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-rw-r--r--kernel/sched/fair.c867
1 files changed, 420 insertions, 447 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index dea138964b91..008c514dc241 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -369,8 +369,9 @@ static inline void list_del_leaf_cfs_rq(struct cfs_rq *cfs_rq)
}
/* Iterate thr' all leaf cfs_rq's on a runqueue */
-#define for_each_leaf_cfs_rq(rq, cfs_rq) \
- list_for_each_entry_rcu(cfs_rq, &rq->leaf_cfs_rq_list, leaf_cfs_rq_list)
+#define for_each_leaf_cfs_rq_safe(rq, cfs_rq, pos) \
+ list_for_each_entry_safe(cfs_rq, pos, &rq->leaf_cfs_rq_list, \
+ leaf_cfs_rq_list)
/* Do the two (enqueued) entities belong to the same group ? */
static inline struct cfs_rq *
@@ -463,8 +464,8 @@ static inline void list_del_leaf_cfs_rq(struct cfs_rq *cfs_rq)
{
}
-#define for_each_leaf_cfs_rq(rq, cfs_rq) \
- for (cfs_rq = &rq->cfs; cfs_rq; cfs_rq = NULL)
+#define for_each_leaf_cfs_rq_safe(rq, cfs_rq, pos) \
+ for (cfs_rq = &rq->cfs, pos = NULL; cfs_rq; cfs_rq = pos)
static inline struct sched_entity *parent_entity(struct sched_entity *se)
{
@@ -717,18 +718,12 @@ static u64 sched_vslice(struct cfs_rq *cfs_rq, struct sched_entity *se)
}
#ifdef CONFIG_SMP
+
+#include "sched-pelt.h"
+
static int select_idle_sibling(struct task_struct *p, int prev_cpu, int cpu);
static unsigned long task_h_load(struct task_struct *p);
-/*
- * We choose a half-life close to 1 scheduling period.
- * Note: The tables runnable_avg_yN_inv and runnable_avg_yN_sum are
- * dependent on this value.
- */
-#define LOAD_AVG_PERIOD 32
-#define LOAD_AVG_MAX 47742 /* maximum possible load avg */
-#define LOAD_AVG_MAX_N 345 /* number of full periods to produce LOAD_AVG_MAX */
-
/* Give new sched_entity start runnable values to heavy its load in infant time */
void init_entity_runnable_average(struct sched_entity *se)
{
@@ -1387,7 +1382,6 @@ static unsigned long weighted_cpuload(const int cpu);
static unsigned long source_load(int cpu, int type);
static unsigned long target_load(int cpu, int type);
static unsigned long capacity_of(int cpu);
-static long effective_load(struct task_group *tg, int cpu, long wl, long wg);
/* Cached statistics for all CPUs within a node */
struct numa_stats {
@@ -2475,7 +2469,8 @@ void task_numa_work(struct callback_head *work)
return;
- down_read(&mm->mmap_sem);
+ if (!down_read_trylock(&mm->mmap_sem))
+ return;
vma = find_vma(mm, start);
if (!vma) {
reset_ptenuma_scan(p);
@@ -2590,6 +2585,60 @@ void task_tick_numa(struct rq *rq, struct task_struct *curr)
}
}
}
+
+/*
+ * Can a task be moved from prev_cpu to this_cpu without causing a load
+ * imbalance that would trigger the load balancer?
+ */
+static inline bool numa_wake_affine(struct sched_domain *sd,
+ struct task_struct *p, int this_cpu,
+ int prev_cpu, int sync)
+{
+ struct numa_stats prev_load, this_load;
+ s64 this_eff_load, prev_eff_load;
+
+ update_numa_stats(&prev_load, cpu_to_node(prev_cpu));
+ update_numa_stats(&this_load, cpu_to_node(this_cpu));
+
+ /*
+ * If sync wakeup then subtract the (maximum possible)
+ * effect of the currently running task from the load
+ * of the current CPU:
+ */
+ if (sync) {
+ unsigned long current_load = task_h_load(current);
+
+ if (this_load.load > current_load)
+ this_load.load -= current_load;
+ else
+ this_load.load = 0;
+ }
+
+ /*
+ * In low-load situations, where this_cpu's node is idle due to the
+ * sync cause above having dropped this_load.load to 0, move the task.
+ * Moving to an idle socket will not create a bad imbalance.
+ *
+ * Otherwise check if the nodes are near enough in load to allow this
+ * task to be woken on this_cpu's node.
