linux/arch/powerpc/kernel
Frederic Weisbecker 280f06774a nohz: Separate out irq exit and idle loop dyntick logic
The tick_nohz_stop_sched_tick() function, which tries to delay
the next timer tick as long as possible, can be called from two
places:

- From the idle loop to start the dytick idle mode
- From interrupt exit if we have interrupted the dyntick
idle mode, so that we reprogram the next tick event in
case the irq changed some internal state that requires this
action.

There are only few minor differences between both that
are handled by that function, driven by the ts->inidle
cpu variable and the inidle parameter. The whole guarantees
that we only update the dyntick mode on irq exit if we actually
interrupted the dyntick idle mode, and that we enter in RCU extended
quiescent state from idle loop entry only.

Split this function into:

- tick_nohz_idle_enter(), which sets ts->inidle to 1, enters
dynticks idle mode unconditionally if it can, and enters into RCU
extended quiescent state.

- tick_nohz_irq_exit() which only updates the dynticks idle mode
when ts->inidle is set (ie: if tick_nohz_idle_enter() has been called).

To maintain symmetry, tick_nohz_restart_sched_tick() has been renamed
into tick_nohz_idle_exit().

This simplifies the code and micro-optimize the irq exit path (no need
for local_irq_save there). This also prepares for the split between
dynticks and rcu extended quiescent state logics. We'll need this split to
further fix illegal uses of RCU in extended quiescent states in the idle
loop.

