Commit graph

57 commits

Author SHA1 Message Date
Tejun Heo
0415b00d17 percpu: Always align percpu output section to PAGE_SIZE
Percpu allocator honors alignment request upto PAGE_SIZE and both the
percpu addresses in the percpu address space and the translated kernel
addresses should be aligned accordingly.  The calculation of the
former depends on the alignment of percpu output section in the kernel
image.

The linker script macros PERCPU_VADDR() and PERCPU() are used to
define this output section and the latter takes @align parameter.
Several architectures are using @align smaller than PAGE_SIZE breaking
percpu memory alignment.

This patch removes @align parameter from PERCPU(), renames it to
PERCPU_SECTION() and makes it always align to PAGE_SIZE.  While at it,
add PCPU_SETUP_BUG_ON() checks such that alignment problems are
reliably detected and remove percpu alignment comment recently added
in workqueue.c as the condition would trigger BUG way before reaching
there.

For um, this patch raises the alignment of percpu area.  As the area
is in .init, there shouldn't be any noticeable difference.

This problem was discovered by David Howells while debugging boot
failure on mn10300.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Cc: uclinux-dist-devel@blackfin.uclinux.org
Cc: David Howells <dhowells@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: user-mode-linux-devel@lists.sourceforge.net
2011-03-24 18:50:09 +01:00
Linus Torvalds
16d8775700 Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (91 commits)
  ARM: 6806/1: irq: introduce entry and exit functions for chained handlers
  ARM: 6781/1: Thumb-2: Work around buggy Thumb-2 short branch relocations in gas
  ARM: 6747/1: P2V: Thumb2 support
  ARM: 6798/1: aout-core: zero thread debug registers in a.out core dump
  ARM: 6796/1: Footbridge: Fix I/O mappings for NOMMU mode
  ARM: 6784/1: errata: no automatic Store Buffer drain on Cortex-A9
  ARM: 6772/1: errata: possible fault MMU translations following an ASID switch
  ARM: 6776/1: mach-ux500: activate fix for errata 753970
  ARM: 6794/1: SPEAr: Append UL to device address macros.
  ARM: 6793/1: SPEAr: Remove unused *_SIZE macros from spear*.h files
  ARM: 6792/1: SPEAr: Replace SIZE macro's with SZ_4K macros
  ARM: 6791/1: SPEAr3xx: Declare device structures after shirq code
  ARM: 6790/1: SPEAr: Clock Framework: Rename usbd clock and align apb_clk entry
  ARM: 6789/1: SPEAr3xx: Rename sdio to sdhci
  ARM: 6788/1: SPEAr: Include mach/hardware.h instead of mach/spear.h
  ARM: 6787/1: SPEAr: Reorder #includes in .h & .c files.
  ARM: 6681/1: SPEAr: add debugfs support to clk API
  ARM: 6703/1: SPEAr: update clk API support
  ARM: 6679/1: SPEAr: make clk API functions more generic
  ARM: 6737/1: SPEAr: formalized timer support
  ...
2011-03-16 19:03:06 -07:00
Russell King
05e3475451 Merge branch 'p2v' into devel
Conflicts:
	arch/arm/kernel/module.c
	arch/arm/mach-s5pv210/sleep.S
2011-03-16 23:35:27 +00:00
Linus Torvalds
79d8a8f736 Merge branch 'for-2.6.39' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
* 'for-2.6.39' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu, x86: Add arch-specific this_cpu_cmpxchg_double() support
  percpu: Generic support for this_cpu_cmpxchg_double()
  alpha: use L1_CACHE_BYTES for cacheline size in the linker script
  percpu: align percpu readmostly subsection to cacheline

Fix up trivial conflict in arch/x86/kernel/vmlinux.lds.S due to the
percpu alignment having changed ("x86: Reduce back the alignment of the
per-CPU data section")
2011-03-16 08:22:41 -07:00
Russell King
a9ad21fed0 ARM: Keep exit text/data around for SMP_ON_UP
When SMP_ON_UP is used and the spinlocks are inlined, we end up with
inline spinlocks in the exit code, with references from the SMP
alternatives section to the exit sections.  This causes link time
errors.  Avoid this by placing the exit sections in the init-discarded
region.

