diff options
Diffstat (limited to 'arch/powerpc/kernel/time.c')
| -rw-r--r-- | arch/powerpc/kernel/time.c | 148 |
1 files changed, 113 insertions, 35 deletions
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index 3ed9a5a21d77..4e7759c8ca30 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -96,7 +96,8 @@ static struct clocksource clocksource_timebase = { .read = timebase_read, }; -#define DECREMENTER_MAX 0x7fffffff +#define DECREMENTER_DEFAULT_MAX 0x7FFFFFFF +u64 decrementer_max = DECREMENTER_DEFAULT_MAX; static int decrementer_set_next_event(unsigned long evt, struct clock_event_device *dev); @@ -166,7 +167,15 @@ DEFINE_PER_CPU(unsigned long, cputime_scaled_last_delta); cputime_t cputime_one_jiffy; +#ifdef CONFIG_PPC_SPLPAR void (*dtl_consumer)(struct dtl_entry *, u64); +#endif + +#ifdef CONFIG_PPC64 +#define get_accounting(tsk) (&get_paca()->accounting) +#else +#define get_accounting(tsk) (&task_thread_info(tsk)->accounting) +#endif static void calc_cputime_factors(void) { @@ -186,7 +195,7 @@ static void calc_cputime_factors(void) * Read the SPURR on systems that have it, otherwise the PURR, * or if that doesn't exist return the timebase value passed in. */ -static u64 read_spurr(u64 tb) +static unsigned long read_spurr(unsigned long tb) { if (cpu_has_feature(CPU_FTR_SPURR)) return mfspr(SPRN_SPURR); @@ -249,8 +258,8 @@ static u64 scan_dispatch_log(u64 stop_tb) void accumulate_stolen_time(void) { u64 sst, ust; - u8 save_soft_enabled = local_paca->soft_enabled; + struct cpu_accounting_data *acct = &local_paca->accounting; /* We are called early in the exception entry, before * soft/hard_enabled are sync'ed to the expected state @@ -260,10 +269,10 @@ void accumulate_stolen_time(void) */ local_paca->soft_enabled = 0; - sst = scan_dispatch_log(local_paca->starttime_user); - ust = scan_dispatch_log(local_paca->starttime); - local_paca->system_time -= sst; - local_paca->user_time -= ust; + sst = scan_dispatch_log(acct->starttime_user); + ust = scan_dispatch_log(acct->starttime); + acct->system_time -= sst; + acct->user_time -= ust; local_paca->stolen_time += ust + sst; local_paca->soft_enabled = save_soft_enabled; @@ -275,7 +284,7 @@ static inline u64 calculate_stolen_time(u64 stop_tb) if (get_paca()->dtl_ridx != be64_to_cpu(get_lppaca()->dtl_idx)) { stolen = scan_dispatch_log(stop_tb); - get_paca()->system_time -= stolen; + get_paca()->accounting.system_time -= stolen; } stolen += get_paca()->stolen_time; @@ -295,27 +304,29 @@ static inline u64 calculate_stolen_time(u64 stop_tb) * Account time for a transition between system, hard irq * or soft irq state. */ -static u64 vtime_delta(struct task_struct *tsk, - u64 *sys_scaled, u64 *stolen) +static unsigned long vtime_delta(struct task_struct *tsk, + unsigned long *sys_scaled, + unsigned long *stolen) { - u64 now, nowscaled, deltascaled; - u64 udelta, delta, user_scaled; + unsigned long now, nowscaled, deltascaled; + unsigned long udelta, delta, user_scaled; + struct cpu_accounting_data *acct = get_accounting(tsk); WARN_ON_ONCE(!irqs_disabled()); now = mftb(); nowscaled = read_spurr(now); - get_paca()->system_time += now - get_paca()->starttime; - get_paca()->starttime = now; - deltascaled = nowscaled - get_paca()->startspurr; - get_paca()->startspurr = nowscaled; + acct->system_time += now - acct->starttime; + acct->starttime = now; + deltascaled = nowscaled - acct->startspurr; + acct->startspurr = nowscaled; *stolen = calculate_stolen_time(now); - delta = get_paca()->system_time; - get_paca()->system_time = 0; - udelta = get_paca()->user_time - get_paca()->utime_sspurr; - get_paca()->utime_sspurr = get_paca()->user_time; + delta = acct->system_time; + acct->system_time = 0; + udelta = acct->user_time - acct->utime_sspurr; + acct->utime_sspurr = acct->user_time; /* * Because we don't read the SPURR on every kernel entry/exit, @@ -337,14 +348,14 @@ static u64 vtime_delta(struct task_struct *tsk, *sys_scaled = deltascaled; } } - get_paca()->user_time_scaled += user_scaled; + acct->user_time_scaled += user_scaled; return delta; } void vtime_account_system(struct task_struct *tsk) { - u64 delta, sys_scaled, stolen; + unsigned long delta, sys_scaled, stolen; delta = vtime_delta(tsk, &sys_scaled, &stolen); account_system_time(tsk, 0, delta, sys_scaled); @@ -355,7 +366,7 @@ EXPORT_SYMBOL_GPL(vtime_account_system); void vtime_account_idle(struct task_struct *tsk) { - u64 delta, sys_scaled, stolen; + unsigned long delta, sys_scaled, stolen; delta = vtime_delta(tsk, &sys_scaled, &stolen); account_idle_time(delta + stolen); @@ -373,15 +384,32 @@ void