| 1 | |
| 2 | * kernel/sched/proc.c
|
| 3 | *
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| 4 | * Kernel load calculations, forked from sched/core.c
|
| 5 |
|
| 6 |
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| 7 | #include <linux/export.h>
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| 8 |
|
| 9 | #include "sched.h"
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| 10 |
|
| 11 | unsigned long this_cpu_load(void)
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| 12 | {
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| 13 | struct rq *this = this_rq();
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| 14 | return this->cpu_load[0];
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| 15 | }
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| 16 |
|
| 17 |
|
| 18 | |
| 19 | * Global load-average calculations
|
| 20 | *
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| 21 | * We take a distributed and async approach to calculating the global load-avg
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| 22 | * in order to minimize overhead.
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| 23 | *
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| 24 | * The global load average is an exponentially decaying average of nr_running +
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| 25 | * nr_uninterruptible.
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| 26 | *
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| 27 | * Once every LOAD_FREQ:
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| 28 | *
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| 29 | * nr_active = 0;
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| 30 | * for_each_possible_cpu(cpu)
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| 31 | * nr_active += cpu_of(cpu)->nr_running + cpu_of(cpu)->nr_uninterruptible;
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| 32 | *
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| 33 | * avenrun[n] = avenrun[0] * exp_n + nr_active * (1 - exp_n)
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| 34 | *
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| 35 | * Due to a number of reasons the above turns in the mess below:
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| 36 | *
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| 37 | * - for_each_possible_cpu() is prohibitively expensive on machines with
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| 38 | * serious number of cpus, therefore we need to take a distributed approach
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| 39 | * to calculating nr_active.
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| 40 | *
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| 41 | * \Sum_i x_i(t) = \Sum_i x_i(t) - x_i(t_0) | x_i(t_0) := 0
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| 42 | * = \Sum_i { \Sum_j=1 x_i(t_j) - x_i(t_j-1) }
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| 43 | *
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| 44 | * So assuming nr_active := 0 when we start out -- true per definition, we
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| 45 | * can simply take per-cpu deltas and fold those into a global accumulate
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| 46 | * to obtain the same result. See calc_load_fold_active().
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| 47 | *
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| 48 | * Furthermore, in order to avoid synchronizing all per-cpu delta folding
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| 49 | * across the machine, we assume 10 ticks is sufficient time for every
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| 50 | * cpu to have completed this task.
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| 51 | *
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| 52 | * This places an upper-bound on the IRQ-off latency of the machine. Then
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| 53 | * again, being late doesn't loose the delta, just wrecks the sample.
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| 54 | *
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| 55 | * - cpu_rq()->nr_uninterruptible isn't accurately tracked per-cpu because
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| 56 | * this would add another cross-cpu cacheline miss and atomic operation
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| 57 | * to the wakeup path. Instead we increment on whatever cpu the task ran
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| 58 | * when it went into uninterruptible state and decrement on whatever cpu
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| 59 | * did the wakeup. This means that only the sum of nr_uninterruptible over
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| 60 | * all cpus yields the correct result.
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| 61 | *
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| 62 | * This covers the NO_HZ=n code, for extra head-aches, see the comment below.
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| 63 |
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| 64 |
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| 65 |
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| 66 | atomic_long_t calc_load_tasks;
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| 67 | unsigned long calc_load_update;
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| 68 | unsigned long avenrun[3];
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| 69 | EXPORT_SYMBOL(avenrun);
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| 70 |
|
| 71 | |
| 72 | * get_avenrun - get the load average array
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| 73 | * @loads: pointer to dest load array
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| 74 | * @offset: offset to add
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| 75 | * @shift: shift count to shift the result left
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| 76 | *
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| 77 | * These values are estimates at best, so no need for locking.