+ */
+ if (this_load.load > 0) {
+ unsigned long task_load = task_h_load(p);
+
+ this_eff_load = 100;
+ this_eff_load *= prev_load.compute_capacity;
+
+ prev_eff_load = 100 + (sd->imbalance_pct - 100) / 2;
+ prev_eff_load *= this_load.compute_capacity;
+
+ this_eff_load *= this_load.load + task_load;
+ prev_eff_load *= prev_load.load - task_load;
+
+ return this_eff_load <= prev_eff_load;
+ }
+
+ return true;
+}
#else
static void task_tick_numa(struct rq *rq, struct task_struct *curr)
{
@@ -2602,6 +2651,15 @@ static inline void account_numa_enqueue(struct rq *rq, struct task_struct *p)
static inline void account_numa_dequeue(struct rq *rq, struct task_struct *p)
{
}
+
+#ifdef CONFIG_SMP
+static inline bool numa_wake_affine(struct sched_domain *sd,
+ struct task_struct *p, int this_cpu,
+ int prev_cpu, int sync)
+{
+ return true;
+}
+#endif /* !SMP */
#endif /* CONFIG_NUMA_BALANCING */
static void
@@ -2733,47 +2791,15 @@ static inline void update_cfs_shares(struct sched_entity *se)
#endif /* CONFIG_FAIR_GROUP_SCHED */
#ifdef CONFIG_SMP
-/* Precomputed fixed inverse multiplies for multiplication by y^n */
-static const u32 runnable_avg_yN_inv[] = {
- 0xffffffff, 0xfa83b2da, 0xf5257d14, 0xefe4b99a, 0xeac0c6e6, 0xe5b906e6,
- 0xe0ccdeeb, 0xdbfbb796, 0xd744fcc9, 0xd2a81d91, 0xce248c14, 0xc9b9bd85,
- 0xc5672a10, 0xc12c4cc9, 0xbd08a39e, 0xb8fbaf46, 0xb504f333, 0xb123f581,
- 0xad583ee9, 0xa9a15ab4, 0xa5fed6a9, 0xa2704302, 0x9ef5325f, 0x9b8d39b9,
- 0x9837f050, 0x94f4efa8, 0x91c3d373, 0x8ea4398a, 0x8b95c1e3, 0x88980e80,
- 0x85aac367, 0x82cd8698,
-};
-
-/*
- * Precomputed \Sum y^k { 1<=k<=n }. These are floor(true_value) to prevent
- * over-estimates when re-combining.
- */
-static const u32 runnable_avg_yN_sum[] = {
- 0, 1002, 1982, 2941, 3880, 4798, 5697, 6576, 7437, 8279, 9103,
- 9909,10698,11470,12226,12966,13690,14398,15091,15769,16433,17082,
- 17718,18340,18949,19545,20128,20698,21256,21802,22336,22859,23371,
-};
-
-/*
- * Precomputed \Sum y^k { 1<=k<=n, where n%32=0). Values are rolled down to
- * lower integers. See Documentation/scheduler/sched-avg.txt how these
- * were generated:
- */
-static const u32 __accumulated_sum_N32[] = {
- 0, 23371, 35056, 40899, 43820, 45281,
- 46011, 46376, 46559, 46650, 46696, 46719,
-};
-
/*
* Approximate:
* val * y^n, where y^32 ~= 0.5 (~1 scheduling period)
*/
-static __always_inline u64 decay_load(u64 val, u64 n)
+static u64 decay_load(u64 val, u64 n)
{
unsigned int local_n;
- if (!n)
- return val;
- else if (unlikely(n > LOAD_AVG_PERIOD * 63))
+ if (unlikely(n > LOAD_AVG_PERIOD * 63))
return 0;
/* after bounds checking we can collapse to 32-bit */
@@ -2795,30 +2821,97 @@ static __always_inline u64 decay_load(u64 val, u64 n)
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;
+}
+
+#define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
+
/*
- * For updates fully spanning n periods, the contribution to runnable
- * average will be: \Sum 1024*y^n
+ * 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)
*
- * We can compute this reasonably efficiently by combining:
- * y^PERIOD = 1/2 with precomputed \Sum 1024*y^n {for n <PERIOD}
+ * p-1
+ * d1 y^p + 1024 \Sum y^n + d3 y^0 (Step 2)
+ * n=1
*/
-static u32 __compute_runnable_contrib(u64 n)
+static __always_inline u32
+accumulate_sum(u64 delta, int cpu, struct sched_avg *sa,
+ unsigned long weight, int running, struct cfs_rq *cfs_rq)
{
- u32 contrib = 0;
+ unsigned long scale_freq, scale_cpu;
+ u32 contrib = (u32)delta; /* p == 0 -> delta < 1024 */
+ u64 periods;
- if (likely(n <= LOAD_AVG_PERIOD))
- return runnable_avg_yN_sum[n];
- else if (unlikely(n >= LOAD_AVG_MAX_N))
- return LOAD_AVG_MAX;
+ scale_freq = arch_scale_freq_capacity(NULL, cpu);
+ scale_cpu = arch_scale_cpu_capacity(NULL, cpu);
- /* Since n < LOAD_AVG_MAX_N, n/LOAD_AVG_PERIOD < 11 */
- contrib = __accumulated_sum_N32[n/LOAD_AVG_PERIOD];
- n %= LOAD_AVG_PERIOD;
- contrib = decay_load(contrib, n);
- return contrib + runnable_avg_yN_sum[n];
-}
+ delta += sa->period_contrib;
+ periods = delta / 1024; /* A period is 1024us (~1ms) */
-#define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
+ /*
+ * Step 1: decay old *_sum if we crossed period boundaries.
