X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=kernel%2Ftime.c;h=c6c80ea5d0ead904ac73030616ba02c5b2a5f7d9;hb=f630fe2817601314b2eb7ca5ddc23c7834646731;hp=b00ddc71cedb860f5793978a13868e4de5862f0f;hpb=76467874b83835129dc454e3a7a8e5d1186101b0;p=pandora-kernel.git diff --git a/kernel/time.c b/kernel/time.c index b00ddc71cedb..c6c80ea5d0ea 100644 --- a/kernel/time.c +++ b/kernel/time.c @@ -202,179 +202,6 @@ asmlinkage long sys_settimeofday(struct timeval __user *tv, return do_sys_settimeofday(tv ? &new_ts : NULL, tz ? &new_tz : NULL); } -/* we call this to notify the arch when the clock is being - * controlled. If no such arch routine, do nothing. - */ -void __attribute__ ((weak)) notify_arch_cmos_timer(void) -{ - return; -} - -/* adjtimex mainly allows reading (and writing, if superuser) of - * kernel time-keeping variables. used by xntpd. - */ -int do_adjtimex(struct timex *txc) -{ - long ltemp, mtemp, save_adjust; - int result; - - /* In order to modify anything, you gotta be super-user! */ - if (txc->modes && !capable(CAP_SYS_TIME)) - return -EPERM; - - /* Now we validate the data before disabling interrupts */ - - if ((txc->modes & ADJ_OFFSET_SINGLESHOT) == ADJ_OFFSET_SINGLESHOT) - /* singleshot must not be used with any other mode bits */ - if (txc->modes != ADJ_OFFSET_SINGLESHOT) - return -EINVAL; - - if (txc->modes != ADJ_OFFSET_SINGLESHOT && (txc->modes & ADJ_OFFSET)) - /* adjustment Offset limited to +- .512 seconds */ - if (txc->offset <= - MAXPHASE || txc->offset >= MAXPHASE ) - return -EINVAL; - - /* if the quartz is off by more than 10% something is VERY wrong ! */ - if (txc->modes & ADJ_TICK) - if (txc->tick < 900000/USER_HZ || - txc->tick > 1100000/USER_HZ) - return -EINVAL; - - write_seqlock_irq(&xtime_lock); - result = time_state; /* mostly `TIME_OK' */ - - /* Save for later - semantics of adjtime is to return old value */ - save_adjust = time_next_adjust ? time_next_adjust : time_adjust; - -#if 0 /* STA_CLOCKERR is never set yet */ - time_status &= ~STA_CLOCKERR; /* reset STA_CLOCKERR */ -#endif - /* If there are input parameters, then process them */ - if (txc->modes) - { - if (txc->modes & ADJ_STATUS) /* only set allowed bits */ - time_status = (txc->status & ~STA_RONLY) | - (time_status & STA_RONLY); - - if (txc->modes & ADJ_FREQUENCY) { /* p. 22 */ - if (txc->freq > MAXFREQ || txc->freq < -MAXFREQ) { - result = -EINVAL; - goto leave; - } - time_freq = txc->freq; - } - - if (txc->modes & ADJ_MAXERROR) { - if (txc->maxerror < 0 || txc->maxerror >= NTP_PHASE_LIMIT) { - result = -EINVAL; - goto leave; - } - time_maxerror = txc->maxerror; - } - - if (txc->modes & ADJ_ESTERROR) { - if (txc->esterror < 0 || txc->esterror >= NTP_PHASE_LIMIT) { - result = -EINVAL; - goto leave; - } - time_esterror = txc->esterror; - } - - if (txc->modes & ADJ_TIMECONST) { /* p. 24 */ - if (txc->constant < 0) { /* NTP v4 uses values > 6 */ - result = -EINVAL; - goto leave; - } - time_constant = txc->constant; - } - - if (txc->modes & ADJ_OFFSET) { /* values checked earlier */ - if (txc->modes == ADJ_OFFSET_SINGLESHOT) { - /* adjtime() is independent from ntp_adjtime() */ - if ((time_next_adjust = txc->offset) == 0) - time_adjust = 0; - } - else if (time_status & STA_PLL) { - ltemp = txc->offset; - - /* - * Scale