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| 78 |
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| 79 | void get_avenrun(unsigned long *loads, unsigned long offset, int shift)
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| 80 | {
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| 81 | loads[0] = (avenrun[0] + offset) << shift;
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| 82 | loads[1] = (avenrun[1] + offset) << shift;
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| 83 | loads[2] = (avenrun[2] + offset) << shift;
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| 84 | }
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| 85 |
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| 86 | long calc_load_fold_active(struct rq *this_rq)
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| 87 | {
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| 88 | long nr_active, delta = 0;
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| 89 |
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| 90 | nr_active = this_rq->nr_running;
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| 91 | nr_active += (long) this_rq->nr_uninterruptible;
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| 92 |
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| 93 | if (nr_active != this_rq->calc_load_active) {
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| 94 | delta = nr_active - this_rq->calc_load_active;
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| 95 | this_rq->calc_load_active = nr_active;
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| 96 | }
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| 97 |
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| 98 | return delta;
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| 99 | }
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| 100 |
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| 101 | |
| 102 | * a1 = a0 * e + a * (1 - e)
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| 103 |
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| 104 | static unsigned long
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| 105 | calc_load(unsigned long load, unsigned long exp, unsigned long active)
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| 106 | {
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| 107 | load *= exp;
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| 108 | load += active * (FIXED_1 - exp);
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| 109 | load += 1UL << (FSHIFT - 1);
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| 110 | return load >> FSHIFT;
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| 111 | }
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| 112 |
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| 113 | #ifdef CONFIG_NO_HZ_COMMON
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| 114 | |
| 115 | * Handle NO_HZ for the global load-average.
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| 116 | *
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| 117 | * Since the above described distributed algorithm to compute the global
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| 118 | * load-average relies on per-cpu sampling from the tick, it is affected by
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| 119 | * NO_HZ.
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| 120 | *
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| 121 | * The basic idea is to fold the nr_active delta into a global idle-delta upon
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| 122 | * entering NO_HZ state such that we can include this as an 'extra' cpu delta
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| 123 | * when we read the global state.
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| 124 | *
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| 125 | * Obviously reality has to ruin such a delightfully simple scheme:
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| 126 | *
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| 127 | * - When we go NO_HZ idle during the window, we can negate our sample
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| 128 | * contribution, causing under-accounting.
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| 129 | *
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| 130 | * We avoid this by keeping two idle-delta counters and flipping them
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| 131 | * when the window starts, thus separating old and new NO_HZ load.
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| 132 | *
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| 133 | * The only trick is the slight shift in index flip for read vs write.
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| 134 | *
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| 135 | * 0s 5s 10s 15s
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| 136 | * +10 +10 +10 +10
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| 137 | * |-|-----------|-|-----------|-|-----------|-|
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| 138 | * r:0 0 1 1 0 0 1 1 0
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| 139 | * w:0 1 1 0 0 1 1 0 0
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| 140 | *
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| 141 | * This ensures we'll fold the old idle contribution in this window while
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| 142 | * accumlating the new one.
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| 143 | *
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| 144 | * - When we wake up from NO_HZ idle during the window, we push up our
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| 145 | * contribution, since we effectively move our sample point to a known
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| 146 | * busy state.
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| 147 | *
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| 148 | * This is solved by pushing the window forward, and thus skipping the
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| 149 | * sample, for this cpu (effectively using the idle-delta for this cpu which
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| 150 | * was in effect at the time the window opened). This also solves the issue
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| 151 | * of having to deal with a cpu having been in NOHZ idle for multiple
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| 152 | * LOAD_FREQ intervals.
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| 153 | *
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| 154 | * When making the ILB scale, we should try to pull this in as well.
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| 155 |
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| 156 | static atomic_long_t calc_load_idle[2];
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| 157 | static int calc_load_idx;
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| 158 |
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| 159 | static inline int calc_load_write_idx(void)
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| 160 | {
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| 161 | int idx = calc_load_idx;
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| 162 |
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| 163 | |
| 164 | * See calc_global_nohz(), if we observe the new index, we also
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| 165 | * need to observe the new update time.
