What:		/proc/pid/smaps_rollup
Date:		August 2017
Contact:	Daniel Colascione <dancol@google.com>
Description:
		This file provides pre-summed memory information for a
		process.  The format is almost identical to /proc/pid/smaps,
		except instead of an entry for each VMA in a process,
		smaps_rollup has a single entry (tagged "[rollup]")
		for which each field is the sum of the corresponding
		fields from all the maps in /proc/pid/smaps.
		Additionally, the fields Pss_Anon, Pss_File and Pss_Shmem
		are not present in /proc/pid/smaps.  These fields represent
		the sum of the Pss field of each type (anon, file, shmem).
		For more details, see Documentation/filesystems/proc.rst
		and the procfs man page.

		Typical output looks like this::

			00100000-ff709000 ---p 00000000 00:00 0		 [rollup]
			Size:               1192 kB
			KernelPageSize:        4 kB
			MMUPageSize:           4 kB
			Rss:		     884 kB
			Pss:		     385 kB
			Pss_Anon:	     301 kB
			Pss_File:	      80 kB
			Pss_Shmem:	       4 kB
			Shared_Clean:	     696 kB
			Shared_Dirty:	       0 kB
			Private_Clean:	     120 kB
			Private_Dirty:	      68 kB
			Referenced:	     884 kB
			Anonymous:	      68 kB
			LazyFree:	       0 kB
			AnonHugePages:	       0 kB
			ShmemPmdMapped:	       0 kB
			Shared_Hugetlb:	       0 kB
			Private_Hugetlb:       0 kB
			Swap:		       0 kB
			SwapPss:	       0 kB
			Locked:		     385 kB