The remaining counters in page_state after the zoned VM counter patches
have been applied are all just for show in /proc/vmstat. They have no
essential function for the VM.
We use a simple increment of per cpu variables. In order to avoid the most
severe races we disable preempt. Preempt does not prevent the race between
an increment and an interrupt handler incrementing the same statistics
counter. However, that race is exceedingly rare, we may only loose one
increment or so and there is no requirement (at least not in kernel) that
the vm event counters have to be accurate.
In the non preempt case this results in a simple increment for each
counter. For many architectures this will be reduced by the compiler to a
single instruction. This single instruction is atomic for i386 and x86_64.
And therefore even the rare race condition in an interrupt is avoided for
both architectures in most cases.
The patchset also adds an off switch for embedded systems that allows a
building of linux kernels without these counters.
The implementation of these counters is through inline code that hopefully
results in only a single instruction increment instruction being emitted
(i386, x86_64) or in the increment being hidden though instruction
concurrency (EPIC architectures such as ia64 can get that done).
Benefits:
- VM event counter operations usually reduce to a single inline instruction
on i386 and x86_64.
- No interrupt disable, only preempt disable for the preempt case.
Preempt disable can also be avoided by moving the counter into a spinlock.
- Handling is similar to zoned VM counters.
- Simple and easily extendable.
- Can be omitted to reduce memory use for embedded use.
References:
RFC http://marc.theaimsgroup.com/?l=linux-kernel&m=113512330605497&w=2
RFC http://marc.theaimsgroup.com/?l=linux-kernel&m=114988082814934&w=2
local_t http://marc.theaimsgroup.com/?l=linux-kernel&m=114991748606690&w=2
V2 http://marc.theaimsgroup.com/?t=115014808400007&r=1&w=2
V3 http://marc.theaimsgroup.com/?l=linux-kernel&m=115024767022346&w=2
V4 http://marc.theaimsgroup.com/?l=linux-kernel&m=115047968808926&w=2
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Core functions for the rt-mutex subsystem.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild: (40 commits)
kbuild: trivial fixes in Makefile
kbuild: adding symbols in Kconfig and defconfig to TAGS
kbuild: replace abort() with exit(1)
kbuild: support for %.symtypes files
kbuild: fix silentoldconfig recursion
kbuild: add option for stripping modules while installing them
kbuild: kill some false positives from modpost
kbuild: export-symbol usage report generator
kbuild: fix make -rR breakage
kbuild: append -dirty for updated but uncommited changes
kbuild: append git revision for all untagged commits
kbuild: fix module.symvers parsing in modpost
kbuild: ignore make's built-in rules & variables
kbuild: bugfix with initramfs
kbuild: modpost build fix
kbuild: check license compatibility when building modules
kbuild: export-type enhancement to modpost.c
kbuild: add dependency on kernel.release to the package targets
kbuild: `make kernelrelease' speedup
kconfig: KCONFIG_OVERWRITECONFIG
...
Architecture specific configs like this have no business at all
in init/Kconfig. This prevents it from being set on x86-64
Pointed out by H.Peter Anvin
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make makes sysctl non-optional unless EMBEDDED is set. There are a number
of interfaces exposed via sysctl, enough that it has to be considered core
kernel functionality at this point.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
In this implementation, audit registers inotify watches on the parent
directories of paths specified in audit rules. When audit's inotify
event handler is called, it updates any affected rules based on the
filesystem event. If the parent directory is renamed, removed, or its
filesystem is unmounted, audit removes all rules referencing that
inotify watch.
To keep things simple, this implementation limits location-based
auditing to the directory entries in an existing directory. Given
a path-based rule for /foo/bar/passwd, the following table applies:
passwd modified -- audit event logged
passwd replaced -- audit event logged, rules list updated
bar renamed -- rule removed
foo renamed -- untracked, meaning that the rule now applies to
the new location
Audit users typically want to have many rules referencing filesystem
objects, which can significantly impact filtering performance. This
patch also adds an inode-number-based rule hash to mitigate this
situation.