+ */
+ if (periods) {
+ sa->load_sum = decay_load(sa->load_sum, periods);
+ if (cfs_rq) {
+ cfs_rq->runnable_load_sum =
+ decay_load(cfs_rq->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 (weight) {
+ sa->load_sum += weight * contrib;
+ if (cfs_rq)
+ cfs_rq->runnable_load_sum += weight * contrib;
+ }
+ if (running)
+ sa->util_sum += contrib * scale_cpu;
+
+ return periods;
+}
/*
* We can represent the historical contribution to runnable average as the
@@ -2849,13 +2942,10 @@ static u32 __compute_runnable_contrib(u64 n)
* = u_0 + u_1*y + u_2*y^2 + ... [re-labeling u_i --> u_{i+1}]
*/
static __always_inline int
-__update_load_avg(u64 now, int cpu, struct sched_avg *sa,
+___update_load_avg(u64 now, int cpu, struct sched_avg *sa,
unsigned long weight, int running, struct cfs_rq *cfs_rq)
{
- u64 delta, scaled_delta, periods;
- u32 contrib;
- unsigned int delta_w, scaled_delta_w, decayed = 0;
- unsigned long scale_freq, scale_cpu;
+ u64 delta;
delta = now - sa->last_update_time;
/*
@@ -2874,83 +2964,52 @@ __update_load_avg(u64 now, int cpu, struct sched_avg *sa,
delta >>= 10;
if (!delta)
return 0;
- sa->last_update_time = now;
-
- scale_freq = arch_scale_freq_capacity(NULL, cpu);
- scale_cpu = arch_scale_cpu_capacity(NULL, cpu);
-
- /* delta_w is the amount already accumulated against our next period */
- delta_w = sa->period_contrib;
- if (delta + delta_w >= 1024) {
- decayed = 1;
-
- /* how much left for next period will start over, we don't know yet */
- sa->period_contrib = 0;
-
- /*
- * Now that we know we're crossing a period boundary, figure
- * out how much from delta we need to complete the current
- * period and accrue it.
- */
- delta_w = 1024 - delta_w;
- scaled_delta_w = cap_scale(delta_w, scale_freq);
- if (weight) {
- sa->load_sum += weight * scaled_delta_w;
- if (cfs_rq) {
- cfs_rq->runnable_load_sum +=
- weight * scaled_delta_w;
- }
- }
- if (running)
- sa->util_sum += scaled_delta_w * scale_cpu;
- delta -= delta_w;
+ sa->last_update_time += delta << 10;
- /* Figure out how many additional periods this update spans */
- periods = delta / 1024;
- delta %= 1024;
+ /*
+ * 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, weight, running, cfs_rq))
+ return 0;
- sa->load_sum = decay_load(sa->load_sum, periods + 1);
- if (cfs_rq) {
- cfs_rq->runnable_load_sum =
- decay_load(cfs_rq->runnable_load_sum, periods + 1);
- }
- sa->util_sum = decay_load((u64)(sa->util_sum), periods + 1);
-
- /* Efficiently calculate \sum (1..n_period) 1024*y^i */
- contrib = __compute_runnable_contrib(periods);
- contrib = cap_scale(contrib, scale_freq);
- if (weight) {
- sa->load_sum += weight * contrib;
- if (cfs_rq)
- cfs_rq->runnable_load_sum += weight * contrib;
- }
- if (running)
- sa->util_sum += contrib * scale_cpu;
+ /*
+ * Step 2: update *_avg.
+ */
+ sa->load_avg = div_u64(sa->load_sum, LOAD_AVG_MAX - 1024 + sa->period_contrib);
+ if (cfs_rq) {
+ cfs_rq->runnable_load_avg =
+ div_u64(cfs_rq->runnable_load_sum, LOAD_AVG_MAX - 1024 + sa->period_contrib);
}
+ sa->util_avg = sa->util_sum / (LOAD_AVG_MAX - 1024 + sa->period_contrib);
- /* Remainder of delta accrued against u_0` */
- scaled_delta = cap_scale(delta, scale_freq);
- if (weight) {
- sa->load_sum += weight * scaled_delta;
- if (cfs_rq)
- cfs_rq->runnable_load_sum += weight * scaled_delta;
- }
- if (running)
- sa->util_sum += scaled_delta * scale_cpu;
+ return 1;
+}
- sa->period_contrib += delta;
+static int
+__update_load_avg_blocked_se(u64 now, int cpu, struct sched_entity *se)
+{
+ return ___update_load_avg(now, cpu, &se->avg, 0, 0, NULL);
+}
- if (decayed) {
- sa->load_avg = div_u64(sa->load_sum, LOAD_AVG_MAX);
- if (cfs_rq) {
- cfs_rq->runnable_load_avg =
- div_u64(cfs_rq->runnable_load_sum, LOAD_AVG_MAX);
- }
- sa->util_avg = sa->util_sum / LOAD_AVG_MAX;
- }
+static int
+__update_load_avg_se(u64 now, int cpu, struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+ return ___update_load_avg(now, cpu, &se->avg,
+ se->on_rq * scale_load_down(se->load.weight),
+ cfs_rq->curr == se, NULL);
+}
- return decayed;
+static int
+__update_load_avg_cfs_rq(u64 now, int cpu, struct cfs_rq *cfs_rq)
+{
+ return ___update_load_avg(now, cpu, &cfs_rq->avg,
+ scale_load_down(cfs_rq->load.weight),
+ cfs_rq->curr != NULL, cfs_rq);
}
/*
@@ -2987,8 +3046,7 @@ __update_load_avg(u64 now, int cpu, struct sched_avg *sa,
* differential update where we store the last value we propagated. This in
* turn allows skipping updates if the differential is 'small'.
