable kernel support for various performance events provided
|
|
|
|
|
by software and hardware.
|
2008-12-05 03:12:29 +08:00
|
|
|
|
2009-10-31 05:32:25 +08:00
|
|
|
Software events are supported either built-in or via the
|
2009-09-21 18:20:38 +08:00
|
|
|
use of generic tracepoints.
|
2008-12-05 03:12:29 +08:00
|
|
|
|
2009-09-21 18:20:38 +08:00
|
|
|
Most modern CPUs support performance events via performance
|
|
|
|
|
counter registers. These registers count the number of certain
|
2008-12-05 03:12:29 +08:00
|
|
|
types of hw events: such as instructions executed, cachemisses
|
|
|
|
|
suffered, or branches mis-predicted - without slowing down the
|
|
|
|
|
kernel or applications. These registers can also trigger interrupts
|
|
|
|
|
when a threshold number of events have passed - and can thus be
|
|
|
|
|
used to profile the code that runs on that CPU.
|
|
|
|
|
|
2009-09-21 18:20:38 +08:00
|
|
|
The Linux Performance Event subsystem provides an abstraction of
|
2009-10-31 05:32:25 +08:00
|
|
|
these software and hardware event capabilities, available via a
|
2009-09-21 18:20:38 +08:00
|
|
|
system call and used by the "perf" utility in tools/perf/. It
|
2008-12-05 03:12:29 +08:00
|
|
|
provides per task and per CPU counters, and it provides event
|
|
|
|
|
capabilities on top of those.
|
|
|
|
|
|
|
|
|
|
Say Y if unsure.
|
|
|
|
|
|
2009-09-21 22:08:49 +08:00
|
|
|
config DEBUG_PERF_USE_VMALLOC
|
|
|
|
|
default n
|
|
|
|
|
bool "Debug: use vmalloc to back perf mmap() buffers"
|
|
|
|
|
depends on PERF_EVENTS && DEBUG_KERNEL
|
|
|
|
|
select PERF_USE_VMALLOC
|
|
|
|
|
help
|
|
|
|
|
Use vmalloc memory to back perf mmap() buffers.
|
|
|
|
|
|
|
|
|
|
Mostly useful for debugging the vmalloc code on platforms
|
|
|
|
|
that don't require it.
|
|
|
|
|
|
|
|
|
|
Say N if unsure.
|
|
|
|
|
|
2008-12-05 03:12:29 +08:00
|
|
|
endmenu
|
|
|
|
|
|
2006-06-30 16:55:45 +08:00
|
|
|
config VM_EVENT_COUNTERS
|
|
|
|
|
default y
|
2011-01-21 06:44:16 +08:00
|
|
|
bool "Enable VM event counters for /proc/vmstat" if EXPERT
|
2006-06-30 16:55:45 +08:00
|
|
|
help
|
2006-12-22 17:06:10 +08:00
|
|
|
VM event counters are needed for event counts to be shown.
|
|
|
|
|
This option allows the disabling of the VM event counters
|
2011-01-21 06:44:16 +08:00
|
|
|
on EXPERT systems. /proc/vmstat will only show page counts
|
2006-12-22 17:06:10 +08:00
|
|
|
if VM event counters are disabled.
|
2006-06-30 16:55:45 +08:00
|
|
|
|
2008-08-19 16:28:24 +08:00
|
|
|
config PCI_QUIRKS
|
|
|
|
|
default y
|
2011-01-21 06:44:16 +08:00
|
|
|
bool "Enable PCI quirk workarounds" if EXPERT
|
2008-10-22 14:53:25 +08:00
|
|
|
depends on PCI
|
2008-08-19 16:28:24 +08:00
|
|
|
help
|
|
|
|
|
This enables workarounds for various PCI chipset
|
|
|
|
|
bugs/quirks. Disable this only if your target machine is
|
|
|
|
|
unaffected by PCI quirks.
|
|
|
|
|
|
2007-05-09 17:32:44 +08:00
|
|
|
config SLUB_DEBUG
|
|
|
|
|
default y
|
2011-01-21 06:44:16 +08:00
|
|
|
bool "Enable SLUB debugging support" if EXPERT
|
2008-04-30 07:16:06 +08:00
|
|
|
depends on SLUB && SYSFS
|
2007-05-09 17:32:44 +08:00
|
|
|
help
|
|
|
|
|
SLUB has extensive debug support features. Disabling these can
|
|
|
|
|
result in significant savings in code size. This also disables
|
|
|
|
|
SLUB sysfs support. /sys/slab will not exist and there will be
|
|
|
|
|
no support for cache validation etc.
|
|
|
|
|
|
2009-03-11 03:55:46 +08:00
|
|
|
config COMPAT_BRK
|
|
|
|
|
bool "Disable heap randomization"
|
|
|
|
|
default y
|
|
|
|
|
help
|
|
|
|
|
Randomizing heap placement makes heap exploits harder, but it
|
|
|
|
|
also breaks ancient binaries (including anything libc5 based).
|
|
|
|
|
This option changes the bootup default to heap randomization
|
2009-01-26 18:12:25 +08:00
|
|
|
disabled, and can be overridden at runtime by setting
|
2009-03-11 03:55:46 +08:00
|
|
|
/proc/sys/kernel/randomize_va_space to 2.
|
|
|
|
|
|
|
|
|
|
On non-ancient distros (post-2000 ones) N is usually a safe choice.
|
|
|
|
|
|
2007-05-07 05:49:36 +08:00
|
|
|
choice
|
|
|
|
|
prompt "Choose SLAB allocator"
|
2007-07-17 19:03:32 +08:00
|
|
|
default SLUB
|
2007-05-07 05:49:36 +08:00
|
|
|
help
|
|
|
|
|
This option allows to select a slab allocator.
|
|
|
|
|
|
|
|
|
|
config SLAB
|
|
|
|
|
bool "SLAB"
|
|
|
|
|
help
|
|
|
|
|
The regular slab allocator that is established and known to work
|
2007-05-09 17:32:47 +08:00
|
|
|
well in all environments. It organizes cache hot objects in
|
2008-11-06 06:18:19 +08:00
|
|
|
per cpu and per node queues.
|
2007-05-07 05:49:36 +08:00
|
|
|
|
|
|
|
|
config SLUB
|
|
|
|
|
bool "SLUB (Unqueued Allocator)"
|
|
|
|
|
help
|
|
|
|
|
SLUB is a slab allocator that minimizes cache line usage
|
|
|
|
|
instead of managing queues of cached objects (SLAB approach).
|
|
|
|
|
Per cpu caching is realized using slabs of objects instead
|
|
|
|
|
of queues of objects. SLUB can use memory efficiently
|
2008-11-06 06:18:19 +08:00
|
|
|
and has enhanced diagnostics. SLUB is the default choice for
|
|
|
|
|
a slab allocator.
|
2007-05-07 05:49:36 +08:00
|
|
|
|
|
|
|
|
config SLOB
|
2011-01-21 06:44:16 +08:00
|
|
|
depends on EXPERT
|
2007-05-07 05:49:36 +08:00
|
|
|
bool "SLOB (Simple Allocator)"
|
|
|
|
|
help
|
2008-02-05 14:29:38 +08:00
|
|
|
SLOB replaces the stock allocator with a drastically simpler
|
|
|
|
|
allocator. SLOB is generally more space efficient but
|
|
|
|
|
does not perform as well on large systems.
|
2007-05-07 05:49:36 +08:00
|
|
|
|
|
|
|
|
endchoice
|
|
|
|
|
|
2009-12-15 10:00:02 +08:00
|
|
|
config MMAP_ALLOW_UNINITIALIZED
|
|
|
|
|
bool "Allow mmapped anonymous memory to be uninitialized"
|
2011-01-21 06:44:16 +08:00
|
|
|
depends on EXPERT && !MMU
|
2009-12-15 10:00:02 +08:00
|
|
|
default n
|
|
|
|
|
help
|
|
|
|
|
Normally, and according to the Linux spec, anonymous memory obtained
|
|
|
|
|
from mmap() has it's contents cleared before it is passed to
|
|
|
|
|
userspace. Enabling this config option allows you to request that
|
|
|
|
|
mmap() skip that if it is given an MAP_UNINITIALIZED flag, thus
|
|
|
|
|
providing a huge performance boost. If this option is not enabled,
|
|
|
|
|
then the flag will be ignored.
|
|
|
|
|
|
|
|
|
|
This is taken advantage of by uClibc's malloc(), and also by
|
|
|
|
|
ELF-FDPIC binfmt's brk and stack allocator.
|
|
|
|
|
|
|
|
|
|
Because of the obvious security issues, this option should only be
|
|
|
|
|
enabled on embedded devices where you control what is run in
|
|
|
|
|
userspace. Since that isn't generally a problem on no-MMU systems,
|
|
|
|
|
it is normally safe to say Y here.
