[PATCH 00/10] Support free page filtering looking up mem_map array

[HATAYAMA Daisuke]

This patch set implements filtering free pages looking up mem_map
array instead of free lists. This is compatible for cyclic mode
because looking up mem_map can be divided into cycles. On the other
hand, dividing free pages contaiend in free lists is difficult since
they are not sorted in physical-address order.

Unlike RFC version, the logic used is automatically selected at
runtime according to the current mode. On cyclic mode, mem_map array
logic is used. On non-cyclic mode, free list logic is used.

The RFC version is:
http://lists.infradead.org/pipermail/kexec/2012-June/006441.html

* TODO

Add the following values in VMCOREINFO on the upstream kernel. These
are used in the mem_map logic.

  - OFFSET(page._mapcount)
  - OFFSET(page.private)
  - SIZE(pageflags)
  - NUMBER(PG_buddy)
  - NUMBER(PG_slab)
  - NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE)

* Test

I tested this patch set on the following kernel versions.

- 3.4
- 3.1
- 2.6.38
- 2.6.32
- 2.6.18

On the test, I manually specified VMCOREINFO while extending it with
the following values according to the kernel versions.

- 3.1, 3.4
NUMBER(PG_slab)=7
SIZE(pageflags)=4
OFFSET(page._mapcount)=24
OFFSET(page.private)=48
NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE)=-128

- 2.6.38
SIZE(pageflags)=4
OFFSET(page._mapcount)=12
OFFSET(page.private)=16
NUMBER(PG_slab)=7
NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE)=-2

- 2.6.32
NUMBER(PG_slab)=7
NUMBER(PG_buddy)=19
OFFSET(page._mapcount)=12
OFFSET(page.private)=16
SIZE(pageflags)=4

- 2.6.18
NUMBER(PG_slab)=7
NUMBER(PG_buddy)=19
OFFSET(page._mapcount)=12
OFFSET(page.private)=16

---

HATAYAMA Daisuke (10):
      Print warning about cyclic buffer overrun if it can happen
      Add page_is_buddy for old kernels
      Add page_is_buddy for PG_buddy
      Add page_is_buddy for recent kernels
      Exclude free pages by looking up mem_map array
      Add hardcoded page flag values
      Add debuginfo-related processing for VMCOREINFO/VMLINUX
      Add new parameters to various tables
      Add debuginfo interface for enum type size
      Move page flags setup for old kernels after debuginfo initialization


 dwarf_info.c   |   18 ++++++
 dwarf_info.h   |    1 
 makedumpfile.c |  170 ++++++++++++++++++++++++++++++++++++++++++++++++++++----
 makedumpfile.h |   29 +++++++++-
 4 files changed, 204 insertions(+), 14 deletions(-)

-- 

Thanks.
HATAYAMA, Daisuke