Cc: <stable@kernel.org>
Tested-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-21 19:29:27 +00:00
Pawel Moll
dc810efb0c ARM: 6740/1: Place correctly notes section in the linker script
Commit 18991197b4 added --build-id
linker option when toolchain supports it. ARM one does, but for some
reason places the section at 0 when linker script doesn't mention it
explicitly.

The 1e621a8e37 worked around the problem
removing this section from binary image with explicit objcopy options,
but it still exists in vmlinux, confusing tools like debuggers and perf.

This problem was discussed here:
http://lists.infradead.org/pipermail/linux-arm-kernel/2010-May/015994.html
http://lists.infradead.org/pipermail/linux-arm-kernel/2010-May/015994.html
but the proposed changes to the linker script were substantial.

This patch simply places NOTES (36 bytes long, at least when compiled
with CodeSourcery toolchain) between data and bss, which seem to be
the right place (and suggested by the sample linker script in
include/asm-generic/vmlinux.lds.h).

It is enough to place it correctly in vmlinux (so debuggers are happy):

Section Headers:
  [11] .data             PROGBITS        c07ce000 7ce000 020fc0 00  WA  0   0 32
  [12] .notes            NOTE            c07eefc0 7eefc0 000024 00  AX  0   0  4
  [13] .bss              NOBITS          c07ef000 7eefe4 01e628 00  WA  0   0 32
Program Headers:
  LOAD           0x008000 0xc0008000 0xc0008000 0x7e6fe4 0x805628 RWE 0x8000
  NOTE           0x7eefc0 0xc07eefc0 0xc07eefc0 0x00024 0x00024 R E 0x4
Section to Segment mapping:
  Segment Sections...
   00     <...> .data .notes .bss
   01     .notes

and to get it exposed as /sys/kernel/notes used by perf tools.

Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-21 19:29:25 +00:00
Russell King
dc21af99fa ARM: P2V: introduce phys_to_virt/virt_to_phys runtime patching
This idea came from Nicolas, Eric Miao produced an initial version,
which was then rewritten into this.

Patch the physical to virtual translations at runtime.  As we modify
the code, this makes it incompatible with XIP kernels, but allows us
to achieve this with minimal loss of performance.

As many translations are of the form:

	physical = virtual + (PHYS_OFFSET - PAGE_OFFSET)
	virtual = physical - (PHYS_OFFSET - PAGE_OFFSET)

we generate an 'add' instruction for __virt_to_phys(), and a 'sub'
instruction for __phys_to_virt().  We calculate at run time (PHYS_OFFSET
- PAGE_OFFSET) by comparing the address prior to MMU initialization with
where it should be once the MMU has been initialized, and place this
constant into the above add/sub instructions.

Once we have (PHYS_OFFSET - PAGE_OFFSET), we can calculate the real
PHYS_OFFSET as PAGE_OFFSET is a build-time constant, and save this for
the C-mode PHYS_OFFSET variable definition to use.

At present, we are unable to support Realview with Sparsemem enabled
as this uses a complex mapping function, and MSM as this requires a
constant which will not fit in our math instruction.

Add a module version magic string for this feature to prevent
incompatible modules being loaded.

Tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Tested-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-17 23:27:32 +00:00
Tejun Heo
19df0c2fef percpu: align percpu readmostly subsection to cacheline
Currently percpu readmostly subsection may share cachelines with other
percpu subsections which may result in unnecessary cacheline bounce
and performance degradation.

This patch adds @cacheline parameter to PERCPU() and PERCPU_VADDR()
linker macros, makes each arch linker scripts specify its cacheline
size and use it to align percpu subsections.