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| 166 |
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| 167 | smp_rmb();
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| 168 |
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| 169 | |
| 170 | * If the folding window started, make sure we start writing in the
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| 171 | * next idle-delta.
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| 172 |
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| 173 | if (!time_before(jiffies, calc_load_update))
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| 174 | idx++;
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| 175 |
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| 176 | return idx & 1;
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| 177 | }
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| 178 |
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| 179 | static inline int calc_load_read_idx(void)
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| 180 | {
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| 181 | return calc_load_idx & 1;
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| 182 | }
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| 183 |
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| 184 | void calc_load_enter_idle(void)
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| 185 | {
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| 186 | struct rq *this_rq = this_rq();
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| 187 | long delta;
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| 188 |
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| 189 | |
| 190 | * We're going into NOHZ mode, if there's any pending delta, fold it
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| 191 | * into the pending idle delta.
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| 192 |
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| 193 | delta = calc_load_fold_active(this_rq);
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| 194 | if (delta) {
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| 195 | int idx = calc_load_write_idx();
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| 196 | atomic_long_add(delta, &calc_load_idle[idx]);
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| 197 | }
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| 198 | }
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| 199 |
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| 200 | void calc_load_exit_idle(void)
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| 201 | {
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| 202 | struct rq *this_rq = this_rq();
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| 203 |
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| 204 | |
| 205 | * If we're still before the sample window, we're done.
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| 206 |
|
| 207 | if (time_before(jiffies, this_rq->calc_load_update))
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| 208 | return;
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| 209 |
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| 210 | |
| 211 | * We woke inside or after the sample window, this means we're already
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| 212 | * accounted through the nohz accounting, so skip the entire deal and
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| 213 | * sync up for the next window.
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| 214 |
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| 215 | this_rq->calc_load_update = calc_load_update;
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| 216 | if (time_before(jiffies, this_rq->calc_load_update + 10))
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| 217 | this_rq->calc_load_update += LOAD_FREQ;
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| 218 | }
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| 219 |
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| 220 | static long calc_load_fold_idle(void)
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| 221 | {
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| 222 | int idx = calc_load_read_idx();
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| 223 | long delta = 0;
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| 224 |
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| 225 | if (atomic_long_read(&calc_load_idle[idx]))
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| 226 | delta = atomic_long_xchg(&calc_load_idle[idx], 0);
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| 227 |
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| 228 | return delta;
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| 229 | }
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| 230 |
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| 231 | |
| 232 | * fixed_power_int - compute: x^n, in O(log n) time
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| 233 | *
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| 234 | * @x: base of the power
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| 235 | * @frac_bits: fractional bits of @x
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| 236 | * @n: power to raise @x to.
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| 237 | *
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| 238 | * By exploiting the relation between the definition of the natural power
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| 239 | * function: x^n := x*x*...*x (x multiplied by itself for n times), and
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| 240 | * the binary encoding of numbers used by computers: n := \Sum n_i * 2^i,
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| 241 | * (where: n_i \elem {0, 1}, the binary vector representing n),
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| 242 | * we find: x^n := x^(\Sum n_i * 2^i) := \Prod x^(n_i * 2^i), which is
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| 243 | * of course trivially computable in O(log_2 n), the length of our binary
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| 244 | * vector.