|
|
|
|
|
|
|
|
|
|
See Documentation/nommu-mmap.txt for more information.
|
|
|
|
|
|
2008-02-03 04:10:36 +08:00
|
|
|
config PROFILING
|
2010-02-26 22:01:23 +08:00
|
|
|
bool "Profiling support"
|
2008-02-03 04:10:36 +08:00
|
|
|
help
|
|
|
|
|
Say Y here to enable the extended profiling support mechanisms used
|
|
|
|
|
by profilers such as OProfile.
|
|
|
|
|
|
2008-07-23 20:15:22 +08:00
|
|
|
#
|
|
|
|
|
# Place an empty function call at each tracepoint site. Can be
|
|
|
|
|
# dynamically changed for a probe function.
|
|
|
|
|
#
|
tracing: Kernel Tracepoints
Implementation of kernel tracepoints. Inspired from the Linux Kernel
Markers. Allows complete typing verification by declaring both tracing
statement inline functions and probe registration/unregistration static
inline functions within the same macro "DEFINE_TRACE". No format string
is required. See the tracepoint Documentation and Samples patches for
usage examples.
Taken from the documentation patch :
"A tracepoint placed in code provides a hook to call a function (probe)
that you can provide at runtime. A tracepoint can be "on" (a probe is
connected to it) or "off" (no probe is attached). When a tracepoint is
"off" it has no effect, except for adding a tiny time penalty (checking
a condition for a branch) and space penalty (adding a few bytes for the
function call at the end of the instrumented function and adds a data
structure in a separate section). When a tracepoint is "on", the
function you provide is called each time the tracepoint is executed, in
the execution context of the caller. When the function provided ends its
execution, it returns to the caller (continuing from the tracepoint
site).
You can put tracepoints at important locations in the code. They are
lightweight hooks that can pass an arbitrary number of parameters, which
prototypes are described in a tracepoint declaration placed in a header
file."
Addition and removal of tracepoints is synchronized by RCU using the
scheduler (and preempt_disable) as guarantees to find a quiescent state
(this is really RCU "classic"). The update side uses rcu_barrier_sched()
with call_rcu_sched() and the read/execute side uses
"preempt_disable()/preempt_enable()".
We make sure the previous array containing probes, which has been
scheduled for deletion by the rcu callback, is indeed freed before we
proceed to the next update. It therefore limits the rate of modification
of a single tracepoint to one update per RCU period. The objective here
is to permit fast batch add/removal of probes on _different_
tracepoints.
Changelog :
- Use #name ":" #proto as string to identify the tracepoint in the
tracepoint table. This will make sure not type mismatch happens due to
connexion of a probe with the wrong type to a tracepoint declared with
the same name in a different header.
- Add tracepoint_entry_free_old.
- Change __TO_TRACE to get rid of the 'i' iterator.
Masami Hiramatsu <mhiramat@redhat.com> :
Tested on x86-64.
Performance impact of a tracepoint : same as markers, except that it
adds about 70 bytes of instructions in an unlikely branch of each
instrumented function (the for loop, the stack setup and the function
call). It currently adds a memory read, a test and a conditional branch
at the instrumentation site (in the hot path). Immediate values will
eventually change this into a load immediate, test and branch, which
removes the memory read which will make the i-cache impact smaller
(changing the memory read for a load immediate removes 3-4 bytes per
site on x86_32 (depending on mov prefixes), or 7-8 bytes on x86_64, it
also saves the d-cache hit).
About the performance impact of tracepoints (which is comparable to
markers), even without immediate values optimizations, tests done by
Hideo Aoki on ia64 show no regression. His test case was using hackbench
on a kernel where scheduler instrumentation (about 5 events in code
scheduler code) was added.
Quoting Hideo Aoki about Markers :
I evaluated overhead of kernel marker using linux-2.6-sched-fixes git
tree, which includes several markers for LTTng, using an ia64 server.
While the immediate trace mark feature isn't implemented on ia64, there
is no major performance regression. So, I think that we don't have any
issues to propose merging marker point patches into Linus's tree from
the viewpoint of performance impact.
I prepared two kernels to evaluate. The first one was compiled without
CONFIG_MARKERS. The second one was enabled CONFIG_MARKERS.
I downloaded the original hackbench from the following URL:
http://devresources.linux-foundation.org/craiger/hackbench/src/hackbench.c
I ran hackbench 5 times in each condition and calculated the average and
difference between the kernels.
