mm: clarify why we want kmalloc before falling backto vmallock
authorMichal Hocko <mhocko@suse.com>
Fri, 2 Jun 2017 21:46:19 +0000 (14:46 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 2 Jun 2017 22:07:37 +0000 (15:07 -0700)
commit4f4f2ba9c531b3d7cee293dd3654ba3b86e7d220
treee76d33e876e50dcbeb4dc88a919003657911b785
parent60b0a8c3d2480f3b57282b47b7cae7ee71c48635
mm: clarify why we want kmalloc before falling backto vmallock

While converting drm_[cm]alloc* helpers to kvmalloc* variants Chris
Wilson has wondered why we want to try kmalloc before vmalloc fallback
even for larger allocations requests.  Let's clarify that one larger
physically contiguous block is less likely to fragment memory than many
scattered pages which can prevent more large blocks from being created.

[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/20170517080932.21423-1-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/util.c