The patch is relative to the audit git tree:
http://kernel.org/git/?p=linux/kernel/git/viro/audit-current.git;a=summary
and uses the inotify kernel API:
http://lkml.org/lkml/2006/6/1/145
Signed-off-by: Amy Griffis <amy.griffis@hp.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This makes it possible to change two options which were hardcoded sofar.
1. Any symbol can now take the role of CONFIG_MODULES
2. The more useful option is to change the list of default file names,
which kconfig uses to load the base configuration if .config isn't
available.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Move the DOUBLEFAULT option from the top-level menu to the EMBEDDED menu.
Only applicable to X86_32.
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* master.kernel.org:/pub/scm/linux/kernel/git/sam/kbuild: (46 commits)
kbuild: remove obsoleted scripts/reference_* files
kbuild: fix make help & make *pkg
kconfig: fix time ordering of writes to .kconfig.d and include/linux/autoconf.h
Kconfig: remove the CONFIG_CC_ALIGN_* options
kbuild: add -fverbose-asm to i386 Makefile
kbuild: clean-up genksyms
kbuild: Lindent genksyms.c
kbuild: fix genksyms build error
kbuild: in makefile.txt note that Makefile is preferred name for kbuild files
kbuild: replace PHONY with FORCE
kbuild: Fix bug in crc symbol generating of kernel and modules
kbuild: change kbuild to not rely on incorrect GNU make behavior
kbuild: when warning symbols exported twice now tell user this is the problem
kbuild: fix make dir/file.xx when asm symlink is missing
kbuild: in the section mismatch check try harder to find symbols
kbuild: fix section mismatch check for unwind on IA64
kbuild: kill false positives from section mismatch warnings for powerpc
kbuild: kill trailing whitespace in modpost & friends
kbuild: small update of allnoconfig description
kbuild: make namespace.pl CROSS_COMPILE happy
...
Trivial conflict in arch/ppc/boot/Makefile manually fixed up
MODULE_PARM was actually breaking: recent gcc version optimize them out as
unused. It's time to replace the last users, which are generally in the
most unloved drivers anyway.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I don't see any use case for the CONFIG_CC_ALIGN_* options:
- they are only available if EMBEDDED
- people using EMBEDDED will most likely also enable
CC_OPTIMIZE_FOR_SIZE
- the default for -Os is to disable alignment
In case someone is doing performance comparisons and discovers that the
default settings gcc chooses aren't good, the only sane thing is to discuss
whether it makes sense to change this, not through offering options to change
this locally.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Make SELinux depend on AUDIT as it requires the basic audit support to log
permission denials at all. Note that AUDITSYSCALL remains optional for
SELinux, although it can be useful in providing further information upon
denials.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Do not allow people to create configurations with CONFIG_BROKEN=y.
The sole reason for CONFIG_BROKEN=y would be if you are working on fixing a
broken driver, but in this case editing the Kconfig file is trivial.
Never ever should a user enable CONFIG_BROKEN.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Build kernel/intermodule.c only when required.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It has no business being elsewhere and x86-64 doesn't need/want it.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It seems the "make UID16 support optional" patch was checked when it
edited the -tiny tree some time ago, but it wasn't checked whether it
still matches the current situation when it was submitted for inclusion
in -mm. This patch fixes the following bugs:
- ARCH_S390X does no longer exist, nowadays this has to be expressed
through (S390 && 64BIT)
- in five architecture specific Kconfig files the UID16 options
weren't removed
Additionally, it changes the fragile negative dependencies of UID16 to
positive dependencies (new architectures are more likely to not require
UID16 support).
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This adds an option to remove vm86 support under CONFIG_EMBEDDED. Saves
about 5k.
This version eliminates most of the #ifdefs of the previous version and
instead uses function stubs in vm86.h. Also, release_vm86_irqs is moved
from asm-i386/irq.h to a more appropriate home in vm86.h so that the stubs
can live together.
