/proc/pid/smaps: export amount of anonymous memory in a mapping
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.
Exporting this count will help gdb to make a better decision on which
areas need to be dumped in its coredump; and should be useful to others
studying the memory usage of a process.
Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Acked-by: Hugh Dickins <hughd@google.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 871e25e..da6b01d 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -327,6 +327,7 @@
unsigned long private_clean;
unsigned long private_dirty;
unsigned long referenced;
+ unsigned long anonymous;
unsigned long swap;
u64 pss;
};
@@ -357,6 +358,9 @@
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))
@@ -410,6 +414,7 @@
"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",
@@ -421,6 +426,7 @@
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);