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| 245 |
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| 246 | static unsigned long
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| 247 | fixed_power_int(unsigned long x, unsigned int frac_bits, unsigned int n)
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| 248 | {
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| 249 | unsigned long result = 1UL << frac_bits;
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| 250 |
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| 251 | if (n) for (;;) {
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| 252 | if (n & 1) {
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| 253 | result *= x;
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| 254 | result += 1UL << (frac_bits - 1);
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| 255 | result >>= frac_bits;
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| 256 | }
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| 257 | n >>= 1;
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| 258 | if (!n)
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| 259 | break;
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| 260 | x *= x;
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| 261 | x += 1UL << (frac_bits - 1);
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| 262 | x >>= frac_bits;
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| 263 | }
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| 264 |
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| 265 | return result;
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| 266 | }
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| 267 |
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| 268 | |
| 269 | * a1 = a0 * e + a * (1 - e)
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| 270 | *
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| 271 | * a2 = a1 * e + a * (1 - e)
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| 272 | * = (a0 * e + a * (1 - e)) * e + a * (1 - e)
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| 273 | * = a0 * e^2 + a * (1 - e) * (1 + e)
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| 274 | *
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| 275 | * a3 = a2 * e + a * (1 - e)
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| 276 | * = (a0 * e^2 + a * (1 - e) * (1 + e)) * e + a * (1 - e)
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| 277 | * = a0 * e^3 + a * (1 - e) * (1 + e + e^2)
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| 278 | *
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| 279 | * ...
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| 280 | *
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| 281 | * an = a0 * e^n + a * (1 - e) * (1 + e + ... + e^n-1) [1]
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| 282 | * = a0 * e^n + a * (1 - e) * (1 - e^n)/(1 - e)
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| 283 | * = a0 * e^n + a * (1 - e^n)
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| 284 | *
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| 285 | * [1] application of the geometric series:
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| 286 | *
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| 287 | * n 1 - x^(n+1)
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| 288 | * S_n := \Sum x^i = -------------
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| 289 | * i=0 1 - x
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| 290 |
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| 291 | static unsigned long
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| 292 | calc_load_n(unsigned long load, unsigned long exp,
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| 293 | unsigned long active, unsigned int n)
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| 294 | {
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| 295 |
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| 296 | return calc_load(load, fixed_power_int(exp, FSHIFT, n), active);
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| 297 | }
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| 298 |
|
| 299 | |
| 300 | * NO_HZ can leave us missing all per-cpu ticks calling
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| 301 | * calc_load_account_active(), but since an idle CPU folds its delta into
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| 302 | * calc_load_tasks_idle per calc_load_account_idle(), all we need to do is fold
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| 303 | * in the pending idle delta if our idle period crossed a load cycle boundary.
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| 304 | *
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| 305 | * Once we've updated the global active value, we need to apply the exponential
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| 306 | * weights adjusted to the number of cycles missed.
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| 307 |
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| 308 | static void calc_global_nohz(void)
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| 309 | {
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| 310 | long delta, active, n;
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| 311 |
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| 312 | if (!time_before(jiffies, calc_load_update + 10)) {
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| 313 | |
| 314 | * Catch-up, fold however many we are behind still
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| 315 |
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| 316 | delta = jiffies - calc_load_update - 10;
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| 317 | n = 1 + (delta / LOAD_FREQ);
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| 318 |
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| 319 | active = atomic_long_read(&calc_load_tasks);
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| 320 | active = active > 0 ? active * FIXED_1 : 0;
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| 321 |
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| 322 | avenrun[0] = calc_load_n(avenrun[0], EXP_1, active, n);
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| 323 | avenrun[1] = calc_load_n(avenrun[1], EXP_5, active, n);
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| 324 | avenrun[2] = calc_load_n(avenrun[2], EXP_15, active, n);
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| 325 |
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| 326 | calc_load_update += n * LOAD_FREQ;
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| 327 | }
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| 328 |
|
| 329 | |
| 330 | * Flip the idle index...
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| 331 | *
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| 332 | * Make sure we first write the new time then flip the index, so that
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| 333 | * calc_load_write_idx() will see the new time when it reads the new
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| 334 | * index, this avoids a double flip messing things up.
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| 335 |
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| 336 | smp_wmb();
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| 337 | calc_load_idx++;
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| 338 | }
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| 339 | #else
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| 340 |
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| 341 | static inline long calc_load_fold_idle(void) { return 0; }
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| 342 | static inline void calc_global_nohz(void) { }
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| 343 |
|
| 344 | #endif
|
| 345 |
|
| 346 | |
| 347 | * calc_load - update the avenrun load estimates 10 ticks after the
|
| 348 | * CPUs have updated calc_load_tasks.
