Three vendor hooks are provided to extend struct swap_slots_cache.
The extended data are used to record the information of the
specified reclaimed swap location:
1) android_vh_alloc_swap_slot_cache, replace the function
alloc_swap_slot_cache adding allocation of the extension
of struct swap_slots_cache;
2) android_vh_drain_slots_cache_cpu, replace the function
drain_slots_cache_cpu adding the initialization of the
extension of struct swap_slots_cache;
3) android_vh_get_swap_page, replace the function get_swap_page,
according to the reclaimed location information of the page,
get the the swap page from the specified swap location;
Bug: 234214858
Signed-off-by: Bing Han <bing.han@transsion.com>
Change-Id: I3bce6e8cf255df1d879b7c4022d54981cce7c273
d4eef93a9d