The parameter of hackbench: every 50 from 50 to 800
The number of CPUs of the server: 2, 4, and 8
Below is the results. As you can see, major performance regression
wasn't found in any case. Even if number of processes increases,
differences between marker-enabled kernel and marker- disabled kernel
doesn't increase. Moreover, if number of CPUs increases, the differences
doesn't increase either.
Curiously, marker-enabled kernel is better than marker-disabled kernel
in more than half cases, although I guess it comes from the difference
of memory access pattern.
* 2 CPUs
Number of | without | with | diff | diff |
processes | Marker [Sec] | Marker [Sec] | [Sec] | [%] |
--------------------------------------------------------------
50 | 4.811 | 4.872 | +0.061 | +1.27 |
100 | 9.854 | 10.309 | +0.454 | +4.61 |
150 | 15.602 | 15.040 | -0.562 | -3.6 |
200 | 20.489 | 20.380 | -0.109 | -0.53 |
250 | 25.798 | 25.652 | -0.146 | -0.56 |
300 | 31.260 | 30.797 | -0.463 | -1.48 |
350 | 36.121 | 35.770 | -0.351 | -0.97 |
400 | 42.288 | 42.102 | -0.186 | -0.44 |
450 | 47.778 | 47.253 | -0.526 | -1.1 |
500 | 51.953 | 52.278 | +0.325 | +0.63 |
550 | 58.401 | 57.700 | -0.701 | -1.2 |
600 | 63.334 | 63.222 | -0.112 | -0.18 |
650 | 68.816 | 68.511 | -0.306 | -0.44 |
700 | 74.667 | 74.088 | -0.579 | -0.78 |
750 | 78.612 | 79.582 | +0.970 | +1.23 |
800 | 85.431 | 85.263 | -0.168 | -0.2 |
--------------------------------------------------------------
* 4 CPUs
Number of | without | with | diff | diff |
processes | Marker [Sec] | Marker [Sec] | [Sec] | [%] |
--------------------------------------------------------------
50 | 2.586 | 2.584 | -0.003 | -0.1 |
100 | 5.254 | 5.283 | +0.030 | +0.56 |
150 | 8.012 | 8.074 | +0.061 | +0.76 |
200 | 11.172 | 11.000 | -0.172 | -1.54 |
250 | 13.917 | 14.036 | +0.119 | +0.86 |
300 | 16.905 | 16.543 | -0.362 | -2.14 |
350 | 19.901 | 20.036 | +0.135 | +0.68 |
400 | 22.908 | 23.094 | +0.186 | +0.81 |
450 | 26.273 | 26.101 | -0.172 | -0.66 |
500 | 29.554 | 29.092 | -0.461 | -1.56 |
550 | 32.377 | 32.274 | -0.103 | -0.32 |
600 | 35.855 | 35.322 | -0.533 | -1.49 |
650 | 39.192 | 38.388 | -0.804 | -2.05 |
700 | 41.744 | 41.719 | -0.025 | -0.06 |
750 | 45.016 | 44.496 | -0.520 | -1.16 |
800 | 48.212 | 47.603 | -0.609 | -1.26 |
--------------------------------------------------------------
* 8 CPUs
Number of | without | with | diff | diff |
processes | Marker [Sec] | Marker [Sec] | [Sec] | [%] |
--------------------------------------------------------------
50 | 2.094 | 2.072 | -0.022 | -1.07 |
100 | 4.162 | 4.273 | +0.111 | +2.66 |
150 | 6.485 | 6.540 | +0.055 | +0.84 |
200 | 8.556 | 8.478 | -0.078 | -0.91 |
250 | 10.458 | 10.258 | -0.200 | -1.91 |
300 | 12.425 | 12.750 | +0.325 | +2.62 |
350 | 14.807 | 14.839 | +0.032 | +0.22 |
400 | 16.801 | 16.959 | +0.158 | +0.94 |
450 | 19.478 | 19.009 | -0.470 | -2.41 |
500 | 21.296 | 21.504 | +0.208 | +0.98 |
550 | 23.842 | 23.979 | +0.137 | +0.57 |
600 | 26.309 | 26.111 | -0.198 | -0.75 |
650 | 28.705 | 28.446 | -0.259 | -0.9 |
700 | 31.233 | 31.394 | +0.161 | +0.52 |
750 | 34.064 | 33.720 | -0.344 | -1.01 |
800 | 36.320 | 36.114 | -0.206 | -0.57 |
--------------------------------------------------------------
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Acked-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: 'Peter Zijlstra' <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-19 00:16:16 +08:00
|
|
|
config TRACEPOINTS
|
2008-07-23 20:15:22 +08:00
|
|
|
bool
|
tracing: Kernel Tracepoints
Implementation of kernel tracepoints. Inspired from the Linux Kernel
Markers. Allows complete typing verification by declaring both tracing
statement inline functions and probe registration/unregistration static
inline functions within the same macro "DEFINE_TRACE". No format string
is required. See the tracepoint Documentation and Samples patches for
usage examples.