*
- * Updating tg's load_avg is necessary before update_cfs_share() (which is
- * done) and effective_load() (which is not done because it is too costly).
+ * Updating tg's load_avg is necessary before update_cfs_share().
*/
static inline void update_tg_load_avg(struct cfs_rq *cfs_rq, int force)
{
@@ -3014,6 +3072,9 @@ static inline void update_tg_load_avg(struct cfs_rq *cfs_rq, int force)
void set_task_rq_fair(struct sched_entity *se,
struct cfs_rq *prev, struct cfs_rq *next)
{
+ u64 p_last_update_time;
+ u64 n_last_update_time;
+
if (!sched_feat(ATTACH_AGE_LOAD))
return;
@@ -3024,11 +3085,11 @@ void set_task_rq_fair(struct sched_entity *se,
* time. This will result in the wakee task is less decayed, but giving
* the wakee more load sounds not bad.
*/
- if (se->avg.last_update_time && prev) {
- u64 p_last_update_time;
- u64 n_last_update_time;
+ if (!(se->avg.last_update_time && prev))
+ return;
#ifndef CONFIG_64BIT
+ {
u64 p_last_update_time_copy;
u64 n_last_update_time_copy;
@@ -3043,14 +3104,13 @@ void set_task_rq_fair(struct sched_entity *se,
} while (p_last_update_time != p_last_update_time_copy ||
n_last_update_time != n_last_update_time_copy);
+ }
#else
- p_last_update_time = prev->avg.last_update_time;
- n_last_update_time = next->avg.last_update_time;
+ p_last_update_time = prev->avg.last_update_time;
+ n_last_update_time = next->avg.last_update_time;
#endif
- __update_load_avg(p_last_update_time, cpu_of(rq_of(prev)),
- &se->avg, 0, 0, NULL);
- se->avg.last_update_time = n_last_update_time;
- }
+ __update_load_avg_blocked_se(p_last_update_time, cpu_of(rq_of(prev)), se);
+ se->avg.last_update_time = n_last_update_time;
}
/* Take into account change of utilization of a child task group */
@@ -3173,6 +3233,36 @@ static inline int propagate_entity_load_avg(struct sched_entity *se)
return 1;
}
+/*
+ * Check if we need to update the load and the utilization of a blocked
+ * group_entity:
+ */
+static inline bool skip_blocked_update(struct sched_entity *se)
+{
+ struct cfs_rq *gcfs_rq = group_cfs_rq(se);
+
+ /*
+ * If sched_entity still have not zero load or utilization, we have to
+ * decay it:
+ */
+ if (se->avg.load_avg || se->avg.util_avg)
+ return false;
+
+ /*
+ * If there is a pending propagation, we have to update the load and
+ * the utilization of the sched_entity:
+ */
+ if (gcfs_rq->propagate_avg)
+ return false;
+
+ /*
+ * Otherwise, the load and the utilization of the sched_entity is
+ * already zero and there is no pending propagation, so it will be a
+ * waste of time to try to decay it:
+ */
+ return true;
+}
+
#else /* CONFIG_FAIR_GROUP_SCHED */
static inline void update_tg_load_avg(struct cfs_rq *cfs_rq, int force) {}
@@ -3265,8 +3355,7 @@ update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq, bool update_freq)
set_tg_cfs_propagate(cfs_rq);
}
- decayed = __update_load_avg(now, cpu_of(rq_of(cfs_rq)), sa,
- scale_load_down(cfs_rq->load.weight), cfs_rq->curr != NULL, cfs_rq);
+ decayed = __update_load_avg_cfs_rq(now, cpu_of(rq_of(cfs_rq)), cfs_rq);
#ifndef CONFIG_64BIT
smp_wmb();
@@ -3298,11 +3387,8 @@ static inline void update_load_avg(struct sched_entity *se, int flags)
* Track task load average for carrying it to new CPU after migrated, and
* track group sched_entity load average for task_h_load calc in migration
*/
- if (se->avg.last_update_time && !(flags & SKIP_AGE_LOAD)) {
- __update_load_avg(now, cpu, &se->avg,
- se->on_rq * scale_load_down(se->load.weight),
- cfs_rq->curr == se, NULL);
- }
+ if (se->avg.last_update_time && !(flags & SKIP_AGE_LOAD))
+ __update_load_avg_se(now, cpu, cfs_rq, se);
decayed = update_cfs_rq_load_avg(now, cfs_rq, true);
decayed |= propagate_entity_load_avg(se);
