linux/arch/sparc64
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 [SPARC64]: Add .gitignore file for sparc64 boot images. 2006-02-05 00:15:11 -08:00
kernel define new percpu interface for shared data 2007-07-19 10:04:44 -07:00
lib [SPARC64]: More sensible udelay implementation. 2007-07-16 04:05:02 -07:00
math-emu [SPARC64] math-emu: Delete debugging printk left by previous commit. 2006-03-20 01:13:53 -08:00
mm mm: fault feedback #2 2007-07-19 10:04:41 -07:00
oprofile [PATCH] Move Kprobes and Oprofile to "Instrumentation Support" menu 2005-11-07 07:53:35 -08:00
prom [SPARC64]: Initial LDOM cpu hotplug support. 2007-07-16 04:04:40 -07:00
solaris unregister_chrdev(): ignore the return value 2007-07-19 10:04:43 -07:00
Kconfig [SPARC]: Mark sparc and sparc64 as not having virt_to_bus 2007-07-18 01:20:22 -07:00
Kconfig.debug [SPARC64]: Add irqtrace/stacktrace/lockdep support. 2006-12-10 02:39:09 -08:00
Makefile [SPARC64]: Stop putting -finline-limit=XXX into CFLAGS 2005-12-20 14:53:05 -08:00
defconfig [SPARC64]: Update defconfig. 2007-07-17 12:18:16 -07:00