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>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-12-11 10:31:35 -08:00
..
vdso32 Fix common misspellings 2011-03-31 11:26:23 -03:00
vdso64 Fix common misspellings 2011-03-31 11:26:23 -03:00
.gitignore
align.c
asm-offsets.c Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2011-11-06 17:12:03 -08:00
audit.c
btext.c powerpc: various straight conversions from module.h --> export.h 2011-10-31 19:30:44 -04:00
cacheinfo.c
cacheinfo.h
clock.c powerpc: various straight conversions from module.h --> export.h 2011-10-31 19:30:44 -04:00
compat_audit.c
cpu_setup_6xx.S powerpc: Fix some 6xx/7xxx CPU setup functions 2011-02-07 12:57:11 +11:00
cpu_setup_44x.S
cpu_setup_a2.S powerpc: Add A2 cpu support 2011-04-27 13:02:02 +10:00
cpu_setup_fsl_booke.S powerpc/e5500: set non-base IVORs 2011-05-19 00:36:43 -05:00
cpu_setup_pa6t.S
cpu_setup_power7.S powerpc, KVM: Split HVMODE_206 cpu feature bit into separate HV and architecture bits 2011-07-12 13:16:58 +03:00
cpu_setup_ppc970.S powerpc, KVM: Split HVMODE_206 cpu feature bit into separate HV and architecture bits 2011-07-12 13:16:58 +03:00
cputable.c powerpc: various straight conversions from module.h --> export.h 2011-10-31 19:30:44 -04:00
crash_dump.c crash_dump: export is_kdump_kernel to modules, consolidate elfcorehdr_addr, setup_elfcorehdr and saved_max_pfn 2011-03-23 19:47:19 -07:00
crash.c powerpc: add export.h to files making use of EXPORT_SYMBOL 2011-10-31 19:30:37 -04:00
dbell.c powerpc: Consolidate ipi message mux and demux 2011-05-19 15:31:03 +10:00
dma-iommu.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
dma-swiotlb.c powerpc: Use the newly added get_required_mask dma_map_ops hook 2011-09-20 09:19:35 +10:00
dma.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
e500-pmu.c perf, arch: Add generic NODE cache events 2011-07-01 11:06:38 +02:00
entry_32.S powerpc/trace: Add a dummy stack frame for trace_hardirqs_off 2011-11-16 14:47:54 +11:00
entry_64.S powerpc: Free up some CPU feature bits by moving out MMU-related features 2011-04-27 14:18:52 +10:00
exceptions-64e.S powerpc/book3e-64: Reraise doorbell when masked by soft-irq-disable 2011-06-29 16:40:59 +10:00
exceptions-64s.S powerpc/kvm: Fix build failure with HV KVM and CBE 2011-11-08 15:34:04 +11:00
firmware.c powerpc: fix implicit use of cache.h in kernel/firmware.c 2011-10-31 19:30:41 -04:00
fpu.S
fsl_booke_entry_mapping.S
ftrace.c powerpc/ftrace: Implement raw syscall tracepoints on PowerPC 2011-05-26 13:38:57 +10:00
head_8xx.S powerpc/32: Pass device tree address as u64 to machine_init 2011-09-20 09:19:47 +10:00
head_32.S powerpc/32: Pass device tree address as u64 to machine_init 2011-09-20 09:19:47 +10:00
head_40x.S powerpc/32: Pass device tree address as u64 to machine_init 2011-09-20 09:19:47 +10:00
head_44x.S powerpc/32: Pass device tree address as u64 to machine_init 2011-09-20 09:19:47 +10:00
head_64.S powerpc/powernv: Support for OPAL console 2011-09-20 16:09:54 +10:00
head_booke.h powerpc/85xx: Save scratch registers to thread info instead of using SPRGs. 2011-06-22 21:44:55 -05:00
head_fsl_booke.S powerpc/fsl_booke: Fix comment in head_fsl_booke.S 2011-11-03 13:12:28 -05:00
hw_breakpoint.c powerpc: remove non-required uses of include <linux/module.h> 2011-10-31 19:30:44 -04:00
ibmebus.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
idle_6xx.S
idle_book3e.S
idle_e500.S powerpc: e500mc: Fix: use CONFIG_PPC_E500MC in idle_e500.S 2011-10-11 23:23:24 -05:00
idle_power4.S powerpc/pmac/smp: Properly NAP offlined CPU on G5 2011-04-01 15:37:25 +11:00
idle_power7.S KVM: PPC: Allow book3s_hv guests to use SMT processor modes 2011-07-12 13:16:57 +03:00
idle.c nohz: Separate out irq exit and idle loop dyntick logic 2011-12-11 10:31:35 -08:00
init_task.c powerpc: various straight conversions from module.h --> export.h 2011-10-31 19:30:44 -04:00
io-workarounds.c powerpc: io-workarounds.c was implicitly getting init_mm 2011-10-31 19:30:37 -04:00
io.c powerpc: various straight conversions from module.h --> export.h 2011-10-31 19:30:44 -04:00
iomap.c powerpc: include export.h for files using EXPORT_SYMBOL/THIS_MODULE 2011-10-31 19:30:38 -04:00
iommu.c powerpc: Reserve iommu page 0 2011-09-23 10:27:03 +10:00
irq.c powerpc: various straight conversions from module.h --> export.h 2011-10-31 19:30:44 -04:00
isa-bridge.c powerpc: add export.h to files making use of EXPORT_SYMBOL 2011-10-31 19:30:37 -04:00
jump_label.c powerpc: Fix build breakage in jump_label.c 2011-11-16 14:25:19 +11:00
kgdb.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-05-23 09:12:26 -07:00
kprobes.c
kvm_emul.S
kvm.c powerpc: Copy down exception vectors after feature fixups 2011-11-16 14:47:54 +11:00
l2cr_6xx.S Fix common misspellings 2011-03-31 11:26:23 -03:00
legacy_serial.c serial/8250: Move UPIO_TSI to powerpc 2011-09-20 09:19:39 +10:00
lparcfg.c powerpc/pseries: Add page coalescing support 2011-05-04 16:02:21 +10:00
machine_kexec_32.c
machine_kexec_64.c powerpc: Use for_each_node_by_type instead of open coding it 2011-09-20 15:53:23 +10:00
machine_kexec.c powerpc: Move kdump default base address to half RMO size on 64bit 2011-08-05 14:47:56 +10:00
Makefile powerpc: Add jump label support 2011-07-01 13:48:55 +10:00
misc_32.S powerpc/4xx: Fix typos in kexec config dependencies 2011-11-16 14:47:54 +11:00
