From a14421ae2a99378c4103bb03606465ab13e75509 Mon Sep 17 00:00:00 2001 From: Barry Song Date: Fri, 12 Apr 2024 23:48:58 +1200 Subject: [PATCH] mm: correct the docs for thp_fault_alloc and thp_fault_fallback The documentation does not align with the code. In __do_huge_pmd_anonymous_page(), THP_FAULT_FALLBACK is incremented when mem_cgroup_charge() fails, despite the allocation succeeding, whereas THP_FAULT_ALLOC is only incremented after a successful charge. Link: https://lkml.kernel.org/r/20240412114858.407208-5-21cnbao@gmail.com Signed-off-by: Barry Song Reviewed-by: Ryan Roberts Reviewed-by: David Hildenbrand Cc: Chris Li Cc: Domenico Cerasuolo Cc: Kairui Song Cc: Matthew Wilcox (Oracle) Cc: Peter Xu Cc: Ryan Roberts Cc: Suren Baghdasaryan Cc: Yosry Ahmed Cc: Yu Zhao Cc: Jonathan Corbet Signed-off-by: Andrew Morton --- Documentation/admin-guide/mm/transhuge.rst | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/Documentation/admin-guide/mm/transhuge.rst b/Documentation/admin-guide/mm/transhuge.rst index e0fe17affeb3..f82300b9193f 100644 --- a/Documentation/admin-guide/mm/transhuge.rst +++ b/Documentation/admin-guide/mm/transhuge.rst @@ -369,7 +369,7 @@ monitor how successfully the system is providing huge pages for use. thp_fault_alloc is incremented every time a huge page is successfully - allocated to handle a page fault. + allocated and charged to handle a page fault. thp_collapse_alloc is incremented by khugepaged when it has found @@ -377,7 +377,7 @@ thp_collapse_alloc successfully allocated a new huge page to store the data. thp_fault_fallback - is incremented if a page fault fails to allocate + is incremented if a page fault fails to allocate or charge a huge page and instead falls back to using small pages. thp_fault_fallback_charge