Taken from the documentation patch :
"A tracepoint placed in code provides a hook to call a function (probe)
that you can provide at runtime. A tracepoint can be "on" (a probe is
connected to it) or "off" (no probe is attached). When a tracepoint is
"off" it has no effect, except for adding a tiny time penalty (checking
a condition for a branch) and space penalty (adding a few bytes for the
function call at the end of the instrumented function and adds a data
structure in a separate section). When a tracepoint is "on", the
function you provide is called each time the tracepoint is executed, in
the execution context of the caller. When the function provided ends its
execution, it returns to the caller (continuing from the tracepoint
site).
You can put tracepoints at important locations in the code. They are
lightweight hooks that can pass an arbitrary number of parameters, which
prototypes are described in a tracepoint declaration placed in a header
file."
Addition and removal of tracepoints is synchronized by RCU using the
scheduler (and preempt_disable) as guarantees to find a quiescent state
(this is really RCU "classic"). The update side uses rcu_barrier_sched()
with call_rcu_sched() and the read/execute side uses
"preempt_disable()/preempt_enable()".
We make sure the previous array containing probes, which has been
scheduled for deletion by the rcu callback, is indeed freed before we
proceed to the next update. It therefore limits the rate of modification
of a single tracepoint to one update per RCU period. The objective here
is to permit fast batch add/removal of probes on _different_
tracepoints.
Changelog :
- Use #name ":" #proto as string to identify the tracepoint in the
tracepoint table. This will make sure not type mismatch happens due to
connexion of a probe with the wrong type to a tracepoint declared with
the same name in a different header.
- Add tracepoint_entry_free_old.
- Change __TO_TRACE to get rid of the 'i' iterator.
Masami Hiramatsu <mhiramat@redhat.com> :
Tested on x86-64.
Performance impact of a tracepoint : same as markers, except that it
adds about 70 bytes of instructions in an unlikely branch of each
instrumented function (the for loop, the stack setup and the function
call). It currently adds a memory read, a test and a conditional branch
at the instrumentation site (in the hot path). Immediate values will
eventually change this into a load immediate, test and branch, which
removes the memory read which will make the i-cache impact smaller
(changing the memory read for a load immediate removes 3-4 bytes per
site on x86_32 (depending on mov prefixes), or 7-8 bytes on x86_64, it
also saves the d-cache hit).
About the performance impact of tracepoints (which is comparable to
markers), even without immediate values optimizations, tests done by
Hideo Aoki on ia64 show no regression. His test case was using hackbench
on a kernel where scheduler instrumentation (about 5 events in code
scheduler code) was added.
Quoting Hideo Aoki about Markers :
I evaluated overhead of kernel marker using linux-2.6-sched-fixes git
tree, which includes several markers for LTTng, using an ia64 server.
While the immediate trace mark feature isn't implemented on ia64, there
is no major performance regression. So, I think that we don't have any
issues to propose merging marker point patches into Linus's tree from
the viewpoint of performance impact.
I prepared two kernels to evaluate. The first one was compiled without
CONFIG_MARKERS. The second one was enabled CONFIG_MARKERS.
I downloaded the original hackbench from the following URL:
http://devresources.linux-foundation.org/craiger/hackbench/src/hackbench.c
I ran hackbench 5 times in each condition and calculated the average and
difference between the kernels.
The parameter of hackbench: every 50 from 50 to 800
The number of CPUs of the server: 2, 4, and 8
Below is the results. As you can see, major performance regression
wasn't found in any case. Even if number of processes increases,
differences between marker-enabled kernel and marker- disabled kernel
doesn't increase. Moreover, if number of CPUs increases, the differences
doesn't increase either.
Curiously, marker-enabled kernel is better than marker-disabled kernel
in more than half cases, although I guess it comes from the difference
of memory access pattern.