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| 349 |
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| 350 | void calc_global_load(unsigned long ticks)
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| 351 | {
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| 352 | long active, delta;
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| 353 |
|
| 354 | if (time_before(jiffies, calc_load_update + 10))
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| 355 | return;
|
| 356 |
|
| 357 | |
| 358 | * Fold the 'old' idle-delta to include all NO_HZ cpus.
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| 359 |
|
| 360 | delta = calc_load_fold_idle();
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| 361 | if (delta)
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| 362 | atomic_long_add(delta, &calc_load_tasks);
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| 363 |
|
| 364 | active = atomic_long_read(&calc_load_tasks);
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| 365 | active = active > 0 ? active * FIXED_1 : 0;
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| 366 |
|
| 367 | avenrun[0] = calc_load(avenrun[0], EXP_1, active);
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| 368 | avenrun[1] = calc_load(avenrun[1], EXP_5, active);
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| 369 | avenrun[2] = calc_load(avenrun[2], EXP_15, active);
|
| 370 |
|
| 371 | calc_load_update += LOAD_FREQ;
|
| 372 |
|
| 373 | |
| 374 | * In case we idled for multiple LOAD_FREQ intervals, catch up in bulk.
|
| 375 |
|
| 376 | calc_global_nohz();
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| 377 | }
|
| 378 |
|
| 379 | |
| 380 | * Called from update_cpu_load() to periodically update this CPU's
|
| 381 | * active count.
|
| 382 |
|
| 383 | static void calc_load_account_active(struct rq *this_rq)
|
| 384 | {
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| 385 | long delta;
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| 386 |
|
| 387 | if (time_before(jiffies, this_rq->calc_load_update))
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| 388 | return;
|
| 389 |
|
| 390 | delta = calc_load_fold_active(this_rq);
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| 391 | if (delta)
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| 392 | atomic_long_add(delta, &calc_load_tasks);
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| 393 |
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| 394 | this_rq->calc_load_update += LOAD_FREQ;
|
| 395 | }
|
| 396 |
|
| 397 | |
| 398 | * End of global load-average stuff
|
| 399 |
|
| 400 |
|
| 401 | |
| 402 | * The exact cpuload at various idx values, calculated at every tick would be
|
| 403 | * load = (2^idx - 1) / 2^idx * load + 1 / 2^idx * cur_load
|
| 404 | *
|
| 405 | * If a cpu misses updates for n-1 ticks (as it was idle) and update gets called
|
| 406 | * on nth tick when cpu may be busy, then we have:
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| 407 | * load = ((2^idx - 1) / 2^idx)^(n-1) * load
|
| 408 | * load = (2^idx - 1) / 2^idx) * load + 1 / 2^idx * cur_load
|
| 409 | *
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| 410 | * decay_load_missed() below does efficient calculation of
|
| 411 | * load = ((2^idx - 1) / 2^idx)^(n-1) * load
|
| 412 | * avoiding 0..n-1 loop doing load = ((2^idx - 1) / 2^idx) * load
|
| 413 | *
|
| 414 | * The calculation is approximated on a 128 point scale.
|
| 415 | * degrade_zero_ticks is the number of ticks after which load at any
|
| 416 | * particular idx is approximated to be zero.
|
| 417 | * degrade_factor is a precomputed table, a row for each load idx.
|
| 418 | * Each column corresponds to degradation factor for a power of two ticks,
|
| 419 | * based on 128 point scale.
|
| 420 | * Example:
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| 421 | * row 2, col 3 (=12) says that the degradation at load idx 2 after
|
| 422 | * 8 ticks is 12/128 (which is an approximation of exact factor 3^8/4^8).
