linux-toradex.git/arch/xtensa/kernel/vmlinux.lds.S, branch v3.3.5

percpu: Always align percpu output section to PAGE_SIZE

2011-03-24T17:50:09+00:00

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 
Acked-by: Mike Frysinger 
Cc: uclinux-dist-devel@blackfin.uclinux.org
Cc: David Howells 
Cc: Jeff Dike 
Cc: user-mode-linux-devel@lists.sourceforge.net

percpu: align percpu readmostly subsection to cacheline

2011-01-25T13:26:50+00:00

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 
Cc: Shaohua Li

xtensa: Cleanup linker script using new linker script macros.

2009-09-25T00:16:21+00:00

Signed-off-by: Tim Abbott 
Cc: Chris Zankel 
Acked-by: Sam Ravnborg 
Signed-off-by: Linus Torvalds

linker script: unify usage of discard definition

2009-07-09T02:27:40+00:00

Discarded sections in different archs share some commonality but have
considerable differences.  This led to linker script for each arch
implementing its own /DISCARD/ definition, which makes maintaining
tedious and adding new entries error-prone.

This patch makes all linker scripts to move discard definitions to the
end of the linker script and use the common DISCARDS macro.  As ld
uses the first matching section definition, archs can include default
discarded sections by including them earlier in the linker script.

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.

defconfig compile tested for x86, x86-64, powerpc, powerpc64, ia64,
alpha, sparc, sparc64 and s390.  Michal Simek tested microblaze.

Signed-off-by: Tejun Heo 
Acked-by: Paul Mundt 
Acked-by: Mike Frysinger 
Tested-by: Michal Simek 
Cc: linux-arch@vger.kernel.org
Cc: Michal Simek 
Cc: microblaze-uclinux@itee.uq.edu.au
Cc: Sam Ravnborg 
Cc: Tony Luck

linker script: throw away .discard section

2009-06-24T06:13:38+00:00

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 
Cc: Ivan Kokshaysky 
Cc: Richard Henderson 
Cc: Russell King 
Cc: Haavard Skinnemoen 
Cc: Bryan Wu 
Cc: Mikael Starvik 
Cc: Jesper Nilsson 
Cc: David Howells 
Cc: Yoshinori Sato 
Cc: Tony Luck 
Cc: Hirokazu Takata 
Cc: Geert Uytterhoeven 
Cc: Michal Simek 
Cc: Ralf Baechle 
Cc: Kyle McMartin 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Martin Schwidefsky 
Cc: Heiko Carstens 
Cc: Paul Mundt 
Cc: David S. Miller 
Cc: Jeff Dike 
Cc: Chris Zankel 
Cc: Rusty Russell 
Cc: Ingo Molnar

xtensa: Fix linker script to include .literal sections

2009-05-12T06:40:33+00:00

Fix resembles implementation from Marc Gauthier and Piet Denaly:

In the Xtensa architecture, assembly generates literals which must always
precede the code (the L32R instruction that loads them only uses negative
PC-relative offsets).  For any *.text section, literals are placed in a
corresponding *.literal section.  The linker script (vmlinux.lds) must
place these in the correct order.  It must also combine them, when the
*.text section can be larger than L32R's 256 kB range.

For example, this doesn't work:  *(.literal) *(.text) because L32R
instructions at the end of .text can't reach the literals.

The linker can solve this if they are combined in parentheses, like this:
       *(.literal .text)
because it is now allowed mix literals in .text to bring them in range.

None of this is done by standard vmlinux.lds.h macros such as TEXT_TEXT
and INIT_TEXT.  To avoid replicating the logic of that header file, we
instead post-process the generated linker script to convert *(xxx.text)
to *(xxx.literal xxx.text) for the following text sections:
       .text .ref.text .*init.text .*exit.text .text.*
using a sed script.  To do this we must override the default rule for
vmlinux.lds (see scripts/Makefile.build and the top-level Makefile)
to insert this extra step.

Signed-off-by: Marc Gauthier 
Signed-off-by: Pete Delaney 
Signed-off-by: Chris Zankel

xtensa: convert to use __HEAD and HEAD_TEXT macros.

2009-04-26T16:20:38+00:00

Signed-off-by: Tim Abbott 
Cc: Chris Zankel 
Acked-by: Sam Ravnborg 
Signed-off-by: Linus Torvalds

xtensa: let platform override KERNELOFFSET

2009-04-03T06:43:49+00:00

The linker script should not assume a fix offset in memory for the
kernel, this is platform-specific, so let the platform set it.

Signed-off-by: Johannes Weiner 
Signed-off-by: Chris Zankel

xtensa: move headers files to arch/xtensa/include

2008-11-06T18:25:09+00:00

Move all header files for xtensa to arch/xtensa/include and platform and
variant header files to the appropriate arch/xtensa/platforms/ and
arch/xtensa/variants/ directories.

Moving the files gets also rid of all uses of symlinks in the Makefile.

This has been completed already for the majority of the architectures
and xtensa is one out of six missing.

Signed-off-by: Sam Ravnborg 
Signed-off-by: Chris Zankel

[XTENSA] Add missing RELOCATE_ENTRY for debug vector

2008-02-14T01:25:14+00:00

We also need to relocate the debug vector if in RAM.

Signed-off-by: Marc Gauthier