Messages in this thread | | | From | David Mosberger <> | Date | Tue, 12 Apr 2005 10:15:54 -0700 | Subject | Re: [patch] sched: unlocked context-switches |
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>>>>> On Tue, 12 Apr 2005 08:42:53 +0200, Ingo Molnar <mingo@elte.hu> said:
Ingo> * David Mosberger <davidm@napali.hpl.hp.com> wrote:
>> Now, Ingo says that the order is reversed with his patch, i.e., >> switch_mm() happens after switch_to(). That means flush_tlb_mm() >> may now see a current->active_mm which hasn't really been >> activated yet. That should be OK since it would just mean that >> we'd do an early (and duplicate) activate_context(). While it >> does not give me a warm and fuzzy feeling to have this >> inconsistent state be observable by interrupt-handlers (and, in >> particular, IPI-handlers), I don't see any problem with it off >> hand.
Ingo> thanks for the analysis. I fundamentally dont have any fuzzy Ingo> feeling from having _any_ portion of the context-switch path Ingo> nonatomic, but with more complex hardware it's just not Ingo> possible it seems.
No kidding! ;-)
I _think_ the change is OK. I'll need testing, of course. Sure would be nice to have 2.7.xx...
Thanks,
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