$ size vmlinux-baseline vmlinux-novm86
text data bss dec hex filename
2920821 523232 190652 3634705 377611 vmlinux-baseline
2916268 523100 190492 3629860 376324 vmlinux-novm86
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Configurable 16-bit UID and friends support
This allows turning off the legacy 16 bit UID interfaces on embedded platforms.
text data bss dec hex filename
3330172 529036 190556 4049764 3dcb64 vmlinux-baseline
3328268 529040 190556 4047864 3dc3f8 vmlinux
From: Adrian Bunk <bunk@stusta.de>
UID16 was accidentially disabled for !EMBEDDED.
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This adds configurable support for doublefault reporting on x86
add/remove: 0/3 grow/shrink: 0/1 up/down: 0/-13048 (-13048)
function old new delta
cpu_init 846 786 -60
doublefault_fn 188 - -188
doublefault_stack 4096 - -4096
doublefault_tss 8704 - -8704
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Sanitize some s390 Kconfig options. We have ARCH_S390, ARCH_S390X,
ARCH_S390_31, 64BIT, S390_SUPPORT and COMPAT. Replace these 6 options by
S390, 64BIT and COMPAT.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The attached patch makes the SYSV IPC shared memory facilities use the new
ramfs facilities on a no-MMU kernel.
The following changes are made:
(1) There are now shmem_mmap() and shmem_get_unmapped_area() functions to
allow the IPC SHM facilities to commune with the tiny-shmem and shmem
code.
(2) ramfs files now need resizing using do_truncate() rather than by modifying
the inode size directly (see shmem_file_setup()). This causes ramfs to
attempt to bind a block of pages of sufficient size to the inode.
(3) CONFIG_SYSVIPC is no longer contingent on CONFIG_MMU.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
With modules, dynamic /dev, and uevents, people really want
CONFIG_HOTPLUG to be enabled in their kernels. If not, they can still
disable it, but it is discouraged.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
It makes zero sense to have hotplug, but not the netlink
events enabled today. Remove this option and merge the
kobject_uevent.h header into the kobject.h header file.
Signed-off-by: Kay Sievers <kay.sievers@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
It was a stupid workaround for the "static inline" vs.
"extern inline" issues of long ago, and it is what causes
schedule() to be inlined like crazy into kernel/sched.c
when -Os is specified.
MIPS and S390 should probably do the same.
Now CC_OPTIMIZE_FOR_SIZE can be safely used on sparc64
once more.
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
Let's put my money where my mouth is. Smaller code is almost always
faster, if only because a single I$ miss ends up leaving a lot of cycles
to make up for. And system software - kernels in particular - are known
for taking more cache misses than most other kinds.
On my random config, this made the kernel about 10% smaller, and lmbench
seems to say that it's pretty uniformly faster too. Your milage may vary.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
KOBJECT_UEVENT=n seems to be a common pitfall for udev users in 2.6.14 .
-mm already contains a bigger patch removing this option that is IMHO
too big for being applied now to 2.6.15-rc.
This patch simply allows KOBJECT_UEVENT=n only if EMBEDDED.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
drivers/block/ is right now a mix of core and driver parts. Lets move
the core parts to a new top level directory. Al will move the fs/
related block parts to block/ next.
Signed-off-by: Jens Axboe <axboe@suse.de>
Try to make the INIT_ENV_ARG_LIMIT help text more readable and
understandable.
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If CONFIG_AUTO_LOCALVERSION is set, the user is using a git-based tree, and the
current HEAD is not referred to by any tags in .git/refs/tags/, append -g and
the first 8 characters of the commit to the version string. This makes it
easier to use git-bisect, and/or to do a daily build, without trampling on your
older, working builds, or accidentally setting up conflicting sets of modules.
Signed-off-by: Ryan Anderson <ryan@michonline.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Move initramfs options from Device Drivers | Block Drivers to General Setup
This is a more natural place for this option.
Furthermore separate out intramfs options to usr/Kconfig
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Add kerneldoc to kernel/cpuset.c
Fix cpuset typos in init/Kconfig
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Acked-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Actually, the real support was added by some earlier patches. Now we simply
re-enable the config. option. I've actually tested it and it works well.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Audit now actually requires netlink. So make it depend on CONFIG_NET,
and remove the inline dependencies on CONFIG_NET.
Signed-off-by: Chris Wright <chrisw@osdl.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
