Merge in fixes before applying ongoing new work.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
CFLAGS_core.o := $(PROFILING) -fno-omit-frame-pointer
endif
-obj-y += core.o clock.o cputime.o idle_task.o fair.o rt.o stop_task.o
+obj-y += core.o proc.o clock.o cputime.o idle_task.o fair.o rt.o stop_task.o
obj-$(CONFIG_SMP) += cpupri.o
obj-$(CONFIG_SCHED_AUTOGROUP) += auto_group.o
obj-$(CONFIG_SCHEDSTATS) += stats.o
if (IS_ERR(tg))
goto out_free;
- sched_online_group(tg, &root_task_group);
-
kref_init(&ag->kref);
init_rwsem(&ag->lock);
ag->id = atomic_inc_return(&autogroup_seq_nr);
#endif
tg->autogroup = ag;
+ sched_online_group(tg, &root_task_group);
return ag;
out_free:
{
s64 period = sched_avg_period();
- while ((s64)(rq->clock - rq->age_stamp) > period) {
+ while ((s64)(rq_clock(rq) - rq->age_stamp) > period) {
/*
* Inline assembly required to prevent the compiler
* optimising this loop into a divmod call.
p->sched_class->task_woken(rq, p);
if (rq->idle_stamp) {
- u64 delta = rq->clock - rq->idle_stamp;
+ u64 delta = rq_clock(rq) - rq->idle_stamp;
u64 max = 2*sysctl_sched_migration_cost;
if (delta > max)
rq = __task_rq_lock(p);
if (p->on_rq) {
+ /* check_preempt_curr() may use rq clock */
+ update_rq_clock(rq);
ttwu_do_wakeup(rq, p, wake_flags);
ret = 1;
}
return atomic_read(&this->nr_iowait);
}
-unsigned long this_cpu_load(void)
-{
- struct rq *this = this_rq();
- return this->cpu_load[0];
-}
-
-
-/*
- * Global load-average calculations
- *
- * We take a distributed and async approach to calculating the global load-avg
- * in order to minimize overhead.
- *
- * The global load average is an exponentially decaying average of nr_running +
- * nr_uninterruptible.
- *
- * Once every LOAD_FREQ:
- *
- * nr_active = 0;
- * for_each_possible_cpu(cpu)
- * nr_active += cpu_of(cpu)->nr_running + cpu_of(cpu)->nr_uninterruptible;
- *
- * avenrun[n] = avenrun[0] * exp_n + nr_active * (1 - exp_n)
- *
- * Due to a number of reasons the above turns in the mess below:
- *
- * - for_each_possible_cpu() is prohibitively expensive on machines with
- * serious number of cpus, therefore we need to take a distributed approach
- * to calculating nr_active.
- *
- * \Sum_i x_i(t) = \Sum_i x_i(t) - x_i(t_0) | x_i(t_0) := 0
- * = \Sum_i { \Sum_j=1 x_i(t_j) - x_i(t_j-1) }
- *
- * So assuming nr_active := 0 when we start out -- true per definition, we
- * can simply take per-cpu deltas and fold those into a global accumulate
- * to obtain the same result. See calc_load_fold_active().
- *
- * Furthermore, in order to avoid synchronizing all per-cpu delta folding
- * across the machine, we assume 10 ticks is sufficient time for every
- * cpu to have completed this task.
- *
- * This places an upper-bound on the IRQ-off latency of the machine. Then
- * again, being late doesn't loose the delta, just wrecks the sample.
- *
- * - cpu_rq()->nr_uninterruptible isn't accurately tracked per-cpu because
- * this would add another cross-cpu cacheline miss and atomic operation
- * to the wakeup path. Instead we increment on whatever cpu the task ran
- * when it went into uninterruptible state and decrement on whatever cpu
- * did the wakeup. This means that only the sum of nr_uninterruptible over
- * all cpus yields the correct result.
- *
- * This covers the NO_HZ=n code, for extra head-aches, see the comment below.
- */
-
-/* Variables and functions for calc_load */
-static atomic_long_t calc_load_tasks;
-static unsigned long calc_load_update;
-unsigned long avenrun[3];
-EXPORT_SYMBOL(avenrun); /* should be removed */
-
-/**
- * get_avenrun - get the load average array
- * @loads: pointer to dest load array
- * @offset: offset to add
- * @shift: shift count to shift the result left
- *
- * These values are estimates at best, so no need for locking.
- */
-void get_avenrun(unsigned long *loads, unsigned long offset, int shift)
-{
- loads[0] = (avenrun[0] + offset) << shift;
- loads[1] = (avenrun[1] + offset) << shift;
- loads[2] = (avenrun[2] + offset) << shift;
-}
-
-static long calc_load_fold_active(struct rq *this_rq)
-{
- long nr_active, delta = 0;
-
- nr_active = this_rq->nr_running;
- nr_active += (long) this_rq->nr_uninterruptible;
-
- if (nr_active != this_rq->calc_load_active) {
- delta = nr_active - this_rq->calc_load_active;
- this_rq->calc_load_active = nr_active;
- }
-
- return delta;
-}
-
-/*
- * a1 = a0 * e + a * (1 - e)
- */
-static unsigned long
-calc_load(unsigned long load, unsigned long exp, unsigned long active)
-{
- load *= exp;
- load += active * (FIXED_1 - exp);
- load += 1UL << (FSHIFT - 1);
- return load >> FSHIFT;
-}
-
-#ifdef CONFIG_NO_HZ_COMMON
-/*
- * Handle NO_HZ for the global load-average.
- *
- * Since the above described distributed algorithm to compute the global
- * load-average relies on per-cpu sampling from the tick, it is affected by
- * NO_HZ.
- *
- * The basic idea is to fold the nr_active delta into a global idle-delta upon
- * entering NO_HZ state such that we can include this as an 'extra' cpu delta
- * when we read the global state.
- *
- * Obviously reality has to ruin such a delightfully simple scheme:
- *
- * - When we go NO_HZ idle during the window, we can negate our sample
- * contribution, causing under-accounting.
- *
- * We avoid this by keeping two idle-delta counters and flipping them
- * when the window starts, thus separating old and new NO_HZ load.
- *
- * The only trick is the slight shift in index flip for read vs write.
- *
- * 0s 5s 10s 15s
- * +10 +10 +10 +10
- * |-|-----------|-|-----------|-|-----------|-|
- * r:0 0 1 1 0 0 1 1 0
- * w:0 1 1 0 0 1 1 0 0
- *
- * This ensures we'll fold the old idle contribution in this window while
- * accumlating the new one.
- *
- * - When we wake up from NO_HZ idle during the window, we push up our
- * contribution, since we effectively move our sample point to a known
- * busy state.
- *
- * This is solved by pushing the window forward, and thus skipping the
- * sample, for this cpu (effectively using the idle-delta for this cpu which
- * was in effect at the time the window opened). This also solves the issue
- * of having to deal with a cpu having been in NOHZ idle for multiple
- * LOAD_FREQ intervals.
- *
- * When making the ILB scale, we should try to pull this in as well.
- */
-static atomic_long_t calc_load_idle[2];
-static int calc_load_idx;
-
-static inline int calc_load_write_idx(void)
-{
- int idx = calc_load_idx;
-
- /*
- * See calc_global_nohz(), if we observe the new index, we also
- * need to observe the new update time.
