From bca15543736f9be6d84e0bbc262ea7069076b9e6 Mon Sep 17 00:00:00 2001 From: Konstantin Khlebnikov Date: Thu, 31 May 2012 16:26:20 -0700 Subject: [PATCH] proc/smaps: show amount of nonlinear ptes in vma Currently, nonlinear mappings can not be distinguished from ordinary mappings. This patch adds into /proc/pid/smaps line "Nonlinear: kB", where size is amount of nonlinear ptes in vma, this line appears only if VM_NONLINEAR is set. This information may be useful not only for checkpoint/restore project. Requested by Pavel Emelyanov. Signed-off-by: Konstantin Khlebnikov Cc: Andi Kleen Cc: Pavel Emelyanov Cc: Alexey Dobriyan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/proc/task_mmu.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index e2c1155ac09a..4540b8f76f16 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -393,6 +393,7 @@ struct mem_size_stats { unsigned long anonymous; unsigned long anonymous_thp; unsigned long swap; + unsigned long nonlinear; u64 pss; }; @@ -402,6 +403,7 @@ static void smaps_pte_entry(pte_t ptent, unsigned long addr, { struct mem_size_stats *mss = walk->private; struct vm_area_struct *vma = mss->vma; + pgoff_t pgoff = linear_page_index(vma, addr); struct page *page = NULL; int mapcount; @@ -414,6 +416,9 @@ static void smaps_pte_entry(pte_t ptent, unsigned long addr, mss->swap += ptent_size; else if (is_migration_entry(swpent)) page = migration_entry_to_page(swpent); + } else if (pte_file(ptent)) { + if (pte_to_pgoff(ptent) != pgoff) + mss->nonlinear += ptent_size; } if (!page) @@ -422,6 +427,9 @@ static void smaps_pte_entry(pte_t ptent, unsigned long addr, if (PageAnon(page)) mss->anonymous += ptent_size; + if (page->index != pgoff) + mss->nonlinear += ptent_size; + mss->resident += ptent_size; /* Accumulate the size in pages that have been accessed. */ if (pte_young(ptent) || PageReferenced(page)) @@ -523,6 +531,10 @@ static int show_smap(struct seq_file *m, void *v, int is_pid) (vma->vm_flags & VM_LOCKED) ? (unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0); + if (vma->vm_flags & VM_NONLINEAR) + seq_printf(m, "Nonlinear: %8lu kB\n", + mss.nonlinear >> 10); + if (m->count < m->size) /* vma is copied successfully */ m->version = (vma != get_gate_vma(task->mm)) ? vma->vm_start : 0; -- 2.34.1