* 2 CPUs
Number of | without | with | diff | diff |
processes | Marker [Sec] | Marker [Sec] | [Sec] | [%] |
--------------------------------------------------------------
50 | 4.811 | 4.872 | +0.061 | +1.27 |
100 | 9.854 | 10.309 | +0.454 | +4.61 |
150 | 15.602 | 15.040 | -0.562 | -3.6 |
200 | 20.489 | 20.380 | -0.109 | -0.53 |
250 | 25.798 | 25.652 | -0.146 | -0.56 |
300 | 31.260 | 30.797 | -0.463 | -1.48 |
350 | 36.121 | 35.770 | -0.351 | -0.97 |
400 | 42.288 | 42.102 | -0.186 | -0.44 |
450 | 47.778 | 47.253 | -0.526 | -1.1 |
500 | 51.953 | 52.278 | +0.325 | +0.63 |
550 | 58.401 | 57.700 | -0.701 | -1.2 |
600 | 63.334 | 63.222 | -0.112 | -0.18 |
650 | 68.816 | 68.511 | -0.306 | -0.44 |
700 | 74.667 | 74.088 | -0.579 | -0.78 |
750 | 78.612 | 79.582 | +0.970 | +1.23 |
800 | 85.431 | 85.263 | -0.168 | -0.2 |
--------------------------------------------------------------
* 4 CPUs
Number of | without | with | diff | diff |
processes | Marker [Sec] | Marker [Sec] | [Sec] | [%] |
--------------------------------------------------------------
50 | 2.586 | 2.584 | -0.003 | -0.1 |
100 | 5.254 | 5.283 | +0.030 | +0.56 |
150 | 8.012 | 8.074 | +0.061 | +0.76 |
200 | 11.172 | 11.000 | -0.172 | -1.54 |
250 | 13.917 | 14.036 | +0.119 | +0.86 |
300 | 16.905 | 16.543 | -0.362 | -2.14 |
350 | 19.901 | 20.036 | +0.135 | +0.68 |
400 | 22.908 | 23.094 | +0.186 | +0.81 |
450 | 26.273 | 26.101 | -0.172 | -0.66 |
500 | 29.554 | 29.092 | -0.461 | -1.56 |
550 | 32.377 | 32.274 | -0.103 | -0.32 |
600 | 35.855 | 35.322 | -0.533 | -1.49 |
650 | 39.192 | 38.388 | -0.804 | -2.05 |
700 | 41.744 | 41.719 | -0.025 | -0.06 |
750 | 45.016 | 44.496 | -0.520 | -1.16 |
800 | 48.212 | 47.603 | -0.609 | -1.26 |
--------------------------------------------------------------
* 8 CPUs
Number of | without | with | diff | diff |
processes | Marker [Sec] | Marker [Sec] | [Sec] | [%] |
--------------------------------------------------------------
50 | 2.094 | 2.072 | -0.022 | -1.07 |
100 | 4.162 | 4.273 | +0.111 | +2.66 |
150 | 6.485 | 6.540 | +0.055 | +0.84 |
200 | 8.556 | 8.478 | -0.078 | -0.91 |
250 | 10.458 | 10.258 | -0.200 | -1.91 |
300 | 12.425 | 12.750 | +0.325 | +2.62 |
350 | 14.807 | 14.839 | +0.032 | +0.22 |
400 | 16.801 | 16.959 | +0.158 | +0.94 |
450 | 19.478 | 19.009 | -0.470 | -2.41 |
500 | 21.296 | 21.504 | +0.208 | +0.98 |
550 | 23.842 | 23.979 | +0.137 | +0.57 |
600 | 26.309 | 26.111 | -0.198 | -0.75 |
650 | 28.705 | 28.446 | -0.259 | -0.9 |
700 | 31.233 | 31.394 | +0.161 | +0.52 |
750 | 34.064 | 33.720 | -0.344 | -1.01 |
800 | 36.320 | 36.114 | -0.206 | -0.57 |
--------------------------------------------------------------
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Acked-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: 'Peter Zijlstra' <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-19 00:16:16 +08:00
|
|
|
|
2008-02-03 04:10:33 +08:00
|
|
|
source "arch/Kconfig"
|
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
endmenu # General setup
|
|
|
|
|
|
2008-06-29 18:18:46 +08:00
|
|
|
config HAVE_GENERIC_DMA_COHERENT
|
|
|
|
|
bool
|
|
|
|
|
default n
|
|
|
|
|
|
2008-01-03 05:04:48 +08:00
|
|
|
config SLABINFO
|
|
|
|
|
bool
|
|
|
|
|
depends on PROC_FS
|
2008-04-14 23:53:02 +08:00
|
|
|
depends on SLAB || SLUB_DEBUG
|
2008-01-03 05:04:48 +08:00
|
|
|
default y
|
|
|
|
|
|
2006-09-17 03:15:53 +08:00
|
|
|
config RT_MUTEXES
|
|
|
|
|
boolean
|
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
config BASE_SMALL
|
|
|
|
|
int
|
|
|
|
|
default 0 if BASE_FULL
|
|
|
|
|
default 1 if !BASE_FULL
|
|
|
|
|
|
2007-07-16 14:39:29 +08:00
|
|
|
menuconfig MODULES
|
2005-04-17 06:20:36 +08:00
|
|
|
bool "Enable loadable module support"
|
|
|
|
|
help
|
|
|
|
|
Kernel modules are small pieces of compiled code which can
|
|
|
|
|
be inserted in the running kernel, rather than being
|
|
|
|
|
permanently built into the kernel. You use the "modprobe"
|
|
|
|
|
tool to add (and sometimes remove) them. If you say Y here,
|
|
|
|
|
many parts of the kernel can be built as modules (by
|
|
|
|
|
answering M instead of Y where indicated): this is most
|
|
|
|
|
useful for infrequently used options which are not required
|
|
|
|
|
for booting. For more information, see the man pages for
|
|
|
|
|
modprobe, lsmod, modinfo, insmod and rmmod.
