Documentation/controllers/memory.txt is good guide :)
<abstract>
try_to_free_pages(): global reclaim entry point
try_to_free_mem_cgroup_pages(): memcgroup reclaim entry point
do_try_to_free_pages(): common layer
Unfortunately, I don't know your requirement and
memcgroup reclaim shold be mesured.
I hope you explain your purpose and benefit more.
Thanks.
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