mm: meminit: make __early_pfn_to_nid SMP-safe and introduce meminit_pfn_in_nid

__early_pfn_to_nid() use static variables to cache recent lookups as
memblock lookups are very expensive but it assumes that memory
initialisation is single-threaded.  Parallel initialisation of struct
pages will break that assumption so this patch makes __early_pfn_to_nid()
SMP-safe by requiring the caller to cache recent search information.
early_pfn_to_nid() keeps the same interface but is only safe to use early
in boot due to the use of a global static variable.  meminit_pfn_in_nid()
is an SMP-safe version that callers must maintain their own state for.

Signed-off-by: Mel Gorman <[email protected]>
Tested-by: Nate Zimmer <[email protected]>
Tested-by: Waiman Long <[email protected]>
Tested-by: Daniel J Blueman <[email protected]>
Acked-by: Pekka Enberg <[email protected]>
Cc: Robin Holt <[email protected]>
Cc: Nate Zimmer <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Waiman Long <[email protected]>
Cc: Scott Norton <[email protected]>
Cc: "Luck, Tony" <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions