linux/arch/alpha
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
..
boot parse errors in ifdefs 2007-06-01 08:18:28 -07:00
kernel define new percpu interface for shared data 2007-07-19 10:04:44 -07:00
lib missing exports of csum_... 2007-07-17 11:01:07 -07:00
math-emu Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
mm mm: fault feedback #2 2007-07-19 10:04:41 -07:00
oprofile [PATCH] oprofile: Fix unnecessary cleverness 2006-06-26 09:58:17 -07:00
defconfig [PATCH] update all defconfigs for ARCH_DISCONTIGMEM_ENABLE 2005-06-23 09:45:02 -07:00
Kconfig PCI: Only build PCI syscalls on architectures that want them 2007-07-11 16:02:13 -07:00
Kconfig.debug kconfig: centralize the selection of semaphore debugging in lib/Kconfig.debug 2007-05-08 11:15:00 -07:00
Makefile kbuild: alpha,x86_64 use generic asm-offsets.h support 2005-09-09 21:28:48 +02:00