Messages in this thread | | | Date | Mon, 6 Jun 2011 16:30:01 -0400 | From | Chris Metcalf <> | Subject | Re: [PATCH 2/4 v2] nohz: Split extended quiescent state handling from nohz switch |
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On 6/5/2011 11:20 PM, Frederic Weisbecker wrote: > It is assumed that rcu won't be used once we switch to tickless > mode and until we restart the tick. However this is not always > true, as in x86-64 where we dereference the idle notifiers after > the tick is stopped. > > To prepare for fixing this, split the tickless mode switching and > RCU extended quiescent state logics. > Make tick_nohz_stop/restart_sched_tick() RCU agnostic but provide > a new pair of APIs tick_nohz_enter/exit_idle() that keep the > old behaviour by handling both the nohz mode and RCU extended > quiescent states, then convert every archs to use these. > > Archs that want to switch to extended QS to some custom points > can do it later by using tick_nohz_stop_sched_tick() and > rcu_enter_nohz() seperately. > > v2: Remove rcu_exit_nohz() from tick_nohz_restart_sched_tick() > > [...] > arch/tile/kernel/process.c | 4 +-
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
-- Chris Metcalf, Tilera Corp. http://www.tilera.com
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