the phase adjustment and - * clamp to the operating range. - */ - if (ltemp > MAXPHASE) - time_offset = MAXPHASE << SHIFT_UPDATE; - else if (ltemp < -MAXPHASE) - time_offset = -(MAXPHASE << SHIFT_UPDATE); - else - time_offset = ltemp << SHIFT_UPDATE; - - /* - * Select whether the frequency is to be controlled - * and in which mode (PLL or FLL). Clamp to the operating - * range. Ugly multiply/divide should be replaced someday. - */ - - if (time_status & STA_FREQHOLD || time_reftime == 0) - time_reftime = xtime.tv_sec; - mtemp = xtime.tv_sec - time_reftime; - time_reftime = xtime.tv_sec; - if (time_status & STA_FLL) { - if (mtemp >= MINSEC) { - ltemp = (time_offset / mtemp) << (SHIFT_USEC - - SHIFT_UPDATE); - time_freq += shift_right(ltemp, SHIFT_KH); - } else /* calibration interval too short (p. 12) */ - result = TIME_ERROR; - } else { /* PLL mode */ - if (mtemp < MAXSEC) { - ltemp *= mtemp; - time_freq += shift_right(ltemp,(time_constant + - time_constant + - SHIFT_KF - SHIFT_USEC)); - } else /* calibration interval too long (p. 12) */ - result = TIME_ERROR; - } - time_freq = min(time_freq, time_tolerance); - time_freq = max(time_freq, -time_tolerance); - } /* STA_PLL */ - } /* txc->modes & ADJ_OFFSET */ - if (txc->modes & ADJ_TICK) { - tick_usec = txc->tick; - tick_nsec = TICK_USEC_TO_NSEC(tick_usec); - } - } /* txc->modes */ -leave: if ((time_status & (STA_UNSYNC|STA_CLOCKERR)) != 0) - result = TIME_ERROR; - - if ((txc->modes & ADJ_OFFSET_SINGLESHOT) == ADJ_OFFSET_SINGLESHOT) - txc->offset = save_adjust; - else { - txc->offset = shift_right(time_offset, SHIFT_UPDATE); - } - txc->freq = time_freq; - txc->maxerror = time_maxerror; - txc->esterror = time_esterror; - txc->status = time_status; - txc->constant = time_constant; - txc->precision = time_precision; - txc->tolerance = time_tolerance; - txc->tick = tick_usec; - - /* PPS is not implemented, so these are zero */ - txc->ppsfreq = 0; - txc->jitter = 0; - txc->shift = 0; - txc->stabil = 0; - txc->jitcnt = 0; - txc->calcnt = 0; - txc->errcnt = 0; - txc->stbcnt = 0; - write_sequnlock_irq(&xtime_lock); - do_gettimeofday(&txc->time); - notify_arch_cmos_timer(); - return(result); -} - asmlinkage long sys_adjtimex(struct timex __user *txc_p) { struct timex txc; /* Local copy of parameter */ @@ -523,6 +350,7 @@ EXPORT_SYMBOL(do_gettimeofday); #else +#ifndef CONFIG_GENERIC_TIME /* * Simulate gettimeofday using do_gettimeofday which only allows a timeval * and therefore only yields usec accuracy @@ -537,6 +365,7 @@ void getnstimeofday(struct timespec *tv) } EXPORT_SYMBOL_GPL(getnstimeofday); #endif +#endif /* Converts Gregorian date to seconds since 1970-01-01 00:00:00. * Assumes input in normal date format, i.e. 1980-12-31 23:59:59 @@ -641,6 +470,260 @@ struct timeval ns_to_timeval(const s64 nsec) return tv; } +/* + * Convert jiffies to milliseconds and back. + * + * Avoid unnecessary multiplications/divisions in the + * two most common HZ cases: + */ +unsigned int jiffies_to_msecs(const unsigned long j) +{ +#if HZ <= MSEC_PER_SEC && !(MSEC_PER_SEC % HZ) + return (MSEC_PER_SEC / HZ) * j; +#elif HZ > MSEC_PER_SEC && !(HZ % MSEC_PER_SEC) + return (j + (HZ / MSEC_PER_SEC) - 1)/(HZ / MSEC_PER_SEC); +#else + return (j * MSEC_PER_SEC) / HZ; +#endif +} +EXPORT_SYMBOL(jiffies_to_msecs); + +unsigned int jiffies_to_usecs(const unsigned long j) +{ +#if HZ <= USEC_PER_SEC && !