From bb98f2c5ac5db92d34908dbac81a8de7c47c8353 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 7 Jun 2018 17:05:31 -0700 Subject: mm, memcontrol: move swap charge handling into get_swap_page() Patch series "mm, memcontrol: Implement memory.swap.events", v2. This patchset implements memory.swap.events which contains max and fail events so that userland can monitor and respond to swap running out. This patch (of 2): get_swap_page() is always followed by mem_cgroup_try_charge_swap(). This patch moves mem_cgroup_try_charge_swap() into get_swap_page() and makes get_swap_page() call the function even after swap allocation failure. This simplifies the callers and consolidates memcg related logic and will ease adding swap related memcg events. Link: http://lkml.kernel.org/r/20180416230934.GH1911913@devbig577.frc2.facebook.com Signed-off-by: Tejun Heo Reviewed-by: Andrew Morton Cc: Johannes Weiner Cc: Michal Hocko Cc: Vladimir Davydov Cc: Roman Gushchin Cc: Rik van Riel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/swap_slots.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'mm/swap_slots.c') diff --git a/mm/swap_slots.c b/mm/swap_slots.c index f2641894f440..f51ac051c0c9 100644 --- a/mm/swap_slots.c +++ b/mm/swap_slots.c @@ -317,7 +317,7 @@ swp_entry_t get_swap_page(struct page *page) if (PageTransHuge(page)) { if (IS_ENABLED(CONFIG_THP_SWAP)) get_swap_pages(1, true, &entry); - return entry; + goto out; } /* @@ -347,10 +347,14 @@ repeat: } mutex_unlock(&cache->alloc_lock); if (entry.val) - return entry; + goto out; } get_swap_pages(1, false, &entry); - +out: + if (mem_cgroup_try_charge_swap(page, entry)) { + put_swap_page(page, entry); + entry.val = 0; + } return entry; } -- cgit v1.2.3