@@ -3407,7 +3493,7 @@ void sync_entity_load_avg(struct sched_entity *se)
u64 last_update_time;
last_update_time = cfs_rq_last_update_time(cfs_rq);
- __update_load_avg(last_update_time, cpu_of(rq_of(cfs_rq)), &se->avg, 0, 0, NULL);
+ __update_load_avg_blocked_se(last_update_time, cpu_of(rq_of(cfs_rq)), se);
}
/*
@@ -3540,7 +3626,7 @@ static inline void check_schedstat_required(void)
trace_sched_stat_runtime_enabled()) {
printk_deferred_once("Scheduler tracepoints stat_sleep, stat_iowait, "
"stat_blocked and stat_runtime require the "
- "kernel parameter schedstats=enabled or "
+ "kernel parameter schedstats=enable or "
"kernel.sched_schedstats=1\n");
}
#endif
@@ -4271,8 +4357,9 @@ static u64 distribute_cfs_runtime(struct cfs_bandwidth *cfs_b,
list_for_each_entry_rcu(cfs_rq, &cfs_b->throttled_cfs_rq,
throttled_list) {
struct rq *rq = rq_of(cfs_rq);
+ struct rq_flags rf;
- raw_spin_lock(&rq->lock);
+ rq_lock(rq, &rf);
if (!cfs_rq_throttled(cfs_rq))
goto next;
@@ -4289,7 +4376,7 @@ static u64 distribute_cfs_runtime(struct cfs_bandwidth *cfs_b,
unthrottle_cfs_rq(cfs_rq);
next:
- raw_spin_unlock(&rq->lock);
+ rq_unlock(rq, &rf);
if (!remaining)
break;
@@ -4618,24 +4705,43 @@ static void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
hrtimer_cancel(&cfs_b->slack_timer);
}
+/*
+ * Both these cpu hotplug callbacks race against unregister_fair_sched_group()
+ *
+ * The race is harmless, since modifying bandwidth settings of unhooked group
+ * bits doesn't do much.
+ */
+
+/* cpu online calback */
static void __maybe_unused update_runtime_enabled(struct rq *rq)
{
- struct cfs_rq *cfs_rq;
+ struct task_group *tg;
+
+ lockdep_assert_held(&rq->lock);
- for_each_leaf_cfs_rq(rq, cfs_rq) {
- struct cfs_bandwidth *cfs_b = &cfs_rq->tg->cfs_bandwidth;
+ rcu_read_lock();
+ list_for_each_entry_rcu(tg, &task_groups, list) {
+ struct cfs_bandwidth *cfs_b = &tg->cfs_bandwidth;
+ struct cfs_rq *cfs_rq = tg->cfs_rq[cpu_of(rq)];
raw_spin_lock(&cfs_b->lock);
cfs_rq->runtime_enabled = cfs_b->quota != RUNTIME_INF;
raw_spin_unlock(&cfs_b->lock);
}
+ rcu_read_unlock();
}
+/* cpu offline callback */
static void __maybe_unused unthrottle_offline_cfs_rqs(struct rq *rq)
{
- struct cfs_rq *cfs_rq;
+ struct task_group *tg;
+
+ lockdep_assert_held(&rq->lock);
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(tg, &task_groups, list) {
+ struct cfs_rq *cfs_rq = tg->cfs_rq[cpu_of(rq)];
- for_each_leaf_cfs_rq(rq, cfs_rq) {
if (!cfs_rq->runtime_enabled)
continue;
@@ -4653,6 +4759,7 @@ static void __maybe_unused unthrottle_offline_cfs_rqs(struct rq *rq)
if (cfs_rq_throttled(cfs_rq))
unthrottle_cfs_rq(cfs_rq);
}
+ rcu_read_unlock();
}
#else /* CONFIG_CFS_BANDWIDTH */
@@ -5097,15 +5204,16 @@ void cpu_load_update_nohz_stop(void)
unsigned long curr_jiffies = READ_ONCE(jiffies);
struct rq *this_rq = this_rq();
unsigned long load;
+ struct rq_flags rf;
if (curr_jiffies == this_rq->last_load_update_tick)
return;
load = weighted_cpuload(cpu_of(this_rq));
- raw_spin_lock(&this_rq->lock);
+ rq_lock(this_rq, &rf);
update_rq_clock(this_rq);
cpu_load_update_nohz(this_rq, curr_jiffies, load);
- raw_spin_unlock(&this_rq->lock);
+ rq_unlock(this_rq, &rf);
}
#else /* !CONFIG_NO_HZ_COMMON */
static inline void cpu_load_update_nohz(struct rq *this_rq,
@@ -5190,126 +5298,6 @@ static unsigned long cpu_avg_load_per_task(int cpu)
return 0;
}
-#ifdef CONFIG_FAIR_GROUP_SCHED
-/*
- * effective_load() calculates the load change as seen from the root_task_group
- *
- * Adding load to a group doesn't make a group heavier, but can cause movement
- * of group shares between cpus. Assuming the shares were perfectly aligned one
- * can calculate the shift in shares.