(USEC_PER_SEC % HZ) + return (USEC_PER_SEC / HZ) * j; +#elif HZ > USEC_PER_SEC && !(HZ % USEC_PER_SEC) + return (j + (HZ / USEC_PER_SEC) - 1)/(HZ / USEC_PER_SEC); +#else + return (j * USEC_PER_SEC) / HZ; +#endif +} +EXPORT_SYMBOL(jiffies_to_usecs); + +/* + * When we convert to jiffies then we interpret incoming values + * the following way: + * + * - negative values mean 'infinite timeout' (MAX_JIFFY_OFFSET) + * + * - 'too large' values [that would result in larger than + * MAX_JIFFY_OFFSET values] mean 'infinite timeout' too. + * + * - all other values are converted to jiffies by either multiplying + * the input value by a factor or dividing it with a factor + * + * We must also be careful about 32-bit overflows. + */ +unsigned long msecs_to_jiffies(const unsigned int m) +{ + /* + * Negative value, means infinite timeout: + */ + if ((int)m < 0) + return MAX_JIFFY_OFFSET; + +#if HZ <= MSEC_PER_SEC && !(MSEC_PER_SEC % HZ) + /* + * HZ is equal to or smaller than 1000, and 1000 is a nice + * round multiple of HZ, divide with the factor between them, + * but round upwards: + */ + return (m + (MSEC_PER_SEC / HZ) - 1) / (MSEC_PER_SEC / HZ); +#elif HZ > MSEC_PER_SEC && !(HZ % MSEC_PER_SEC) + /* + * HZ is larger than 1000, and HZ is a nice round multiple of + * 1000 - simply multiply with the factor between them. + * + * But first make sure the multiplication result cannot + * overflow: + */ + if (m > jiffies_to_msecs(MAX_JIFFY_OFFSET)) + return MAX_JIFFY_OFFSET; + + return m * (HZ / MSEC_PER_SEC); +#else + /* + * Generic case - multiply, round and divide. But first + * check that if we are doing a net multiplication, that + * we wouldnt overflow: + */ + if (HZ > MSEC_PER_SEC && m > jiffies_to_msecs(MAX_JIFFY_OFFSET)) + return MAX_JIFFY_OFFSET; + + return (m * HZ + MSEC_PER_SEC - 1) / MSEC_PER_SEC; +#endif +} +EXPORT_SYMBOL(msecs_to_jiffies); + +unsigned long usecs_to_jiffies(const unsigned int u) +{ + if (u > jiffies_to_usecs(MAX_JIFFY_OFFSET)) + return MAX_JIFFY_OFFSET; +#if HZ <= USEC_PER_SEC && !(USEC_PER_SEC % HZ) + return (u + (USEC_PER_SEC / HZ) - 1) / (USEC_PER_SEC / HZ); +#elif HZ > USEC_PER_SEC && !(HZ % USEC_PER_SEC) + return u * (HZ / USEC_PER_SEC); +#else + return (u * HZ + USEC_PER_SEC - 1) / USEC_PER_SEC; +#endif +} +EXPORT_SYMBOL(usecs_to_jiffies); + +/* + * The TICK_NSEC - 1 rounds up the value to the next resolution. Note + * that a remainder subtract here would not do the right thing as the + * resolution values don't fall on second boundries. I.e. the line: + * nsec -= nsec % TICK_NSEC; is NOT a correct resolution rounding. + * + * Rather, we just shift the bits off the right. + * + * The >> (NSEC_JIFFIE_SC - SEC_JIFFIE_SC) converts the scaled nsec + * value to a scaled second value. + */ +unsigned long +timespec_to_jiffies(const struct timespec *value) +{ + unsigned long sec = value->tv_sec; + long nsec = value->tv_nsec + TICK_NSEC - 1; + + if (sec >= MAX_SEC_IN_JIFFIES){ + sec = MAX_SEC_IN_JIFFIES; + nsec = 0; + } + return (((u64)sec * SEC_CONVERSION) + + (((u64)nsec * NSEC_CONVERSION) >> + (NSEC_JIFFIE_SC - SEC_JIFFIE_SC))) >> SEC_JIFFIE_SC; + +} +EXPORT_SYMBOL(timespec_to_jiffies); + +void +jiffies_to_timespec(const unsigned long jiffies, struct timespec *value) +{ + /* + * Convert jiffies to nanoseconds and separate with + * one divide. + */ + u64 nsec = (u64)jiffies * TICK_NSEC; + value->tv_sec = div_long_long_rem(nsec, NSEC_PER_SEC, &value->tv_nsec); +} +EXPORT_SYMBOL(jiffies_to_timespec); + +/* Same for "timeval" + * + * Well, almost. The problem here is that the real system resolution is + * in nanoseconds and the value being converted is in micro seconds. + * Also for some machines (those that use HZ = 1024, in-particular), + * there is a LARGE error in the tick size in microseconds. + + * The solution we use is to do the rounding AFTER we convert the + * microsecond part. Thus the USEC_ROUND, the bits to be shifted off. + * Instruction wise, this should cost only an additional add with carry + * instruction above the way it was done above. + */ +unsigned long +timeval_to_jiffies(const struct timeval *value) +{ + unsigned long sec = value->tv_sec; + long usec = value->tv_usec; + + if (sec >= MAX_SEC_IN_JIFFIES){ + sec = MAX_SEC_IN_JIFFIES; + usec = 0; + } + return (((u64)sec * SEC_CONVERSION) + + (((u64)usec * USEC_CONVERSION + USEC_ROUND) >> + (USEC_JIFFIE_SC - SEC_JIFFIE_SC))) >> SEC_JIFFIE_SC; +} + +void jiffies_to_timeval(const unsigned long jiffies, struct timeval *value) +{ + /* + * Convert jiffies to nanoseconds and separate with + * one divide. + */ + u64 nsec = (u64)jiffies * TICK_NSEC; + long tv_usec; + + value->tv_sec = div_long_long_rem(nsec, NSEC_PER_SEC, &tv_usec); + tv_usec /= NSEC_PER_USEC; + value->tv_usec = tv_usec; +} + +/* + * Convert jiffies/jiffies_64 to clock_t and back. + */ +clock_t jiffies_to_clock_t(long x) +{ +#if (TICK_NSEC % (NSEC_PER_SEC / USER_HZ)) == 0 + return x / (HZ / USER_HZ); +#else + u64 tmp = (u64)x * TICK_NSEC; + do_div(tmp, (NSEC_PER_SEC / USER_HZ)); + return (long)tmp; +#endif +} +EXPORT_SYMBOL(jiffies_to_clock_t); + +unsigned long clock_t_to_jiffies(unsigned long x) +{ +#if (HZ % USER_HZ)==0 + if (x >= ~0UL / (HZ / USER_HZ)) + return ~0UL; + return x * (HZ / USER_HZ); +#else + u64 jif; + + /* Don't worry about loss of precision here .. */ + if (x >= ~0UL / HZ * USER_HZ) + return ~0UL; + + /* .. but do try to contain it here */ + jif = x * (u64) HZ; + do_div(jif, USER_HZ); + return jif; +#endif +} +EXPORT_SYMBOL(clock_t_to_jiffies); + +u64 jiffies_64_to_clock_t(u64 x) +{ +#if (TICK_NSEC % (NSEC_PER_SEC / USER_HZ)) == 0 + do_div(x, HZ / USER_HZ); +#else + /* + * There are better ways that don't overflow early, + * but even this doesn't overflow in hundreds of years + * in 64 bits, so.. + */ + x *= TICK_NSEC; + do_div(x, (NSEC_PER_SEC / USER_HZ)); +#endif + return x; +} + +EXPORT_SYMBOL(jiffies_64_to_clock_t); + +u64 nsec_to_clock_t(u64 x) +{ +#if (NSEC_PER_SEC % USER_HZ) == 0 + do_div(x, (NSEC_PER_SEC / USER_HZ)); +#elif (USER_HZ % 512) == 0 + x *= USER_HZ/512; + do_div(x, (NSEC_PER_SEC / 512)); +#else + /* + * max relative error 5.7e-8 (1.8s per year) for USER_HZ <= 1024, + * overflow after 64.99 years. + * exact for HZ=60, 72, 90, 120, 144, 180, 300, 600, 900, ... + */ + x *= 9; + do_div(x, (unsigned long)((9ull * NSEC_PER_SEC + (USER_HZ/2)) / + USER_HZ)); +#endif + return x; +} + #if (BITS_PER_LONG < 64) u64 get_jiffies_64(void) {