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-rw-r--r--kernel/sched/fair.c333
1 files changed, 1 insertions, 332 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 08b89ae34233..39ab46cea6c5 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -255,9 +255,6 @@ static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
return cfs_rq->rq;
}
-/* An entity is a task if it doesn't "own" a runqueue */
-#define entity_is_task(se) (!se->my_q)
-
static inline struct task_struct *task_of(struct sched_entity *se)
{
SCHED_WARN_ON(!entity_is_task(se));
@@ -419,7 +416,6 @@ static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
return container_of(cfs_rq, struct rq, cfs);
}
-#define entity_is_task(se) 1
#define for_each_sched_entity(se) \
for (; se; se = NULL)
@@ -692,7 +688,7 @@ static u64 sched_vslice(struct cfs_rq *cfs_rq, struct sched_entity *se)
}
#ifdef CONFIG_SMP
-
+#include "pelt.h"
#include "sched-pelt.h"
static int select_idle_sibling(struct task_struct *p, int prev_cpu, int cpu);
@@ -2751,19 +2747,6 @@ account_entity_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se)
} while (0)
#ifdef CONFIG_SMP
-/*
- * XXX we want to get rid of these helpers and use the full load resolution.
- */
-static inline long se_weight(struct sched_entity *se)
-{
- return scale_load_down(se->load.weight);
-}
-
-static inline long se_runnable(struct sched_entity *se)
-{
- return scale_load_down(se->runnable_weight);
-}
-
static inline void
enqueue_runnable_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
@@ -3064,314 +3047,6 @@ static inline void cfs_rq_util_change(struct cfs_rq *cfs_rq, int flags)
}
#ifdef CONFIG_SMP
-/*
- * Approximate:
- * val * y^n, where y^32 ~= 0.5 (~1 scheduling period)
- */
-static u64 decay_load(u64 val, u64 n)
-{
- unsigned int local_n;
-
- if (unlikely(n > LOAD_AVG_PERIOD * 63))
- return 0;
-
- /* after bounds checking we can collapse to 32-bit */
- local_n = n;
-
- /*
- * As y^PERIOD = 1/2, we can combine
- * y^n = 1/2^(n/PERIOD) * y^(n%PERIOD)
- * With a look-up table which covers y^n (n<PERIOD)
- *
- * To achieve constant time decay_load.
- */
- if (unlikely(local_n >= LOAD_AVG_PERIOD)) {
- val >>= local_n / LOAD_AVG_PERIOD;
- local_n %= LOAD_AVG_PERIOD;
- }
-
- val = mul_u64_u32_shr(val, runnable_avg_yN_inv[local_n], 32);
- return val;
-}
-
-static u32 __accumulate_pelt_segments(u64 periods, u32 d1, u32 d3)
-{
- u32 c1, c2, c3 = d3; /* y^0 == 1 */
-
- /*
- * c1 = d1 y^p
- */
- c1 = decay_load((u64)d1, periods);
-
- /*
- * p-1
- * c2 = 1024 \Sum y^n
- * n=1
- *
- * inf inf
- * = 1024 ( \Sum y^n - \Sum y^n - y^0 )
- * n=0 n=p
- */
- c2 = LOAD_AVG_MAX - decay_load(LOAD_AVG_MAX, periods) - 1024;
-
- return c1 + c2 + c3;
-}
-
-/*
- * Accumulate the three separate parts of the sum; d1 the remainder
- * of the last (incomplete) period, d2 the span of full periods and d3
- * the remainder of the (incomplete) current period.
- *
- * d1 d2 d3
- * ^ ^ ^
- * | | |
- * |<->|<----------------->|<--->|
- * ... |---x---|------| ... |------|-----x (now)
- *
- * p-1
- * u' = (u + d1) y^p + 1024 \Sum y^n + d3 y^0
- * n=1
- *
- * = u y^p + (Step 1)
- *
- * p-1
- * d1 y^p + 1024 \Sum y^n + d3 y^0 (Step 2)
- * n=1
- */
-static __always_inline u32
-accumulate_sum(u64 delta, int cpu, struct sched_avg *sa,
- unsigned long load, unsigned long runnable, int running)
-{
- unsigned long scale_freq, scale_cpu;
- u32 contrib = (u32)delta; /* p == 0 -> delta < 1024 */
- u64 periods;
-
- scale_freq = arch_scale_freq_capacity(cpu);
- scale_cpu = arch_scale_cpu_capacity(NULL, cpu);
-
- delta += sa->period_contrib;
- periods = delta / 1024; /* A period is 1024us (~1ms) */
-
- /*
- * Step 1: decay old *_sum if we crossed period boundaries.