- *
- * Calculate the effective load difference if @wl is added (subtracted) to @tg
- * on this @cpu and results in a total addition (subtraction) of @wg to the
- * total group weight.
- *
- * Given a runqueue weight distribution (rw_i) we can compute a shares
- * distribution (s_i) using:
- *
- * s_i = rw_i / \Sum rw_j (1)
- *
- * Suppose we have 4 CPUs and our @tg is a direct child of the root group and
- * has 7 equal weight tasks, distributed as below (rw_i), with the resulting
- * shares distribution (s_i):
- *
- * rw_i = { 2, 4, 1, 0 }
- * s_i = { 2/7, 4/7, 1/7, 0 }
- *
- * As per wake_affine() we're interested in the load of two CPUs (the CPU the
- * task used to run on and the CPU the waker is running on), we need to
- * compute the effect of waking a task on either CPU and, in case of a sync
- * wakeup, compute the effect of the current task going to sleep.
- *
- * So for a change of @wl to the local @cpu with an overall group weight change
- * of @wl we can compute the new shares distribution (s'_i) using:
- *
- * s'_i = (rw_i + @wl) / (@wg + \Sum rw_j) (2)
- *
- * Suppose we're interested in CPUs 0 and 1, and want to compute the load
- * differences in waking a task to CPU 0. The additional task changes the
- * weight and shares distributions like:
- *
- * rw'_i = { 3, 4, 1, 0 }
- * s'_i = { 3/8, 4/8, 1/8, 0 }
- *
- * We can then compute the difference in effective weight by using:
- *
- * dw_i = S * (s'_i - s_i) (3)
- *
- * Where 'S' is the group weight as seen by its parent.
- *
- * Therefore the effective change in loads on CPU 0 would be 5/56 (3/8 - 2/7)
- * times the weight of the group. The effect on CPU 1 would be -4/56 (4/8 -
- * 4/7) times the weight of the group.
- */
-static long effective_load(struct task_group *tg, int cpu, long wl, long wg)
-{
- struct sched_entity *se = tg->se[cpu];
-
- if (!tg->parent) /* the trivial, non-cgroup case */
- return wl;
-
- for_each_sched_entity(se) {
- struct cfs_rq *cfs_rq = se->my_q;
- long W, w = cfs_rq_load_avg(cfs_rq);
-
- tg = cfs_rq->tg;
-
- /*
- * W = @wg + \Sum rw_j
- */
- W = wg + atomic_long_read(&tg->load_avg);
-
- /* Ensure \Sum rw_j >= rw_i */
- W -= cfs_rq->tg_load_avg_contrib;
- W += w;
-
- /*
- * w = rw_i + @wl
- */
- w += wl;
-
- /*
- * wl = S * s'_i; see (2)
- */
- if (W > 0 && w < W)
- wl = (w * (long)scale_load_down(tg->shares)) / W;
- else
- wl = scale_load_down(tg->shares);
-
- /*
- * Per the above, wl is the new se->load.weight value; since
- * those are clipped to [MIN_SHARES, ...) do so now. See
- * calc_cfs_shares().
- */
- if (wl < MIN_SHARES)
- wl = MIN_SHARES;
-
- /*
- * wl = dw_i = S * (s'_i - s_i); see (3)
- */
- wl -= se->avg.load_avg;
-
- /*
- * Recursively apply this logic to all parent groups to compute
- * the final effective load change on the root group. Since
- * only the @tg group gets extra weight, all parent groups can
- * only redistribute existing shares. @wl is the shift in shares
- * resulting from this level per the above.
- */
- wg = 0;
- }
-
- return wl;
-}
-#else
-
-static long effective_load(struct task_group *tg, int cpu, long wl, long wg)
-{
- return wl;
-}
-
-#endif
-
static void record_wakee(struct task_struct *p)
{
/*
@@ -5360,67 +5348,25 @@ static int wake_wide(struct task_struct *p)
static int wake_affine(struct sched_domain *sd, struct task_struct *p,
int prev_cpu, int sync)
{
- s64 this_load, load;
- s64 this_eff_load, prev_eff_load;
- int idx, this_cpu;
- struct task_group *tg;
- unsigned long weight;
- int balanced;
-
- idx = sd->wake_idx;
- this_cpu = smp_processor_id();
- load = source_load(prev_cpu, idx);
- this_load = target_load(this_cpu, idx);
+ int this_cpu = smp_processor_id();
+ bool affine = false;
/*
- * If sync wakeup then subtract the (maximum possible)
- * effect of the currently running task from the load
- * of the current CPU:
+ * Common case: CPUs are in the same socket, and select_idle_sibling()
+ * will do its thing regardless of what we return:
*/
- if (sync) {
- tg = task_group(current);
- weight = current->se.avg.load_avg;
-
- this_load += effective_load(tg, this_cpu, -weight, -weight);
- load += effective_load(tg, prev_cpu, 0, -weight);
- }
-
- tg = task_group(p);
- weight = p->se.avg.load_avg;
-
- /*
- * In low-load situations, where prev_cpu is idle and this_cpu is idle
- * due to the sync cause above having dropped this_load to 0, we'll
- * always have an imbalance, but there's really nothing you can do
- * about that, so that's good too.
