mm: remove cold parameter from free_hot_cold_page*
authorMel Gorman <mgorman@techsingularity.net>
Thu, 16 Nov 2017 01:37:59 +0000 (17:37 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 16 Nov 2017 02:21:06 +0000 (18:21 -0800)
commit2d4894b5d2ae0fe1725ea7abd57b33bfbbe45492
treeab55401d2d6181491fa9e767561275c2992680e6
parentc6f92f9fbe7dbcc8903a67229aa88b4077ae4422
mm: remove cold parameter from free_hot_cold_page*

Most callers users of free_hot_cold_page claim the pages being released
are cache hot.  The exception is the page reclaim paths where it is
likely that enough pages will be freed in the near future that the
per-cpu lists are going to be recycled and the cache hotness information
is lost.  As no one really cares about the hotness of pages being
released to the allocator, just ditch the parameter.

The APIs are renamed to indicate that it's no longer about hot/cold
pages.  It should also be less confusing as there are subtle differences
between them.  __free_pages drops a reference and frees a page when the
refcount reaches zero.  free_hot_cold_page handled pages whose refcount
was already zero which is non-obvious from the name.  free_unref_page
should be more obvious.

No performance impact is expected as the overhead is marginal.  The
parameter is removed simply because it is a bit stupid to have a useless
parameter copied everywhere.

[mgorman@techsingularity.net: add pages to head, not tail]
Link: http://lkml.kernel.org/r/20171019154321.qtpzaeftoyyw4iey@techsingularity.net
Link: http://lkml.kernel.org/r/20171018075952.10627-8-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
arch/powerpc/mm/mmu_context_book3s64.c
arch/powerpc/mm/pgtable_64.c
arch/sparc/mm/init_64.c
arch/tile/mm/homecache.c
include/linux/gfp.h
include/trace/events/kmem.h
mm/page_alloc.c
mm/rmap.c
mm/swap.c
mm/vmscan.c