diff options
| -rw-r--r-- | arch/ppc64/kernel/pSeries_setup.c | 113 |
1 files changed, 62 insertions, 51 deletions
diff --git a/arch/ppc64/kernel/pSeries_setup.c b/arch/ppc64/kernel/pSeries_setup.c index 3f3be8ae9351..5bec956e44a0 100644 --- a/arch/ppc64/kernel/pSeries_setup.c +++ b/arch/ppc64/kernel/pSeries_setup.c @@ -83,8 +83,8 @@ int fwnmi_active; /* TRUE if an FWNMI handler is present */ extern void pSeries_system_reset_exception(struct pt_regs *regs); extern int pSeries_machine_check_exception(struct pt_regs *regs); -static int shared_idle(void); -static int dedicated_idle(void); +static int pseries_shared_idle(void); +static int pseries_dedicated_idle(void); static volatile void __iomem * chrp_int_ack_special; struct mpic *pSeries_mpic; @@ -238,10 +238,10 @@ static void __init pSeries_setup_arch(void) if (cur_cpu_spec->firmware_features & FW_FEATURE_SPLPAR) { if (get_paca()->lppaca.shared_proc) { printk(KERN_INFO "Using shared processor idle loop\n"); - ppc_md.idle_loop = shared_idle; + ppc_md.idle_loop = pseries_shared_idle; } else { printk(KERN_INFO "Using dedicated idle loop\n"); - ppc_md.idle_loop = dedicated_idle; + ppc_md.idle_loop = pseries_dedicated_idle; } } else { printk(KERN_INFO "Using default idle loop\n"); @@ -438,15 +438,47 @@ static int __init pSeries_probe(int platform) DECLARE_PER_CPU(unsigned long, smt_snooze_delay); -int dedicated_idle(void) +static inline void dedicated_idle_sleep(unsigned int cpu) +{ + struct paca_struct *ppaca = &paca[cpu ^ 1]; + + /* Only sleep if the other thread is not idle */ + if (!(ppaca->lppaca.idle)) { + local_irq_disable(); + + /* + * We are about to sleep the thread and so wont be polling any + * more. + */ + clear_thread_flag(TIF_POLLING_NRFLAG); + + /* + * SMT dynamic mode. Cede will result in this thread going + * dormant, if the partner thread is still doing work. Thread + * wakes up if partner goes idle, an interrupt is presented, or + * a prod occurs. Returning from the cede enables external + * interrupts. + */ + if (!need_resched()) + cede_processor(); + else + local_irq_enable(); + } else { + /* + * Give the HV an opportunity at the processor, since we are + * not doing any work. + */ + poll_pending(); + } +} + +static int pseries_dedicated_idle(void) { long oldval; - struct paca_struct *lpaca = get_paca(), *ppaca; + struct paca_struct *lpaca = get_paca(); + unsigned int cpu = smp_processor_id(); unsigned long start_snooze; unsigned long *smt_snooze_delay = &__get_cpu_var(smt_snooze_delay); - unsigned int cpu = smp_processor_id(); - - ppaca = &paca[cpu ^ 1]; while (1) { /* @@ -458,9 +490,13 @@ int dedicated_idle(void) oldval = test_and_clear_thread_flag(TIF_NEED_RESCHED); if (!oldval) { set_thread_flag(TIF_POLLING_NRFLAG); + start_snooze = __get_tb() + *smt_snooze_delay * tb_ticks_per_usec; + while (!need_resched() && !cpu_is_offline(cpu)) { + ppc64_runlatch_off(); + /* * Go into low thread priority and possibly * low power mode. @@ -468,60 +504,31 @@ int dedicated_idle(void) HMT_low(); HMT_very_low(); - if (*smt_snooze_delay == 0 || - __get_tb() < start_snooze) - continue; - - HMT_medium(); - - if (!(ppaca->lppaca.idle)) { - local_irq_disable(); - - /* - * We are about to sleep the thread - * and so wont be polling any - * more. - */ - clear_thread_flag(TIF_POLLING_NRFLAG); - - /* - * SMT dynamic mode. Cede will result - * in this thread going dormant, if the - * partner thread is still doing work. - * Thread wakes up if partner goes idle, - * an interrupt is presented, or a prod - * occurs. Returning from the cede - * enables external interrupts. - */ - if (!need_resched()) - cede_processor(); - else - local_irq_enable(); - } else { - /* - * Give the HV an opportunity at the - * processor, since we are not doing - * any work. - */ - poll_pending(); + if (*smt_snooze_delay != 0 && + __get_tb() > start_snooze) { + HMT_medium(); + dedicated_idle_sleep(cpu); } + } + HMT_medium(); clear_thread_flag(TIF_POLLING_NRFLAG); } else { set_need_resched(); } - HMT_medium(); lpaca->lppaca.idle = 0; + ppc64_runlatch_on(); + schedule(); + if (cpu_is_offline(cpu) && system_state == SYSTEM_RUNNING) cpu_die(); } - return 0; } -static int shared_idle(void) +static int pseries_shared_idle(void) { struct paca_struct *lpaca = get_paca(); unsigned int cpu = smp_processor_id(); @@ -535,6 +542,7 @@ static int shared_idle(void) while (!need_resched() && !cpu_is_offline(cpu)) { local_irq_disable(); + ppc64_runlatch_off(); /* * Yield the processor to the hypervisor. We return if @@ -550,13 +558,16 @@ static int shared_idle(void) cede_processor(); else local_irq_enable(); + + HMT_medium(); } - HMT_medium(); lpaca->lppaca.idle = 0; + ppc64_runlatch_on(); + schedule(); - if (cpu_is_offline(smp_processor_id()) && - system_state == SYSTEM_RUNNING) + + if (cpu_is_offline(cpu) && system_state == SYSTEM_RUNNING) cpu_die(); } |