- *
- * Otherwise check if either cpus are near enough in load to allow this
- * task to be woken on this_cpu.
- */
- this_eff_load = 100;
- this_eff_load *= capacity_of(prev_cpu);
-
- prev_eff_load = 100 + (sd->imbalance_pct - 100) / 2;
- prev_eff_load *= capacity_of(this_cpu);
-
- if (this_load > 0) {
- this_eff_load *= this_load +
- effective_load(tg, this_cpu, weight, weight);
-
- prev_eff_load *= load + effective_load(tg, prev_cpu, 0, weight);
- }
-
- balanced = this_eff_load <= prev_eff_load;
+ if (cpus_share_cache(prev_cpu, this_cpu))
+ affine = true;
+ else
+ affine = numa_wake_affine(sd, p, this_cpu, prev_cpu, sync);
schedstat_inc(p->se.statistics.nr_wakeups_affine_attempts);
+ if (affine) {
+ schedstat_inc(sd->ttwu_move_affine);
+ schedstat_inc(p->se.statistics.nr_wakeups_affine);
+ }
- if (!balanced)
- return 0;
-
- schedstat_inc(sd->ttwu_move_affine);
- schedstat_inc(p->se.statistics.nr_wakeups_affine);
-
- return 1;
+ return affine;
}
static inline int task_util(struct task_struct *p);
@@ -5459,12 +5405,12 @@ find_idlest_group(struct sched_domain *sd, struct task_struct *p,
int i;
/* Skip over this group if it has no CPUs allowed */
- if (!cpumask_intersects(sched_group_cpus(group),
+ if (!cpumask_intersects(sched_group_span(group),
&p->cpus_allowed))
continue;
local_group = cpumask_test_cpu(this_cpu,
- sched_group_cpus(group));
+ sched_group_span(group));
/*
* Tally up the load of all CPUs in the group and find
@@ -5474,7 +5420,7 @@ find_idlest_group(struct sched_domain *sd, struct task_struct *p,
runnable_load = 0;
max_spare_cap = 0;
- for_each_cpu(i, sched_group_cpus(group)) {
+ for_each_cpu(i, sched_group_span(group)) {
/* Bias balancing toward cpus of our domain */
if (local_group)
load = source_load(i, load_idx);
@@ -5577,10 +5523,10 @@ find_idlest_cpu(struct sched_group *group, struct task_struct *p, int this_cpu)
/* Check if we have any choice: */
if (group->group_weight == 1)
- return cpumask_first(sched_group_cpus(group));
+ return cpumask_first(sched_group_span(group));
/* Traverse only the allowed CPUs */
- for_each_cpu_and(i, sched_group_cpus(group), &p->cpus_allowed) {
+ for_each_cpu_and(i, sched_group_span(group), &p->cpus_allowed) {
if (idle_cpu(i)) {
struct rq *rq = cpu_rq(i);
struct cpuidle_state *idle = idle_get_state(rq);
@@ -5615,43 +5561,6 @@ find_idlest_cpu(struct sched_group *group, struct task_struct *p, int this_cpu)
return shallowest_idle_cpu != -1 ? shallowest_idle_cpu : least_loaded_cpu;
}
-/*
- * Implement a for_each_cpu() variant that starts the scan at a given cpu
- * (@start), and wraps around.
- *
- * This is used to scan for idle CPUs; such that not all CPUs looking for an
- * idle CPU find the same CPU. The down-side is that tasks tend to cycle
- * through the LLC domain.
- *
- * Especially tbench is found sensitive to this.
- */
-
-static int cpumask_next_wrap(int n, const struct cpumask *mask, int start, int *wrapped)
-{
- int next;
-
-again:
- next = find_next_bit(cpumask_bits(mask), nr_cpumask_bits, n+1);
-
- if (*wrapped) {
- if (next >= start)
- return nr_cpumask_bits;
- } else {
- if (next >= nr_cpumask_bits) {
- *wrapped = 1;
- n = -1;
- goto again;
- }
- }
-
- return next;
-}
-
-#define for_each_cpu_wrap(cpu, mask, start, wrap) \
- for ((wrap) = 0, (cpu) = (start)-1; \
- (cpu) = cpumask_next_wrap((cpu), (mask), (start), &(wrap)), \
- (cpu) < nr_cpumask_bits; )
-
#ifdef CONFIG_SCHED_SMT
static inline void set_idle_cores(int cpu, int val)
@@ -5711,7 +5620,7 @@ unlock:
static int select_idle_core(struct task_struct *p, struct sched_domain *sd, int target)
{
struct cpumask *cpus = this_cpu_cpumask_var_ptr(select_idle_mask);
- int core, cpu, wrap;
+ int core, cpu;
if (!static_branch_likely(&sched_smt_present))
return -1;
@@ -5721,7 +5630,7 @@ static int select_idle_core(struct task_struct *p, struct sched_domain *sd, int
cpumask_and(cpus, sched_domain_span(sd), &p->cpus_allowed);
- for_each_cpu_wrap(core, cpus, target, wrap) {
+ for_each_cpu_wrap(core, cpus, target) {
bool idle = true;
for_each_cpu(cpu, cpu_smt_mask(core)) {
@@ -5784,27 +5693,38 @@ static inline int select_idle_smt(struct task_struct *p, struct sched_domain *sd
static int select_idle_cpu(struct task_struct *p, struct sched_domain *sd, int target)
{
struct sched_domain *this_sd;
- u64 avg_cost, avg_idle = this_rq()->avg_idle;
+ u64 avg_cost, avg_idle;
u64 time, cost;
s64 delta;
- int cpu, wrap;
+ int cpu, nr = INT_MAX;
this_sd = rcu_dereference(*this_cpu_ptr(&sd_llc));
if (!this_sd)
return -1;
- avg_cost = this_sd->avg_scan_cost;
-
/*
* Due to large variance we need a large fuzz factor; hackbench in
* particularly is sensitive here.