- */
- if (periods) {
- sa->load_sum = decay_load(sa->load_sum, periods);
- sa->runnable_load_sum =
- decay_load(sa->runnable_load_sum, periods);
- sa->util_sum = decay_load((u64)(sa->util_sum), periods);
-
- /*
- * Step 2
- */
- delta %= 1024;
- contrib = __accumulate_pelt_segments(periods,
- 1024 - sa->period_contrib, delta);
- }
- sa->period_contrib = delta;
-
- contrib = cap_scale(contrib, scale_freq);
- if (load)
- sa->load_sum += load * contrib;
- if (runnable)
- sa->runnable_load_sum += runnable * contrib;
- if (running)
- sa->util_sum += contrib * scale_cpu;
-
- return periods;
-}
-
-/*
- * We can represent the historical contribution to runnable average as the
- * coefficients of a geometric series. To do this we sub-divide our runnable
- * history into segments of approximately 1ms (1024us); label the segment that
- * occurred N-ms ago p_N, with p_0 corresponding to the current period, e.g.
- *
- * [<- 1024us ->|<- 1024us ->|<- 1024us ->| ...
- * p0 p1 p2
- * (now) (~1ms ago) (~2ms ago)
- *
- * Let u_i denote the fraction of p_i that the entity was runnable.
- *
- * We then designate the fractions u_i as our co-efficients, yielding the
- * following representation of historical load:
- * u_0 + u_1*y + u_2*y^2 + u_3*y^3 + ...
- *
- * We choose y based on the with of a reasonably scheduling period, fixing:
- * y^32 = 0.5
- *
- * This means that the contribution to load ~32ms ago (u_32) will be weighted
- * approximately half as much as the contribution to load within the last ms
- * (u_0).
- *
- * When a period "rolls over" and we have new u_0`, multiplying the previous
- * sum again by y is sufficient to update:
- * load_avg = u_0` + y*(u_0 + u_1*y + u_2*y^2 + ... )
- * = u_0 + u_1*y + u_2*y^2 + ... [re-labeling u_i --> u_{i+1}]
- */
-static __always_inline int
-___update_load_sum(u64 now, int cpu, struct sched_avg *sa,
- unsigned long load, unsigned long runnable, int running)
-{
- u64 delta;
-
- delta = now - sa->last_update_time;
- /*
- * This should only happen when time goes backwards, which it
- * unfortunately does during sched clock init when we swap over to TSC.
- */
- if ((s64)delta < 0) {
- sa->last_update_time = now;
- return 0;
- }
-
- /*
- * Use 1024ns as the unit of measurement since it's a reasonable
- * approximation of 1us and fast to compute.
- */
- delta >>= 10;
- if (!delta)
- return 0;
-
- sa->last_update_time += delta << 10;
-
- /*
- * running is a subset of runnable (weight) so running can't be set if
- * runnable is clear. But there are some corner cases where the current
- * se has been already dequeued but cfs_rq->curr still points to it.
- * This means that weight will be 0 but not running for a sched_entity
- * but also for a cfs_rq if the latter becomes idle. As an example,
- * this happens during idle_balance() which calls
- * update_blocked_averages()
- */
- if (!load)
- runnable = running = 0;
-
- /*
- * Now we know we crossed measurement unit boundaries. The *_avg
- * accrues by two steps:
- *
- * Step 1: accumulate *_sum since last_update_time. If we haven't
- * crossed period boundaries, finish.
- */
- if (!accumulate_sum(delta, cpu, sa, load, runnable, running))
- return 0;
-
- return 1;
-}
-
-static __always_inline void
-___update_load_avg(struct sched_avg *sa, unsigned long load, unsigned long runnable)
-{
- u32 divider = LOAD_AVG_MAX - 1024 + sa->period_contrib;
-
- /*
- * Step 2: update *_avg.
- */
- sa->load_avg = div_u64(load * sa->load_sum, divider);
- sa->runnable_load_avg = div_u64(runnable * sa->runnable_load_sum, divider);
- sa->util_avg = sa->util_sum / divider;
-}
-
-/*
- * When a task is dequeued, its estimated utilization should not be update if
- * its util_avg has not been updated at least once.
- * This flag is used to synchronize util_avg updates with util_est updates.
- * We map this information into the LSB bit of the utilization saved at
- * dequeue time (i.e. util_est.dequeued).
- */
-#define UTIL_AVG_UNCHANGED 0x1
-
-static inline void cfs_se_util_change(struct sched_avg *avg)
-{
- unsigned int enqueued;
-
- if (!sched_feat(UTIL_EST))
- return;
-
- /* Avoid store if the flag has been already set */
- enqueued = avg->util_est.enqueued;
- if (!(enqueued & UTIL_AVG_UNCHANGED))
- return;
-
- /* Reset flag to report util_avg has been updated */
- enqueued &= ~UTIL_AVG_UNCHANGED;
- WRITE_ONCE(avg->util_est.enqueued, enqueued);
-}
-
-/*
- * sched_entity:
- *
- * task:
- * se_runnable() == se_weight()
- *
- * group: [ see update_cfs_group() ]
- * se_weight() = tg->weight * grq->load_avg / tg->load_avg
- * se_runnable() = se_weight(se) * grq->runnable_load_avg / grq->load_avg
- *
- * load_sum := runnable_sum
- * load_avg = se_weight(se) * runnable_avg
- *
- * runnable_load_sum := runnable_sum
- * runnable_load_avg = se_runnable(se) * runnable_avg
- *
- * XXX collapse load_sum and runnable_load_sum
- *
- * cfq_rs:
- *
- * load_sum = \Sum se_weight(se) * se->avg.load_sum
- * load_avg = \Sum se->avg.load_avg
- *
- * runnable_load_sum = \Sum se_runnable(se) * se->avg.runnable_load_sum
- * runnable_load_avg = \Sum se->avg.runable_load_avg
- */
-
-static int
-__update_load_avg_blocked_se(u64 now, int cpu, struct sched_entity *se)
-{
- if (entity_is_task(se))
- se->runnable_weight = se->load.weight;
-
- if (___update_load_sum(now, cpu, &se->avg, 0, 0, 0)) {
- ___update_load_avg(&se->avg, se_weight(se), se_runnable(se));
- return 1;
- }
-
- return 0;
-}
-
-static int
-__update_load_avg_se(u64 now, int cpu, struct cfs_rq *cfs_rq, struct sched_entity *se)
-{
- if (entity_is_task(se))
- se->runnable_weight = se->load.weight;
-
- if (___update_load_sum(now, cpu, &se->avg, !!se->on_rq, !!se->on_rq,
- cfs_rq->curr == se)) {
-
- ___update_load_avg(&se->avg, se_weight(se), se_runnable(se));
- cfs_se_util_change(&se->avg);
- return 1;
- }
-
- return 0;
-}
-
-static int
-__update_load_avg_cfs_rq(u64 now, int cpu, struct cfs_rq *cfs_rq)
-{
- if (___update_load_sum(now, cpu, &cfs_rq->avg,
- scale_load_down(cfs_rq->load.weight),
- scale_load_down(cfs_rq->runnable_weight),
- cfs_rq->curr != NULL)) {
-
- ___update_load_avg(&cfs_rq->avg, 1, 1);
- return 1;
- }
-
- return 0;
-}
-
#ifdef CONFIG_FAIR_GROUP_SCHED
/**
* update_tg_load_avg - update the tg's load avg
@@ -4039,12 +3714,6 @@ util_est_dequeue(struct cfs_rq *cfs_rq, struct task_struct *p, bool task_sleep)
#else /* CONFIG_SMP */
-static inline int
-update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq)
-{
- return 0;
-}
-
#define UPDATE_TG 0x0
#define SKIP_AGE_LOAD 0x0
#define DO_ATTACH 0x0
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