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This patch contains the shim module (XP) which interfaces between the
communication module (XPC) and the functional support modules (like XPNET).
Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
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Add some needed externs currently not defined.
Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
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Define some additional SHub1 and SHub2 register symbols.
Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
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Another step in the effort to eliminate the SN pda structure.
This patch moves the cnodeid_to_nasid_table field out of the pda,
making it a standalone per-cpu data item, and exports it so it can
be accessed by kernel modules.
Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
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Here is a patch to enable the SGI tiocx bus driver to distingush between
FPGA-attached h/w and non-FPGA-attached h/w.
Signed-off-by: Bruce Losure <blosure@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
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This patch cleans up include/asm/sn/shubio.h by removing a ton of
whitespaces and running it through Lindent, reducing it's size by almost
30KB. No actual content has been changed.
Signed-off-by: Jes Sorensen <jes@wildopensource.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
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This patch makes Jes' patch (which also contains the removal of fetchop.h) a
bit smaller, and removes two other unused files at the same time, sndrv.h and
sn_fru.h.
Signed-off-by: Jesse Barnes <jbarnes@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
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The clock spreading disable/enable code was called to late/early during
the suspend/resume code on some laptops and would trigger a
might_sleep() warning due to the down() call in the low level i2c code.
This fixes it by calling those functions earlier/later when interrupts
are still enabled.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Another large rollup of various patches from Adrian which make things static
where they were needlessly exported.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Some KernelDoc descriptions are updated to match the current code.
No code changes.
Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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I have recompiled Linux kernel 2.6.11.5 documentation for me and our
university students again. The documentation could be extended for more
sources which are equipped by structured comments for recent 2.6 kernels. I
have tried to proceed with that task. I have done that more times from 2.6.0
time and it gets boring to do same changes again and again. Linux kernel
compiles after changes for i386 and ARM targets. I have added references to
some more files into kernel-api book, I have added some section names as well.
So please, check that changes do not break something and that categories are
not too much skewed.
I have changed kernel-doc to accept "fastcall" and "asmlinkage" words reserved
by kernel convention. Most of the other changes are modifications in the
comments to make kernel-doc happy, accept some parameters description and do
not bail out on errors. Changed <pid> to @pid in the description, moved some
#ifdef before comments to correct function to comments bindings, etc.
You can see result of the modified documentation build at
http://cmp.felk.cvut.cz/~pisa/linux/lkdb-2.6.11.tar.gz
Some more sources are ready to be included into kernel-doc generated
documentation. Sources has been added into kernel-api for now. Some more
section names added and probably some more chaos introduced as result of quick
cleanup work.
Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>
Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Attached is a patch against 2.6.11.7 which tidies up the tdfxfb framebuffer
size detection code a little and fixes the broken support for Voodoo4/5
cards. (I haven't tested this on a Voodoo5, however, because I don't have
the hardware).
Signed-off-by: Richard Drummond <evilrich@rcdrummond.net>
Cc: <linux-fbdev-devel@lists.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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This patch removes some completely unused code.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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This patch adds to the fbdev interface a set_cmap callback that allow the
driver to "batch" palette changes. This is useful for drivers like
radeonfb which might require lenghtly workarounds on palette accesses, thus
allowing to factor out those workarounds efficiently.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Since we only access reiserfs_key ->u.k_offset_v2 guts in four helper
functions, we are free to sanitize those, as long as
- layout of the structure is unchanged (it's on-disk object)
- behaviour of these helpers is same as before.
Patch kills the mess with endianness-dependent bitfields and replaces them
with a single __le64. Helpers are switched to straightforward shift/and/or.
Benefits:
- exact same definitions for little- and big-endian architectures; no ifdefs
in sight.
- generate the same code on little-endian and improved on big-endian.
- doesn't rely on lousy bitfields handling in gcc codegenerator.
- happens to be standard C (unsigned long long is not a valid type for a
bitfield; it's a gccism and not well-implemented one, at that).
Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Cc: <reiserfs-dev@namesys.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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comp_short_keys() massaged into sane form, which kills the last place where
pointer to in_core_key (or any object containing such) would be cast to or
from something else. At that point we are free to change layout of
in_core_key - nothing depends on it anymore.
