Messages in this thread | | | Date | Thu, 27 Jan 2005 08:44:33 +1100 | From | Peter Williams <> | Subject | Re: [patch, 2.6.11-rc2] sched: RLIMIT_RT_CPU feature, -D7 |
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Ingo Molnar wrote: > * Peter Williams <pwil3058@bigpond.net.au> wrote: > > >>Oops, after rereading the patch, a task that set its RT_CPU_RATIO >>rlimit to zero wouldn't be escaping the mechanism at all. It would be >>suffering maximum throttling. [...] > > > my intention was to let 'limit 0' mean 'old RT semantics' - i.e. 'no RT > CPU time for unprivileged tasks at all', and only privileged tasks may > do it and then they'll get full CPU time with no throttling. > > so in that context your observation highlights another bug, which i > fixed in the -D7 patch available from the usual place: > > http://redhat.com/~mingo/rt-limit-patches/ > > not doing the '0' exception would make it harder to introduce the rlimit > in a compatible fashion. (My current thinking is that the default RT_CPU > rlimit should be 0.)
One solution to this dilemma might be to set a PF_FLAG on a task whenever it gains RT status via this privilege bypass and only apply the limit to tasks that have that flag set.
Peter -- Peter Williams pwil3058@bigpond.net.au
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