Re: [Crash-utility] [PATCH] runq: make tasks in throttled cfs_rqs/rt_rqs displayed

于 2012年10月30日 03:05, Dave Anderson 写道: > > > ----- Original Message ----- > >>> >>> Now, your patch adds signficant complexity to the runq handling >>> code >>> and to its future maintainability. I'm wondering whether your >>> patch >>> can be modified such that the task_group info would only be >>> displayed >>> via a new flag, let's say "runq -g". It seems that there has >>> been >>> considerable churn in the kernel code in this area, and it >>> worries me >>> that this patch will potentially and unnecessarily cause the >>> breakage >>> of the simple display of the queued tasks. >>> >> >> Currently, rt_rq is displayed hierarchically, while the cfs_rq is >> displayed >> like that. So I made the first patch to make tasks in cfs_rq >> displayed >> hierarchically so that we could see which task belongs to which >> cfs_rq >> easily, just like rt_rq. >> >> The second patch is used to display tasks in throttled >> cfs_rqs/rt_rqs. >> To display tasks in throttled cfs_rqs/rt_rqs is easy, but to >> display them >> sorted in the current runqueue is kind of difficult, so the patch2 >> looks >> complex. I think I will implement the patch2 by two ways, one is >> just the fix >> version of the current patch2, the other is to use the new flag >> '-g'. >> You can decide which one to apply. >> >> The attachment is the patch1. > > The latest patch1 seems to test OK, although your change to dump_task_runq_entry() > that removes the leading spaces breaks the output format of "runq -d". But adding > an INDENT(5) to dump_on_rq_tasks() fixes that. > > My suggestion re: a new -g flag would have it applicable to both CFS and RT > run queues (even though the RT groups are currently being shown). I was > thinking that it might be safest to have "runq" (with no argument) to just > display a simple list of tasks, and only show group information with -g. > Are you suggesting that -g would only apply to throttled cfs_rqs/rt_rqs? > nop, '-g' is ok to show all rqs with group information. I rewrote the patch by adding option '-g' to runq and not changing any behaviour of the runq (with no argument). TODO: 1. The help info about the -g option. I still have a suggestion: when we dump cfs_rq, we don't dump it hierarchically, but for the current rt_rq, we dump it hierarchically with group info. So could I make another patch to remove the rt_rq hierarchy, just make it displayed identical with cfs_rq display.(For -g will display group info for both rt_rq and cfs_rq)