This is based on Shaohua's x86 only patch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Shaohua Li <shaohua.li@intel.com>
2011-01-25 14:26:50 +01:00
Russell King
4073723acb Merge branch 'misc' into devel
Conflicts:
	arch/arm/Kconfig
	arch/arm/common/Makefile
	arch/arm/kernel/Makefile
	arch/arm/kernel/smp.c
2011-01-06 22:32:52 +00:00
Russell King
daf8741675 ARM: implement support for read-mostly sections
As our SMP implementation uses MESI protocols.  Grouping together data
which is mostly only read together means that we avoid unnecessary
cache line bouncing when this code shares a cache line with other data.

In other words, cache lines associated with read-mostly data are
expected to spend most of their time in shared state.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-05 08:39:36 +00:00
Rabin Vincent
61b5cb1c3b ARM: place C irq handlers in IRQ_ENTRY for ftrace
When FUNCTION_GRAPH_TRACER is enabled, place do_IRQ() and friends in the
IRQ_ENTRY section so that the irq-related features of the function graph
tracer work.

Signed-off-by: Rabin Vincent <rabin@rab.in>
2010-11-19 21:43:26 +05:30
Tony Lindgren
88d927e948 ARM: 6465/1: Fix data abort accessing proc_info from __lookup_processor_type
Commit 5085f3ff45 added better support for
CONFIG_HOTPLUG_CPU by keeping proc_info around. However, depending on
the Kconfig options selected, this can make the booting fail mysteriously
early on.

Turns out a data abort can happen in __lookup_processor in ldmia r5 {r3, r4}.
When it happens the address loaded to r5 is not aligned. Fix the problem by
aligning proc_info.

Reported-by: Anand Gadiyar <gadiyar@ti.com>
Tested-by: Anand Gadiyar <gadiyar@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-10-27 21:40:29 +01:00
Russell King
a0a55682b8 Merge branch 'hotplug' into devel
Conflicts:
	arch/arm/kernel/head-common.S
2010-10-18 22:34:47 +01:00
Russell King
5085f3ff45 ARM: hotplug cpu: Keep processor information, startup code & __lookup_processor_type
When hotplug CPU is enabled, we need to keep the list of supported CPUs,
their setup functions, and __lookup_processor_type in place so that we
can find and initialize secondary CPUs.  Move these into the __CPUINIT
section.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-10-08 10:07:32 +01:00
Russell King
74b0ec0708 ARM: vmlinux.lds: Move unwind tables into _stext.._etext
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-10-08 10:02:25 +01:00
Russell King
f00ec48fad ARM: Allow SMP kernels to boot on UP systems
UP systems do not implement all the instructions that SMP systems have,
so in order to boot a SMP kernel on a UP system, we need to rewrite
parts of the kernel.

Do this using an 'alternatives' scheme, where the kernel code and data
is modified prior to initialization to replace the SMP instructions,
thereby rendering the problematical code ineffectual.  We use the linker
to generate a list of 32-bit word locations and their replacement values,
and run through these replacements when we detect a UP system.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-10-04 20:23:36 +01:00
Jeremy Kerr
2b0d8c251b ARM: 5880/1: arm: use generic infrastructure for early params
The ARM setup code includes its own parser for early params, there's
also one in the generic init code.

This patch removes __early_init (and related code) from
arch/arm/kernel/setup.c, and changes users to the generic early_init
macro instead.

The generic macro takes a char * argument, rather than char **, so we
need to update the parser functions a little.

Signed-off-by: Jeremy Kerr <jeremy.kerr@canonical.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-02-15 21:39:13 +00:00
Alan Jenkins
e3f28c1333 ARM: use unified discard definition in linker script
Commit 023bf6f "linker script: unify usage of discard definition"
changed the linker scripts for all architectures except for ARM.
I can find no discussion about this ommision, so here are the changes
for ARM.

These changes are exactly parallel to the ia64 case.

