01 May, 2010

1 commit

• b0c9778b1   percpu: implement kernel memory based chunk allocation ... Browse Code »

  Implement an alternate percpu chunk management based on kernel memeory
  for nommu SMP architectures. Instead of mapping into vmalloc area,
  chunks are allocated as a contiguous kernel memory using
  alloc_pages(). As such, percpu allocator on nommu will have the
  following restrictions.

  * It can't fill chunks on-demand page-by-page. It has to allocate
  each chunk fully upfront.

  * It can't support sparse chunk for NUMA configurations. SMP w/o mmu
  is crazy enough. Let's hope no one does NUMA w/o mmu. :-P

  * If chunk size isn't power-of-two multiple of PAGE_SIZE, the
  unaligned amount will be wasted on each chunk. So, archs which use
  this better align chunk size.

  For instructions on how to use this, read the comment on top of
  mm/percpu-km.c.

  Signed-off-by: Tejun Heo
  Reviewed-by: David Howells
  Cc: Graff Yang
  Cc: Sonic Zhang

  Tejun Heo

  2010-05-01 14:30:50 +0800