2bbb6817c0
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, add two new APIs: tick_nohz_idle_enter_norcu() and tick_nohz_idle_exit_norcu(). If no use of RCU is made in the idle loop between tick_nohz_enter_idle() and tick_nohz_exit_idle() calls, the arch must instead call the new *_norcu() version such that the arch doesn't need to call rcu_idle_enter() and rcu_idle_exit(). Otherwise the arch must call tick_nohz_enter_idle() and tick_nohz_exit_idle() and also call explicitly: - rcu_idle_enter() after its last use of RCU before the CPU is put to sleep. - rcu_idle_exit() before the first use of RCU after the CPU is woken up. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: David Miller <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Paul Mackerras <paulus@samba.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> |
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.. | ||
call_hpt.h | ||
call_pci.h | ||
call_sm.h | ||
dt.c | ||
exception.h | ||
exception.S | ||
htab.c | ||
hvcall.S | ||
hvlog.c | ||
hvlpconfig.c | ||
iommu.c | ||
ipl_parms.h | ||
irq.c | ||
irq.h | ||
it_exp_vpd_panel.h | ||
it_lp_naca.h | ||
Kconfig | ||
ksyms.c | ||
lpardata.c | ||
lpevents.c | ||
main_store.h | ||
Makefile | ||
mf.c | ||
misc.S | ||
naca.h | ||
pci.c | ||
pci.h | ||
proc.c | ||
processor_vpd.h | ||
release_data.h | ||
setup.c | ||
setup.h | ||
smp.c | ||
spcomm_area.h | ||
vio.c | ||
viopath.c | ||
vpd_areas.h |