"ia64 is notable because it first throws away some ia64 specific
 subsections and then include the rest of the sections into the final
 image, so those sections must be discarded before the inclusion."

Not boot-tested.  In build testing, the modified linker script generated
an identical vmlinux file.

[I would like to be able to rely on this unified discard definition.
 I want to sort the kernel symbol tables to allow faster symbol
 resolution during module loading. The simplest way appears to be
 to generate sorted versions from vmlinux.o, link them in to vmlinux,
 _and discard the original unsorted tables_.

 This work is driven by my x86 netbook, but it is implemented at a
 generic level. It is possible it will benefit some ARM systems also.]

Signed-off-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by-without-testing: Tejun Heo <tj@kernel.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-12-15 16:28:18 +10:30
Nelson Elhage
78d7530ac3 ARM: Clean up linker script using new linker script macros.
This patch is mostly a straightforward translation. The primary side
effect to the resulting vmlinux should be to increase the alignment on
the initramfs to the standard PAGE_SIZE from 32 bytes.

Signed-off-by: Nelson Elhage <nelhage@ksplice.com>
Signed-off-by: Tim Abbott <tabbott@ksplice.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-11-23 20:33:38 +00:00
Tim Abbott
2abc1c50b6 ARM: convert to use __HEAD and HEAD_TEXT macros.
This has the consequence of changing the section name used for head
code from ".text.head" to ".head.text".  Since this commit changes all
users in the architecture, this change should be harmless.

The .text.head output section is eliminated and the head text code is
included at the start of the .init output section.

Signed-off-by: Tim Abbott <tabbott@ksplice.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-11-23 20:33:34 +00:00
Russell King
ae19ffbadc Merge branch 'master' into for-linus 2009-09-22 21:01:40 +01:00
Linus Walleij
bc581770cf ARM: 5580/2: ARM TCM (Tightly-Coupled Memory) support v3
This adds the TCM interface to Linux, when active, it will
detect and report TCM memories and sizes early in boot if
present, introduce generic TCM memory handling, provide a
generic TCM memory pool and select TCM memory for the U300
platform.

See the Documentation/arm/tcm.txt for documentation.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-09-15 22:11:05 +01:00
Tejun Heo
c43768cbb7 Merge branch 'master' into for-next
Pull linus#master to merge PER_CPU_DEF_ATTRIBUTES and alpha build fix
changes.  As alpha in percpu tree uses 'weak' attribute instead of
inline assembly, there's no need for __used attribute.

Conflicts:
	arch/alpha/include/asm/percpu.h
	arch/mn10300/kernel/vmlinux.lds.S
	include/linux/percpu-defs.h
2009-07-04 07:13:18 +09:00
Linus Walleij
f6430a938d [ARM] 5565/2: Use PAGE_SIZE and RO_DATA() in link script
Update the link script for ARM to use PAGE_SIZE instead of hard-
coded 4096. Also the old RODATA macro is deprecated
for the RO_DATA(PAGE_SIZE) macro. As a consequence the PAGE_SIZE
was changed from (1UL << PAGE_SHIFT) to (_AC(1,UL) << PAGE_SHIFT)
because the linker does not understand the "UL" suffix to numeric
constants.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-06-25 14:00:59 +01:00
Tejun Heo
405d967dc7 linker script: throw away .discard section
x86 throws away .discard section but no other archs do.  Also,
.discard is not thrown away while linking modules.  Make every arch
and module linking throw it away.  This will be used to define dummy
variables for percpu declarations and definitions.

This patch is based on Ivan Kokshaysky's alpha percpu patch.