- */
- smp_rmb();
-
- /*
- * If the folding window started, make sure we start writing in the
- * next idle-delta.
- */
- if (!time_before(jiffies, calc_load_update))
- idx++;
-
- return idx & 1;
-}
-
-static inline int calc_load_read_idx(void)
-{
- return calc_load_idx & 1;
-}
-
-void calc_load_enter_idle(void)
-{
- struct rq *this_rq = this_rq();
- long delta;
-
- /*
- * We're going into NOHZ mode, if there's any pending delta, fold it
- * into the pending idle delta.
- */
- delta = calc_load_fold_active(this_rq);
- if (delta) {
- int idx = calc_load_write_idx();
- atomic_long_add(delta, &calc_load_idle[idx]);
- }
-}
-
-void calc_load_exit_idle(void)
-{
- struct rq *this_rq = this_rq();
-
- /*
- * If we're still before the sample window, we're done.
- */
- if (time_before(jiffies, this_rq->calc_load_update))
- return;
-
- /*
- * We woke inside or after the sample window, this means we're already
- * accounted through the nohz accounting, so skip the entire deal and
- * sync up for the next window.
- */
- this_rq->calc_load_update = calc_load_update;
- if (time_before(jiffies, this_rq->calc_load_update + 10))
- this_rq->calc_load_update += LOAD_FREQ;
-}
-
-static long calc_load_fold_idle(void)
-{
- int idx = calc_load_read_idx();
- long delta = 0;
-
- if (atomic_long_read(&calc_load_idle[idx]))
- delta = atomic_long_xchg(&calc_load_idle[idx], 0);
-
- return delta;
-}
-
-/**
- * fixed_power_int - compute: x^n, in O(log n) time
- *
- * @x: base of the power
- * @frac_bits: fractional bits of @x
- * @n: power to raise @x to.
- *
- * By exploiting the relation between the definition of the natural power
- * function: x^n := x*x*...*x (x multiplied by itself for n times), and
- * the binary encoding of numbers used by computers: n := \Sum n_i * 2^i,
- * (where: n_i \elem {0, 1}, the binary vector representing n),
- * we find: x^n := x^(\Sum n_i * 2^i) := \Prod x^(n_i * 2^i), which is
- * of course trivially computable in O(log_2 n), the length of our binary
- * vector.
- */
-static unsigned long
-fixed_power_int(unsigned long x, unsigned int frac_bits, unsigned int n)
-{
- unsigned long result = 1UL << frac_bits;
-
- if (n) for (;;) {
- if (n & 1) {
- result *= x;
- result += 1UL << (frac_bits - 1);
- result >>= frac_bits;
- }
- n >>= 1;
- if (!n)
- break;
- x *= x;
- x += 1UL << (frac_bits - 1);
- x >>= frac_bits;
- }
-
- return result;
-}
-
-/*
- * a1 = a0 * e + a * (1 - e)
- *
- * a2 = a1 * e + a * (1 - e)
- * = (a0 * e + a * (1 - e)) * e + a * (1 - e)
- * = a0 * e^2 + a * (1 - e) * (1 + e)
- *
- * a3 = a2 * e + a * (1 - e)
- * = (a0 * e^2 + a * (1 - e) * (1 + e)) * e + a * (1 - e)
- * = a0 * e^3 + a * (1 - e) * (1 + e + e^2)
- *
- * ...
- *
- * an = a0 * e^n + a * (1 - e) * (1 + e + ... + e^n-1) [1]
- * = a0 * e^n + a * (1 - e) * (1 - e^n)/(1 - e)
- * = a0 * e^n + a * (1 - e^n)
- *
- * [1] application of the geometric series:
- *
- * n 1 - x^(n+1)
- * S_n := \Sum x^i = -------------
- * i=0 1 - x
- */
-static unsigned long
-calc_load_n(unsigned long load, unsigned long exp,
- unsigned long active, unsigned int n)
-{
-
- return calc_load(load, fixed_power_int(exp, FSHIFT, n), active);
-}
-
-/*
- * NO_HZ can leave us missing all per-cpu ticks calling
- * calc_load_account_active(), but since an idle CPU folds its delta into
- * calc_load_tasks_idle per calc_load_account_idle(), all we need to do is fold
- * in the pending idle delta if our idle period crossed a load cycle boundary.
- *
- * Once we've updated the global active value, we need to apply the exponential
- * weights adjusted to the number of cycles missed.
- */
-static void calc_global_nohz(void)
-{
- long delta, active, n;
-
- if (!time_before(jiffies, calc_load_update + 10)) {
- /*
- * Catch-up, fold however many we are behind still
- */
- delta = jiffies - calc_load_update - 10;
- n = 1 + (delta / LOAD_FREQ);
-
- active = atomic_long_read(&calc_load_tasks);
- active = active > 0 ? active * FIXED_1 : 0;
-
- avenrun[0] = calc_load_n(avenrun[0], EXP_1, active, n);
- avenrun[1] = calc_load_n(avenrun[1], EXP_5, active, n);
- avenrun[2] = calc_load_n(avenrun[2], EXP_15, active, n);
-
- calc_load_update += n * LOAD_FREQ;
- }
-
- /*
- * Flip the idle index...
- *
- * Make sure we first write the new time then flip the index, so that
- * calc_load_write_idx() will see the new time when it reads the new
- * index, this avoids a double flip messing things up.
- */
- smp_wmb();
- calc_load_idx++;
-}
-#else /* !CONFIG_NO_HZ_COMMON */
-
-static inline long calc_load_fold_idle(void) { return 0; }
-static inline void calc_global_nohz(void) { }
-
-#endif /* CONFIG_NO_HZ_COMMON */
-
-/*
- * calc_load - update the avenrun load estimates 10 ticks after the
- * CPUs have updated calc_load_tasks.
- */
-void calc_global_load(unsigned long ticks)
-{
- long active, delta;
-
- if (time_before(jiffies, calc_load_update + 10))
- return;
-
- /*
- * Fold the 'old' idle-delta to include all NO_HZ cpus.
- */
- delta = calc_load_fold_idle();
- if (delta)
- atomic_long_add(delta, &calc_load_tasks);
-
- active = atomic_long_read(&calc_load_tasks);
- active = active > 0 ? active * FIXED_1 : 0;
-
- avenrun[0] = calc_load(avenrun[0], EXP_1, active);
- avenrun[1] = calc_load(avenrun[1], EXP_5, active);
- avenrun[2] = calc_load(avenrun[2], EXP_15, active);
-
- calc_load_update += LOAD_FREQ;
-
- /*
- * In case we idled for multiple LOAD_FREQ intervals, catch up in bulk.
- */
- calc_global_nohz();
-}
-
-/*
- * Called from update_cpu_load() to periodically update this CPU's
- * active count.
