mm: get 7% more pages in a pagevec
authorMatthew Wilcox <willy@infradead.org>
Thu, 1 Feb 2018 00:17:40 +0000 (16:17 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 1 Feb 2018 01:18:37 +0000 (17:18 -0800)
commit146500e9604cece72d4bed1cd15fac789220c795
tree4ba9664cfc70ede864bc351129f471a9310f1c4f
parent977fbdcd5986c9ff700bf276644d2b1973a53348
mm: get 7% more pages in a pagevec

We don't have to use an entire 'long' for the number of elements in the
pagevec; we know it's a number between 0 and 14 (now 15).  So we can
store it in a char, and then the bool packs next to it and we still have
two or six bytes of padding for more elements in the header.  That gives
us space to cram in an extra page.

Link: http://lkml.kernel.org/r/20171206022521.GM26021@bombadil.infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
include/linux/pagevec.h