[ Impact: always throw away everything in .discard ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Bryan Wu <cooloney@kernel.org>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Ingo Molnar <mingo@elte.hu>
2009-06-24 15:13:38 +09:00
Catalin Marinas
7436127ce9 [ARM] 5557/1: Discard some ARM.ex*.*exit.text sections when !HOTPLUG or !HOTPLUG_CPU
Not discarding these sections when hotplug isn't available prevents the
kernel from building.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-06-19 16:44:21 +01:00
Catalin Marinas
8c7e65742f arm: Provide _sdata and __bss_stop in the vmlinux.lds.S file
_sdata and __bss_stop are common symbols defined by many architectures
and made available to the kernel via asm-generic/sections.h. Kmemleak
uses these symbols when scanning the data sections.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-05-30 14:00:17 +01:00
Linus Torvalds
0fe41b8982 Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (422 commits)
  [ARM] 5435/1: fix compile warning in sanity_check_meminfo()
  [ARM] 5434/1: ARM: OMAP: Fix mailbox compile for 24xx
  [ARM] pxa: fix the bad assumption that PCMCIA sockets always start with 0
  [ARM] pxa: fix Colibri PXA300 and PXA320 LCD backlight pins
  imxfb: Fix TFT mode
  i.MX21/27: remove ifdef CONFIG_FB_IMX
  imxfb: add clock support
  mxc: add arch_reset() function
  clkdev: add possibility to get a clock based on the device name
  i.MX1: remove fb support from mach-imx
  [ARM] pxa: build arch/arm/plat-pxa/mfp.c only when PXA3xx or ARCH_MMP defined
  Gemini: Add support for Teltonika RUT100
  Gemini: gpiolib based GPIO support v2
  MAINTAINERS: add myself as Gemini architecture maintainer
  ARM: Add Gemini architecture v3
  [ARM] OMAP: Fix compile for omap2_init_common_hw()
  MAINTAINERS: Add myself as Faraday ARM core variant maintainer
  ARM: Add support for FA526 v2
  [ARM] acorn,ebsa110,footbridge,integrator,sa1100: Convert asm/io.h to linux/io.h
  [ARM] collie: fix two minor formatting nits
  ...
2009-03-28 14:03:14 -07:00
Tejun Heo
19390c4d03 linker script: define __per_cpu_load on all SMP capable archs
Impact: __per_cpu_load available on all SMP capable archs

Percpu now requires three symbols to be defined - __per_cpu_load,
__per_cpu_start and __per_cpu_end.  There were three archs which
didn't have it.  Update them as follows.

* powerpc: can use generic PERCPU() macro.  Compile tested for
  powerpc32, compile/boot tested for powerpc64.

* ia64: can use generic PERCPU_VADDR() macro.  __phys_per_cpu_start is
  identical to __per_cpu_load.  Compile tested and symbol table looks
  identical after the change except for the additional __per_cpu_load.

* arm: added explicit __per_cpu_load definition.  Currently uses
  unified .init output section so can't use the generic macro.  Dunno
  whether the unified .init ouput section is required by arch
  peculiarity so I left it alone.  Please break it up and use PERCPU()
  if possible.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Pat Gefre <pfg@sgi.com>
Cc: Russell King <rmk@arm.linux.org.uk>
2009-03-10 16:27:48 +09:00
Catalin Marinas
bff595c15c [ARM] 5383/2: unwind: Add core support for ARM stack unwinding
This patch adds the main functionality for parsing the stack unwinding
information generated by the ARM EABI toolchains. The unwinding
information consists of an index with a pair of words per function and a
table with unwinding instructions. For more information, see "Exception
Handling ABI for the ARM Architecture" at:

http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-19 11:26:24 +00:00
Tejun Heo
74e7904559 linker script: add missing .data.percpu.page_aligned
arm, arm/mach-integrator and powerpc were missing
.data.percpu.page_aligned in their percpu output section definitions.
Add it.

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-01-17 15:26:32 +09:00
Russell King
37efe6427d [ARM] use asm/sections.h
Update to use the asm/sections.h header rather than declaring these
symbols ourselves.  Change __data_start to _data to conform with the
naming found within asm/sections.h.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-12-01 11:53:07 +00:00
Sam Ravnborg
01ba2bdc6b all archs: consolidate init and exit sections in vmlinux.lds.h
This patch consolidate all definitions of .init.text, .init.data
and .exit.text, .exit.data section definitions in
the generic vmlinux.lds.h.

