diff options
Diffstat (limited to 'arch/powerpc/kernel/time.c')
| -rw-r--r-- | arch/powerpc/kernel/time.c | 248 |
1 files changed, 88 insertions, 160 deletions
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index 587adcc12860..8224381c1dba 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -71,11 +71,11 @@ #include <asm/vdso_datapage.h> #include <asm/firmware.h> #include <asm/mce.h> +#include <asm/systemcfg.h> /* powerpc clocksource/clockevent code */ #include <linux/clockchips.h> -#include <linux/timekeeper_internal.h> static u64 timebase_read(struct clocksource *); static struct clocksource clocksource_timebase = { @@ -130,7 +130,7 @@ unsigned long tb_ticks_per_jiffy; unsigned long tb_ticks_per_usec = 100; /* sane default */ EXPORT_SYMBOL(tb_ticks_per_usec); unsigned long tb_ticks_per_sec; -EXPORT_SYMBOL(tb_ticks_per_sec); /* for cputime_t conversions */ +EXPORT_SYMBOL(tb_ticks_per_sec); /* for cputime conversions */ DEFINE_SPINLOCK(rtc_lock); EXPORT_SYMBOL_GPL(rtc_lock); @@ -151,21 +151,6 @@ bool tb_invalid; #ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE /* - * Factor for converting from cputime_t (timebase ticks) to - * microseconds. This is stored as 0.64 fixed-point binary fraction. - */ -u64 __cputime_usec_factor; -EXPORT_SYMBOL(__cputime_usec_factor); - -static void calc_cputime_factors(void) -{ - struct div_result res; - - div128_by_32(1000000, 0, tb_ticks_per_sec, &res); - __cputime_usec_factor = res.result_low; -} - -/* * Read the SPURR on systems that have it, otherwise the PURR, * or if that doesn't exist return the timebase value passed in. */ @@ -178,92 +163,6 @@ static inline unsigned long read_spurr(unsigned long tb) return tb; } -#ifdef CONFIG_PPC_SPLPAR - -#include <asm/dtl.h> - -void (*dtl_consumer)(struct dtl_entry *, u64); - -/* - * Scan the dispatch trace log and count up the stolen time. - * Should be called with interrupts disabled. - */ -static u64 scan_dispatch_log(u64 stop_tb) -{ - u64 i = local_paca->dtl_ridx; - struct dtl_entry *dtl = local_paca->dtl_curr; - struct dtl_entry *dtl_end = local_paca->dispatch_log_end; - struct lppaca *vpa = local_paca->lppaca_ptr; - u64 tb_delta; - u64 stolen = 0; - u64 dtb; - - if (!dtl) - return 0; - - if (i == be64_to_cpu(vpa->dtl_idx)) - return 0; - while (i < be64_to_cpu(vpa->dtl_idx)) { - dtb = be64_to_cpu(dtl->timebase); - tb_delta = be32_to_cpu(dtl->enqueue_to_dispatch_time) + - be32_to_cpu(dtl->ready_to_enqueue_time); - barrier(); - if (i + N_DISPATCH_LOG < be64_to_cpu(vpa->dtl_idx)) { - /* buffer has overflowed */ - i = be64_to_cpu(vpa->dtl_idx) - N_DISPATCH_LOG; - dtl = local_paca->dispatch_log + (i % N_DISPATCH_LOG); - continue; - } - if (dtb > stop_tb) - break; - if (dtl_consumer) - dtl_consumer(dtl, i); - stolen += tb_delta; - ++i; - ++dtl; - if (dtl == dtl_end) - dtl = local_paca->dispatch_log; - } - local_paca->dtl_ridx = i; - local_paca->dtl_curr = dtl; - return stolen; -} - -/* - * Accumulate stolen time by scanning the dispatch trace log. - * Called on entry from user mode. - */ -void notrace accumulate_stolen_time(void) -{ - u64 sst, ust; - struct cpu_accounting_data *acct = &local_paca->accounting; - - sst = scan_dispatch_log(acct->starttime_user); - ust = scan_dispatch_log(acct->starttime); - acct->stime -= sst; - acct->utime -= ust; - acct->steal_time += ust + sst; -} - -static inline u64 calculate_stolen_time(u64 stop_tb) -{ - if (!firmware_has_feature(FW_FEATURE_SPLPAR)) - return 0; - - if (get_paca()->dtl_ridx != be64_to_cpu(get_lppaca()->dtl_idx)) - return scan_dispatch_log(stop_tb); - - return 0; -} - -#else /* CONFIG_PPC_SPLPAR */ -static inline u64 calculate_stolen_time(u64 stop_tb) -{ - return 0; -} - -#endif /* CONFIG_PPC_SPLPAR */ - /* * Account time for a transition between system, hard irq * or soft irq state. @@ -322,7 +221,11 @@ static unsigned long vtime_delta(struct cpu_accounting_data *acct, *stime_scaled = vtime_delta_scaled(acct, now, stime); - *steal_time = calculate_stolen_time(now); + if (IS_ENABLED(CONFIG_PPC_SPLPAR) && + firmware_has_feature(FW_FEATURE_SPLPAR)) + *steal_time = pseries_calculate_stolen_time(now); + else + *steal_time = 0; return stime; } @@ -452,11 +355,30 @@ void vtime_flush(struct task_struct *tsk) acct->softirq_time = 0; } -#else /* ! CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ -#define calc_cputime_factors() -#endif +/* + * 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 vtime_task_switch(struct task_struct *prev) +{ + if (is_idle_task(prev)) + vtime_account_idle(prev); + else + vtime_account_kernel(prev); + + vtime_flush(prev); + + if (!IS_ENABLED(CONFIG_PPC64)) { + struct cpu_accounting_data *acct = get_accounting(current); + struct cpu_accounting_data *acct0 = get_accounting(prev); + + acct->starttime = acct0->starttime; + } +} +#endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ -void __delay(unsigned long loops) +void __no_kcsan __delay(unsigned long loops) { unsigned long start; @@ -477,7 +399,7 @@ void __delay(unsigned long loops) } EXPORT_SYMBOL(__delay); -void udelay(unsigned long usecs) +void __no_kcsan udelay(unsigned long usecs) { __delay(tb_ticks_per_usec * usecs); } @@ -614,22 +536,23 @@ DEFINE_INTERRUPT_HANDLER_ASYNC(timer_interrupt) return; } - /* - * Ensure a positive value is written to the decrementer, or - * else some CPUs will continue to take decrementer exceptions. - * When the PPC_WATCHDOG (decrementer based) is configured, - * keep this at most 31 bits, which is about 4 seconds on most - * systems, which gives the watchdog a chance of catching timer - * interrupt hard lockups. - */ - if (IS_ENABLED(CONFIG_PPC_WATCHDOG)) - set_dec(0x7fffffff); - else - set_dec(decrementer_max); - /* Conditionally hard-enable interrupts. */ - if (should_hard_irq_enable()) + if (should_hard_irq_enable(regs)) { + /* + * Ensure a positive value is written to the decrementer, or + * else some CPUs will continue to take decrementer exceptions. + * When the PPC_WATCHDOG (decrementer based) is configured, + * keep this at most 31 bits, which is about 4 seconds on most + * systems, which gives the watchdog a chance of catching timer + * interrupt hard lockups. + */ + if (IS_ENABLED(CONFIG_PPC_WATCHDOG)) + set_dec(0x7fffffff); + else + set_dec(decrementer_max); + do_hard_irq_enable(); + } #if