So we drop the mess with union in there and simply use (unconditional) __u64
k_offset and __u8 k_type instead; places using in_core_key switched to those.
That gives _far_ better code than current mess - on all platforms.
Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Cc: <reiserfs-dev@namesys.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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fixes for a couple of bugs exposed by the above: le32_to_cpu() used on 16bit
value and missing conversion in comparison of host- and little-endian values.
Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Cc: <reiserfs-dev@namesys.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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little-endian objects annotated as such; again, obviously no changes of
resulting code, we only replace __u16 with __le16, etc. in relevant places.
Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Cc: <reiserfs-dev@namesys.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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struct reiserfs_key cloned; (currently) identical struct in_core_key added.
Places that expect host-endian data in reiserfs_key switched to in_core_key.
Basically, we get annotation of reiserfs_key users and keep the resulting tree
obviously equivalent to original.
Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Cc: <reiserfs-dev@namesys.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Bump autofs4 version so we know what's going on.
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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This patch adds a new function valid_signal() that tests if its argument is
a valid signal number.
The reasons for adding this new function are:
- some code currently testing _NSIG directly has off-by-one errors.
Using this function instead avoids such errors.
- some code currently tests unsigned signal numbers for <0 which is
pointless and generates warnings when building with gcc -W. Using this
function instead avoids such warnings.
I considered various places to add this function but eventually settled on
include/linux/signal.h as the most logical place for it. If there's some
reason this is a bad choice then please let me know (hints as to a better
location are then welcome of course).
Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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The variable attributes "packed" and "align" when used with struct, should
have the following order:
struct ... {...} __attribute__((packed)) var;
This patch fixes few instances where the variable and attributes are placed
the other way around and had no effect.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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There were still a few comments left refering to verify_area, and two
functions, verify_area_skas & verify_area_tt that just wrap corresponding
access_ok_skas & access_ok_tt functions, just like verify_area does for
access_ok - deprecate those.
There was also a few places that still used verify_area in commented-out
code, fix those up to use access_ok.
After applying this one there should not be anything left but finally
removing verify_area completely, which will happen after a kernel release
or two.
Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Discussing with Matthew Wilcox some of his outstanding patches lead me to
this patch (among others).
The preamble in struct sigevent can be expressed independently of the
architecture.
Also use __ARCH_SI_PREAMBLE_SIZE on ia64.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Add EOWNERDEAD and ENOTRECOVERABLE to all architectures. This is to
support the upcoming patches for robust mutexes.
We normally don't reserve parts of the name/number space for external
patches, but robust mutexes are sufficiently popular and important to
justify it in this case.
Signed-off-by: Joe Korty <joe.korty@ccur.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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The synchronize_kernel() primitive is used for quite a few different purposes:
waiting for RCU readers, waiting for NMIs, waiting for interrupts, and so on.
This makes RCU code harder to read, since synchronize_kernel() might or might
not have matching rcu_read_lock()s. This patch creates a new
synchronize_rcu() that is to be used for RCU readers and a new
synchronize_sched() that is used for the rest. These two new primitives
currently have the same implementation, but this is might well change with
additional real-time support. Both new primitives are GPL-only, the old
primitive is deprecated.
Signed-off-by: Paul E. McKenney <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Add a deprecated_for_modules macro that allows symbols to be deprecated only
when used by modules, as suggested by Andrew Morton some months back.
Signed-off-by: Paul E. McKenney <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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The attached patch moves the IRQ-related SA_xxx flags (namely, SA_PROBE,
SA_SAMPLE_RANDOM and SA_SHIRQ) from all the arch-specific headers to
linux/signal.h. This looks like a left-over after the irq-handling code
was consolidated. The code was moved to kernel/irq/*, but the flags are
still left per-arch.
Right now, adding a new IRQ flag to the arch-specific header, like this
patch does:
http://cvs.sourceforge.net/viewcvs.py/*checkout*/alsa/alsa-driver/utils/patches/pcsp-kernel-2.6.10-03.diff?rev=1.1
no longer works, it breaks the compilation for all other arches, unless you
add that flag to all the other arch-specific headers too. So I think such
a clean-up makes sense.
Signed-off-by: Stas Sergeev <stsp@aknet.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Arrange for all kernel printks to be no-ops. Only available if
CONFIG_EMBEDDED.
