diff options
Diffstat (limited to 'kernel/timer.c')
| -rw-r--r-- | kernel/timer.c | 53 |
1 files changed, 11 insertions, 42 deletions
diff --git a/kernel/timer.c b/kernel/timer.c index 6ed1a82..6b94adb 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -703,23 +703,13 @@ static void second_overflow(void) * the adjustment over not more than the number of * seconds between updates. */ - if (time_offset < 0) { - ltemp = -time_offset; - if (!(time_status & STA_FLL)) - ltemp >>= SHIFT_KG + time_constant; - if (ltemp > (MAXPHASE / MINSEC) << SHIFT_UPDATE) - ltemp = (MAXPHASE / MINSEC) << SHIFT_UPDATE; - time_offset += ltemp; - time_adj = -ltemp << (SHIFT_SCALE - SHIFT_HZ - SHIFT_UPDATE); - } else { ltemp = time_offset; if (!(time_status & STA_FLL)) - ltemp >>= SHIFT_KG + time_constant; - if (ltemp > (MAXPHASE / MINSEC) << SHIFT_UPDATE) - ltemp = (MAXPHASE / MINSEC) << SHIFT_UPDATE; + ltemp = shift_right(ltemp, SHIFT_KG + time_constant); + ltemp = min(ltemp, (MAXPHASE / MINSEC) << SHIFT_UPDATE); + ltemp = max(ltemp, -(MAXPHASE / MINSEC) << SHIFT_UPDATE); time_offset -= ltemp; time_adj = ltemp << (SHIFT_SCALE - SHIFT_HZ - SHIFT_UPDATE); - } /* * Compute the frequency estimate and additional phase @@ -736,39 +726,25 @@ static void second_overflow(void) STA_PPSWANDER | STA_PPSERROR); } ltemp = time_freq + pps_freq; - if (ltemp < 0) - time_adj -= -ltemp >> - (SHIFT_USEC + SHIFT_HZ - SHIFT_SCALE); - else - time_adj += ltemp >> - (SHIFT_USEC + SHIFT_HZ - SHIFT_SCALE); + time_adj += shift_right(ltemp,(SHIFT_USEC + SHIFT_HZ - SHIFT_SCALE)); #if HZ == 100 /* Compensate for (HZ==100) != (1 << SHIFT_HZ). * Add 25% and 3.125% to get 128.125; => only 0.125% error (p. 14) */ - if (time_adj < 0) - time_adj -= (-time_adj >> 2) + (-time_adj >> 5); - else - time_adj += (time_adj >> 2) + (time_adj >> 5); + time_adj += shift_right(time_adj, 2) + shift_right(time_adj, 5); #endif #if HZ == 250 /* Compensate for (HZ==250) != (1 << SHIFT_HZ). * Add 1.5625% and 0.78125% to get 255.85938; => only 0.05% error (p. 14) */ - if (time_adj < 0) - time_adj -= (-time_adj >> 6) + (-time_adj >> 7); - else - time_adj += (time_adj >> 6) + (time_adj >> 7); + time_adj += shift_right(time_adj, 6) + shift_right(time_adj, 7); #endif #if HZ == 1000 /* Compensate for (HZ==1000) != (1 << SHIFT_HZ). * Add 1.5625% and 0.78125% to get 1023.4375; => only 0.05% error (p. 14) */ - if (time_adj < 0) - time_adj -= (-time_adj >> 6) + (-time_adj >> 7); - else - time_adj += (time_adj >> 6) + (time_adj >> 7); + time_adj += shift_right(time_adj, 6) + shift_right(time_adj, 7); #endif } @@ -787,10 +763,8 @@ static void update_wall_time_one_tick(void) * Limit the amount of the step to be in the range * -tickadj .. +tickadj */ - if (time_adjust > tickadj) - time_adjust_step = tickadj; - else if (time_adjust < -tickadj) - time_adjust_step = -tickadj; + time_adjust_step = min(time_adjust_step, (long)tickadj); + time_adjust_step = max(time_adjust_step, (long)-tickadj); /* Reduce by this step the amount of time left */ time_adjust -= time_adjust_step; @@ -801,13 +775,8 @@ static void update_wall_time_one_tick(void) * advance the tick more. */ time_phase += time_adj; - if (time_phase <= -FINENSEC) { - long ltemp = -time_phase >> (SHIFT_SCALE - 10); - time_phase += ltemp << (SHIFT_SCALE - 10); - delta_nsec -= ltemp; - } - else if (time_phase >= FINENSEC) { - long ltemp = time_phase >> (SHIFT_SCALE - 10); + if ((time_phase >= FINENSEC) || (time_phase <= -FINENSEC)) { + long ltemp = shift_right(time_phase, (SHIFT_SCALE - 10)); time_phase -= ltemp << (SHIFT_SCALE - 10); delta_nsec += ltemp; } |