- */
-static void calc_load_account_active(struct rq *this_rq)
-{
- long delta;
-
- if (time_before(jiffies, this_rq->calc_load_update))
- return;
-
- delta = calc_load_fold_active(this_rq);
- if (delta)
- atomic_long_add(delta, &calc_load_tasks);
-
- this_rq->calc_load_update += LOAD_FREQ;
-}
-
-/*
- * End of global load-average stuff
- */
-
-/*
- * The exact cpuload at various idx values, calculated at every tick would be
- * load = (2^idx - 1) / 2^idx * load + 1 / 2^idx * cur_load
- *
- * If a cpu misses updates for n-1 ticks (as it was idle) and update gets called
- * on nth tick when cpu may be busy, then we have:
- * load = ((2^idx - 1) / 2^idx)^(n-1) * load
- * load = (2^idx - 1) / 2^idx) * load + 1 / 2^idx * cur_load
- *
- * decay_load_missed() below does efficient calculation of
- * load = ((2^idx - 1) / 2^idx)^(n-1) * load
- * avoiding 0..n-1 loop doing load = ((2^idx - 1) / 2^idx) * load
- *
- * The calculation is approximated on a 128 point scale.
- * degrade_zero_ticks is the number of ticks after which load at any
- * particular idx is approximated to be zero.
- * degrade_factor is a precomputed table, a row for each load idx.
- * Each column corresponds to degradation factor for a power of two ticks,
- * based on 128 point scale.
- * Example:
- * row 2, col 3 (=12) says that the degradation at load idx 2 after
- * 8 ticks is 12/128 (which is an approximation of exact factor 3^8/4^8).
- *
- * With this power of 2 load factors, we can degrade the load n times
- * by looking at 1 bits in n and doing as many mult/shift instead of
- * n mult/shifts needed by the exact degradation.
- */
-#define DEGRADE_SHIFT 7
-static const unsigned char
- degrade_zero_ticks[CPU_LOAD_IDX_MAX] = {0, 8, 32, 64, 128};
-static const unsigned char
- degrade_factor[CPU_LOAD_IDX_MAX][DEGRADE_SHIFT + 1] = {
- {0, 0, 0, 0, 0, 0, 0, 0},
- {64, 32, 8, 0, 0, 0, 0, 0},
- {96, 72, 40, 12, 1, 0, 0},
- {112, 98, 75, 43, 15, 1, 0},
- {120, 112, 98, 76, 45, 16, 2} };
-
-/*
- * Update cpu_load for any missed ticks, due to tickless idle. The backlog
- * would be when CPU is idle and so we just decay the old load without
- * adding any new load.
- */
-static unsigned long
-decay_load_missed(unsigned long load, unsigned long missed_updates, int idx)
-{
- int j = 0;
-
- if (!missed_updates)
- return load;
-
- if (missed_updates >= degrade_zero_ticks[idx])
- return 0;
-
- if (idx == 1)
- return load >> missed_updates;
-
- while (missed_updates) {
- if (missed_updates % 2)
- load = (load * degrade_factor[idx][j]) >> DEGRADE_SHIFT;
-
- missed_updates >>= 1;
- j++;
- }
- return load;
-}
-
-/*
- * Update rq->cpu_load[] statistics. This function is usually called every
- * scheduler tick (TICK_NSEC). With tickless idle this will not be called
- * every tick. We fix it up based on jiffies.
- */
-static void __update_cpu_load(struct rq *this_rq, unsigned long this_load,
- unsigned long pending_updates)
-{
- int i, scale;
-
- this_rq->nr_load_updates++;
-
- /* Update our load: */
- this_rq->cpu_load[0] = this_load; /* Fasttrack for idx 0 */
- for (i = 1, scale = 2; i < CPU_LOAD_IDX_MAX; i++, scale += scale) {
- unsigned long old_load, new_load;
-
- /* scale is effectively 1 << i now, and >> i divides by scale */
-
- old_load = this_rq->cpu_load[i];
- old_load = decay_load_missed(old_load, pending_updates - 1, i);
- new_load = this_load;
- /*
- * Round up the averaging division if load is increasing. This
- * prevents us from getting stuck on 9 if the load is 10, for
- * example.
- */
- if (new_load > old_load)
- new_load += scale - 1;
-
- this_rq->cpu_load[i] = (old_load * (scale - 1) + new_load) >> i;
- }
-
- sched_avg_update(this_rq);
-}
-
-#ifdef CONFIG_NO_HZ_COMMON
-/*
- * There is no sane way to deal with nohz on smp when using jiffies because the
- * cpu doing the jiffies update might drift wrt the cpu doing the jiffy reading
- * causing off-by-one errors in observed deltas; {0,2} instead of {1,1}.
- *
- * Therefore we cannot use the delta approach from the regular tick since that
- * would seriously skew the load calculation. However we'll make do for those
- * updates happening while idle (nohz_idle_balance) or coming out of idle
- * (tick_nohz_idle_exit).
- *
- * This means we might still be one tick off for nohz periods.
- */
-
-/*
- * Called from nohz_idle_balance() to update the load ratings before doing the
- * idle balance.
- */
-void update_idle_cpu_load(struct rq *this_rq)
-{
- unsigned long curr_jiffies = ACCESS_ONCE(jiffies);
- unsigned long load = this_rq->load.weight;
- unsigned long pending_updates;
-
- /*
- * bail if there's load or we're actually up-to-date.
- */
- if (load || curr_jiffies == this_rq->last_load_update_tick)
- return;
-
- pending_updates = curr_jiffies - this_rq->last_load_update_tick;
- this_rq->last_load_update_tick = curr_jiffies;
-
- __update_cpu_load(this_rq, load, pending_updates);
-}
-
-/*
- * Called from tick_nohz_idle_exit() -- try and fix up the ticks we missed.
- */
-void update_cpu_load_nohz(void)
-{
- struct rq *this_rq = this_rq();
- unsigned long curr_jiffies = ACCESS_ONCE(jiffies);
- unsigned long pending_updates;
-
- if (curr_jiffies == this_rq->last_load_update_tick)
- return;
-
- raw_spin_lock(&this_rq->lock);
- pending_updates = curr_jiffies - this_rq->last_load_update_tick;
- if (pending_updates) {
- this_rq->last_load_update_tick = curr_jiffies;
- /*
- * We were idle, this means load 0, the current load might be
- * !0 due to remote wakeups and the sort.
- */
- __update_cpu_load(this_rq, 0, pending_updates);
- }
- raw_spin_unlock(&this_rq->lock);
-}
-#endif /* CONFIG_NO_HZ_COMMON */
-
-/*
- * Called from scheduler_tick()
- */
-static void update_cpu_load_active(struct rq *this_rq)
-{
- /*
- * See the mess around update_idle_cpu_load() / update_cpu_load_nohz().
