From 5f48f0bd4e368425db4424b9afd1bd251d32367a Mon Sep 17 00:00:00 2001 From: Prakash Gupta Date: Wed, 13 Sep 2017 16:28:35 -0700 Subject: [PATCH] mm, page_owner: skip unnecessary stack_trace entries The page_owner stacktrace always begin as follows: [] save_stack+0x40/0xc8 [] __set_page_owner+0x3c/0x6c These two entries do not provide any useful information and limits the available stacktrace depth. The page_owner stacktrace was skipping caller function from stack entries but this was missed with commit f2ca0b557107 ("mm/page_owner: use stackdepot to store stacktrace") Example page_owner entry after the patch: Page allocated via order 0, mask 0x8(ffffff80085fb714) PFN 654411 type Movable Block 639 type CMA Flags 0x0(ffffffbe5c7f12c0) [] post_alloc_hook+0x70/0x80 ... [] msm_comm_try_state+0x5f8/0x14f4 [] msm_vidc_open+0x5e4/0x7d0 [] msm_v4l2_open+0xa8/0x224 Link: http://lkml.kernel.org/r/1504078343-28754-2-git-send-email-guptap@codeaurora.org Fixes: f2ca0b557107 ("mm/page_owner: use stackdepot to store stacktrace") Signed-off-by: Prakash Gupta Acked-by: Vlastimil Babka Cc: Catalin Marinas Cc: Joonsoo Kim Cc: Michal Hocko Cc: Russell King Cc: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page_owner.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/page_owner.c b/mm/page_owner.c index 8e2d7137510c..57abca62d4db 100644 --- a/mm/page_owner.c +++ b/mm/page_owner.c @@ -142,7 +142,7 @@ static noinline depot_stack_handle_t save_stack(gfp_t flags) .nr_entries = 0, .entries = entries, .max_entries = PAGE_OWNER_STACK_DEPTH, - .skip = 0 + .skip = 2 }; depot_stack_handle_t handle; -- 2.20.1