|
|
|
|
|
|
|
|
|
|
If you say Y here, you will need to run "make
|
|
|
|
|
modules_install" to put the modules under /lib/modules/
|
|
|
|
|
where modprobe can find them (you may need to be root to do
|
|
|
|
|
this).
|
|
|
|
|
|
|
|
|
|
If unsure, say Y.
|
|
|
|
|
|
2008-08-05 01:31:32 +08:00
|
|
|
if MODULES
|
|
|
|
|
|
2008-05-05 08:04:16 +08:00
|
|
|
config MODULE_FORCE_LOAD
|
|
|
|
|
bool "Forced module loading"
|
|
|
|
|
default n
|
|
|
|
|
help
|
2008-05-09 14:25:28 +08:00
|
|
|
Allow loading of modules without version information (ie. modprobe
|
|
|
|
|
--force). Forced module loading sets the 'F' (forced) taint flag and
|
|
|
|
|
is usually a really bad idea.
|
2008-05-05 08:04:16 +08:00
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
config MODULE_UNLOAD
|
|
|
|
|
bool "Module unloading"
|
|
|
|
|
help
|
|
|
|
|
Without this option you will not be able to unload any
|
|
|
|
|
modules (note that some modules may not be unloadable
|
2008-07-23 08:24:26 +08:00
|
|
|
anyway), which makes your kernel smaller, faster
|
|
|
|
|
and simpler. If unsure, say Y.
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
|
config MODULE_FORCE_UNLOAD
|
|
|
|
|
bool "Forced module unloading"
|
|
|
|
|
depends on MODULE_UNLOAD && EXPERIMENTAL
|
|
|
|
|
help
|
|
|
|
|
This option allows you to force a module to unload, even if the
|
|
|
|
|
kernel believes it is unsafe: the kernel will remove the module
|
|
|
|
|
without waiting for anyone to stop using it (using the -f option to
|
|
|
|
|
rmmod). This is mainly for kernel developers and desperate users.
|
|
|
|
|
If unsure, say N.
|
|
|
|
|
|
|
|
|
|
config MODVERSIONS
|
2005-12-27 06:04:02 +08:00
|
|
|
bool "Module versioning support"
|
2005-04-17 06:20:36 +08:00
|
|
|
help
|
|
|
|
|
Usually, you have to use modules compiled with your kernel.
|
|
|
|
|
Saying Y here makes it sometimes possible to use modules
|
|
|
|
|
compiled for different kernels, by adding enough information
|
|
|
|
|
to the modules to (hopefully) spot any changes which would
|
|
|
|
|
make them incompatible with the kernel you are running. If
|
|
|
|
|
unsure, say N.
|
|
|
|
|
|
|
|
|
|
config MODULE_SRCVERSION_ALL
|
|
|
|
|
bool "Source checksum for all modules"
|
|
|
|
|
help
|
|
|
|
|
Modules which contain a MODULE_VERSION get an extra "srcversion"
|
|
|
|
|
field inserted into their modinfo section, which contains a
|
|
|
|
|
sum of the source files which made it. This helps maintainers
|
|
|
|
|
see exactly which source was used to build a module (since
|
|
|
|
|
others sometimes change the module source without updating
|
|
|
|
|
the version). With this option, such a "srcversion" field
|
|
|
|
|
will be created for all modules. If unsure, say N.
