[PATCH 0/2] Replace nr_node_ids for loop with for_each_node

Raghavendra K T raghavendra.kt at linux.vnet.ibm.com
Wed Sep 9 04:31:45 AEST 2015

Many places in the kernel use 'for' loop with nr_node_ids. For the architectures
which supports sparse numa ids, this will result in some unnecessary allocations
for non existing nodes.
(for e.g., numa node numbers such as 0,1,16,17 is common in powerpc.)

So replace the for loop with for_each_node so that allocations happen only for
existing numa nodes.

Please note that, though there are many places where nr_node_ids is used,
current patchset uses for_each_node only for slowpath to avoid find_next_bit

Raghavendra K T (2):
  mm: Replace nr_node_ids for loop with for_each_node in list lru
  powerpc:numa Do not allocate bootmem memory for non existing nodes

 arch/powerpc/mm/numa.c |  2 +-
 mm/list_lru.c          | 23 +++++++++++++++--------
 2 files changed, 16 insertions(+), 9 deletions(-)


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