Re: [Crash-utility] [PATCH v2] Add -m option to kmem
----- Original Message -----
kmem -m|-M is used for displaying information of all ksm pages or
some ksm pages for specified ksm stable tree node addresses
for example:
crash> kmem -m
STABLE_NODE : ffff88083fc927e0
PAGE : ffffea000e667998
PHYSICAL ADDRESS: 41d475000
PID: 2967 MAPPING: 3
STABLE_NODE : ffff88083fc84a10
PAGE : ffffea000e3dd5d8
PHYSICAL ADDRESS: 411aad000
PID: 2967 MAPPING: 7
STABLE_NODE : ffff88041980dda8
PAGE : ffffea000e335568
PHYSICAL ADDRESS: 40eaab000
PID: 2967 MAPPING: 8
...
STABLE_NODE : ffff880841ea43f8
PAGE : ffffea000f62de38
PHYSICAL ADDRESS: 465641000
PID: 2967 MAPPING: 729
PID: 3017 MAPPING: 499
P.S.
This patch is based on the patch from Qiao(qiaonuohan(a)cn.fujitsu.com)
0001-make-rbtree-manipulation-functions-global.patch
Because this patch also uses rb_tree operations.
I cannot test this because all of my sample dumps either return:
crash> kmem -m
kmem: -m option not supported or applicable on this architecture or kernel
crash>
or:
crash> kmem -m
ksm may not be enabled
crash>
which, by the way, is not a very helpful error message.
Do you have a reasonably-sized vmcore that I can download and test?
Also, I have a question about the help message:
crash> help kmem
NAME
kmem - kernel memory
SYNOPSIS
kmem [-f|-F|-p|-c|-C|-i|-s|-S|-v|-V|-n|-z|-o|-m|-M] [slab] [[-P] address]
[-g [flags]
DESCRIPTION
... [ cut ] ...
-m displays information of ksm pages.
-M same as -m, but also dumps virtual addresses that mapping the
ksm pages.
... [ cut ] ...
address when used with -m or -M, the address can be either a ksm stable
tree node address, a page's physical address, or a page pointer,
the information of the ksm page (if it is) is displayed.
... [ cut ] ...
Display information of ksm pages:
crash> kmem -m ffff88086f22eec0 ffff8803573964c0
STABLE_NODE : ffff88083fc927e0
PAGE : ffffea000e667998
PHYSICAL ADDRESS: 41d475000
PID: 2967 MAPPING: 3
STABLE_NODE : ffff88083fc84a10
PAGE : ffffea000e3dd5d8
PHYSICAL ADDRESS: 411aad000
PID: 2967 MAPPING: 7
STABLE_NODE : ffff88041980dda8
PAGE : ffffea000e335568
PHYSICAL ADDRESS: 40eaab000
PID: 2967 MAPPING: 8
......
STABLE_NODE : ffff880841ea43f8
PAGE : ffffea000f62de38
PHYSICAL ADDRESS: 465641000
PID: 2967 MAPPING: 729
PID: 3017 MAPPING: 499
crash>
Please tell me how the two address arguments ffff88086f22eec0 and
ffff8803573964c0 have any relationship to the subsequent display?
Dave