Commit Graph

22 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
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
Denys Vlasenko b6f4e451de Rename special text sections in arch/frv from .text.XXX to .text..XXX.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-03-03 11:26:01 +01:00
Denys Vlasenko 1360e07070 Rename .bss.stack to .bss..stack.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-03-03 11:25:59 +01:00
Nelson Elhage 9c88b25bcf frv: clean up linker script using new linker script macros.
This is largely a straightforward conversion. The patch results in
fewer output sections, and some data being reordered, but should have
no functional impact.

Also, note that this patch moves some data (namely, init_task and
cacheline-aligned) inside [_sdata,_edata].

Because frv already builds using -ffunction-sections -fdata-sections,
we can't use BSS_SECTION or RW_DATA_SECTION yet, since they do not
currently include the required .bss.* and .data.* sections.

Signed-off-by: Nelson Elhage <nelhage@ksplice.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Tim Abbott <tabbott@ksplice.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-18 13:57:18 -07:00
Nelson Elhage 88ddb81e0f frv: remove unused .altinstructions code
It appears that frv copied the .altinstructions definitions in its linker
script from x86. Since frv doesn't put anything in those sections, this
is just dead code.

Signed-off-by: Nelson Elhage <nelhage@ksplice.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Tim Abbott <tabbott@ksplice.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-18 13:57:18 -07:00
Tejun Heo 023bf6f1b8 linker script: unify usage of discard definition
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 <tj@kernel.org>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Tested-by: Michal Simek <monstr@monstr.eu>
Cc: linux-arch@vger.kernel.org
Cc: Michal Simek <monstr@monstr.eu>
Cc: microblaze-uclinux@itee.uq.edu.au
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Tony Luck <tony.luck@intel.com>
2009-07-09 11:27:40 +09:00
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
Tim Abbott b6a8d95c95 frv: convert frv to use __HEAD and HEAD_TEXT macros.
This has the consequence of changing the section name use for head
code from ".text.head" to ".head.text".  Since this commit changes all
users in the architecture, this change should be harmless.

Signed-off-by: Tim Abbott <tabbott@mit.edu>
Cc: David Howells <dhowells@redhat.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-26 09:20:38 -07:00
David Howells 2d0e2baa25 FRV: Drop the .data.idt section for FRV
There is no .data.idt section for FRV, so drop it from the linker script.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-20 19:58:16 -08:00
David Howells d897d2b597 FRV: Fix up parse error in linker script
Fix up parse error in FRV linker script, presumably introduced through changes
to the INIT_TEXT and EXIT_TEXT macros.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-13 08:26:01 -08:00
David Howells 7038220aa5 FRV: permit the memory to be located elsewhere in NOMMU mode
Permit the memory to be located somewhere other than address 0xC0000000 in
NOMMU mode.  The configuration options are already present, it just
requires wiring up in the linker script.

Note that only a limited set of locations of runtime addresses are available
because of the way the CPU protection registers work.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 09:44:20 -08:00
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
David Howells 3c835670ab FRV: arrange things such that BRA can reach from the trap table
Arrange the sections in the FRV arch so that a BRA instruction with a
16-bit displacement can always reach from the trap table to entry.S,
tlb-miss.S and break.S.

The problem otherwise is that the linker can insert sufficient code between
the slots in the trap table and the targets of the branch instructions in
those slots that the displacement field in the instruction isn't
sufficiently large.  This is because the branch targets were in the .text
section along with most of the other code in the kernel.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-29 09:24:54 -08:00
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
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
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
David Howells 41be6aef38 [PATCH] frv: miscellaneous changes
Fix a number of miscellanous items:

 (1) Declare lock sections in the linker script.

 (2) Recurse in the correct manner in the arch makefile.

 (3) asm/bug.h requires asm/linkage.h to be included first. One C file puts
     asm/bug.h first.

 (4) Add an empty RTC header file to avoid missing header file errors.

 (5) sg_dma_address() should use the dma_address member of a scatter list.

 (6) Add trivial pci_unmap support.

 (7) Add pgprot_noncached()

 (8) Discard u_quad_t.

 (9) Use ~0UL rather than ULONG_MAX in unistd.h in case the latter isn't
     declared.

(10) Add an empty VGA header file to avoid missing header file errors.

(11) Add an XOR header file to use the generic XOR stuff.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:38 -08:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00