vtime_account_idle(struct task_struct *tsk) void vtime_account_user(struct task_struct *tsk) { cputime_t utime, utimescaled; + struct cpu_accounting_data *acct = get_accounting(tsk); - utime = get_paca()->user_time; - utimescaled = get_paca()->user_time_scaled; - get_paca()->user_time = 0; - get_paca()->user_time_scaled = 0; - get_paca()->utime_sspurr = 0; + utime = acct->user_time; + utimescaled = acct->user_time_scaled; + acct->user_time = 0; + acct->user_time_scaled = 0; + acct->utime_sspurr = 0; account_user_time(tsk, utime, utimescaled); } +#ifdef CONFIG_PPC32 +/* + * Called from the context switch with interrupts disabled, to charge all + * accumulated times to the current process, and to prepare accounting on + * the next process. + */ +void arch_vtime_task_switch(struct task_struct *prev) +{ + struct cpu_accounting_data *acct = get_accounting(current); + + acct->starttime = get_accounting(prev)->starttime; + acct->system_time = 0; + acct->user_time = 0; +} +#endif /* CONFIG_PPC32 */ + #else /* ! CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ #define calc_cputime_factors() #endif @@ -504,8 +532,8 @@ static void __timer_interrupt(void) __this_cpu_inc(irq_stat.timer_irqs_event); } else { now = *next_tb - now; - if (now <= DECREMENTER_MAX) - set_dec((int)now); + if (now <= decrementer_max) + set_dec(now); /* We may have raced with new irq work */ if (test_irq_work_pending()) set_dec(1); @@ -535,7 +563,7 @@ void timer_interrupt(struct pt_regs * regs) /* Ensure a positive value is written to the decrementer, or else * some CPUs will continue to take decrementer exceptions. */ - set_dec(DECREMENTER_MAX); + set_dec(decrementer_max); /* Some implementations of hotplug will get timer interrupts while * offline, just ignore these and we also need to set @@ -583,9 +611,9 @@ static void generic_suspend_disable_irqs(void) * with suspending. */ - set_dec(DECREMENTER_MAX); + set_dec(decrementer_max); local_irq_disable(); - set_dec(DECREMENTER_MAX); + set_dec(decrementer_max); } static void generic_suspend_enable_irqs(void) @@ -866,7 +894,7 @@ static int decrementer_set_next_event(unsigned long evt, static int decrementer_shutdown(struct clock_event_device *dev) { - decrementer_set_next_event(DECREMENTER_MAX, dev); + decrementer_set_next_event(decrementer_max, dev); return 0; } @@ -892,6 +920,49 @@ static void register_decrementer_clockevent(int cpu) clockevents_register_device(dec); } +static void enable_large_decrementer(void) +{ + if (!cpu_has_feature(CPU_FTR_ARCH_300)) + return; + + if (decrementer_max <= DECREMENTER_DEFAULT_MAX) + return; + + /* + * If we're running as the hypervisor we need to enable the LD manually + * otherwise firmware should have done it for us. + */ + if (cpu_has_feature(CPU_FTR_HVMODE)) + mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) | LPCR_LD); +} + +static void __init set_decrementer_max(void) +{ + struct device_node *cpu; + u32 bits = 32; + + /* Prior to ISAv3 the decrementer is always 32 bit */ + if (!cpu_has_feature(CPU_FTR_ARCH_300)) + return; + + cpu = of_find_node_by_type(NULL, "cpu"); + + if (of_property_read_u32(cpu, "ibm,dec-bits", &bits) == 0) { + if (bits > 64 || bits < 32) { + pr_warn("time_init: firmware supplied invalid ibm,dec-bits"); + bits = 32; + } + + /* calculate the signed maximum given this many bits */ + decrementer_max = (1ul << (bits - 1)) - 1; + } + + of_node_put(cpu); + + pr_info("time_init: %u bit decrementer (max: %llx)\n", + bits, decrementer_max); +} + static void __init init_decrementer_clockevent(void) { int cpu = smp_processor_id(); @@ -899,7 +970,7 @@ static void __init init_decrementer_clockevent(void) clockevents_calc_mult_shift(&decrementer_clockevent, ppc_tb_freq, 4); decrementer_clockevent.max_delta_ns = - clockevent_delta2ns(DECREMENTER_MAX, &decrementer_clockevent); + clockevent_delta2ns(decrementer_max, &decrementer_clockevent); decrementer_clockevent.min_delta_ns = clockevent_delta2ns(2, &decrementer_clockevent); @@ -908,6 +979,9 @@ static void __init init_decrementer_clockevent(void) void secondary_cpu_time_init(void) { + /* Enable and test the large decrementer for this cpu */ + enable_large_decrementer(); + /* Start the decrementer on CPUs that have manual control * such as BookE */ @@ -973,6 +1047,10 @@ void __init time_init(void) vdso_data->tb_update_count = 0; vdso_data->tb_ticks_per_sec = tb_ticks_per_sec; + /* initialise and enable the large decrementer (if we have one) */ + set_decrementer_max(); + enable_large_decrementer(); + /* Start the decrementer on CPUs that have manual control * such as BookE */ |