|
|
|
|
|
|
2012-09-26 17:09:40 +08:00
|
|
|
config MODULE_SIG
|
|
|
|
|
bool "Module signature verification"
|
|
|
|
|
depends on MODULES
|
2012-09-26 17:11:03 +08:00
|
|
|
select KEYS
|
|
|
|
|
select CRYPTO
|
|
|
|
|
select ASYMMETRIC_KEY_TYPE
|
|
|
|
|
select ASYMMETRIC_PUBLIC_KEY_SUBTYPE
|
|
|
|
|
select PUBLIC_KEY_ALGO_RSA
|
|
|
|
|
select ASN1
|
|
|
|
|
select OID_REGISTRY
|
|
|
|
|
select X509_CERTIFICATE_PARSER
|
2012-09-26 17:09:40 +08:00
|
|
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help
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Check modules for valid signatures upon load: the signature
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is simply appended to the module. For more information see
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Documentation/module-signing.txt.
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2012-09-26 17:09:50 +08:00
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!!!WARNING!!! If you enable this option, you MUST make sure that the
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module DOES NOT get stripped after being signed. This includes the
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debuginfo strip done by some packagers (such as rpmbuild) and
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inclusion into an initramfs that wants the module size reduced.
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2012-09-26 17:09:40 +08:00
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config MODULE_SIG_FORCE
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bool "Require modules to be validly signed"
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depends on MODULE_SIG
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help
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Reject unsigned modules or signed modules for which we don't have a
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key. Without this, such modules will simply taint the kernel.
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2012-09-26 17:09:50 +08:00
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choice
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prompt "Which hash algorithm should modules be signed with?"
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depends on MODULE_SIG
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help
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This determines which sort of hashing algorithm will be used during
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signature generation. This algorithm _must_ be built into the kernel
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directly so that signature verification can take place. It is not
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possible to load a signed module containing the algorithm to check
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the signature on that module.
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config MODULE_SIG_SHA1
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bool "Sign modules with SHA-1"
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select CRYPTO_SHA1
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config MODULE_SIG_SHA224
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bool "Sign modules with SHA-224"
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select CRYPTO_SHA256
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config MODULE_SIG_SHA256
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bool "Sign modules with SHA-256"
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select CRYPTO_SHA256
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config MODULE_SIG_SHA384
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bool "Sign modules with SHA-384"
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select CRYPTO_SHA512
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config MODULE_SIG_SHA512
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bool "Sign modules with SHA-512"
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select CRYPTO_SHA512
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endchoice
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2008-08-05 01:31:32 +08:00
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endif # MODULES
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2008-12-13 18:49:41 +08:00
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config INIT_ALL_POSSIBLE
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bool
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help
|
2012-03-29 13:08:31 +08:00
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Back when each arch used to define their own cpu_online_mask and
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cpu_possible_mask, some of them chose to initialize cpu_possible_mask
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2008-12-13 18:49:41 +08:00
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with all 1s, and others with all 0s. When they were centralised,
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it was better to provide this option than to break all the archs
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2009-01-26 18:12:25 +08:00
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and have several arch maintainers pursuing me down dark alleys.
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2008-12-13 18:49:41 +08:00
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2005-04-17 06:20:36 +08:00
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config STOP_MACHINE
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bool
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default y
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depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
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help
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|
Need stop_machine() primitive.
|
2005-11-04 15:43:35 +08:00
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source "block/Kconfig"
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2007-10-17 14:27:31 +08:00
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config PREEMPT_NOTIFIERS
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bool
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2008-01-26 04:08:24 +08:00
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2010-01-06 16:47:10 +08:00
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config PADATA
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depends on SMP
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bool
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|
2012-10-05 08:11:27 +08:00
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# Can be selected by architectures with broken toolchains
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|
|
# that get confused by correct const<->read_only section
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# mappings
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config BROKEN_RODATA
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bool
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|
2012-09-22 06:31:13 +08:00
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config ASN1
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tristate
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help
|
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|
Build a simple ASN.1 grammar compiler that produces a bytecode output
|
|
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|
|
that can be interpreted by the ASN.1 stream decoder and used to
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|
|
inform it as to what tags are to be expected in a stream and what
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|
|
functions to call on what tags.
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|
2009-11-09 23:21:34 +08:00
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|
|
source "kernel/Kconfig.locks"
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