- */
- this_rq->last_load_update_tick = jiffies;
- __update_cpu_load(this_rq, this_rq->load.weight, 1);
-
- calc_load_account_active(this_rq);
-}
-
#ifdef CONFIG_SMP
/*
if (task_current(rq, p)) {
update_rq_clock(rq);
- ns = rq->clock_task - p->se.exec_start;
+ ns = rq_clock_task(rq) - p->se.exec_start;
if ((s64)ns < 0)
ns = 0;
}
*/
rq->stop = NULL;
+ /*
+ * put_prev_task() and pick_next_task() sched
+ * class method both need to have an up-to-date
+ * value of rq->clock[_task]
+ */
+ update_rq_clock(rq);
+
for ( ; ; ) {
/*
* There's this thread running, bail when that's the only
hotcpu_notifier(cpuset_cpu_active, CPU_PRI_CPUSET_ACTIVE);
hotcpu_notifier(cpuset_cpu_inactive, CPU_PRI_CPUSET_INACTIVE);
- /* RT runtime code needs to handle some hotplug events */
- hotcpu_notifier(update_runtime, 0);
-
init_hrtick();
/* Move init over to a non-isolated CPU */
for (;;) {
/* Make sure "rtime" is the bigger of stime/rtime */
- if (stime > rtime) {
- u64 tmp = rtime; rtime = stime; stime = tmp;
- }
+ if (stime > rtime)
+ swap(rtime, stime);
/* Make sure 'total' fits in 32 bits */
if (total >> 32)
unsigned int sysctl_sched_cfs_bandwidth_slice = 5000UL;
#endif
+static inline void update_load_add(struct load_weight *lw, unsigned long inc)
+{
+ lw->weight += inc;
+ lw->inv_weight = 0;
+}
+
+static inline void update_load_sub(struct load_weight *lw, unsigned long dec)
+{
+ lw->weight -= dec;
+ lw->inv_weight = 0;
+}
+
+static inline void update_load_set(struct load_weight *lw, unsigned long w)
+{
+ lw->weight = w;
+ lw->inv_weight = 0;
+}
+
/*
* Increase the granularity value when there are more CPUs,
* because with more CPUs the 'effective latency' as visible
static void update_curr(struct cfs_rq *cfs_rq)
{
struct sched_entity *curr = cfs_rq->curr;
- u64 now = rq_of(cfs_rq)->clock_task;
+ u64 now = rq_clock_task(rq_of(cfs_rq));
unsigned long delta_exec;
if (unlikely(!curr))
static inline void
update_stats_wait_start(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
- schedstat_set(se->statistics.wait_start, rq_of(cfs_rq)->clock);
+ schedstat_set(se->statistics.wait_start, rq_clock(rq_of(cfs_rq)));
}
/*
update_stats_wait_end(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
schedstat_set(se->statistics.wait_max, max(se->statistics.wait_max,
- rq_of(cfs_rq)->clock - se->statistics.wait_start));
+ rq_clock(rq_of(cfs_rq)) - se->statistics.wait_start));
schedstat_set(se->statistics.wait_count, se->statistics.wait_count + 1);
schedstat_set(se->statistics.wait_sum, se->statistics.wait_sum +
- rq_of(cfs_rq)->clock - se->statistics.wait_start);
+ rq_clock(rq_of(cfs_rq)) - se->statistics.wait_start);
#ifdef CONFIG_SCHEDSTATS
if (entity_is_task(se)) {
trace_sched_stat_wait(task_of(se),
- rq_of(cfs_rq)->clock - se->statistics.wait_start);
+ rq_clock(rq_of(cfs_rq)) - se->statistics.wait_start);
}
#endif
schedstat_set(se->statistics.wait_start, 0);
/*
* We are starting a new run period:
*/
- se->exec_start = rq_of(cfs_rq)->clock_task;
+ se->exec_start = rq_clock_task(rq_of(cfs_rq));
}
/**************************************************
static inline void update_rq_runnable_avg(struct rq *rq, int runnable)
{
- __update_entity_runnable_avg(rq->clock_task, &rq->avg, runnable);
+ __update_entity_runnable_avg(rq_clock_task(rq), &rq->avg, runnable);
__update_tg_runnable_avg(&rq->avg, &rq->cfs);
}
* accumulated while sleeping.
*/
if (unlikely(se->avg.decay_count <= 0)) {
- se->avg.last_runnable_update = rq_of(cfs_rq)->clock_task;
+ se->avg.last_runnable_update = rq_clock_task(rq_of(cfs_rq));
if (se->avg.decay_count) {
/*
* In a wake-up migration we have to approximate the
tsk = task_of(se);
if (se->statistics.sleep_start) {
- u64 delta = rq_of(cfs_rq)->clock - se->statistics.sleep_start;
+ u64 delta = rq_clock(rq_of(cfs_rq)) - se->statistics.sleep_start;
if ((s64)delta < 0)
delta = 0;
}
}
if (se->statistics.block_start) {
- u64 delta = rq_of(cfs_rq)->clock - se->statistics.block_start;
+ u64 delta = rq_clock(rq_of(cfs_rq)) - se->statistics.block_start;
if ((s64)delta < 0)
delta = 0;
struct task_struct *tsk = task_of(se);
if (tsk->state & TASK_INTERRUPTIBLE)
- se->statistics.sleep_start = rq_of(cfs_rq)->clock;
+ se->statistics.sleep_start = rq_clock(rq_of(cfs_rq));
if (tsk->state & TASK_UNINTERRUPTIBLE)
- se->statistics.block_start = rq_of(cfs_rq)->clock;
+ se->statistics.block_start = rq_clock(rq_of(cfs_rq));
}
#endif
}
if (unlikely(cfs_rq->throttle_count))
return cfs_rq->throttled_clock_task;
- return rq_of(cfs_rq)->clock_task - cfs_rq->throttled_clock_task_time;
+ return rq_clock_task(rq_of(cfs_rq)) - cfs_rq->throttled_clock_task_time;
}
/* returns 0 on failure to allocate runtime */
static void expire_cfs_rq_runtime(struct cfs_rq *cfs_rq)
{
struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg);
- struct rq *rq = rq_of(cfs_rq);
/* if the deadline is ahead of our clock, nothing to do */
- if (likely((s64)(rq->clock - cfs_rq->runtime_expires) < 0))
+ if (likely((s64)(rq_clock(rq_of(cfs_rq)) - cfs_rq->runtime_expires) < 0))
return;
if (cfs_rq->runtime_remaining < 0)
#ifdef CONFIG_SMP
if (!cfs_rq->throttle_count) {
/* adjust cfs_rq_clock_task() */
- cfs_rq->throttled_clock_task_time += rq->clock_task -
+ cfs_rq->throttled_clock_task_time += rq_clock_task(rq) -
cfs_rq->throttled_clock_task;
}
#endif
/* group is entering throttled state, stop time */
if (!cfs_rq->throttle_count)
- cfs_rq->throttled_clock_task = rq->clock_task;
+ cfs_rq->throttled_clock_task = rq_clock_task(rq);
cfs_rq->throttle_count++;
return 0;
rq->nr_running -= task_delta;
cfs_rq->throttled = 1;
- cfs_rq->throttled_clock = rq->clock;
+ cfs_rq->throttled_clock = rq_clock(rq);
raw_spin_lock(&cfs_b->lock);
list_add_tail_rcu(&cfs_rq->throttled_list, &cfs_b->throttled_cfs_rq);
raw_spin_unlock(&cfs_b->lock);
se = cfs_rq->tg->se[cpu_of(rq_of(cfs_rq))];
cfs_rq->throttled = 0;
+
+ update_rq_clock(rq);
+
raw_spin_lock(&cfs_b->lock);
- cfs_b->throttled_time += rq->clock - cfs_rq->throttled_clock;
+ cfs_b->throttled_time += rq_clock(rq) - cfs_rq->throttled_clock;
list_del_rcu(&cfs_rq->throttled_list);
raw_spin_unlock(&cfs_b->lock);
- update_rq_clock(rq);
/* update hierarchical throttle state */
walk_tg_tree_from(cfs_rq->tg, tg_nop, tg_unthrottle_up, (void *)rq);
#else /* CONFIG_CFS_BANDWIDTH */
static inline u64 cfs_rq_clock_task(struct cfs_rq *cfs_rq)
{
- return rq_of(cfs_rq)->clock_task;
+ return rq_clock_task(rq_of(cfs_rq));
}
static void account_cfs_rq_runtime(struct cfs_rq *cfs_rq,
* 2) too many balance attempts have failed.