This patch saves about 375k on my laptop config and nearly 100k on minimal
configs.
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Remove PAGE_BUG - repalce it with BUG and BUG_ON.
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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This patch eliminates all kernel BUGs, trims about 35k off the typical
kernel, and makes the system slightly faster.
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Add a pair of rlimits for allowing non-root tasks to raise nice and rt
priorities. Defaults to traditional behavior. Originally written by
Chris Wright.
The patch implements a simple rlimit ceiling for the RT (and nice) priorities
a task can set. The rlimit defaults to 0, meaning no change in behavior by
default. A value of 50 means RT priority levels 1-50 are allowed. A value of
100 means all 99 privilege levels from 1 to 99 are allowed. CAP_SYS_NICE is
blanket permission.
(akpm: see http://www.uwsg.iu.edu/hypermail/linux/kernel/0503.1/1921.html for
tips on integrating this with PAM).
Signed-off-by: Matt Mackall <mpm@selenic.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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The ioctl32_conversion routines will be deprecated: Remove them from dasd_cmb
and handle the three cmb ioctls like all other dasd ioctls.
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>
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The current limitation of 16 characters of the debug feature names turned out
to be insufficient. Increase it to 64 characters.
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>
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Provide an easy way to define a non-zero storage key at compile time. This is
useful for debugging purposes.
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>
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Add some commentary about UML internals, for a strange trick.
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>
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GCC 2.95 uses __va_copy instead of va_copy. Handle it inside compiler.h
instead of in a casual file, and avoid the risk that this breaks with a newer
compiler (which it could do).
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>
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Cleanup: make an inline of this empty proc.
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>
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We want to make possible, for the user, to enable the i586 AES implementation.
This requires a restructure.
- Add a CONFIG_UML_X86 to notify that we are building a UML for i386.
- Rename CONFIG_64_BIT to CONFIG_64BIT as is used for all other archs
- Tell crypto/Kconfig that UML_X86 is as good as X86
- Tell it that it must exclude not X86_64 but 64BIT, which will give the
same results.
- Tell kbuild to descend down into arch/i386/crypto/ to build what's needed.
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>
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Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Prevent the kernel from oopsing during the extable sorting, as it can do
now, because the extable is in the readonly section of the binary.
Jeff says: The exception table turned RO in 2.6.11-rc3-mm1 for some reason.
Moving it causes it to land in the writable data section of the binary.
Paolo says: This patch fixes a oops on startup, which can be easily
triggered by compiling with CONFIG_MODE_TT disabled, and STATIC_LINK either
disabled or enabled. The resulting kernel will always Oops on startup,
after printing this simple output:
I've verified, by binary search on the BitKeeper repository (synced up as
of 2.6.12-rc2), starting from the range 2.6.11-2.6.12-rc1, that this bug
shows up on BitKeeper revisions in the range [@1.1994.11.168,+inf), i.e.
starting from this:
[PATCH] lib/sort: Replace insertion sort in exception tables
Since UML does not use the exception table, it's likely that insertion sort
didn't happen to write anything on the table.
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>
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The specifications that talk about E820 map doesn't have an upper limit on
the number of e820 entries. But, today's kernel has a hard limit of 32.
With increase in memory size, we are seeing the number of E820 entries
reaching close to 32. Patch below bumps the number upto 128.
The patch changes the location of EDDBUF in zero-page (as it comes after E820).
As, EDDBUF is not used by boot loaders, this patch should not have any effect
on bootloader-setup code interface.
Patch covers both i386 and x86-64.
Tested on:
* grub booting bzImage
* lilo booting bzImage with EDID info enabled
* pxeboot of bzImage
Side-effect:
bss increases by ~ 2K and init.data increases by ~7.5K
on all systems, due to increase in size of static arrays.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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This patch adds the Intel ICH7DH and ICH7-M DH DID's to the irq.c and
pci_ids.h files.
Signed-off-by: Jason Gaston <Jason.d.gaston@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Currently the i386 HPET code assumes the entire HPET implementation from
the spec is present. This breaks on boxes that do not implement the
optional legacy timer replacement functionality portion of the spec.
