crash —— 查看当前系统每个page的信息

发布时间 2023-09-24 15:17:51作者: 摩斯电码

linux中page数据结构可以通过mem_map数组访问,下面的方法可以输出每个page的相关成员。

通用版本

下面这个命令可以显示每个page的一些关键成员的值。

crash> kmem -p
      PAGE        PHYSICAL      MAPPING       INDEX CNT FLAGS
ffffea0000000000         0                0        0  1 fffc0000001000 reserved
ffffea0000000040      1000                0        0  1 fffc0000001000 reserved
ffffea0000000080      2000                0        0  1 fffc0000001000 reserved
ffffea00000000c0      3000                0        0  1 fffc0000001000 reserved
ffffea0000000100      4000                0        0  1 fffc0000001000 reserved
ffffea0000000140      5000                0        0  1 fffc0000001000 reserved
ffffea0000000180      6000                0        0  1 fffc0000001000 reserved
ffffea00000001c0      7000                0        0  1 fffc0000001000 reserved
...

定制

除了上面固定输出一些字段,也可以定制输出page的指定字段的值

crash> kmem -m flags,_mapcount,_refcount,lru,index,mapping
      PAGE        flags  _mapcount  _refcount  lru  index  mapping
ffffea0000000000  0000000000000800  0  00000000ffffea0000000008,ffffea0000000008  0  0000000000000000
ffffea0000000040  0000000000000800  -1  00000001ffffea0000000048,ffffea0000000048  0  0000000000000000
ffffea0000000080  0000000000000800  -1  00000001ffffea0000000088,ffffea0000000088  0  0000000000000000
ffffea00000000c0  0000000000000800  -1  00000001ffffea00000000c8,ffffea00000000c8  0  0000000000000000
ffffea0000000100  0000000000000800  -1  00000001ffffea0000000108,ffffea0000000108  0  0000000000000000
ffffea0000000140  0000000000000800  -1  00000001ffffea0000000148,ffffea0000000148  0  0000000000000000
ffffea0000000180  0000000000000800  -1  00000001ffffea0000000188,ffffea0000000188  0  0000000000000000
ffffea00000001c0  0000000000000800  -1  00000001ffffea00000001c8,ffffea00000001c8  0  0000000000000000
ffffea0000000200  0000000000000800  -1  00000001ffffea0000000208,ffffea0000000208  0  0000000000000000
ffffea0000000240  0000000000000800  -1  00000001ffffea0000000248,ffffea0000000248  0  0000000000000000
...