*/
- tsk_cache_hot = task_hot(p, env->src_rq->clock_task, env->sd);
+ tsk_cache_hot = task_hot(p, rq_clock_task(env->src_rq), env->sd);
if (!tsk_cache_hot ||
env->sd->nr_balance_failed > env->sd->cache_nice_tries) {
age_stamp = ACCESS_ONCE(rq->age_stamp);
avg = ACCESS_ONCE(rq->rt_avg);
- total = sched_avg_period() + (rq->clock - age_stamp);
+ total = sched_avg_period() + (rq_clock(rq) - age_stamp);
if (unlikely(total < avg)) {
/* Ensures that power won't end up being negative */
int pulled_task = 0;
unsigned long next_balance = jiffies + HZ;
- this_rq->idle_stamp = this_rq->clock;
+ this_rq->idle_stamp = rq_clock(this_rq);
if (this_rq->avg_idle < sysctl_sched_migration_cost)
return;
static inline void set_cpu_sd_state_busy(void)
{
struct sched_domain *sd;
- int cpu = smp_processor_id();
rcu_read_lock();
- sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd);
+ sd = rcu_dereference_check_sched_domain(this_rq()->sd);
if (!sd || !sd->nohz_idle)
goto unlock;
void set_cpu_sd_state_idle(void)
{
struct sched_domain *sd;
- int cpu = smp_processor_id();
rcu_read_lock();
- sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd);
+ sd = rcu_dereference_check_sched_domain(this_rq()->sd);
if (!sd || sd->nohz_idle)
goto unlock;
se = tg->se[i];
/* Propagate contribution to hierarchy */
raw_spin_lock_irqsave(&rq->lock, flags);
+
+ /* Possible calls to update_curr() need rq clock */
+ update_rq_clock(rq);
for_each_sched_entity(se)
update_cfs_shares(group_cfs_rq(se));
raw_spin_unlock_irqrestore(&rq->lock, flags);
--- /dev/null
+/*
+ * kernel/sched/proc.c
+ *
+ * Kernel load calculations, forked from sched/core.c
+ */
+
+#include <linux/export.h>
+
+#include "sched.h"
+
+unsigned long this_cpu_load(void)
+{
+ struct rq *this = this_rq();
+ return this->cpu_load[0];
+}
+
+
+/*
+ * Global load-average calculations
+ *
+ * We take a distributed and async approach to calculating the global load-avg
+ * in order to minimize overhead.
+ *
+ * The global load average is an exponentially decaying average of nr_running +
+ * nr_uninterruptible.
+ *
+ * Once every LOAD_FREQ:
+ *
+ * nr_active = 0;
+ * for_each_possible_cpu(cpu)
+ * nr_active += cpu_of(cpu)->nr_running + cpu_of(cpu)->nr_uninterruptible;
+ *
+ * avenrun[n] = avenrun[0] * exp_n + nr_active * (1 - exp_n)
+ *
+ * Due to a number of reasons the above turns in the mess below:
+ *
+ * - for_each_possible_cpu() is prohibitively expensive on machines with
+ * serious number of cpus, therefore we need to take a distributed approach
+ * to calculating nr_active.
+ *
+ * \Sum_i x_i(t) = \Sum_i x_i(t) - x_i(t_0) | x_i(t_0) := 0
+ * = \Sum_i { \Sum_j=1 x_i(t_j) - x_i(t_j-1) }
+ *
+ * So assuming nr_active := 0 when we start out -- true per definition, we
+ * can simply take per-cpu deltas and fold those into a global accumulate
+ * to obtain the same result. See calc_load_fold_active().
+ *
+ * Furthermore, in order to avoid synchronizing all per-cpu delta folding
+ * across the machine, we assume 10 ticks is sufficient time for every
+ * cpu to have completed this task.
+ *
+ * This places an upper-bound on the IRQ-off latency of the machine. Then
+ * again, being late doesn't loose the delta, just wrecks the sample.
+ *
+ * - cpu_rq()->nr_uninterruptible isn't accurately tracked per-cpu because
+ * this would add another cross-cpu cacheline miss and atomic operation
+ * to the wakeup path. Instead we increment on whatever cpu the task ran
+ * when it went into uninterruptible state and decrement on whatever cpu
+ * did the wakeup. This means that only the sum of nr_uninterruptible over
+ * all cpus yields the correct result.
+ *
+ * This covers the NO_HZ=n code, for extra head-aches, see the comment below.
+ */
+
+/* Variables and functions for calc_load */
+atomic_long_t calc_load_tasks;
+unsigned long calc_load_update;
+unsigned long avenrun[3];
+EXPORT_SYMBOL(avenrun); /* should be removed */
+
+/**
+ * get_avenrun - get the load average array
+ * @loads: pointer to dest load array
+ * @offset: offset to add
+ * @shift: shift count to shift the result left
+ *
+ * These values are estimates at best, so no need for locking.
+ */
+void get_avenrun(unsigned long *loads, unsigned long offset, int shift)
+{
+ loads[0] = (avenrun[0] + offset) << shift;
+ loads[1] = (avenrun[1] + offset) << shift;
+ loads[2] = (avenrun[2] + offset) << shift;
+}
+
+long calc_load_fold_active(struct rq *this_rq)
+{
+ long nr_active, delta = 0;
+
+ nr_active = this_rq->nr_running;
+ nr_active += (long) this_rq->nr_uninterruptible;
+
+ if (nr_active != this_rq->calc_load_active) {
+ delta = nr_active - this_rq->calc_load_active;
+ this_rq->calc_load_active = nr_active;
+ }
+
+ return delta;
+}
+
+/*
+ * a1 = a0 * e + a * (1 - e)
+ */
+static unsigned long
+calc_load(unsigned long load, unsigned long exp, unsigned long active)
+{
+ load *= exp;
+ load += active * (FIXED_1 - exp);
+ load += 1UL << (FSHIFT - 1);
+ return load >> FSHIFT;
+}
+
+#ifdef CONFIG_NO_HZ_COMMON
+/*
+ * Handle NO_HZ for the global load-average.
+ *
+ * Since the above described distributed algorithm to compute the global
+ * load-average relies on per-cpu sampling from the tick, it is affected by
+ * NO_HZ.
+ *
+ * The basic idea is to fold the nr_active delta into a global idle-delta upon
+ * entering NO_HZ state such that we can include this as an 'extra' cpu delta
+ * when we read the global state.
+ *
+ * Obviously reality has to ruin such a delightfully simple scheme:
+ *
+ * - When we go NO_HZ idle during the window, we can negate our sample
+ * contribution, causing under-accounting.
+ *
+ * We avoid this by keeping two idle-delta counters and flipping them
+ * when the window starts, thus separating old and new NO_HZ load.
+ *
+ * The only trick is the slight shift in index flip for read vs write.
+ *
+ * 0s 5s 10s 15s
+ * +10 +10 +10 +10
+ * |-|-----------|-|-----------|-|-----------|-|
+ * r:0 0 1 1 0 0 1 1 0
+ * w:0 1 1 0 0 1 1 0 0
+ *
+ * This ensures we'll fold the old idle contribution in this window while
+ * accumlating the new one.
