linux/arch/x86
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
..
boot Merge branches 'x86/apic', 'x86/cleanups', 'x86/cpufeature', 'x86/crashdump', 'x86/debug', 'x86/defconfig', 'x86/detect-hyper', 'x86/doc', 'x86/dumpstack', 'x86/early-printk', 'x86/fpu', 'x86/idle', 'x86/io', 'x86/memory-corruption-check', 'x86/microcode', 'x86/mm', 'x86/mtrr', 'x86/nmi-watchdog', 'x86/pat2', 'x86/pci-ioapic-boot-irq-quirks', 'x86/ptrace', 'x86/quirks', 'x86/reboot', 'x86/setup-memory', 'x86/signal', 'x86/sparse-fixes', 'x86/time', 'x86/uv' and 'x86/xen' into x86/core 2008-12-23 16:27:23 +01:00
configs x86: revert CONFIG_RELOCATABLE=y defconfig change 2008-12-18 20:57:29 +01:00
crypto crypto: crc32c-intel - Switch to shash 2008-12-25 11:01:37 +11:00
ia32 x86: introducing asm/sys_ia32.h 2008-12-29 13:18:40 +01:00
include/asm Merge branch 'cpus4096-for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-01-03 12:04:39 -08:00
kernel Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-01-05 19:03:11 -08:00
kvm KVM: change KVM to use IOMMU API 2009-01-03 14:11:07 +01:00
lguest Merge branch 'cpus4096-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-01-02 11:44:09 -08:00
lib Merge commit 'v2.6.28-rc2' into core/locking 2008-10-28 16:54:49 +01:00
mach-default x86: mach-default setup.c cleanups 2008-12-29 13:18:39 +01:00
mach-generic x86 smp: modify send_IPI_mask interface to accept cpumask_t pointers 2008-12-16 17:40:56 -08:00
mach-rdc321x removed unused #include <linux/version.h>'s 2008-08-23 12:14:12 -07:00
mach-voyager x86: cleanup some remaining usages of NR_CPUS where s/b nr_cpu_ids 2009-01-03 19:00:55 +01:00
math-emu
mm mm: show node to memory section relationship with symlinks in sysfs 2009-01-06 15:59:00 -08:00
oprofile Merge branch 'oprofile-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-12-30 17:31:25 -08:00
pci x86, pci: move arch/x86/pci/pci.h to arch/x86/include/asm/pci_x86.h 2008-12-29 18:17:36 +01:00
power x86, hibernate: fix breakage on x86_32 with CONFIG_NUMA set 2008-11-12 23:28:51 +01:00
scripts allow stripping of generated symbols under CONFIG_KALLSYMS_ALL 2008-12-19 22:47:10 +01:00
vdso Merge branch 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6 2008-12-28 12:33:21 -08:00
video
xen Merge branch 'cputime' of git://git390.osdl.marist.edu/pub/scm/linux-2.6 2009-01-03 11:56:24 -08:00
Kconfig Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-cpumask into merge-rr-cpumask 2009-01-03 18:53:31 +01:00
Kconfig.cpu X86_DEBUGCTLMSR won't work on uml 2009-01-05 17:41:45 -08:00
Kconfig.debug Merge branch 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-12-28 12:21:10 -08:00
Makefile x86, um: ... and asm-x86 move 2008-10-22 22:55:20 -07:00
Makefile_32.cpu x86: merge winchip-2 and winchip-2a cpu choices 2008-10-13 10:22:48 +02:00