defined(CONFIG_PPC32) && defined(CONFIG_PPC_PMAC) if (atomic_read(&ppc_n_lost_interrupts) != 0) @@ -772,7 +695,7 @@ static int __init get_freq(char *name, int cells, unsigned long *val) static void start_cpu_decrementer(void) { -#ifdef CONFIG_BOOKE_OR_40x +#ifdef CONFIG_BOOKE unsigned int tcr; /* Clear any pending timer interrupts */ @@ -978,6 +901,38 @@ void secondary_cpu_time_init(void) register_decrementer_clockevent(smp_processor_id()); } +/* + * Divide a 128-bit dividend by a 32-bit divisor, leaving a 128 bit + * result. + */ +static __init void div128_by_32(u64 dividend_high, u64 dividend_low, + unsigned int divisor, struct div_result *dr) +{ + unsigned long a, b, c, d; + unsigned long w, x, y, z; + u64 ra, rb, rc; + + a = dividend_high >> 32; + b = dividend_high & 0xffffffff; + c = dividend_low >> 32; + d = dividend_low & 0xffffffff; + + w = a / divisor; + ra = ((u64)(a - (w * divisor)) << 32) + b; + + rb = ((u64)do_div(ra, divisor) << 32) + c; + x = ra; + + rc = ((u64)do_div(rb, divisor) << 32) + d; + y = rb; + + do_div(rc, divisor); + z = rc; + + dr->result_high = ((u64)w << 32) + x; + dr->result_low = ((u64)y << 32) + z; +} + /* This function is only called on the boot processor */ void __init time_init(void) { @@ -986,7 +941,11 @@ void __init time_init(void) unsigned shift; /* Normal PowerPC with timebase register */ - ppc_md.calibrate_decr(); + if (ppc_md.calibrate_decr) + ppc_md.calibrate_decr(); + else + generic_calibrate_decr(); + printk(KERN_DEBUG "time_init: decrementer frequency = %lu.%.6lu MHz\n", ppc_tb_freq / 1000000, ppc_tb_freq % 1000000); printk(KERN_DEBUG "time_init: processor frequency = %lu.%.6lu MHz\n", @@ -995,7 +954,6 @@ void __init time_init(void) tb_ticks_per_jiffy = ppc_tb_freq / HZ; tb_ticks_per_sec = ppc_tb_freq; tb_ticks_per_usec = ppc_tb_freq / 1000000; - calc_cputime_factors(); /* * Compute scale factor for sched_clock. @@ -1024,7 +982,10 @@ void __init time_init(void) sys_tz.tz_dsttime = 0; } - vdso_data->tb_ticks_per_sec = tb_ticks_per_sec; + vdso_k_arch_data->tb_ticks_per_sec = tb_ticks_per_sec; +#ifdef CONFIG_PPC64_PROC_SYSTEMCFG + systemcfg->tb_ticks_per_sec = tb_ticks_per_sec; +#endif /* initialise and enable the large decrementer (if we have one) */ set_decrementer_max(); @@ -1045,39 +1006,6 @@ void __init time_init(void) enable_sched_clock_irqtime(); } -/* - * Divide a 128-bit dividend by a 32-bit divisor, leaving a 128 bit - * result. - */ -void div128_by_32(u64 dividend_high, u64 dividend_low, - unsigned divisor, struct div_result *dr) -{ - unsigned long a, b, c, d; - unsigned long w, x, y, z; - u64 ra, rb, rc; - - a = dividend_high >> 32; - b = dividend_high & 0xffffffff; - c = dividend_low >> 32; - d = dividend_low & 0xffffffff; - - w = a / divisor; - ra = ((u64)(a - (w * divisor)) << 32) + b; - - rb = ((u64) do_div(ra, divisor) << 32) + c; - x = ra; - - rc = ((u64) do_div(rb, divisor) << 32) + d; - y = rb; - - do_div(rc, divisor); - z = rc; - - dr->result_high = ((u64)w << 32) + x; - dr->result_low = ((u64)y << 32) + z; - -} - /* We don't need to calibrate delay, we use the CPU timebase for that */ void calibrate_delay(void) { |