+ *
+ * - When we wake up from NO_HZ idle during the window, we push up our
+ * contribution, since we effectively move our sample point to a known
+ * busy state.
+ *
+ * This is solved by pushing the window forward, and thus skipping the
+ * sample, for this cpu (effectively using the idle-delta for this cpu which
+ * was in effect at the time the window opened). This also solves the issue
+ * of having to deal with a cpu having been in NOHZ idle for multiple
+ * LOAD_FREQ intervals.
+ *
+ * When making the ILB scale, we should try to pull this in as well.
+ */
+static atomic_long_t calc_load_idle[2];
+static int calc_load_idx;
+
+static inline int calc_load_write_idx(void)
+{
+ int idx = calc_load_idx;
+
+ /*
+ * See calc_global_nohz(), if we observe the new index, we also
+ * need to observe the new update time.
+ */
+ smp_rmb();
+
+ /*
+ * If the folding window started, make sure we start writing in the
+ * next idle-delta.
+ */
+ if (!time_before(jiffies, calc_load_update))
+ idx++;
+
+ return idx & 1;
+}
+
+static inline int calc_load_read_idx(void)
+{
+ return calc_load_idx & 1;
+}
+
+void calc_load_enter_idle(void)
+{
+ struct rq *this_rq = this_rq();
+ long delta;
+
+ /*
+ * We're going into NOHZ mode, if there's any pending delta, fold it
+ * into the pending idle delta.
+ */
+ delta = calc_load_fold_active(this_rq);
+ if (delta) {
+ int idx = calc_load_write_idx();
+ atomic_long_add(delta, &calc_load_idle[idx]);
+ }
+}
+
+void calc_load_exit_idle(void)
+{
+ struct rq *this_rq = this_rq();
+
+ /*
+ * If we're still before the sample window, we're done.
+ */
+ if (time_before(jiffies, this_rq->calc_load_update))
+ return;
+
+ /*
+ * We woke inside or after the sample window, this means we're already
+ * accounted through the nohz accounting, so skip the entire deal and
+ * sync up for the next window.
+ */
+ this_rq->calc_load_update = calc_load_update;
+ if (time_before(jiffies, this_rq->calc_load_update + 10))
+ this_rq->calc_load_update += LOAD_FREQ;
+}
+
+static long calc_load_fold_idle(void)
+{
+ int idx = calc_load_read_idx();
+ long delta = 0;
+
+ if (atomic_long_read(&calc_load_idle[idx]))
+ delta = atomic_long_xchg(&calc_load_idle[idx], 0);
+
+ return delta;
+}
+
+/**
+ * fixed_power_int - compute: x^n, in O(log n) time
+ *
+ * @x: base of the power
+ * @frac_bits: fractional bits of @x
+ * @n: power to raise @x to.
+ *
+ * By exploiting the relation between the definition of the natural power
+ * function: x^n := x*x*...*x (x multiplied by itself for n times), and
+ * the binary encoding of numbers used by computers: n := \Sum n_i * 2^i,
+ * (where: n_i \elem {0, 1}, the binary vector representing n),
+ * we find: x^n := x^(\Sum n_i * 2^i) := \Prod x^(n_i * 2^i), which is
+ * of course trivially computable in O(log_2 n), the length of our binary
+ * vector.
+ */
+static unsigned long
+fixed_power_int(unsigned long x, unsigned int frac_bits, unsigned int n)
+{
+ unsigned long result = 1UL << frac_bits;
+
+ if (n) for (;;) {
+ if (n & 1) {
+ result *= x;
+ result += 1UL << (frac_bits - 1);
+ result >>= frac_bits;
+ }
+ n >>= 1;
+ if (!n)
+ break;
+ x *= x;
+ x += 1UL << (frac_bits - 1);
+ x >>= frac_bits;
+ }
+
+ return result;
+}
+
+/*
+ * a1 = a0 * e + a * (1 - e)
+ *
+ * a2 = a1 * e + a * (1 - e)
+ * = (a0 * e + a * (1 - e)) * e + a * (1 - e)
+ * = a0 * e^2 + a * (1 - e) * (1 + e)
+ *
+ * a3 = a2 * e + a * (1 - e)
+ * = (a0 * e^2 + a * (1 - e) * (1 + e)) * e + a * (1 - e)
+ * = a0 * e^3 + a * (1 - e) * (1 + e + e^2)
+ *
+ * ...
+ *
+ * an = a0 * e^n + a * (1 - e) * (1 + e + ... + e^n-1) [1]
+ * = a0 * e^n + a * (1 - e) * (1 - e^n)/(1 - e)
+ * = a0 * e^n + a * (1 - e^n)
+ *
+ * [1] application of the geometric series:
+ *
+ * n 1 - x^(n+1)
+ * S_n := \Sum x^i = -------------
+ * i=0 1 - x
+ */
+static unsigned long
+calc_load_n(unsigned long load, unsigned long exp,
+ unsigned long active, unsigned int n)
+{
+
+ return calc_load(load, fixed_power_int(exp, FSHIFT, n), active);
+}
+
+/*
+ * NO_HZ can leave us missing all per-cpu ticks calling
+ * calc_load_account_active(), but since an idle CPU folds its delta into
+ * calc_load_tasks_idle per calc_load_account_idle(), all we need to do is fold
+ * in the pending idle delta if our idle period crossed a load cycle boundary.
+ *
+ * Once we've updated the global active value, we need to apply the exponential
+ * weights adjusted to the number of cycles missed.
+ */
+static void calc_global_nohz(void)
+{
+ long delta, active, n;
+
+ if (!time_before(jiffies, calc_load_update + 10)) {
+ /*
+ * Catch-up, fold however many we are behind still
+ */
+ delta = jiffies - calc_load_update - 10;
+ n = 1 + (delta / LOAD_FREQ);
+
+ active = atomic_long_read(&calc_load_tasks);
+ active = active > 0 ? active * FIXED_1 : 0;
+
+ avenrun[0] = calc_load_n(avenrun[0], EXP_1, active, n);
+ avenrun[1] = calc_load_n(avenrun[1], EXP_5, active, n);
+ avenrun[2] = calc_load_n(avenrun[2], EXP_15, active, n);
+
+ calc_load_update += n * LOAD_FREQ;
+ }
+
+ /*
+ * Flip the idle index...
+ *
+ * Make sure we first write the new time then flip the index, so that
+ * calc_load_write_idx() will see the new time when it reads the new
+ * index, this avoids a double flip messing things up.
+ */
+ smp_wmb();
+ calc_load_idx++;
+}
+#else /* !CONFIG_NO_HZ_COMMON */
+
+static inline long calc_load_fold_idle(void) { return 0; }
+static inline void calc_global_nohz(void) { }
+
+#endif /* CONFIG_NO_HZ_COMMON */
+
+/*
+ * calc_load - update the avenrun load estimates 10 ticks after the
+ * CPUs have updated calc_load_tasks.
+ */
+void calc_global_load(unsigned long ticks)
+{
+ long active, delta;
+
+ if (time_before(jiffies, calc_load_update + 10))
+ return;
+
+ /*
+ * Fold the 'old' idle-delta to include all NO_HZ cpus.
