A question about toot1/vm/page-type.c

From: zhong jiang
Date: Wed Jul 20 2016 - 10:07:13 EST


Hi, guys

My system have 4G memory. I print the following memssage.
I execute the command (page-types) to obtain all pfn status. I check 784272 pfn about 3063M from page-types ,
but I ought to obtain all pfn status in the whole memory space, is right ? The Memtotal is ~2932M. therefore,
I guess that page-types do not show the reserved pages from the following memssage.


[root@localhost vm]# ./page-types
flags page-count MB symbolic-flags long-symbolic-flags
0x0000000000000000 89366 349 __________________________________________
0x0000000001000000 1 0 ________________________z_________________ zero_page
0x0000000000000008 13 0 ___U______________________________________ uptodate
0x000000000000000c 1 0 __RU______________________________________ referenced,uptodate
0x0000000000000028 44175 172 ___U_l____________________________________ uptodate,lru
0x000000000000002c 39128 152 __RU_l____________________________________ referenced,uptodate,lru
0x0000000000004030 876 3 ____Dl________b___________________________ dirty,lru,swapbacked
0x0000000000004038 21 0 ___UDl________b___________________________ uptodate,dirty,lru,swapbacked
0x000000000000403c 124 0 __RUDl________b___________________________ referenced,uptodate,dirty,lru,swapbacked
0x0000000000000068 303508 1185 ___U_lA___________________________________ uptodate,lru,active
0x000000000000006c 146546 572 __RU_lA___________________________________ referenced,uptodate,lru,active
0x0000000000004078 17 0 ___UDlA_______b___________________________ uptodate,dirty,lru,active,swapbacked
0x000000000000407c 4 0 __RUDlA_______b___________________________ referenced,uptodate,dirty,lru,active,swapbacked
0x0000000000000080 97203 379 _______S__________________________________ slab
0x0000000000000228 433 1 ___U_l___I________________________________ uptodate,lru,reclaim
0x0000000000000268 599 2 ___U_lA__I________________________________ uptodate,lru,active,reclaim
0x0000000000000400 36344 141 __________B_______________________________ buddy
0x0000000000000800 673 2 ___________M______________________________ mmap
0x0000000000000804 1 0 __R________M______________________________ referenced,mmap
0x0000000000000828 67 0 ___U_l_____M______________________________ uptodate,lru,mmap
0x000000000000082c 435 1 __RU_l_____M______________________________ referenced,uptodate,lru,mmap
0x0000000000004838 711 2 ___UDl_____M__b___________________________ uptodate,dirty,lru,mmap,swapbacked
0x000000000000483c 1 0 __RUDl_____M__b___________________________ referenced,uptodate,dirty,lru,mmap,swapbacked
0x0000000000000868 224 0 ___U_lA____M______________________________ uptodate,lru,active,mmap
0x000000000000086c 5062 19 __RU_lA____M______________________________ referenced,uptodate,lru,active,mmap
0x0000000000004878 463 1 ___UDlA____M__b___________________________ uptodate,dirty,lru,active,mmap,swapbacked
0x0000000000005048 38 0 ___U__A_____a_b___________________________ uptodate,active,anonymous,swapbacked
0x0000000000401800 3577 13 ___________Ma_________t___________________ mmap,anonymous,thp
0x0000000000005828 10863 42 ___U_l_____Ma_b___________________________ uptodate,lru,mmap,anonymous,swapbacked
0x0000000000405828 2 0 ___U_l_____Ma_b_______t___________________ uptodate,lru,mmap,anonymous,swapbacked,thp
0x000000000000582c 35 0 __RU_l_____Ma_b___________________________ referenced,uptodate,lru,mmap,anonymous,swapbacked
0x0000000000005838 4 0 ___UDl_____Ma_b___________________________ uptodate,dirty,lru,mmap,anonymous,swapbacked
0x000000000040583c 1 0 __RUDl_____Ma_b_______t___________________ referenced,uptodate,dirty,lru,mmap,anonymous,swapbacked,thp
0x0000000000005848 20 0 ___U__A____Ma_b___________________________ uptodate,active,mmap,anonymous,swapbacked
0x0000000000005868 3716 14 ___U_lA____Ma_b___________________________ uptodate,lru,active,mmap,anonymous,swapbacked
0x0000000000405868 4 0 ___U_lA____Ma_b_______t___________________ uptodate,lru,active,mmap,anonymous,swapbacked,thp
0x000000000000586c 16 0 __RU_lA____Ma_b___________________________ referenced,uptodate,lru,active,mmap,anonymous,swapbacked
total 784272 3063
[root@localhost vm]# cat /proc/meminfo | head -5
MemTotal: 3003168 kB
MemFree: 145228 kB
MemAvailable: 2386420 kB
Buffers: 72 kB
Cached: 2169560 kB
[root@localhost vm]# free -m
total used free shared buff/cache available
Mem: 2932 292 141 8 2498 2330
Swap: 24191 0 24191

In addition , a stupid question that what is the meaning pfn without flag. the page is allocated by alloc_pages and vmalloc
May be the condition.

Thanks