|
| 423 | *
|
| 424 | * With this power of 2 load factors, we can degrade the load n times
|
| 425 | * by looking at 1 bits in n and doing as many mult/shift instead of
|
| 426 | * n mult/shifts needed by the exact degradation.
|
| 427 |
|
| 428 | #define DEGRADE_SHIFT 7
|
| 429 | static const unsigned char
|
| 430 | degrade_zero_ticks[CPU_LOAD_IDX_MAX] = {0, 8, 32, 64, 128};
|
| 431 | static const unsigned char
|
| 432 | degrade_factor[CPU_LOAD_IDX_MAX][DEGRADE_SHIFT + 1] = {
|
| 433 | {0, 0, 0, 0, 0, 0, 0, 0},
|
| 434 | {64, 32, 8, 0, 0, 0, 0, 0},
|
| 435 | {96, 72, 40, 12, 1, 0, 0},
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| 436 | {112, 98, 75, 43, 15, 1, 0},
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| 437 | {120, 112, 98, 76, 45, 16, 2} };
|
| 438 |
|
| 439 | |
| 440 | * Update cpu_load for any missed ticks, due to tickless idle. The backlog
|
| 441 | * would be when CPU is idle and so we just decay the old load without
|
| 442 | * adding any new load.
|
| 443 |
|
| 444 | static unsigned long
|
| 445 | decay_load_missed(unsigned long load, unsigned long missed_updates, int idx)
|
| 446 | {
|
| 447 | int j = 0;
|
| 448 |
|
| 449 | if (!missed_updates)
|
| 450 | return load;
|
| 451 |
|
| 452 | if (missed_updates >= degrade_zero_ticks[idx])
|
| 453 | return 0;
|
| 454 |
|
| 455 | if (idx == 1)
|
| 456 | return load >> missed_updates;
|
| 457 |
|
| 458 | while (missed_updates) {
|
| 459 | if (missed_updates % 2)
|
| 460 | load = (load * degrade_factor[idx][j]) >> DEGRADE_SHIFT;
|
| 461 |
|
| 462 | missed_updates >>= 1;
|
| 463 | j++;
|
| 464 | }
|
| 465 | return load;
|
| 466 | }
|
| 467 |
|
| 468 | |
| 469 | * Update rq->cpu_load[] statistics. This function is usually called every
|
| 470 | * scheduler tick (TICK_NSEC). With tickless idle this will not be called
|
| 471 | * every tick. We fix it up based on jiffies.
|
| 472 |
|
| 473 | static void __update_cpu_load(struct rq *this_rq, unsigned long this_load,
|
| 474 | unsigned long pending_updates)
|
| 475 | {
|
| 476 | int i, scale;
|
| 477 |
|
| 478 | this_rq->nr_load_updates++;
|
| 479 |
|
| 480 |
|
| 481 | this_rq->cpu_load[0] = this_load;
|
| 482 | for (i = 1, scale = 2; i < CPU_LOAD_IDX_MAX; i++, scale += scale) {
|
| 483 | unsigned long old_load, new_load;
|
| 484 |
|
| 485 |
|
| 486 |
|
| 487 | old_load = this_rq->cpu_load[i];
|
| 488 | old_load = decay_load_missed(old_load, pending_updates - 1, i);
|
| 489 | new_load = this_load;
|
| 490 | |
| 491 | * Round up the averaging division if load is increasing. This
|
| 492 | * prevents us from getting stuck on 9 if the load is 10, for
|
| 493 | * example.