+ */
+ delta = calc_load_fold_idle();
+ if (delta)
+ atomic_long_add(delta, &calc_load_tasks);
+
+ active = atomic_long_read(&calc_load_tasks);
+ active = active > 0 ? active * FIXED_1 : 0;
+
+ avenrun[0] = calc_load(avenrun[0], EXP_1, active);
+ avenrun[1] = calc_load(avenrun[1], EXP_5, active);
+ avenrun[2] = calc_load(avenrun[2], EXP_15, active);
+
+ calc_load_update += LOAD_FREQ;
+
+ /*
+ * In case we idled for multiple LOAD_FREQ intervals, catch up in bulk.
+ */
+ calc_global_nohz();
+}
+
+/*
+ * Called from update_cpu_load() to periodically update this CPU's
+ * active count.
+ */
+static void calc_load_account_active(struct rq *this_rq)
+{
+ long delta;
+
+ if (time_before(jiffies, this_rq->calc_load_update))
+ return;
+
+ delta = calc_load_fold_active(this_rq);
+ if (delta)
+ atomic_long_add(delta, &calc_load_tasks);
+
+ this_rq->calc_load_update += LOAD_FREQ;
+}
+
+/*
+ * End of global load-average stuff
+ */
+
+/*
+ * The exact cpuload at various idx values, calculated at every tick would be
+ * load = (2^idx - 1) / 2^idx * load + 1 / 2^idx * cur_load
+ *
+ * If a cpu misses updates for n-1 ticks (as it was idle) and update gets called
+ * on nth tick when cpu may be busy, then we have:
+ * load = ((2^idx - 1) / 2^idx)^(n-1) * load
+ * load = (2^idx - 1) / 2^idx) * load + 1 / 2^idx * cur_load
+ *
+ * decay_load_missed() below does efficient calculation of
+ * load = ((2^idx - 1) / 2^idx)^(n-1) * load
+ * avoiding 0..n-1 loop doing load = ((2^idx - 1) / 2^idx) * load
+ *
+ * The calculation is approximated on a 128 point scale.
+ * degrade_zero_ticks is the number of ticks after which load at any
+ * particular idx is approximated to be zero.
+ * degrade_factor is a precomputed table, a row for each load idx.
+ * Each column corresponds to degradation factor for a power of two ticks,
+ * based on 128 point scale.
+ * Example:
+ * row 2, col 3 (=12) says that the degradation at load idx 2 after
+ * 8 ticks is 12/128 (which is an approximation of exact factor 3^8/4^8).
+ *
+ * With this power of 2 load factors, we can degrade the load n times
+ * by looking at 1 bits in n and doing as many mult/shift instead of
+ * n mult/shifts needed by the exact degradation.
+ */
+#define DEGRADE_SHIFT 7
+static const unsigned char
+ degrade_zero_ticks[CPU_LOAD_IDX_MAX] = {0, 8, 32, 64, 128};
+static const unsigned char
+ degrade_factor[CPU_LOAD_IDX_MAX][DEGRADE_SHIFT + 1] = {
+ {0, 0, 0, 0, 0, 0, 0, 0},
+ {64, 32, 8, 0, 0, 0, 0, 0},
+ {96, 72, 40, 12, 1, 0, 0},
+ {112, 98, 75, 43, 15, 1, 0},
+ {120, 112, 98, 76, 45, 16, 2} };
+
+/*
+ * Update cpu_load for any missed ticks, due to tickless idle. The backlog
+ * would be when CPU is idle and so we just decay the old load without
+ * adding any new load.
+ */
+static unsigned long
+decay_load_missed(unsigned long load, unsigned long missed_updates, int idx)
+{
+ int j = 0;
+
+ if (!missed_updates)
+ return load;
+
+ if (missed_updates >= degrade_zero_ticks[idx])
+ return 0;
+
+ if (idx == 1)
+ return load >> missed_updates;
+
+ while (missed_updates) {
+ if (missed_updates % 2)
+ load = (load * degrade_factor[idx][j]) >> DEGRADE_SHIFT;
+
+ missed_updates >>= 1;
+ j++;
+ }
+ return load;
+}
+
+/*
+ * Update rq->cpu_load[] statistics. This function is usually called every
+ * scheduler tick (TICK_NSEC). With tickless idle this will not be called
+ * every tick. We fix it up based on jiffies.
+ */
+static void __update_cpu_load(struct rq *this_rq, unsigned long this_load,
+ unsigned long pending_updates)
+{
+ int i, scale;
+
+ this_rq->nr_load_updates++;
+
+ /* Update our load: */
+ this_rq->cpu_load[0] = this_load; /* Fasttrack for idx 0 */
+ for (i = 1, scale = 2; i < CPU_LOAD_IDX_MAX; i++, scale += scale) {
+ unsigned long old_load, new_load;
+
+ /* scale is effectively 1 << i now, and >> i divides by scale */
+
+ old_load = this_rq->cpu_load[i];
+ old_load = decay_load_missed(old_load, pending_updates - 1, i);
+ new_load = this_load;
+ /*
+ * Round up the averaging division if load is increasing. This
+ * prevents us from getting stuck on 9 if the load is 10, for
+ * example.
+ */
+ if (new_load > old_load)
+ new_load += scale - 1;
+
+ this_rq->cpu_load[i] = (old_load * (scale - 1) + new_load) >> i;
+ }
+
+ sched_avg_update(this_rq);
+}
+
+#ifdef CONFIG_NO_HZ_COMMON
+/*
+ * There is no sane way to deal with nohz on smp when using jiffies because the
+ * cpu doing the jiffies update might drift wrt the cpu doing the jiffy reading
+ * causing off-by-one errors in observed deltas; {0,2} instead of {1,1}.
+ *
+ * Therefore we cannot use the delta approach from the regular tick since that
+ * would seriously skew the load calculation. However we'll make do for those
+ * updates happening while idle (nohz_idle_balance) or coming out of idle
+ * (tick_nohz_idle_exit).
+ *
+ * This means we might still be one tick off for nohz periods.
+ */
+
+/*
+ * Called from nohz_idle_balance() to update the load ratings before doing the
+ * idle balance.
+ */
+void update_idle_cpu_load(struct rq *this_rq)
+{
+ unsigned long curr_jiffies = ACCESS_ONCE(jiffies);
+ unsigned long load = this_rq->load.weight;
+ unsigned long pending_updates;
+
+ /*
+ * bail if there's load or we're actually up-to-date.
+ */
+ if (load || curr_jiffies == this_rq->last_load_update_tick)
+ return;
+
+ pending_updates = curr_jiffies - this_rq->last_load_update_tick;
+ this_rq->last_load_update_tick = curr_jiffies;
+
+ __update_cpu_load(this_rq, load, pending_updates);
+}
+
+/*
+ * Called from tick_nohz_idle_exit() -- try and fix up the ticks we missed.
+ */
+void update_cpu_load_nohz(void)
+{
+ struct rq *this_rq = this_rq();
+ unsigned long curr_jiffies = ACCESS_ONCE(jiffies);
+ unsigned long pending_updates;
+
+ if (curr_jiffies == this_rq->last_load_update_tick)
+ return;
+
+ raw_spin_lock(&this_rq->lock);
+ pending_updates = curr_jiffies - this_rq->last_load_update_tick;
+ if (pending_updates) {
+ this_rq->last_load_update_tick = curr_jiffies;
+ /*
+ * We were idle, this means load 0, the current load might be
+ * !0 due to remote wakeups and the sort.
