linux/arch/powerpc/mm
Gary Hade c04fc586c1 mm: show node to memory section relationship with symlinks in sysfs
Show node to memory section relationship with symlinks in sysfs

Add /sys/devices/system/node/nodeX/memoryY symlinks for all
the memory sections located on nodeX.  For example:
/sys/devices/system/node/node1/memory135 -> ../../memory/memory135
indicates that memory section 135 resides on node1.

Also revises documentation to cover this change as well as updating
Documentation/ABI/testing/sysfs-devices-memory to include descriptions
of memory hotremove files 'phys_device', 'phys_index', and 'state'
that were previously not described there.

In addition to it always being a good policy to provide users with
the maximum possible amount of physical location information for
resources that can be hot-added and/or hot-removed, the following
are some (but likely not all) of the user benefits provided by
this change.
Immediate:
  - Provides information needed to determine the specific node
    on which a defective DIMM is located.  This will reduce system
    downtime when the node or defective DIMM is swapped out.
  - Prevents unintended onlining of a memory section that was
    previously offlined due to a defective DIMM.  This could happen
    during node hot-add when the user or node hot-add assist script
    onlines _all_ offlined sections due to user or script inability
    to identify the specific memory sections located on the hot-added
    node.  The consequences of reintroducing the defective memory
    could be ugly.
  - Provides information needed to vary the amount and distribution
    of memory on specific nodes for testing or debugging purposes.
Future:
  - Will provide information needed to identify the memory
    sections that need to be offlined prior to physical removal
    of a specific node.

Symlink creation during boot was tested on 2-node x86_64, 2-node
ppc64, and 2-node ia64 systems.  Symlink creation during physical
memory hot-add tested on a 2-node x86_64 system.

Signed-off-by: Gary Hade <garyhade@us.ibm.com>
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:00 -08:00
..
40x_mmu.c powerpc/40x: Limit allocable DRAM during early mapping 2008-11-13 10:10:56 -05:00
44x_mmu.c powerpc: rework 4xx PTE access and TLB miss 2008-07-09 13:36:17 -04:00
Makefile powerpc/mm: Split low level tlb invalidate for nohash processors 2008-12-21 14:21:16 +11:00
fault.c Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc 2008-12-28 16:54:33 -08:00
fsl_booke_mmu.c powerpc/85xx: fix build warning, remove silly cast 2008-09-16 10:01:35 -05:00
gup.c powerpc: Get USE_STRICT_MM_TYPECHECKS working again 2008-10-14 10:35:27 +11:00
hash_low_32.S powerpc: Fix missing 'blr' in _tlbia() 2008-12-21 02:54:25 -07:00
hash_low_64.S powerpc: Free a PTE bit on ppc64 with 64K pages 2008-06-30 22:30:53 +10:00
hash_native_64.c [POWERPC] Use 1TB segments 2007-10-12 14:05:17 +10:00
hash_utils_64.c powerpc: Don't use a 16G page if beyond mem= limits 2008-10-22 15:01:21 +11:00
hugetlbpage.c mm: report the MMU pagesize in /proc/pid/smaps 2009-01-06 15:58:58 -08:00
init_32.c powerpc/32: Add the ability for a classic ppc kernel to be loaded at 32M 2008-12-23 15:13:29 +11:00
init_64.c powerpc: Get USE_STRICT_MM_TYPECHECKS working again 2008-10-14 10:35:27 +11:00
mem.c mm: show node to memory section relationship with symlinks in sysfs 2009-01-06 15:59:00 -08:00
mmap.c Detach sched.h from mm.h 2007-05-21 09:18:19 -07:00
mmu_context_hash32.c powerpc/mm: Split mmu_context handling 2008-12-21 14:21:15 +11:00
mmu_context_hash64.c powerpc/mm: Split mmu_context handling 2008-12-21 14:21:15 +11:00
mmu_context_nohash.c powerpc/mm: Runtime allocation of mmu context maps for nohash CPUs 2008-12-21 14:21:16 +11:00
mmu_decl.h powerpc/mm: Split low level tlb invalidate for nohash processors 2008-12-21 14:21:16 +11:00
numa.c powerpc: Fix bootmem reservation on uninitialized node 2008-12-16 13:48:18 +11:00
pgtable.c powerpc: Use RCU based pte freeing mechanism for all powerpc 2008-12-03 20:46:35 +11:00
pgtable_32.c powerpc/44x: Support 16K/64K base page sizes on 44x 2008-12-29 09:53:25 +11:00
pgtable_64.c powerpc ioremap_prot 2008-07-24 10:47:15 -07:00
ppc_mmu_32.c powerpc/32: Add the ability for a classic ppc kernel to be loaded at 32M 2008-12-23 15:13:29 +11:00
slb.c [POWERPC] vmemmap fixes to use smaller pages 2008-05-15 20:49:25 +10:00
slb_low.S [POWERPC] vmemmap fixes to use smaller pages 2008-05-15 20:49:25 +10:00
slice.c Merge commit 'origin/master' 2008-07-16 11:07:59 +10:00
stab.c [POWERPC] Fix sparse warnings in arch/powerpc/mm 2008-05-14 22:31:46 +10:00
subpage-prot.c [POWERPC] Provide a way to protect 4k subpages when using 64k pages 2008-01-24 10:06:01 +11:00
tlb_hash32.c powerpc/mm: Add SMP support to no-hash TLB handling 2008-12-21 14:21:16 +11:00
tlb_hash64.c powerpc/mm: Rename tlb_32.c and tlb_64.c to tlb_hash32.c and tlb_hash64.c 2008-12-16 15:53:30 +11:00
tlb_nohash.c powerpc/mm: Add SMP support to no-hash TLB handling 2008-12-21 14:21:16 +11:00
tlb_nohash_low.S powerpc/44x: No need to mask MSR:CE, ME or DE in _tlbil_va on 440 2008-12-21 14:21:16 +11:00