This is a preparational patch - alone it does not buy
us much good.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-01-28 23:21:17 +01:00
Nicolas Pitre
785d3cd286 ARM kprobes: prevent some functions involved with kprobes from being probed
Signed-off-by: Nicolas Pitre <nico@marvell.com>
2008-01-26 15:25:17 +00:00
Fenghua Yu
5fb7dc37dc define new percpu interface for shared data
per cpu data section contains two types of data.  One set which is
exclusively accessed by the local cpu and the other set which is per cpu,
but also shared by remote cpus.  In the current kernel, these two sets are
not clearely separated out.  This can potentially cause the same data
cacheline shared between the two sets of data, which will result in
unnecessary bouncing of the cacheline between cpus.

One way to fix the problem is to cacheline align the remotely accessed per
cpu data, both at the beginning and at the end.  Because of the padding at
both ends, this will likely cause some memory wastage and also the
interface to achieve this is not clean.

This patch:

Moves the remotely accessed per cpu data (which is currently marked
as ____cacheline_aligned_in_smp) into a different section, where all the data
elements are cacheline aligned. And as such, this differentiates the local
only data and remotely accessed data cleanly.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: <linux-arch@vger.kernel.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 10:04:44 -07:00
Sam Ravnborg
ca967258b6 all-archs: consolidate .data section definition in asm-generic
With this consolidation we can now modify the .data
section definition in one spot for all archs.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-05-19 09:11:57 +02:00
Sam Ravnborg
7664709b44 all-archs: consolidate .text section definition in asm-generic
Move definition of .text section to asm-generic.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-05-19 09:11:57 +02:00
Russell King
08fdffd4cf [ARM] Ensure head text is always placed at the start of kernel
Commit 86c0baf123 highlighted that we
may end up with the head text placed elsewhere in the kernel image.
Introduce a new .text.head section to contain the initial kernel
startup code, and always place this section at the beginning of the
kernel image.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-05-08 15:15:45 +01:00
Russell King
4efb448272 [ARM] Shut up warning about init_thread_union
Fix false warning:

WARNING: arch/arm/kernel/init_task.o - Section mismatch:
 reference to .init.task:init_thread_union from .data between
 'init_task' (at offset 0x4) and 'init_sighand'

caused by the section name starting with ".init".

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-05-08 12:39:37 +01:00
Linus Torvalds
c6799ade4a Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (82 commits)
  [ARM] Add comments marking in-use ptrace numbers
  [ARM] Move syscall saving out of the way of utrace
  [ARM] 4360/1: S3C24XX: regs-udc.h remove unused macro
  [ARM] 4358/1: S3C24XX: mach-qt2410.c: remove linux/mmc/protocol.h header
  [ARM] mm 10: allow memory type to be specified with ioremap
  [ARM] mm 9: add additional device memory types
  [ARM] mm 8: define mem_types table L1 bit 4 to be for ARMv6
  [ARM] iop: add missing parens in macro
  [ARM] mm 7: remove duplicated __ioremap() prototypes
  ARM: OMAP: fix OMAP1 mpuio suspend/resume oops
  ARM: OMAP: MPUIO wake updates
  ARM: OMAP: speed up gpio irq handling
  ARM: OMAP: plat-omap changes for 2430 SDP
  ARM: OMAP: gpio object shrinkage, cleanup
  ARM: OMAP: /sys/kernel/debug/omap_gpio
  ARM: OMAP: Implement workaround for GPIO wakeup bug in OMAP2420 silicon
  ARM: OMAP: Enable 24xx GPIO autoidling
  [ARM] 4318/2: DSM-G600 Board Support
  [ARM] 4227/1: minor head.S fixups
  [ARM] 4328/1: Move i.MX UART regs to driver
  ...
2007-05-06 13:20:10 -07:00
Jeremy Fitzhardinge
b6e3590f81 [PATCH] x86: Allow percpu variables to be page-aligned
Let's allow page-alignment in general for per-cpu data (wanted by Xen, and
Ingo suggested KVM as well).

