Userspace tool to map virtual page addresses to physical addresses. Based
on the /proc/pid/pagemap interface, described in kernel docs (pagemap.txt):
https://www.kernel.org/doc/Documentation/vm/pagemap.txt

See also linux/tools/vm/page-types.c for a similar tool that generates page
statistics (must be run as root, unlike this tool).

This package includes the following tools:
- pagemap: prints physical pages for a given virtual address range
- pagemap2: parses /proc/pid/maps and shows all virtual->physical mappings
- classify.sh: prints pages in common between multiple processes

Examples follow.


### Example 1: print specific page ranges for a given process

$ cat &
[1] 11405
$ ./pagemap 11405 0x400000 0x406000
0x400000           : pfn c1719            soft-dirty 0 file/shared 1 swapped 0 present 1
0x401000           : pfn c1718            soft-dirty 0 file/shared 1 swapped 0 present 1
0x402000           : pfn c1717            soft-dirty 0 file/shared 1 swapped 0 present 1
0x403000           : pfn c1716            soft-dirty 0 file/shared 1 swapped 0 present 1
0x404000           : pfn c171a            soft-dirty 0 file/shared 1 swapped 0 present 1
0x405000           : pfn c16ef            soft-dirty 0 file/shared 1 swapped 0 present 1


### Example 2: print all pages for given process (using bash variable $$ to find bash's pid)

$ ./pagemap2 $$ | grep '^0x40'
0x400000           : pfn c1719            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/bash
0x401000           : pfn c1718            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/bash
0x402000           : pfn c1717            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/bash
0x403000           : pfn c1716            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/bash
0x404000           : pfn c171a            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/bash
0x405000           : pfn c16ef            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/bash
0x406000           : pfn 0                soft-dirty 0 file/shared 0 swapped 0 present 0 library /bin/bash
0x407000           : pfn c171d            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/bash
0x408000           : pfn 0                soft-dirty 0 file/shared 0 swapped 0 present 0 library /bin/bash
0x409000           : pfn 0                soft-dirty 0 file/shared 0 swapped 0 present 0 library /bin/bash
0x40a000           : pfn c153d            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/bash
0x40b000           : pfn 0                soft-dirty 0 file/shared 0 swapped 0 present 0 library /bin/bash
0x40c000           : pfn 0                soft-dirty 0 file/shared 0 swapped 0 present 0 library /bin/bash
0x40d000           : pfn c16b5            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/bash
0x40e000           : pfn c150a            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/bash
0x40f000           : pfn c1d5a            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/bash


### Example 3: print all pages for multiple processes

$ ./pagemap2 11437 11564 | grep -E '^0x40|==='
=== Maps for pid 11437
0x400000           : pfn c1d6d            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
0x401000           : pfn c1d75            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
0x402000           : pfn c1d76            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
0x403000           : pfn 0                soft-dirty 0 file/shared 0 swapped 0 present 0 library /bin/cat
0x404000           : pfn c1d69            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
0x405000           : pfn c1d53            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
0x406000           : pfn 0                soft-dirty 0 file/shared 0 swapped 0 present 0 library /bin/cat
0x407000           : pfn 0                soft-dirty 0 file/shared 0 swapped 0 present 0 library /bin/cat
0x408000           : pfn c2332            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
0x409000           : pfn c2331            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
0x40a000           : pfn 0                soft-dirty 0 file/shared 0 swapped 0 present 0 library /bin/cat
=== Maps for pid 11564
0x400000           : pfn c1d6d            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
0x401000           : pfn c1d75            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
0x402000           : pfn c1d76            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
0x403000           : pfn 0                soft-dirty 0 file/shared 0 swapped 0 present 0 library /bin/cat
0x404000           : pfn c1d69            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
0x405000           : pfn c1d53            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
0x406000           : pfn 0                soft-dirty 0 file/shared 0 swapped 0 present 0 library /bin/cat
0x407000           : pfn 0                soft-dirty 0 file/shared 0 swapped 0 present 0 library /bin/cat
0x408000           : pfn c2332            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
0x409000           : pfn c2331            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
0x40a000           : pfn 0                soft-dirty 0 file/shared 0 swapped 0 present 0 library /bin/cat


### Example 4: show pages in common between two processes

$ ./classify.sh 11437 11564 | grep cat
c1d53    => 0x405000           : pfn c1d53            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
c1d53    => 0x405000           : pfn c1d53            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
c1d69    => 0x404000           : pfn c1d69            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
c1d69    => 0x404000           : pfn c1d69            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
c1d6d    => 0x400000           : pfn c1d6d            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
c1d6d    => 0x400000           : pfn c1d6d            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
c1d75    => 0x401000           : pfn c1d75            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
c1d75    => 0x401000           : pfn c1d75            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
c1d76    => 0x402000           : pfn c1d76            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
c1d76    => 0x402000           : pfn c1d76            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
c2331    => 0x409000           : pfn c2331            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
c2331    => 0x409000           : pfn c2331            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
c2332    => 0x408000           : pfn c2332            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
c2332    => 0x408000           : pfn c2332            soft-dirty 0 file/shared 1 swapped 0 present 1 library /bin/cat
$ ./classify.sh 11437 11564 | grep libc | head
14da     => 0x7fcddf6a4000     : pfn 14da             soft-dirty 0 file/shared 1 swapped 0 present 1 library /lib/x86_64-linux-gnu/libc-2.19.so
14da     => 0x7f6e9784a000     : pfn 14da             soft-dirty 0 file/shared 1 swapped 0 present 1 library /lib/x86_64-linux-gnu/libc-2.19.so
14db     => 0x7fcddf6a5000     : pfn 14db             soft-dirty 0 file/shared 1 swapped 0 present 1 library /lib/x86_64-linux-gnu/libc-2.19.so
14db     => 0x7f6e9784b000     : pfn 14db             soft-dirty 0 file/shared 1 swapped 0 present 1 library /lib/x86_64-linux-gnu/libc-2.19.so
15c1     => 0x7fcddf766000     : pfn 15c1             soft-dirty 0 file/shared 1 swapped 0 present 1 library /lib/x86_64-linux-gnu/libc-2.19.so
15c1     => 0x7f6e9790c000     : pfn 15c1             soft-dirty 0 file/shared 1 swapped 0 present 1 library /lib/x86_64-linux-gnu/libc-2.19.so
15c2     => 0x7fcddf767000     : pfn 15c2             soft-dirty 0 file/shared 1 swapped 0 present 1 library /lib/x86_64-linux-gnu/libc-2.19.so
15c2     => 0x7f6e9790d000     : pfn 15c2             soft-dirty 0 file/shared 1 swapped 0 present 1 library /lib/x86_64-linux-gnu/libc-2.19.so
15c3     => 0x7fcddf768000     : pfn 15c3             soft-dirty 0 file/shared 1 swapped 0 present 1 library /lib/x86_64-linux-gnu/libc-2.19.so
15c3     => 0x7f6e9790e000     : pfn 15c3             soft-dirty 0 file/shared 1 swapped 0 present 1 library /lib/x86_64-linux-gnu/libc-2.19.so

Here, each pair of lines shows the same physical page mapped into two processes
(the first line is from the first process, the second from the second process).
Note that the virtual address may be the same, as for /bin/cat's code pages, or
different, as for libc mapped to different base addresses.