misc_64.S powerpc/maple: Enable scom access functions on Maple 2011-06-29 17:48:20 +10:00
misc.S
module_32.c modules: make arch's use default loader hooks 2011-07-24 22:06:04 +09:30
module_64.c modules: make arch's use default loader hooks 2011-07-24 22:06:04 +09:30
module.c powerpc: remove non-required uses of include <linux/module.h> 2011-10-31 19:30:44 -04:00
mpc7450-pmu.c Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2011-07-25 22:59:39 -07:00
msi.c
nvram_64.c powerpc/nvram: Generalize code for OS partitions in NVRAM 2011-03-04 18:19:04 +11:00
of_platform.c powerpc: various straight conversions from module.h --> export.h 2011-10-31 19:30:44 -04:00
paca.c powerpc: various straight conversions from module.h --> export.h 2011-10-31 19:30:44 -04:00
pci_32.c powerpc: include export.h for files using EXPORT_SYMBOL/THIS_MODULE 2011-10-31 19:30:38 -04:00
pci_64.c powerpc: add export.h to files making use of EXPORT_SYMBOL 2011-10-31 19:30:37 -04:00
pci_dn.c powerpc: add export.h to files making use of EXPORT_SYMBOL 2011-10-31 19:30:37 -04:00
pci_of_scan.c powerpc: add export.h to files making use of EXPORT_SYMBOL 2011-10-31 19:30:37 -04:00
pci-common.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
perf_callchain.c powerpc/perf: Disable pagefaults during callchain stack read 2011-08-05 14:47:56 +10:00
perf_event_fsl_emb.c perf: Remove the nmi parameter from the swevent and overflow interface 2011-07-01 11:06:35 +02:00
perf_event.c Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2011-07-25 22:59:39 -07:00
pmc.c powerpc: various straight conversions from module.h --> export.h 2011-10-31 19:30:44 -04:00
power4-pmu.c Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2011-07-25 22:59:39 -07:00
power5-pmu.c Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2011-07-25 22:59:39 -07:00
power5+-pmu.c Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2011-07-25 22:59:39 -07:00
power6-pmu.c powerpc/perf_event: Fix Power6 L1 cache read & write event codes] 2011-09-29 17:04:59 +10:00
power7-pmu.c perf events, powerpc: Add POWER7 stalled-cycles-frontend/backend events 2011-09-20 16:12:56 +10:00
ppc32.h
ppc970-pmu.c Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2011-07-25 22:59:39 -07:00
ppc_ksyms.c powerpc: various straight conversions from module.h --> export.h 2011-10-31 19:30:44 -04:00
ppc_save_regs.S Fix common misspellings 2011-03-31 11:26:23 -03:00
proc_powerpc.c
process.c powerpc/book3e-64: Fix debug support for userspace 2011-11-17 16:26:07 +11:00
prom_init_check.sh powerpc/powernv: Get kernel command line accross OPAL takeover 2011-09-20 16:09:48 +10:00
prom_init.c powerpc: panic if we can't instantiate RTAS 2011-11-16 14:47:54 +11:00
prom_parse.c powerpc: remove non-required uses of include <linux/module.h> 2011-10-31 19:30:44 -04:00
prom.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
ptrace32.c
ptrace.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
reloc_64.S
rtas_flash.c notifiers: sys: move reboot notifiers into reboot.h 2011-07-25 20:57:14 -07:00
rtas_pci.c powerpc: rename ppc_pci_*_flags to pci_*_flags 2011-07-12 09:28:04 -05:00
rtas-proc.c
rtas-rtc.c powerpc/rtas-rtc: remove sideeffects of printk_ratelimit 2011-06-29 15:30:43 +10:00
rtas.c powerpc: various straight conversions from module.h --> export.h 2011-10-31 19:30:44 -04:00
rtasd.c atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
setup_32.c powerpc: Copy down exception vectors after feature fixups 2011-11-16 14:47:54 +11:00
setup_64.c powerpc: Copy down exception vectors after feature fixups 2011-11-16 14:47:54 +11:00
setup-common.c powerpc: various straight conversions from module.h --> export.h 2011-10-31 19:30:44 -04:00
setup.h
signal_32.c powerpc/signal32: Fix sigset_t conversion when copying to user 2011-11-17 16:41:10 +11:00
signal_64.c powerpc: remove non-required uses of include <linux/module.h> 2011-10-31 19:30:44 -04:00
signal.c
signal.h
smp-tbsync.c atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
smp.c powerpc/irq: Remove IRQF_DISABLED 2011-11-08 14:51:46 +11:00
softemu8xx.c
stacktrace.c powerpc: various straight conversions from module.h --> export.h 2011-10-31 19:30:44 -04:00
suspend.c
swsusp_32.S Fix common misspellings 2011-03-31 11:26:23 -03:00
swsusp_64.c powerpc: Fix up implicit sched.h users 2011-10-31 19:30:40 -04:00
swsusp_asm64.S
swsusp_booke.S
swsusp.c powerpc/mm: Fix the call trace when resumed from hibernation 2011-09-20 09:19:58 +10:00
sys_ppc32.c
syscalls.c
sysfs.c powerpc: various straight conversions from module.h --> export.h 2011-10-31 19:30:44 -04:00
systbl_chk.c
systbl_chk.sh
systbl.S
tau_6xx.c
time.c powerpc: various straight conversions from module.h --> export.h 2011-10-31 19:30:44 -04:00
traps.c powerpc: Remove extraneous CONFIG_PPC_ADV_DEBUG_REGS define 2011-11-17 16:26:07 +11:00
udbg_16550.c powerpc: Add early debug for WSP platforms 2011-05-06 13:32:41 +10:00
udbg.c Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2011-11-06 17:12:03 -08:00
vdso.c powerpc: remove non-required uses of include <linux/module.h> 2011-10-31 19:30:44 -04:00
vecemu.c
vector.S powerpc: Remove static branch hint in giveup_altivec 2011-05-19 14:30:42 +10:00
vio.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
vmlinux.lds.S percpu: Always align percpu output section to PAGE_SIZE 2011-03-24 18:50:09 +01:00