mm/page_alloc: optimize code layout for __alloc_pages_bulk

Looking at perf-report and ASM-code for __alloc_pages_bulk() it is clear
that the code activated is suboptimal.  The compiler guesses wrong and
places unlikely code at the beginning.  Due to the use of WARN_ON_ONCE()
macro the UD2 asm instruction is added to the code, which confuse the
I-cache prefetcher in the CPU.

[[email protected]: minor changes and rebasing]

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Jesper Dangaard Brouer <[email protected]>
Signed-off-by: Mel Gorman <[email protected]>
Reviewed-by: Alexander Lobakin <[email protected]>
Acked-By: Vlastimil Babka <[email protected]>
Cc: Alexander Duyck <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Chuck Lever <[email protected]>
Cc: David Miller <[email protected]>
Cc: Ilias Apalodimas <[email protected]>
Cc: Matthew Wilcox (Oracle) <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions