From 280f06774afedf849f0b34248ed6aff57d0f6908 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Fri, 7 Oct 2011 18:22:06 +0200 Subject: 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 Cc: Mike Frysinger Cc: Guan Xuetao Cc: David Miller Cc: Chris Metcalf Cc: Hans-Christian Egtvedt Cc: Ralf Baechle Cc: Paul E. McKenney Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: H. Peter Anvin Cc: Russell King Cc: Paul Mackerras Cc: Heiko Carstens Cc: Paul Mundt Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- arch/arm/kernel/process.c | 4 ++-- arch/avr32/kernel/process.c | 4 ++-- arch/blackfin/kernel/process.c | 4 ++-- arch/microblaze/kernel/process.c | 4 ++-- arch/mips/kernel/process.c | 4 ++-- arch/openrisc/kernel/idle.c | 4 ++-- arch/powerpc/kernel/idle.c | 4 ++-- arch/powerpc/platforms/iseries/setup.c | 8 ++++---- arch/s390/kernel/process.c | 4 ++-- arch/sh/kernel/idle.c | 4 ++-- arch/sparc/kernel/process_64.c | 4 ++-- arch/tile/kernel/process.c | 4 ++-- arch/um/kernel/process.c | 4 ++-- arch/unicore32/kernel/process.c | 4 ++-- arch/x86/kernel/process_32.c | 4 ++-- arch/x86/kernel/process_64.c | 4 ++-- 16 files changed, 34 insertions(+), 34 deletions(-) (limited to 'arch') diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 3d0c6fb74ae..3f1f8daf703 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -183,7 +183,7 @@ void cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_stop_sched_tick(1); + tick_nohz_idle_enter(); leds_event(led_idle_start); while (!need_resched()) { #ifdef CONFIG_HOTPLUG_CPU @@ -213,7 +213,7 @@ void cpu_idle(void) } } leds_event(led_idle_end); - tick_nohz_restart_sched_tick(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/avr32/kernel/process.c b/arch/avr32/kernel/process.c index ef5a2a08fcc..6ee7952248d 100644 --- a/arch/avr32/kernel/process.c +++ b/arch/avr32/kernel/process.c @@ -34,10 +34,10 @@ void cpu_idle(void) { /* endless idle loop with no priority at all */ while (1) { - tick_nohz_stop_sched_tick(1); + tick_nohz_idle_enter(); while (!need_resched()) cpu_idle_sleep(); - tick_nohz_restart_sched_tick(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/blackfin/kernel/process.c b/arch/blackfin/kernel/process.c index 6a80a9e9fc4..7b141b5c9e8 100644 --- a/arch/blackfin/kernel/process.c +++ b/arch/blackfin/kernel/process.c @@ -88,10 +88,10 @@ void cpu_idle(void) #endif if (!idle) idle = default_idle; - tick_nohz_stop_sched_tick(1); + tick_nohz_idle_enter(); while (!need_resched()) idle(); - tick_nohz_restart_sched_tick(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/microblaze/kernel/process.c b/arch/microblaze/kernel/process.c index 95cc295976a..5407f09b4be 100644 --- a/arch/microblaze/kernel/process.c +++ b/arch/microblaze/kernel/process.c @@ -103,10 +103,10 @@ void cpu_idle(void) if (!idle) idle = default_idle; - tick_nohz_stop_sched_tick(1); + tick_nohz_idle_enter(); while (!need_resched()) idle(); - tick_nohz_restart_sched_tick(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c index c47f96e453c..c11e5ca2a43 100644 --- a/arch/mips/kernel/process.c +++ b/arch/mips/kernel/process.c @@ -56,7 +56,7 @@ void __noreturn cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_stop_sched_tick(1); + tick_nohz_idle_enter(); while (!need_resched() && cpu_online(cpu)) { #ifdef CONFIG_MIPS_MT_SMTC extern void smtc_idle_loop_hook(void); @@ -77,7 +77,7 @@ void __noreturn cpu_idle(void) system_state == SYSTEM_BOOTING)) play_dead(); #endif - tick_nohz_restart_sched_tick(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/openrisc/kernel/idle.c b/arch/openrisc/kernel/idle.c index d5bc5f813e8..fb6a9bf4000 100644 --- a/arch/openrisc/kernel/idle.c +++ b/arch/openrisc/kernel/idle.c @@ -51,7 +51,7 @@ void cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_stop_sched_tick(1); + tick_nohz_idle_enter(); while (!need_resched()) { check_pgt_cache(); @@ -69,7 +69,7 @@ void cpu_idle(void) set_thread_flag(TIF_POLLING_NRFLAG); } - tick_nohz_restart_sched_tick(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/powerpc/kernel/idle.c b/arch/powerpc/kernel/idle.c index 39a2baa6ad5..878572f70ac 100644 --- a/arch/powerpc/kernel/idle.c +++ b/arch/powerpc/kernel/idle.c @@ -56,7 +56,7 @@ void cpu_idle(void) set_thread_flag(TIF_POLLING_NRFLAG); while (1) { - tick_nohz_stop_sched_tick(1); + tick_nohz_idle_enter(); while (!need_resched() && !cpu_should_die()) { ppc64_runlatch_off(); @@ -93,7 +93,7 @@ void cpu_idle(void) HMT_medium(); ppc64_runlatch_on(); - tick_nohz_restart_sched_tick(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); if (cpu_should_die()) cpu_die(); diff --git a/arch/powerpc/platforms/iseries/setup.c b/arch/powerpc/platforms/iseries/setup.c index ea0acbd8966..e83dfaf89f6 100644 --- a/arch/powerpc/platforms/iseries/setup.c +++ b/arch/powerpc/platforms/iseries/setup.c @@ -563,7 +563,7 @@ static void yield_shared_processor(void) static void iseries_shared_idle(void) { while (1) { - tick_nohz_stop_sched_tick(1); + tick_nohz_idle_enter(); while (!need_resched() && !hvlpevent_is_pending()) { local_irq_disable(); ppc64_runlatch_off(); @@ -577,7 +577,7 @@ static void iseries_shared_idle(void) } ppc64_runlatch_on(); - tick_nohz_restart_sched_tick(); + tick_nohz_idle_exit(); if (hvlpevent_is_pending()) process_iSeries_events(); @@ -593,7 +593,7 @@ static void iseries_dedicated_idle(void) set_thread_flag(TIF_POLLING_NRFLAG); while (1) { - tick_nohz_stop_sched_tick(1); + tick_nohz_idle_enter(); if (!need_resched()) { while (!need_resched()) { ppc64_runlatch_off(); @@ -610,7 +610,7 @@ static void iseries_dedicated_idle(void) } ppc64_runlatch_on(); - tick_nohz_restart_sched_tick(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c index 9451b210a1b..6224f9dbbc1 100644 --- a/arch/s390/kernel/process.c +++ b/arch/s390/kernel/process.c @@ -91,10 +91,10 @@ static void default_idle(void) void cpu_idle(void) { for (;;) { - tick_nohz_stop_sched_tick(1); + tick_nohz_idle_enter(); while (!need_resched()) default_idle(); - tick_nohz_restart_sched_tick(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/sh/kernel/idle.c b/arch/sh/kernel/idle.c index db4ecd731a0..6015743020a 100644 --- a/arch/sh/kernel/idle.c +++ b/arch/sh/kernel/idle.c @@ -89,7 +89,7 @@ void cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_stop_sched_tick(1); + tick_nohz_idle_enter(); while (!need_resched()) { check_pgt_cache(); @@ -111,7 +111,7 @@ void cpu_idle(void) start_critical_timings(); } - tick_nohz_restart_sched_tick(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/sparc/kernel/process_64.c b/arch/sparc/kernel/process_64.c index 3739a06a76c..9c2795ba2cf 100644 --- a/arch/sparc/kernel/process_64.c +++ b/arch/sparc/kernel/process_64.c @@ -95,12 +95,12 @@ void cpu_idle(void) set_thread_flag(TIF_POLLING_NRFLAG); while(1) { - tick_nohz_stop_sched_tick(1); + tick_nohz_idle_enter(); while (!need_resched() && !cpu_is_offline(cpu)) sparc64_yield(cpu); - tick_nohz_restart_sched_tick(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); diff --git a/arch/tile/kernel/process.c b/arch/tile/kernel/process.c index 9c45d8bbdf5..920e674aedb 100644 --- a/arch/tile/kernel/process.c +++ b/arch/tile/kernel/process.c @@ -85,7 +85,7 @@ void cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_stop_sched_tick(1); + tick_nohz_idle_enter(); while (!need_resched()) { if (cpu_is_offline(cpu)) BUG(); /* no HOTPLUG_CPU */ @@ -105,7 +105,7 @@ void cpu_idle(void) local_irq_enable(); current_thread_info()->status |= TS_POLLING; } - tick_nohz_restart_sched_tick(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c index c5338351aec..cfb657e9284 100644 --- a/arch/um/kernel/process.c +++ b/arch/um/kernel/process.c @@ -246,10 +246,10 @@ void default_idle(void) if (need_resched()) schedule(); - tick_nohz_stop_sched_tick(1); + tick_nohz_idle_enter(); nsecs = disable_timer(); idle_sleep(nsecs); - tick_nohz_restart_sched_tick(); + tick_nohz_idle_exit(); } } diff --git a/arch/unicore32/kernel/process.c b/arch/unicore32/kernel/process.c index ba401df971e..9999b9a84d4 100644 --- a/arch/unicore32/kernel/process.c +++ b/arch/unicore32/kernel/process.c @@ -55,7 +55,7 @@ void cpu_idle(void) { /* endless idle loop with no priority at all */ while (1) { - tick_nohz_stop_sched_tick(1); + tick_nohz_idle_enter(); while (!need_resched()) { local_irq_disable(); stop_critical_timings(); @@ -63,7 +63,7 @@ void cpu_idle(void) local_irq_enable(); start_critical_timings(); } - tick_nohz_restart_sched_tick(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index 795b79f984c..6d9d4d52cac 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -99,7 +99,7 @@ void cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_stop_sched_tick(1); + tick_nohz_idle_enter(); while (!need_resched()) { check_pgt_cache(); @@ -116,7 +116,7 @@ void cpu_idle(void) pm_idle(); start_critical_timings(); } - tick_nohz_restart_sched_tick(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 3bd7e6eebf3..b069e9d7875 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -122,7 +122,7 @@ void cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_stop_sched_tick(1); + tick_nohz_idle_enter(); while (!need_resched()) { rmb(); @@ -149,7 +149,7 @@ void cpu_idle(void) __exit_idle(); } - tick_nohz_restart_sched_tick(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); -- cgit v1.2.3 From 2bbb6817c0ac1b5f2a68d720f364f98eeb1ac4fd Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Sat, 8 Oct 2011 16:01:00 +0200 Subject: nohz: Allow rcu extended quiescent state handling seperately from tick stop 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 Cc: Mike Frysinger Cc: Guan Xuetao Cc: David Miller Cc: Chris Metcalf Cc: Hans-Christian Egtvedt Cc: Ralf Baechle Cc: Paul E. McKenney Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: H. Peter Anvin Cc: Russell King Cc: Paul Mackerras Cc: Heiko Carstens Cc: Paul Mundt Signed-off-by: Paul E. McKenney --- arch/arm/kernel/process.c | 4 ++-- arch/avr32/kernel/process.c | 4 ++-- arch/blackfin/kernel/process.c | 4 ++-- arch/microblaze/kernel/process.c | 4 ++-- arch/mips/kernel/process.c | 4 ++-- arch/openrisc/kernel/idle.c | 4 ++-- arch/powerpc/kernel/idle.c | 4 ++-- arch/powerpc/platforms/iseries/setup.c | 8 ++++---- arch/s390/kernel/process.c | 4 ++-- arch/sh/kernel/idle.c | 4 ++-- arch/sparc/kernel/process_64.c | 4 ++-- arch/tile/kernel/process.c | 4 ++-- arch/um/kernel/process.c | 4 ++-- arch/unicore32/kernel/process.c | 4 ++-- arch/x86/kernel/process_32.c | 4 ++-- arch/x86/kernel/process_64.c | 4 ++-- 16 files changed, 34 insertions(+), 34 deletions(-) (limited to 'arch') diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 3f1f8daf703..47e34c09127 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -183,7 +183,7 @@ void cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_idle_enter(); + tick_nohz_idle_enter_norcu(); leds_event(led_idle_start); while (!need_resched()) { #ifdef CONFIG_HOTPLUG_CPU @@ -213,7 +213,7 @@ void cpu_idle(void) } } leds_event(led_idle_end); - tick_nohz_idle_exit(); + tick_nohz_idle_exit_norcu(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/avr32/kernel/process.c b/arch/avr32/kernel/process.c index 6ee7952248d..34c8c703bb1 100644 --- a/arch/avr32/kernel/process.c +++ b/arch/avr32/kernel/process.c @@ -34,10 +34,10 @@ void cpu_idle(void) { /* endless idle loop with no priority at all */ while (1) { - tick_nohz_idle_enter(); + tick_nohz_idle_enter_norcu(); while (!need_resched()) cpu_idle_sleep(); - tick_nohz_idle_exit(); + tick_nohz_idle_exit_norcu(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/blackfin/kernel/process.c b/arch/blackfin/kernel/process.c index 7b141b5c9e8..57e07498a0e 100644 --- a/arch/blackfin/kernel/process.c +++ b/arch/blackfin/kernel/process.c @@ -88,10 +88,10 @@ void cpu_idle(void) #endif if (!idle) idle = default_idle; - tick_nohz_idle_enter(); + tick_nohz_idle_enter_norcu(); while (!need_resched()) idle(); - tick_nohz_idle_exit(); + tick_nohz_idle_exit_norcu(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/microblaze/kernel/process.c b/arch/microblaze/kernel/process.c index 5407f09b4be..13d59f34b94 100644 --- a/arch/microblaze/kernel/process.c +++ b/arch/microblaze/kernel/process.c @@ -103,10 +103,10 @@ void cpu_idle(void) if (!idle) idle = default_idle; - tick_nohz_idle_enter(); + tick_nohz_idle_enter_norcu(); while (!need_resched()) idle(); - tick_nohz_idle_exit(); + tick_nohz_idle_exit_norcu(); preempt_enable_no_resched(); schedule(); diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c index c11e5ca2a43..17fb3a27016 100644 --- a/arch/mips/kernel/process.c +++ b/arch/mips/kernel/process.c @@ -56,7 +56,7 @@ void __noreturn cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_idle_enter(); + tick_nohz_idle_enter_norcu(); while (!need_resched() && cpu_online(cpu)) { #ifdef CONFIG_MIPS_MT_SMTC extern void smtc_idle_loop_hook(void); @@ -77,7 +77,7 @@ void __noreturn cpu_idle(void) system_state == SYSTEM_BOOTING)) play_dead(); #endif - tick_nohz_idle_exit(); + tick_nohz_idle_exit_norcu(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/openrisc/kernel/idle.c b/arch/openrisc/kernel/idle.c index fb6a9bf4000..2e82cd0fa5e 100644 --- a/arch/openrisc/kernel/idle.c +++ b/arch/openrisc/kernel/idle.c @@ -51,7 +51,7 @@ void cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_idle_enter(); + tick_nohz_idle_enter_norcu(); while (!need_resched()) { check_pgt_cache(); @@ -69,7 +69,7 @@ void cpu_idle(void) set_thread_flag(TIF_POLLING_NRFLAG); } - tick_nohz_idle_exit(); + tick_nohz_idle_exit_norcu(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/powerpc/kernel/idle.c b/arch/powerpc/kernel/idle.c index 878572f70ac..2e782a36d8f 100644 --- a/arch/powerpc/kernel/idle.c +++ b/arch/powerpc/kernel/idle.c @@ -56,7 +56,7 @@ void cpu_idle(void) set_thread_flag(TIF_POLLING_NRFLAG); while (1) { - tick_nohz_idle_enter(); + tick_nohz_idle_enter_norcu(); while (!need_resched() && !cpu_should_die()) { ppc64_runlatch_off(); @@ -93,7 +93,7 @@ void cpu_idle(void) HMT_medium(); ppc64_runlatch_on(); - tick_nohz_idle_exit(); + tick_nohz_idle_exit_norcu(); preempt_enable_no_resched(); if (cpu_should_die()) cpu_die(); diff --git a/arch/powerpc/platforms/iseries/setup.c b/arch/powerpc/platforms/iseries/setup.c index e83dfaf89f6..d69d3d185e8 100644 --- a/arch/powerpc/platforms/iseries/setup.c +++ b/arch/powerpc/platforms/iseries/setup.c @@ -563,7 +563,7 @@ static void yield_shared_processor(void) static void iseries_shared_idle(void) { while (1) { - tick_nohz_idle_enter(); + tick_nohz_idle_enter_norcu(); while (!need_resched() && !hvlpevent_is_pending()) { local_irq_disable(); ppc64_runlatch_off(); @@ -577,7 +577,7 @@ static void iseries_shared_idle(void) } ppc64_runlatch_on(); - tick_nohz_idle_exit(); + tick_nohz_idle_exit_norcu(); if (hvlpevent_is_pending()) process_iSeries_events(); @@ -593,7 +593,7 @@ static void iseries_dedicated_idle(void) set_thread_flag(TIF_POLLING_NRFLAG); while (1) { - tick_nohz_idle_enter(); + tick_nohz_idle_enter_norcu(); if (!need_resched()) { while (!need_resched()) { ppc64_runlatch_off(); @@ -610,7 +610,7 @@ static void iseries_dedicated_idle(void) } ppc64_runlatch_on(); - tick_nohz_idle_exit(); + tick_nohz_idle_exit_norcu(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c index 6224f9dbbc1..6fa987367ae 100644 --- a/arch/s390/kernel/process.c +++ b/arch/s390/kernel/process.c @@ -91,10 +91,10 @@ static void default_idle(void) void cpu_idle(void) { for (;;) { - tick_nohz_idle_enter(); + tick_nohz_idle_enter_norcu(); while (!need_resched()) default_idle(); - tick_nohz_idle_exit(); + tick_nohz_idle_exit_norcu(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/sh/kernel/idle.c b/arch/sh/kernel/idle.c index 6015743020a..ad58e7535a7 100644 --- a/arch/sh/kernel/idle.c +++ b/arch/sh/kernel/idle.c @@ -89,7 +89,7 @@ void cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_idle_enter(); + tick_nohz_idle_enter_norcu(); while (!need_resched()) { check_pgt_cache(); @@ -111,7 +111,7 @@ void cpu_idle(void) start_critical_timings(); } - tick_nohz_idle_exit(); + tick_nohz_idle_exit_norcu(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/sparc/kernel/process_64.c b/arch/sparc/kernel/process_64.c index 9c2795ba2cf..4a0e7d79cb9 100644 --- a/arch/sparc/kernel/process_64.c +++ b/arch/sparc/kernel/process_64.c @@ -95,12 +95,12 @@ void cpu_idle(void) set_thread_flag(TIF_POLLING_NRFLAG); while(1) { - tick_nohz_idle_enter(); + tick_nohz_idle_enter_norcu(); while (!need_resched() && !cpu_is_offline(cpu)) sparc64_yield(cpu); - tick_nohz_idle_exit(); + tick_nohz_idle_exit_norcu(); preempt_enable_no_resched(); diff --git a/arch/tile/kernel/process.c b/arch/tile/kernel/process.c index 920e674aedb..53ac89595ab 100644 --- a/arch/tile/kernel/process.c +++ b/arch/tile/kernel/process.c @@ -85,7 +85,7 @@ void cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_idle_enter(); + tick_nohz_idle_enter_norcu(); while (!need_resched()) { if (cpu_is_offline(cpu)) BUG(); /* no HOTPLUG_CPU */ @@ -105,7 +105,7 @@ void cpu_idle(void) local_irq_enable(); current_thread_info()->status |= TS_POLLING; } - tick_nohz_idle_exit(); + tick_nohz_idle_exit_norcu(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c index cfb657e9284..55d2cf455f6 100644 --- a/arch/um/kernel/process.c +++ b/arch/um/kernel/process.c @@ -246,10 +246,10 @@ void default_idle(void) if (need_resched()) schedule(); - tick_nohz_idle_enter(); + tick_nohz_idle_enter_norcu(); nsecs = disable_timer(); idle_sleep(nsecs); - tick_nohz_idle_exit(); + tick_nohz_idle_exit_norcu(); } } diff --git a/arch/unicore32/kernel/process.c b/arch/unicore32/kernel/process.c index 9999b9a84d4..095ff5a5792 100644 --- a/arch/unicore32/kernel/process.c +++ b/arch/unicore32/kernel/process.c @@ -55,7 +55,7 @@ void cpu_idle(void) { /* endless idle loop with no priority at all */ while (1) { - tick_nohz_idle_enter(); + tick_nohz_idle_enter_norcu(); while (!need_resched()) { local_irq_disable(); stop_critical_timings(); @@ -63,7 +63,7 @@ void cpu_idle(void) local_irq_enable(); start_critical_timings(); } - tick_nohz_idle_exit(); + tick_nohz_idle_exit_norcu(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index 6d9d4d52cac..f94da3920c3 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -99,7 +99,7 @@ void cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_idle_enter(); + tick_nohz_idle_enter_norcu(); while (!need_resched()) { check_pgt_cache(); @@ -116,7 +116,7 @@ void cpu_idle(void) pm_idle(); start_critical_timings(); } - tick_nohz_idle_exit(); + tick_nohz_idle_exit_norcu(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index b069e9d7875..18e8cf3581f 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -122,7 +122,7 @@ void cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_idle_enter(); + tick_nohz_idle_enter_norcu(); while (!need_resched()) { rmb(); @@ -149,7 +149,7 @@ void cpu_idle(void) __exit_idle(); } - tick_nohz_idle_exit(); + tick_nohz_idle_exit_norcu(); preempt_enable_no_resched(); schedule(); preempt_disable(); -- cgit v1.2.3 From e37e112de3ac64032df45c2db0dbe1e8f1af86b4 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Fri, 7 Oct 2011 18:22:08 +0200 Subject: x86: Enter rcu extended qs after idle notifier call The idle notifier, called by enter_idle(), enters into rcu read side critical section but at that time we already switched into the RCU-idle window (rcu_idle_enter() has been called). And it's illegal to use rcu_read_lock() in that state. This results in rcu reporting its bad mood: [ 1.275635] WARNING: at include/linux/rcupdate.h:194 __atomic_notifier_call_chain+0xd2/0x110() [ 1.275635] Hardware name: AMD690VM-FMH [ 1.275635] Modules linked in: [ 1.275635] Pid: 0, comm: swapper Not tainted 3.0.0-rc6+ #252 [ 1.275635] Call Trace: [ 1.275635] [] warn_slowpath_common+0x7a/0xb0 [ 1.275635] [] warn_slowpath_null+0x15/0x20 [ 1.275635] [] __atomic_notifier_call_chain+0xd2/0x110 [ 1.275635] [] atomic_notifier_call_chain+0x11/0x20 [ 1.275635] [] enter_idle+0x20/0x30 [ 1.275635] [] cpu_idle+0xa5/0x110 [ 1.275635] [] rest_init+0xe5/0x140 [ 1.275635] [] ? rest_init+0x48/0x140 [ 1.275635] [] start_kernel+0x3d1/0x3dc [ 1.275635] [] x86_64_start_reservations+0x131/0x135 [ 1.275635] [] x86_64_start_kernel+0xed/0xf4 [ 1.275635] ---[ end trace a22d306b065d4a66 ]--- Fix this by entering rcu extended quiescent state later, just before the CPU goes to sleep. Signed-off-by: Frederic Weisbecker Cc: Paul E. McKenney Cc: Ingo Molnar Cc: Thomas Gleixner Cc: H. Peter Anvin Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- arch/x86/kernel/process_64.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'arch') diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 18e8cf3581f..64e926c89a6 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -122,7 +122,7 @@ void cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_idle_enter_norcu(); + tick_nohz_idle_enter(); while (!need_resched()) { rmb(); @@ -139,8 +139,14 @@ void cpu_idle(void) enter_idle(); /* Don't trace irqs off for idle */ stop_critical_timings(); + + /* enter_idle() needs rcu for notifiers */ + rcu_idle_enter(); + if (cpuidle_idle_call()) pm_idle(); + + rcu_idle_exit(); start_critical_timings(); /* In many cases the interrupt that ended idle @@ -149,7 +155,7 @@ void cpu_idle(void) __exit_idle(); } - tick_nohz_idle_exit_norcu(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); -- cgit v1.2.3 From 98ad1cc14a5c4fd658f9d72c6ba5c86dfd3ce0d5 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Fri, 7 Oct 2011 18:22:09 +0200 Subject: x86: Call idle notifier after irq_enter() Interrupts notify the idle exit state before calling irq_enter(). But the notifier code calls rcu_read_lock() and this is not allowed while rcu is in an extended quiescent state. We need to wait for irq_enter() -> rcu_idle_exit() to be called before doing so otherwise this results in a grumpy RCU: [ 0.099991] WARNING: at include/linux/rcupdate.h:194 __atomic_notifier_call_chain+0xd2/0x110() [ 0.099991] Hardware name: AMD690VM-FMH [ 0.099991] Modules linked in: [ 0.099991] Pid: 0, comm: swapper Not tainted 3.0.0-rc6+ #255 [ 0.099991] Call Trace: [ 0.099991] [] warn_slowpath_common+0x7a/0xb0 [ 0.099991] [] warn_slowpath_null+0x15/0x20 [ 0.099991] [] __atomic_notifier_call_chain+0xd2/0x110 [ 0.099991] [] atomic_notifier_call_chain+0x11/0x20 [ 0.099991] [] exit_idle+0x43/0x50 [ 0.099991] [] smp_apic_timer_interrupt+0x39/0xa0 [ 0.099991] [] apic_timer_interrupt+0x13/0x20 [ 0.099991] [] ? default_idle+0xa7/0x350 [ 0.099991] [] ? default_idle+0xa5/0x350 [ 0.099991] [] amd_e400_idle+0x8b/0x110 [ 0.099991] [] ? rcu_enter_nohz+0x8f/0x160 [ 0.099991] [] cpu_idle+0xb0/0x110 [ 0.099991] [] rest_init+0xe5/0x140 [ 0.099991] [] ? rest_init+0x48/0x140 [ 0.099991] [] start_kernel+0x3d1/0x3dc [ 0.099991] [] x86_64_start_reservations+0x131/0x135 [ 0.099991] [] x86_64_start_kernel+0xed/0xf4 Signed-off-by: Frederic Weisbecker Cc: Paul E. McKenney Cc: Ingo Molnar Cc: Thomas Gleixner Cc: H. Peter Anvin Cc: Andy Henroid Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- arch/x86/kernel/apic/apic.c | 6 +++--- arch/x86/kernel/apic/io_apic.c | 2 +- arch/x86/kernel/cpu/mcheck/therm_throt.c | 2 +- arch/x86/kernel/cpu/mcheck/threshold.c | 2 +- arch/x86/kernel/irq.c | 6 +++--- 5 files changed, 9 insertions(+), 9 deletions(-) (limited to 'arch') diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c index f98d84caf94..2cd2d93643d 100644 --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -876,8 +876,8 @@ void __irq_entry smp_apic_timer_interrupt(struct pt_regs *regs) * Besides, if we don't timer interrupts ignore the global * interrupt lock, which is the WrongThing (tm) to do. */ - exit_idle(); irq_enter(); + exit_idle(); local_apic_timer_interrupt(); irq_exit(); @@ -1809,8 +1809,8 @@ void smp_spurious_interrupt(struct pt_regs *regs) { u32 v; - exit_idle(); irq_enter(); + exit_idle(); /* * Check if this really is a spurious interrupt and ACK it * if it is a vectored one. Just in case... @@ -1846,8 +1846,8 @@ void smp_error_interrupt(struct pt_regs *regs) "Illegal register address", /* APIC Error Bit 7 */ }; - exit_idle(); irq_enter(); + exit_idle(); /* First tickle the hardware, only then report what went on. -- REW */ v0 = apic_read(APIC_ESR); apic_write(APIC_ESR, 0); diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c index 6d939d7847e..89805558551 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -2421,8 +2421,8 @@ asmlinkage void smp_irq_move_cleanup_interrupt(void) unsigned vector, me; ack_APIC_irq(); - exit_idle(); irq_enter(); + exit_idle(); me = smp_processor_id(); for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) { diff --git a/arch/x86/kernel/cpu/mcheck/therm_throt.c b/arch/x86/kernel/cpu/mcheck/therm_throt.c index 787e06c84ea..ce215616d5b 100644 --- a/arch/x86/kernel/cpu/mcheck/therm_throt.c +++ b/arch/x86/kernel/cpu/mcheck/therm_throt.c @@ -397,8 +397,8 @@ static void (*smp_thermal_vector)(void) = unexpected_thermal_interrupt; asmlinkage void smp_thermal_interrupt(struct pt_regs *regs) { - exit_idle(); irq_enter(); + exit_idle(); inc_irq_stat(irq_thermal_count); smp_thermal_vector(); irq_exit(); diff --git a/arch/x86/kernel/cpu/mcheck/threshold.c b/arch/x86/kernel/cpu/mcheck/threshold.c index d746df2909c..aa578cadb94 100644 --- a/arch/x86/kernel/cpu/mcheck/threshold.c +++ b/arch/x86/kernel/cpu/mcheck/threshold.c @@ -19,8 +19,8 @@ void (*mce_threshold_vector)(void) = default_threshold_interrupt; asmlinkage void smp_threshold_interrupt(void) { - exit_idle(); irq_enter(); + exit_idle(); inc_irq_stat(irq_threshold_count); mce_threshold_vector(); irq_exit(); diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c index 429e0c92924..5d31e5bdbf8 100644 --- a/arch/x86/kernel/irq.c +++ b/arch/x86/kernel/irq.c @@ -181,8 +181,8 @@ unsigned int __irq_entry do_IRQ(struct pt_regs *regs) unsigned vector = ~regs->orig_ax; unsigned irq; - exit_idle(); irq_enter(); + exit_idle(); irq = __this_cpu_read(vector_irq[vector]); @@ -209,10 +209,10 @@ void smp_x86_platform_ipi(struct pt_regs *regs) ack_APIC_irq(); - exit_idle(); - irq_enter(); + exit_idle(); + inc_irq_stat(x86_platform_ipis); if (x86_platform_ipi_callback) -- cgit v1.2.3 From a7b152d5342c06e81ab0cf7d18345f69fa7e56b5 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 13 Oct 2011 19:05:12 -0700 Subject: powerpc: Tell RCU about idle after hcall tracing The PowerPC pSeries platform (CONFIG_PPC_PSERIES=y) enables hypervisor-call tracing for CONFIG_TRACEPOINTS=y kernels. One of the hypervisor calls that is traced is the H_CEDE call in the idle loop that tells the hypervisor that this OS instance no longer needs the current CPU. However, tracing uses RCU, so this combination of kernel configuration variables needs to avoid telling RCU about the current CPU's idleness until after the H_CEDE-entry tracing completes on the one hand, and must tell RCU that the the current CPU is no longer idle before the H_CEDE-exit tracing starts. In all other cases, it suffices to inform RCU of CPU idleness upon idle-loop entry and exit. This commit makes the required adjustments. Signed-off-by: Paul E. McKenney Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- arch/powerpc/kernel/idle.c | 16 ++++++++++++++-- arch/powerpc/platforms/pseries/lpar.c | 4 ++++ 2 files changed, 18 insertions(+), 2 deletions(-) (limited to 'arch') diff --git a/arch/powerpc/kernel/idle.c b/arch/powerpc/kernel/idle.c index 2e782a36d8f..3cd73d1fc42 100644 --- a/arch/powerpc/kernel/idle.c +++ b/arch/powerpc/kernel/idle.c @@ -46,6 +46,12 @@ static int __init powersave_off(char *arg) } __setup("powersave=off", powersave_off); +#if defined(CONFIG_PPC_PSERIES) && defined(CONFIG_TRACEPOINTS) +static const bool idle_uses_rcu = 1; +#else +static const bool idle_uses_rcu; +#endif + /* * The body of the idle task. */ @@ -56,7 +62,10 @@ void cpu_idle(void) set_thread_flag(TIF_POLLING_NRFLAG); while (1) { - tick_nohz_idle_enter_norcu(); + if (idle_uses_rcu) + tick_nohz_idle_enter(); + else + tick_nohz_idle_enter_norcu(); while (!need_resched() && !cpu_should_die()) { ppc64_runlatch_off(); @@ -93,7 +102,10 @@ void cpu_idle(void) HMT_medium(); ppc64_runlatch_on(); - tick_nohz_idle_exit_norcu(); + if (idle_uses_rcu) + tick_nohz_idle_exit(); + else + tick_nohz_idle_exit_norcu(); preempt_enable_no_resched(); if (cpu_should_die()) cpu_die(); diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c index 27a49508b41..52d429be6c7 100644 --- a/arch/powerpc/platforms/pseries/lpar.c +++ b/arch/powerpc/platforms/pseries/lpar.c @@ -555,6 +555,8 @@ void __trace_hcall_entry(unsigned long opcode, unsigned long *args) (*depth)++; trace_hcall_entry(opcode, args); + if (opcode == H_CEDE) + rcu_idle_enter(); (*depth)--; out: @@ -575,6 +577,8 @@ void __trace_hcall_exit(long opcode, unsigned long retval, goto out; (*depth)++; + if (opcode == H_CEDE) + rcu_idle_exit(); trace_hcall_exit(opcode, retval, retbuf); (*depth)--; -- cgit v1.2.3 From 29f043a2caea2860db36fbeda0c17f79bf0cffbe Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 10 Nov 2011 15:56:46 -0800 Subject: sparc: Make SPARC use the new is_idle_task() API Change from direct comparison of ->pid with zero to is_idle_task(). Signed-off-by: Paul E. McKenney Signed-off-by: Paul E. McKenney Acked-by: David S. Miller Reviewed-by: Josh Triplett --- arch/sparc/kernel/setup_32.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/sparc/kernel/setup_32.c b/arch/sparc/kernel/setup_32.c index fe1e3fc31bc..ffb883ddd0f 100644 --- a/arch/sparc/kernel/setup_32.c +++ b/arch/sparc/kernel/setup_32.c @@ -84,7 +84,7 @@ static void prom_sync_me(void) prom_printf("PROM SYNC COMMAND...\n"); show_free_areas(0); - if(current->pid != 0) { + if (!is_idle_task(current)) { local_irq_enable(); sys_sync(); local_irq_disable(); -- cgit v1.2.3 From a95f8817f8afa75ab41728bd1bb65024c65c91c3 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 10 Nov 2011 16:16:13 -0800 Subject: tile: Make tile use the new is_idle_task() API Change from direct comparison of ->pid with zero to is_idle_task(). Signed-off-by: Paul E. McKenney Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett Acked-by: Chris Metcalf --- arch/tile/mm/fault.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch') diff --git a/arch/tile/mm/fault.c b/arch/tile/mm/fault.c index 25b7b90fd62..c1eaaa1fcc2 100644 --- a/arch/tile/mm/fault.c +++ b/arch/tile/mm/fault.c @@ -54,7 +54,7 @@ static noinline void force_sig_info_fault(const char *type, int si_signo, if (unlikely(tsk->pid < 2)) { panic("Signal %d (code %d) at %#lx sent to %s!", si_signo, si_code & 0xffff, address, - tsk->pid ? "init" : "the idle task"); + is_idle_task(tsk) ? "the idle task" : "init"); } info.si_signo = si_signo; @@ -515,7 +515,7 @@ no_context: if (unlikely(tsk->pid < 2)) { panic("Kernel page fault running %s!", - tsk->pid ? "init" : "the idle task"); + is_idle_task(tsk) ? "the idle task" : "init"); } /* -- cgit v1.2.3 From 1268fbc746ea1cd279886a740dcbad4ba5232225 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Thu, 17 Nov 2011 18:48:14 +0100 Subject: nohz: Remove tick_nohz_idle_enter_norcu() / tick_nohz_idle_exit_norcu() Those two APIs were provided to optimize the calls of tick_nohz_idle_enter() and rcu_idle_enter() into a single irq disabled section. This way no interrupt happening in-between would needlessly process any RCU job. Now we are talking about an optimization for which benefits have yet to be measured. Let's start simple and completely decouple idle rcu and dyntick idle logics to simplify. Signed-off-by: Frederic Weisbecker Cc: Ingo Molnar Cc: Thomas Gleixner Cc: Peter Zijlstra Reviewed-by: Josh Triplett Signed-off-by: Paul E. McKenney --- arch/arm/kernel/process.c | 6 ++++-- arch/avr32/kernel/process.c | 6 ++++-- arch/blackfin/kernel/process.c | 6 ++++-- arch/microblaze/kernel/process.c | 6 ++++-- arch/mips/kernel/process.c | 6 ++++-- arch/openrisc/kernel/idle.c | 6 ++++-- arch/powerpc/kernel/idle.c | 15 +++++++-------- arch/powerpc/platforms/iseries/setup.c | 12 ++++++++---- arch/s390/kernel/process.c | 6 ++++-- arch/sh/kernel/idle.c | 6 ++++-- arch/sparc/kernel/process_64.c | 6 ++++-- arch/tile/kernel/process.c | 6 ++++-- arch/um/kernel/process.c | 6 ++++-- arch/unicore32/kernel/process.c | 6 ++++-- arch/x86/kernel/process_32.c | 6 ++++-- 15 files changed, 67 insertions(+), 38 deletions(-) (limited to 'arch') diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 47e34c09127..e8e8fe505df 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -183,7 +183,8 @@ void cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_idle_enter_norcu(); + tick_nohz_idle_enter(); + rcu_idle_enter(); leds_event(led_idle_start); while (!need_resched()) { #ifdef CONFIG_HOTPLUG_CPU @@ -213,7 +214,8 @@ void cpu_idle(void) } } leds_event(led_idle_end); - tick_nohz_idle_exit_norcu(); + rcu_idle_exit(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/avr32/kernel/process.c b/arch/avr32/kernel/process.c index 34c8c703bb1..ea339575032 100644 --- a/arch/avr32/kernel/process.c +++ b/arch/avr32/kernel/process.c @@ -34,10 +34,12 @@ void cpu_idle(void) { /* endless idle loop with no priority at all */ while (1) { - tick_nohz_idle_enter_norcu(); + tick_nohz_idle_enter(); + rcu_idle_enter(); while (!need_resched()) cpu_idle_sleep(); - tick_nohz_idle_exit_norcu(); + rcu_idle_exit(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/blackfin/kernel/process.c b/arch/blackfin/kernel/process.c index 57e07498a0e..8dd0416673c 100644 --- a/arch/blackfin/kernel/process.c +++ b/arch/blackfin/kernel/process.c @@ -88,10 +88,12 @@ void cpu_idle(void) #endif if (!idle) idle = default_idle; - tick_nohz_idle_enter_norcu(); + tick_nohz_idle_enter(); + rcu_idle_enter(); while (!need_resched()) idle(); - tick_nohz_idle_exit_norcu(); + rcu_idle_exit(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/microblaze/kernel/process.c b/arch/microblaze/kernel/process.c index 13d59f34b94..7dcb5bfffb7 100644 --- a/arch/microblaze/kernel/process.c +++ b/arch/microblaze/kernel/process.c @@ -103,10 +103,12 @@ void cpu_idle(void) if (!idle) idle = default_idle; - tick_nohz_idle_enter_norcu(); + tick_nohz_idle_enter(); + rcu_idle_enter(); while (!need_resched()) idle(); - tick_nohz_idle_exit_norcu(); + rcu_idle_exit(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c index 17fb3a27016..7955409051c 100644 --- a/arch/mips/kernel/process.c +++ b/arch/mips/kernel/process.c @@ -56,7 +56,8 @@ void __noreturn cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_idle_enter_norcu(); + tick_nohz_idle_enter(); + rcu_idle_enter(); while (!need_resched() && cpu_online(cpu)) { #ifdef CONFIG_MIPS_MT_SMTC extern void smtc_idle_loop_hook(void); @@ -77,7 +78,8 @@ void __noreturn cpu_idle(void) system_state == SYSTEM_BOOTING)) play_dead(); #endif - tick_nohz_idle_exit_norcu(); + rcu_idle_exit(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/openrisc/kernel/idle.c b/arch/openrisc/kernel/idle.c index 2e82cd0fa5e..e5fc7887783 100644 --- a/arch/openrisc/kernel/idle.c +++ b/arch/openrisc/kernel/idle.c @@ -51,7 +51,8 @@ void cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_idle_enter_norcu(); + tick_nohz_idle_enter(); + rcu_idle_enter(); while (!need_resched()) { check_pgt_cache(); @@ -69,7 +70,8 @@ void cpu_idle(void) set_thread_flag(TIF_POLLING_NRFLAG); } - tick_nohz_idle_exit_norcu(); + rcu_idle_exit(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/powerpc/kernel/idle.c b/arch/powerpc/kernel/idle.c index 3cd73d1fc42..9c3cd490b1b 100644 --- a/arch/powerpc/kernel/idle.c +++ b/arch/powerpc/kernel/idle.c @@ -62,10 +62,10 @@ void cpu_idle(void) set_thread_flag(TIF_POLLING_NRFLAG); while (1) { - if (idle_uses_rcu) - tick_nohz_idle_enter(); - else - tick_nohz_idle_enter_norcu(); + tick_nohz_idle_enter(); + if (!idle_uses_rcu) + rcu_idle_enter(); + while (!need_resched() && !cpu_should_die()) { ppc64_runlatch_off(); @@ -102,10 +102,9 @@ void cpu_idle(void) HMT_medium(); ppc64_runlatch_on(); - if (idle_uses_rcu) - tick_nohz_idle_exit(); - else - tick_nohz_idle_exit_norcu(); + if (!idle_uses_rcu) + rcu_idle_exit(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); if (cpu_should_die()) cpu_die(); diff --git a/arch/powerpc/platforms/iseries/setup.c b/arch/powerpc/platforms/iseries/setup.c index d69d3d185e8..8fc62586a97 100644 --- a/arch/powerpc/platforms/iseries/setup.c +++ b/arch/powerpc/platforms/iseries/setup.c @@ -563,7 +563,8 @@ static void yield_shared_processor(void) static void iseries_shared_idle(void) { while (1) { - tick_nohz_idle_enter_norcu(); + tick_nohz_idle_enter(); + rcu_idle_enter(); while (!need_resched() && !hvlpevent_is_pending()) { local_irq_disable(); ppc64_runlatch_off(); @@ -577,7 +578,8 @@ static void iseries_shared_idle(void) } ppc64_runlatch_on(); - tick_nohz_idle_exit_norcu(); + rcu_idle_exit(); + tick_nohz_idle_exit(); if (hvlpevent_is_pending()) process_iSeries_events(); @@ -593,7 +595,8 @@ static void iseries_dedicated_idle(void) set_thread_flag(TIF_POLLING_NRFLAG); while (1) { - tick_nohz_idle_enter_norcu(); + tick_nohz_idle_enter(); + rcu_idle_enter(); if (!need_resched()) { while (!need_resched()) { ppc64_runlatch_off(); @@ -610,7 +613,8 @@ static void iseries_dedicated_idle(void) } ppc64_runlatch_on(); - tick_nohz_idle_exit_norcu(); + rcu_idle_exit(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c index 6fa987367ae..3201ae44799 100644 --- a/arch/s390/kernel/process.c +++ b/arch/s390/kernel/process.c @@ -91,10 +91,12 @@ static void default_idle(void) void cpu_idle(void) { for (;;) { - tick_nohz_idle_enter_norcu(); + tick_nohz_idle_enter(); + rcu_idle_enter(); while (!need_resched()) default_idle(); - tick_nohz_idle_exit_norcu(); + rcu_idle_exit(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/sh/kernel/idle.c b/arch/sh/kernel/idle.c index ad58e7535a7..406508d4ce7 100644 --- a/arch/sh/kernel/idle.c +++ b/arch/sh/kernel/idle.c @@ -89,7 +89,8 @@ void cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_idle_enter_norcu(); + tick_nohz_idle_enter(); + rcu_idle_enter(); while (!need_resched()) { check_pgt_cache(); @@ -111,7 +112,8 @@ void cpu_idle(void) start_critical_timings(); } - tick_nohz_idle_exit_norcu(); + rcu_idle_exit(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/sparc/kernel/process_64.c b/arch/sparc/kernel/process_64.c index 4a0e7d79cb9..39d8b05201a 100644 --- a/arch/sparc/kernel/process_64.c +++ b/arch/sparc/kernel/process_64.c @@ -95,12 +95,14 @@ void cpu_idle(void) set_thread_flag(TIF_POLLING_NRFLAG); while(1) { - tick_nohz_idle_enter_norcu(); + tick_nohz_idle_enter(); + rcu_idle_enter(); while (!need_resched() && !cpu_is_offline(cpu)) sparc64_yield(cpu); - tick_nohz_idle_exit_norcu(); + rcu_idle_exit(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); diff --git a/arch/tile/kernel/process.c b/arch/tile/kernel/process.c index 53ac89595ab..4c1ac6e5347 100644 --- a/arch/tile/kernel/process.c +++ b/arch/tile/kernel/process.c @@ -85,7 +85,8 @@ void cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_idle_enter_norcu(); + tick_nohz_idle_enter(); + rcu_idle_enter(); while (!need_resched()) { if (cpu_is_offline(cpu)) BUG(); /* no HOTPLUG_CPU */ @@ -105,7 +106,8 @@ void cpu_idle(void) local_irq_enable(); current_thread_info()->status |= TS_POLLING; } - tick_nohz_idle_exit_norcu(); + rcu_idle_exit(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c index 55d2cf455f6..69f24905abd 100644 --- a/arch/um/kernel/process.c +++ b/arch/um/kernel/process.c @@ -246,10 +246,12 @@ void default_idle(void) if (need_resched()) schedule(); - tick_nohz_idle_enter_norcu(); + tick_nohz_idle_enter(); + rcu_idle_enter(); nsecs = disable_timer(); idle_sleep(nsecs); - tick_nohz_idle_exit_norcu(); + rcu_idle_exit(); + tick_nohz_idle_exit(); } } diff --git a/arch/unicore32/kernel/process.c b/arch/unicore32/kernel/process.c index 095ff5a5792..52edc2b6287 100644 --- a/arch/unicore32/kernel/process.c +++ b/arch/unicore32/kernel/process.c @@ -55,7 +55,8 @@ void cpu_idle(void) { /* endless idle loop with no priority at all */ while (1) { - tick_nohz_idle_enter_norcu(); + tick_nohz_idle_enter(); + rcu_idle_enter(); while (!need_resched()) { local_irq_disable(); stop_critical_timings(); @@ -63,7 +64,8 @@ void cpu_idle(void) local_irq_enable(); start_critical_timings(); } - tick_nohz_idle_exit_norcu(); + rcu_idle_exit(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index f94da3920c3..485204f58cd 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -99,7 +99,8 @@ void cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_idle_enter_norcu(); + tick_nohz_idle_enter(); + rcu_idle_enter(); while (!need_resched()) { check_pgt_cache(); @@ -116,7 +117,8 @@ void cpu_idle(void) pm_idle(); start_critical_timings(); } - tick_nohz_idle_exit_norcu(); + rcu_idle_exit(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); -- cgit v1.2.3