From 3dd98c5c442358c5aefa13e2c91ee9dee32d776e Mon Sep 17 00:00:00 2001 From: Suren Baghdasaryan Date: Thu, 13 Feb 2025 14:46:51 -0800 Subject: [PATCH] mm/debug: print vm_refcnt state when dumping the vma vm_refcnt encodes a number of useful states: - whether vma is attached or detached - the number of current vma readers - presence of a vma writer Let's include it in the vma dump. Link: https://lkml.kernel.org/r/20250213224655.1680278-15-surenb@google.com Signed-off-by: Suren Baghdasaryan Acked-by: Vlastimil Babka Tested-by: Shivank Garg Link: https://lkml.kernel.org/r/5e19ec93-8307-47c2-bb13-3ddf7150624e@amd.com Cc: Christian Brauner Cc: David Hildenbrand Cc: David Howells Cc: Davidlohr Bueso Cc: Hugh Dickins Cc: Jann Horn Cc: Johannes Weiner Cc: Jonathan Corbet Cc: Klara Modin Cc: Liam R. Howlett Cc: Lokesh Gidra Cc: Lorenzo Stoakes Cc: Mateusz Guzik Cc: Matthew Wilcox Cc: Mel Gorman Cc: Michal Hocko Cc: Minchan Kim Cc: Oleg Nesterov Cc: Pasha Tatashin Cc: "Paul E . McKenney" Cc: Peter Xu Cc: Peter Zijlstra (Intel) Cc: Shakeel Butt Cc: Sourav Panda Cc: Wei Yang Cc: Will Deacon Cc: Heiko Carstens Cc: Stephen Rothwell Signed-off-by: Andrew Morton --- mm/debug.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/mm/debug.c b/mm/debug.c index e1282b85a877..2d1bd67d957b 100644 --- a/mm/debug.c +++ b/mm/debug.c @@ -181,11 +181,17 @@ void dump_vma(const struct vm_area_struct *vma) pr_emerg("vma %px start %px end %px mm %px\n" "prot %lx anon_vma %px vm_ops %px\n" "pgoff %lx file %px private_data %px\n" +#ifdef CONFIG_PER_VMA_LOCK + "refcnt %x\n" +#endif "flags: %#lx(%pGv)\n", vma, (void *)vma->vm_start, (void *)vma->vm_end, vma->vm_mm, (unsigned long)pgprot_val(vma->vm_page_prot), vma->anon_vma, vma->vm_ops, vma->vm_pgoff, vma->vm_file, vma->vm_private_data, +#ifdef CONFIG_PER_VMA_LOCK + refcount_read(&vma->vm_refcnt), +#endif vma->vm_flags, &vma->vm_flags); } EXPORT_SYMBOL(dump_vma); -- 2.50.1