linux/arch/powerpc
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
..
boot Merge remote branch 'jwb/next' into next 2011-03-17 17:59:01 +11:00
configs powerpc/8xx: remove obsolete mgsuvd board 2011-03-15 10:11:27 -05:00
include/asm remove dma64_addr_t 2011-03-23 19:47:18 -07:00
kernel percpu: Always align percpu output section to PAGE_SIZE 2011-03-24 18:50:09 +01:00
kvm KVM: PPC: Fix SPRG get/set for Book3S and BookE 2011-03-17 13:08:25 -03:00
lib powerpc: Ensure the else case of feature sections will fit 2011-01-21 14:08:33 +11:00
math-emu powerpc/85xx: Fix SPE float to integer conversion failure 2011-03-15 13:48:15 -05:00
mm Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2011-03-18 06:31:43 -07:00
oprofile tree-wide: fix comment/printk typos 2010-11-01 15:38:34 -04:00
platforms Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2011-03-18 06:31:43 -07:00
sysdev rapidio: remove mport resource reservation from common RIO code 2011-03-23 19:46:43 -07:00
xmon powerpc/Makefiles: Change to new flag variables 2010-10-13 16:19:22 +11:00
Kconfig rapidio: modify configuration to support PCI-SRIO controller 2011-03-23 19:46:42 -07:00
Kconfig.debug powerpc: Unconditionally enabled irq stacks 2010-06-15 15:02:37 +10:00
Makefile powerpc: Fix typo in uImage target 2010-08-24 15:26:32 +10:00
relocs_check.pl