|
| 494 |
|
| 495 | if (new_load > old_load)
|
| 496 | new_load += scale - 1;
|
| 497 |
|
| 498 | this_rq->cpu_load[i] = (old_load * (scale - 1) + new_load) >> i;
|
| 499 | }
|
| 500 |
|
| 501 | sched_avg_update(this_rq);
|
| 502 | }
|
| 503 |
|
| 504 | #ifdef CONFIG_SMP
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| 505 | static inline unsigned long get_rq_runnable_load(struct rq *rq)
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| 506 | {
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| 507 | return rq->cfs.runnable_load_avg;
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| 508 | }
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| 509 | #else
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| 510 | static inline unsigned long get_rq_runnable_load(struct rq *rq)
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| 511 | {
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| 512 | return rq->load.weight;
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| 513 | }
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| 514 | #endif
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| 515 |
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| 516 | #ifdef CONFIG_NO_HZ_COMMON
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| 517 | |
| 518 | * There is no sane way to deal with nohz on smp when using jiffies because the
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| 519 | * cpu doing the jiffies update might drift wrt the cpu doing the jiffy reading
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| 520 | * causing off-by-one errors in observed deltas; {0,2} instead of {1,1}.
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| 521 | *
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| 522 | * Therefore we cannot use the delta approach from the regular tick since that
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| 523 | * would seriously skew the load calculation. However we'll make do for those
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| 524 | * updates happening while idle (nohz_idle_balance) or coming out of idle
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| 525 | * (tick_nohz_idle_exit).
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| 526 | *
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| 527 | * This means we might still be one tick off for nohz periods.
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| 528 |
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| 529 |
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| 530 | |
| 531 | * Called from nohz_idle_balance() to update the load ratings before doing the
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| 532 | * idle balance.
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| 533 |
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| 534 | void update_idle_cpu_load(struct rq *this_rq)
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| 535 | {
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| 536 | unsigned long curr_jiffies = ACCESS_ONCE(jiffies);
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| 537 | unsigned long load = get_rq_runnable_load(this_rq);
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| 538 | unsigned long pending_updates;
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| 539 |
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| 540 | |
| 541 | * bail if there's load or we're actually up-to-date.
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| 542 |
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| 543 | if (load || curr_jiffies == this_rq->last_load_update_tick)
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| 544 | return;
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| 545 |
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| 546 | pending_updates = curr_jiffies - this_rq->last_load_update_tick;
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| 547 | this_rq->last_load_update_tick = curr_jiffies;
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| 548 |
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| 549 | __update_cpu_load(this_rq, load, pending_updates);
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| 550 | }
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| 551 |
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| 552 | |
| 553 | * Called from tick_nohz_idle_exit() -- try and fix up the ticks we missed.
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| 554 |
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| 555 | void update_cpu_load_nohz(void)
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| 556 | {
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| 557 | struct rq *this_rq = this_rq();
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| 558 | unsigned long curr_jiffies = ACCESS_ONCE(jiffies);
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| 559 | unsigned long pending_updates;
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| 560 |
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| 561 | if (curr_jiffies == this_rq->last_load_update_tick)
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| 562 | return;
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| 563 |
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| 564 | raw_spin_lock(&this_rq->lock);
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| 565 | pending_updates = curr_jiffies - this_rq->last_load_update_tick;
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| 566 | if (pending_updates) {
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| 567 | this_rq->last_load_update_tick = curr_jiffies;
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| 568 | |
| 569 | * We were idle, this means load 0, the current load might be
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| 570 | * !0 due to remote wakeups and the sort.
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| 571 |
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| 572 | __update_cpu_load(this_rq, 0, pending_updates);
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| 573 | }
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| 574 | raw_spin_unlock(&this_rq->lock);
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| 575 | }
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| 576 | #endif
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| 577 |
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| 578 | |
| 579 | * Called from scheduler_tick()
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| 580 |
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| 581 | void update_cpu_load_active(struct rq *this_rq)
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| 582 | {
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| 583 | unsigned long load = get_rq_runnable_load(this_rq);
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| 584 | |
| 585 | * See the mess around update_idle_cpu_load() / update_cpu_load_nohz().
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| 586 |
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| 587 | this_rq->last_load_update_tick = jiffies;
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| 588 | __update_cpu_load(this_rq, load, 1);
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| 589 |
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| 590 | calc_load_account_active(this_rq);
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| 591 | }
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