linux/arch/s390
Tony Luck fc6daaf931 mm/memblock: add extra "flags" to memblock to allow selection of memory based on attribute
Some high end Intel Xeon systems report uncorrectable memory errors as a
recoverable machine check.  Linux has included code for some time to
process these and just signal the affected processes (or even recover
completely if the error was in a read only page that can be replaced by
reading from disk).

But we have no recovery path for errors encountered during kernel code
execution.  Except for some very specific cases were are unlikely to ever
be able to recover.

Enter memory mirroring. Actually 3rd generation of memory mirroing.

Gen1: All memory is mirrored
	Pro: No s/w enabling - h/w just gets good data from other side of the
	     mirror
	Con: Halves effective memory capacity available to OS/applications

Gen2: Partial memory mirror - just mirror memory begind some memory controllers
	Pro: Keep more of the capacity
	Con: Nightmare to enable. Have to choose between allocating from
	     mirrored memory for safety vs. NUMA local memory for performance

Gen3: Address range partial memory mirror - some mirror on each memory
      controller
	Pro: Can tune the amount of mirror and keep NUMA performance
	Con: I have to write memory management code to implement

The current plan is just to use mirrored memory for kernel allocations.
This has been broken into two phases:

1) This patch series - find the mirrored memory, use it for boot time
   allocations

2) Wade into mm/page_alloc.c and define a ZONE_MIRROR to pick up the
   unused mirrored memory from mm/memblock.c and only give it out to
   select kernel allocations (this is still being scoped because
   page_alloc.c is scary).

This patch (of 3):

Add extra "flags" to memblock to allow selection of memory based on
attribute.  No functional changes

Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Xiexiuqi <xiexiuqi@huawei.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-24 17:49:44 -07:00
..
appldata s390: appldata: drop owner assignment from platform_drivers 2014-10-20 16:20:13 +02:00
boot s390: remove "64" suffix from a couple of files 2015-03-25 11:49:34 +01:00
configs s390: update default configuration 2015-01-22 12:16:09 +01:00
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2015-05-22 14:26:36 -07:00
hypfs s390/sclp: unify basic sclp access by exposing "struct sclp" 2015-05-13 09:58:17 +02:00
include mm: clarify that the function operates on hugepage pte 2015-06-24 17:49:44 -07:00
kernel mm/memblock: add extra "flags" to memblock to allow selection of memory based on attribute 2015-06-24 17:49:44 -07:00
kvm The bulk of the changes here is for x86. And for once it's not 2015-06-24 09:36:49 -07:00
lib s390: remove "64" suffix from mem64.S and swsusp_asm64.S 2015-03-25 11:49:51 +01:00
mm mm/hugetlb: reduce arch dependent code about huge_pmd_unshare 2015-06-24 17:49:41 -07:00
net s390/bpf: fix bpf frame pointer setup 2015-06-03 19:31:39 -07:00
oprofile s390: remove 31 bit support 2015-03-25 11:49:33 +01:00
pci s390/pci: improve handling of hotplug event 0x301 2015-06-18 15:45:54 +02:00
defconfig s390: update default configuration 2015-01-22 12:16:09 +01:00
Kbuild s390: remove 31 bit support 2015-03-25 11:49:33 +01:00
Kconfig s390/bpf: add dependency to z196 features 2015-04-23 16:55:50 +02:00
Kconfig.debug Kconfig: consolidate CONFIG_DEBUG_STRICT_USER_COPY_CHECKS 2013-04-30 17:04:09 -07:00
Makefile s390: remove 31 bit support 2015-03-25 11:49:33 +01:00