[PATCH] Export amount of anonymous memory in a mapping via smaps

Nikanth Karthikesan
2010-09-16T03:23:43Z

Export the number of anonymous pages in a mapping via smaps.

Even the private pages in a mapping backed by a file, would be marked as
anonymous, when they are modified. Export this information to user-space via
smaps.

Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>

---

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 439fc1f..3c18fc8 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -326,6 +326,7 @@ struct mem_size_stats {
unsigned long private_clean;
unsigned long private_dirty;
unsigned long referenced;
+ unsigned long anonymous;
unsigned long swap;
u64 pss;
};
@@ -356,6 +357,9 @@ static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
if (!page)
continue;

+ if (PageAnon(page))
+ mss->anonymous += PAGE_SIZE;
+
mss->resident += PAGE_SIZE;
/* Accumulate the size in pages that have been accessed. */
if (pte_young(ptent) || PageReferenced(page))
@@ -409,6 +413,7 @@ static int show_smap(struct seq_file *m, void *v)
"Private_Clean: %8lu kB\n"
"Private_Dirty: %8lu kB\n"
"Referenced: %8lu kB\n"
+ "Anonymous: %8lu kB\n"
"Swap: %8lu kB\n"
"KernelPageSize: %8lu kB\n"
"MMUPageSize: %8lu kB\n",
@@ -420,6 +425,7 @@ static int show_smap(struct seq_file *m, void *v)
mss.private_clean >> 10,
mss.private_dirty >> 10,
mss.referenced >> 10,
+ mss.anonymous >> 10,
mss.swap >> 10,
vma_kernel_pagesize(vma) >> 10,
vma_mmu_pagesize(vma) >> 10);