This patch, which is very similar to my x86-64 patch for the same issue,
fixes the problem allowing i386 systems that cannot use the HPET for the
timer interrupt and RTC to still use the HPET as a time source. I've
tested this patch on a system systems without HPET, with HPET but without
legacy timer replacement, as well as HPET with legacy timer replacement.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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The recent support for K8 multicore was misported from x86-64 to i386, due
to an unnecessary inconsistency between the CPUID code. Sure, there is are
no x86-64 VIA chips yet, but it should happen eventually.
This patch fixes the i386 bug as well as makes x86-64 match i386 in the
handing of the CPUID array.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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This patch by Jaya Kumar introduces a generic infrastructure to deal with
x86 chipsets with nonstandard reset sequences, and adds support for the
Geode gx1/cs5530a chipset.
Signed-off-by: Jaya Kumar <jayalk@intworks.biz>
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>
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A bug against an xSeries system showed up recently noting that the
check_nmi_watchdog() test was failing.
I have been investigating it and discovered in both i386 and x86_64 the
recent change to the routine to use the cpu_callin_map has uncovered a
problem. Prior to that change, on an SMP box, the test was trivally
passing because all cpu's were found to not yet be online, but now with the
callin_map they are discovered, it goes on to test the counter and they
have not yet begun to increment, so it announces a CPU is stuck and bails
out.
On all the systems I have access to test, the announcement of failure is
also bougs... by the time you can login and check /proc/interrupts, the
NMI count is happily incrementing on all CPUs. Its just that the test is
being done too early.
I have tried moving the call to the test around a bit, and it was always
too early. I finally hit on this proposed solution, it delays the routine
via a late_initcall(), seems like the right solution to me.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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The new i386/x86_64 assemblers no longer accept instructions for moving
between a segment register and a 32bit memory location, i.e.,
movl (%eax),%ds
movl %ds,(%eax)
To generate instructions for moving between a segment register and a
16bit memory location without the 16bit operand size prefix, 0x66,
mov (%eax),%ds
mov %ds,(%eax)
should be used. It will work with both new and old assemblers. The
assembler starting from 2.16.90.0.1 will also support
movw (%eax),%ds
movw %ds,(%eax)
without the 0x66 prefix. I am enclosing patches for 2.4 and 2.6 kernels
here. The resulting kernel binaries should be unchanged as before, with
old and new assemblers, if gcc never generates memory access for
unsigned gsindex;
asm volatile("movl %%gs,%0" : "=g" (gsindex));
If gcc does generate memory access for the code above, the upper bits
in gsindex are undefined and the new assembler doesn't allow it.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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This patch shortens non-constant memcpy() by two bytes and fixes spurious
out-of-line constant memcpy().
# size vmlinux.org vmlinux
text data bss dec hex filename
3954591 1553426 236544 5744561 57a7b1 vmlinux.org
3952615 1553426 236544 5742585 579ff9 vmlinux
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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On our raw spinlocks, we currently have an attempt at the lock, and if we do
not get it we enter a spin loop. This spinloop will likely continue for
awhile, and we pridict likely.
Shouldn't we predict that we will get out of the loop so our next instructions
are already prefetched. Even when we miss because the lock is still held, it
won't matter since we are waiting anyways.
I did a couple quick benchmarks, but the results are inconclusive.
16-way 690 running specjbb with original code
# ./specjbb 3000 16 1 1 19 30 120
...
Valid run, Score is 59282
16-way 690 running specjbb with unlikely code
# ./specjbb 3000 16 1 1 19 30 120
...
Valid run, Score is 59541
I saw a smaller increase on a JS20 (~1.6%)
JS20 specjbb w/ original code
# ./specjbb 400 2 1 1 19 30 120
...
Valid run, Score is 20460
JS20 specjbb w/ unlikely code
# ./specjbb 400 2 1 1 19 30 120
...
Valid run, Score is 20803
Anton said:
Mispredicting the spinlock busy loop also means we slow down the rate at which
we do the loads which can be good for heavily contended locks.
Note: There are some gcc issues with our default build and branch prediction,
but a CONFIG_POWER4_ONLY build should emit them correctly. I'm working with
Alan Modra on it now.
Signed-off-by: Jake Moilanen <moilanen@austin.ibm.com>
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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