From 97105f0ab7b877a8ece2005e214894e93793950c Mon Sep 17 00:00:00 2001 From: Roman Gushchin Date: Thu, 11 Jul 2019 21:00:13 -0700 Subject: mm: vmalloc: show number of vmalloc pages in /proc/meminfo Vmalloc() is getting more and more used these days (kernel stacks, bpf and percpu allocator are new top users), and the total % of memory consumed by vmalloc() can be pretty significant and changes dynamically. /proc/meminfo is the best place to display this information: its top goal is to show top consumers of the memory. Since the VmallocUsed field in /proc/meminfo is not in use for quite a long time (it has been defined to 0 by a5ad88ce8c7f ("mm: get rid of 'vmalloc_info' from /proc/meminfo")), let's reuse it for showing the actual physical memory consumption of vmalloc(). Link: http://lkml.kernel.org/r/20190417194002.12369-3-guro@fb.com Signed-off-by: Roman Gushchin Acked-by: Johannes Weiner Acked-by: Vlastimil Babka Reviewed-by: Andrew Morton Cc: Matthew Wilcox Cc: Minchan Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/vmalloc.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'mm/vmalloc.c') diff --git a/mm/vmalloc.c b/mm/vmalloc.c index edb212298c8a..4fa8d84599b0 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -406,6 +406,13 @@ static void purge_vmap_area_lazy(void); static BLOCKING_NOTIFIER_HEAD(vmap_notify_list); static unsigned long lazy_max_pages(void); +static atomic_long_t nr_vmalloc_pages; + +unsigned long vmalloc_nr_pages(void) +{ + return atomic_long_read(&nr_vmalloc_pages); +} + static struct vmap_area *__find_vmap_area(unsigned long addr) { struct rb_node *n = vmap_area_root.rb_node; @@ -2237,6 +2244,7 @@ static void __vunmap(const void *addr, int deallocate_pages) BUG_ON(!page); __free_pages(page, 0); } + atomic_long_sub(area->nr_pages, &nr_vmalloc_pages); kvfree(area->pages); } @@ -2414,12 +2422,14 @@ static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask, if (unlikely(!page)) { /* Successfully allocated i pages, free them in __vunmap() */ area->nr_pages = i; + atomic_long_add(area->nr_pages, &nr_vmalloc_pages); goto fail; } area->pages[i] = page; if (gfpflags_allow_blocking(gfp_mask|highmem_mask)) cond_resched(); } + atomic_long_add(area->nr_pages, &nr_vmalloc_pages); if (map_vm_area(area, prot, pages)) goto fail; -- cgit v1.2.3