Re: [Crash-utility] [PATCH] Add -m option to kmem

于 2013年03月02日 05:20, Dave Anderson 写道: > > > ----- Original Message ----- >> kmem -m is used for displaying information of all ksm pages or >> some ksm pages for specified ksm stable tree node addresses >> The information includes: >> - physical address of ksm page, >> - pid of tasks using this ksm page, >> - counts of ksm page references for each task >> >> for example: >> crash> kmem -m ffff8803573964c0 >> PID: 15864 16781 >> 793005000: 8713 5584 >> >> ffff8803573964c0 is the address of ksm stable tree node. >> task 15864 has 8713 virtual pages mapping the page with address 793005000. >> task 16781 has 5584 virtual pages mapping the page with address 793005000. >> >> 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'll get to this patch after I get Qiao's patch straightened out and > checked in. > > But a couple quick questions... > > What does "kmem -m" alone look like? Your help page example only > shows the command passing a "ksm stable tree node address". 'kmem -m' will display all the ksm pages.

> How would a user know what one of those addresses would be? From the structure "rmap_item" ? it has a member "head" that points to a ksm stable tree node.

> > And for "kmem -m <address>", what if there are dozens of PIDs that > are mapping the same physical address? Regardless of the size of > the display window, eventually it would get messy if it extends to > more than one line. I try to avoid having commands extend beyond > 80 columns if at all possible. > Hmm. If there are quite many PIDs, can the output be like below? PID: 15864 16781 16782 16783 793005000: 8713 5584 23 23 12222 13333 14444 15555 232 232 334 456 ...