Because larger alignments can use more room, we increase the max per-cpu
memory to 64k rather than 32k: it's getting a little tight.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2007-05-02 19:27:12 +02:00
Russell King
7ab3f8d595 [ARM] Add ability to dump exception stacks to kernel backtraces
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-04-21 20:34:34 +01:00
Nicolas Pitre
e98ff7f6d8 [ARM] 4224/2: allow XIP kernel to boot again
Since commit 2552fc27ff XIP kernels failed
to boot because (_end - PAGE_OFFSET - 1) is much smaller than the size
of the kernel text and data in the XIP case, causing the kernel not to
be entirely mapped.

Even in the non-XIP case, the use of (_end - PAGE_OFFSET - 1) is wrong
because it produces a too large value if TEXT_OFFSET is larger than 1MB.

Finally the original code was performing one loop too many.

Let's break the loop when the section pointer has passed the last byte
of the kernel instead.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-02-25 16:41:38 +00:00
Jean-Paul Saman
67d38229df [PATCH] disable init/initramfs.c: architectures
Update all arch/*/kernel/vmlinux.lds.S to not include space for initramfs
when CONFIG_BLK_DEV_INITRAMFS is not selected.  This saves another 4 kbytes
on most platfoms (some reserve PAGE_SIZE for initramfs).

Signed-off-by: Jean-Paul Saman <jean-paul.saman@nxp.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:25 -08:00
Andrew Morton
61ce1efe6e [PATCH] vmlinux.lds: consolidate initcall sections
Add a vmlinux.lds.h helper macro for defining the eight-level initcall table,
teach all the architectures to use it.

This is a prerequisite for a patch which performs initcall synchronisation for
multithreaded-probing.

Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
[ Added AVR32 as well ]
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-27 15:34:51 -07:00
Jörn Engel
6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Russell King
9641c7cc5a [ARM] nommu: uaccess tweaks
MMUless systems have only one address space for all threads, so
both the usual access_ok() checks, and the exception handling do
not make much sense.

Hence, discard the fixup and exception tables at link time, use
memcpy/memset for the user copy/clearing functions, and define
the permission check macros to be constants.

Some of this patch was derived from the equivalent patch by
Hyok S. Choi.

Signed-off-by: Hyok S. Choi <hyok.choi@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-06-28 17:59:46 +01:00
Russell King
9d4f13e531 [ARM] Make kernel link address depend on PAGE_OFFSET
We are coding the kernel link address into the makefiles, which is
invisibly dependent on PAGE_OFFSET.  If PAGE_OFFSET is changed, the
makefiles also need to be changed.

Make adjustments such that the makefiles encode just the offset from
PAGE_OFFSET for the kernel link address, and use PAGE_OFFSET in the
linker scripts directly.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-01-03 17:28:33 +00:00
Russell King
728f5c076a [ARM] Improve comment about ASSERT()s in vmlinux.lds.S
Provide folk with an idea what to do if the ASSERT statements fail
with their linker.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-11-17 16:43:14 +00:00
Nicolas Pitre
37d07b72ef [ARM] 3061/1: cleanup the XIP link address mess
Patch from Nicolas Pitre

Since vmlinux.lds.S is preprocessed, we can use the defines already
present in asm/memory.h (allowed by patch #3060) for the XIP kernel link
address instead of relying on a duplicated Makefile hardcoded value, and
also get rid of its dependency on awk to handle it at the same time.

While at it let's clean XIP stuff even further and make things clearer
in head.S with a nice code reduction.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-10-29 21:44:56 +01:00