+ */
+ __update_cpu_load(this_rq, 0, pending_updates);
+ }
+ raw_spin_unlock(&this_rq->lock);
+}
+#endif /* CONFIG_NO_HZ */
+
+/*
+ * Called from scheduler_tick()
+ */
+void update_cpu_load_active(struct rq *this_rq)
+{
+ /*
+ * See the mess around update_idle_cpu_load() / update_cpu_load_nohz().
+ */
+ this_rq->last_load_update_tick = jiffies;
+ __update_cpu_load(this_rq, this_rq->load.weight, 1);
+
+ calc_load_account_active(this_rq);
+}
#ifdef CONFIG_SMP
static inline const struct cpumask *sched_rt_period_mask(void)
{
- return cpu_rq(smp_processor_id())->rd->span;
+ return this_rq()->rd->span;
}
#else
static inline const struct cpumask *sched_rt_period_mask(void)
}
}
-static void disable_runtime(struct rq *rq)
-{
- unsigned long flags;
-
- raw_spin_lock_irqsave(&rq->lock, flags);
- __disable_runtime(rq);
- raw_spin_unlock_irqrestore(&rq->lock, flags);
-}
-
static void __enable_runtime(struct rq *rq)
{
rt_rq_iter_t iter;
}
}
-static void enable_runtime(struct rq *rq)
-{
- unsigned long flags;
-
- raw_spin_lock_irqsave(&rq->lock, flags);
- __enable_runtime(rq);
- raw_spin_unlock_irqrestore(&rq->lock, flags);
-}
-
-int update_runtime(struct notifier_block *nfb, unsigned long action, void *hcpu)
-{
- int cpu = (int)(long)hcpu;
-
- switch (action) {
- case CPU_DOWN_PREPARE:
- case CPU_DOWN_PREPARE_FROZEN:
- disable_runtime(cpu_rq(cpu));
- return NOTIFY_OK;
-
- case CPU_DOWN_FAILED:
- case CPU_DOWN_FAILED_FROZEN:
- case CPU_ONLINE:
- case CPU_ONLINE_FROZEN:
- enable_runtime(cpu_rq(cpu));
- return NOTIFY_OK;
-
- default:
- return NOTIFY_DONE;
- }
-}
-
static int balance_runtime(struct rt_rq *rt_rq)
{
int more = 0;
if (curr->sched_class != &rt_sched_class)
return;
- delta_exec = rq->clock_task - curr->se.exec_start;
+ delta_exec = rq_clock_task(rq) - curr->se.exec_start;
if (unlikely((s64)delta_exec <= 0))
return;
curr->se.sum_exec_runtime += delta_exec;
account_group_exec_runtime(curr, delta_exec);
- curr->se.exec_start = rq->clock_task;
+ curr->se.exec_start = rq_clock_task(rq);
cpuacct_charge(curr, delta_exec);
sched_rt_avg_update(rq, delta_exec);
} while (rt_rq);
p = rt_task_of(rt_se);
- p->se.exec_start = rq->clock_task;
+ p->se.exec_start = rq_clock_task(rq);
return p;
}
{
struct task_struct *p = rq->curr;
- p->se.exec_start = rq->clock_task;
+ p->se.exec_start = rq_clock_task(rq);
/* The running task is never eligible for pushing */
dequeue_pushable_task(rq, p);
#include "cpupri.h"
#include "cpuacct.h"
+struct rq;
+
extern __read_mostly int scheduler_running;
+extern unsigned long calc_load_update;
+extern atomic_long_t calc_load_tasks;
+
+extern long calc_load_fold_active(struct rq *this_rq);
+extern void update_cpu_load_active(struct rq *this_rq);
+
/*
* Convert user-nice values [ -20 ... 0 ... 19 ]
* to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ],
#define cpu_curr(cpu) (cpu_rq(cpu)->curr)
#define raw_rq() (&__raw_get_cpu_var(runqueues))
+static inline u64 rq_clock(struct rq *rq)
+{
+ return rq->clock;
+}
+
+static inline u64 rq_clock_task(struct rq *rq)
+{
+ return rq->clock_task;
+}
+
#ifdef CONFIG_SMP
#define rcu_dereference_check_sched_domain(p) \
#define WF_FORK 0x02 /* child wakeup after fork */
#define WF_MIGRATED 0x4 /* internal use, task got migrated */
-static inline void update_load_add(struct load_weight *lw, unsigned long inc)
-{
- lw->weight += inc;
- lw->inv_weight = 0;
-}
-
-static inline void update_load_sub(struct load_weight *lw, unsigned long dec)
-{
- lw->weight -= dec;
- lw->inv_weight = 0;
-}
-
-static inline void update_load_set(struct load_weight *lw, unsigned long w)
-{
- lw->weight = w;
- lw->inv_weight = 0;
-}
-
/*
* To aid in avoiding the subversion of "niceness" due to uneven distribution
* of tasks with abnormal "nice" values across CPUs the contribution that
extern void sysrq_sched_debug_show(void);
extern void sched_init_granularity(void);
extern void update_max_interval(void);
-extern int update_runtime(struct notifier_block *nfb, unsigned long action, void *hcpu);
extern void init_sched_rt_class(void);
extern void init_sched_fair_class(void);
*/
static inline void sched_info_dequeued(struct task_struct *t)
{
- unsigned long long now = task_rq(t)->clock, delta = 0;
+ unsigned long long now = rq_clock(task_rq(t)), delta = 0;
if (unlikely(sched_info_on()))
if (t->sched_info.last_queued)
*/
static void sched_info_arrive(struct task_struct *t)
{
- unsigned long long now = task_rq(t)->clock, delta = 0;
+ unsigned long long now = rq_clock(task_rq(t)), delta = 0;
if (t->sched_info.last_queued)
delta = now - t->sched_info.last_queued;
{
if (unlikely(sched_info_on()))
if (!t->sched_info.last_queued)
- t->sched_info.last_queued = task_rq(t)->clock;
+ t->sched_info.last_queued = rq_clock(task_rq(t));
}
/*
*/
static inline void sched_info_depart(struct task_struct *t)
{
- unsigned long long delta = task_rq(t)->clock -
+ unsigned long long delta = rq_clock(task_rq(t)) -
t->sched_info.last_arrival;
rq_sched_info_depart(task_rq(t), delta);
struct task_struct *stop = rq->stop;
if (stop && stop->on_rq) {
- stop->se.exec_start = rq->clock_task;
+ stop->se.exec_start = rq_clock_task(rq);
return stop;
}
struct task_struct *curr = rq->curr;
u64 delta_exec;
- delta_exec = rq->clock_task - curr->se.exec_start;
+ delta_exec = rq_clock_task(rq) - curr->se.exec_start;
if (unlikely((s64)delta_exec < 0))
delta_exec = 0;
curr->se.sum_exec_runtime += delta_exec;
account_group_exec_runtime(curr, delta_exec);
- curr->se.exec_start = rq->clock_task;
+ curr->se.exec_start = rq_clock_task(rq);
cpuacct_charge(curr, delta_exec);
}
{
struct task_struct *stop = rq->stop;
- stop->se.exec_start = rq->clock_task;
+ stop->se.exec_start = rq_clock_task(rq);
}
static void switched_to_stop(struct rq *rq, struct task_struct *p)
projects / cascardo / linux.git / commitdiff