*/
- if (sched_feat(SIS_AVG_CPU) && (avg_idle / 512) < avg_cost)
+ avg_idle = this_rq()->avg_idle / 512;
+ avg_cost = this_sd->avg_scan_cost + 1;
+
+ if (sched_feat(SIS_AVG_CPU) && avg_idle < avg_cost)
return -1;
+ if (sched_feat(SIS_PROP)) {
+ u64 span_avg = sd->span_weight * avg_idle;
+ if (span_avg > 4*avg_cost)
+ nr = div_u64(span_avg, avg_cost);
+ else
+ nr = 4;
+ }
+
time = local_clock();
- for_each_cpu_wrap(cpu, sched_domain_span(sd), target, wrap) {
+ for_each_cpu_wrap(cpu, sched_domain_span(sd), target) {
+ if (!--nr)
+ return -1;
if (!cpumask_test_cpu(cpu, &p->cpus_allowed))
continue;
if (idle_cpu(cpu))
@@ -5986,11 +5906,15 @@ select_task_rq_fair(struct task_struct *p, int prev_cpu, int sd_flag, int wake_f
if (affine_sd) {
sd = NULL; /* Prefer wake_affine over balance flags */
- if (cpu != prev_cpu && wake_affine(affine_sd, p, prev_cpu, sync))
+ if (cpu == prev_cpu)
+ goto pick_cpu;
+
+ if (wake_affine(affine_sd, p, prev_cpu, sync))
new_cpu = cpu;
}
if (!sd) {
+ pick_cpu:
if (sd_flag & SD_BALANCE_WAKE) /* XXX always ? */
new_cpu = select_idle_sibling(p, prev_cpu, new_cpu);
@@ -6143,8 +6067,11 @@ static void set_last_buddy(struct sched_entity *se)
if (entity_is_task(se) && unlikely(task_of(se)->policy == SCHED_IDLE))
return;
- for_each_sched_entity(se)
+ for_each_sched_entity(se) {
+ if (SCHED_WARN_ON(!se->on_rq))
+ return;
cfs_rq_of(se)->last = se;
+ }
}
static void set_next_buddy(struct sched_entity *se)
@@ -6152,8 +6079,11 @@ static void set_next_buddy(struct sched_entity *se)
if (entity_is_task(se) && unlikely(task_of(se)->policy == SCHED_IDLE))
return;
- for_each_sched_entity(se)
+ for_each_sched_entity(se) {
+ if (SCHED_WARN_ON(!se->on_rq))
+ return;
cfs_rq_of(se)->next = se;
+ }
}
static void set_skip_buddy(struct sched_entity *se)
@@ -6661,6 +6591,10 @@ static int migrate_degrades_locality(struct task_struct *p, struct lb_env *env)
if (dst_nid == p->numa_preferred_nid)
return 0;
+ /* Leaving a core idle is often worse than degrading locality. */
+ if (env->idle != CPU_NOT_IDLE)
+ return -1;
+
if (numa_group) {
src_faults = group_faults(p, src_nid);
dst_faults = group_faults(p, dst_nid);
@@ -6769,7 +6703,7 @@ static void detach_task(struct task_struct *p, struct lb_env *env)
lockdep_assert_held(&env->src_rq->lock);
p->on_rq = TASK_ON_RQ_MIGRATING;
- deactivate_task(env->src_rq, p, 0);
+ deactivate_task(env->src_rq, p, DEQUEUE_NOCLOCK);
set_task_cpu(p, env->dst_cpu);
}
@@ -6902,7 +6836,7 @@ static void attach_task(struct rq *rq, struct task_struct *p)
lockdep_assert_held(&rq->lock);
BUG_ON(task_rq(p) != rq);
- activate_task(rq, p, 0);
+ activate_task(rq, p, ENQUEUE_NOCLOCK);
p->on_rq = TASK_ON_RQ_QUEUED;
check_preempt_curr(rq, p, 0);
}
@@ -6913,9 +6847,12 @@ static void attach_task(struct rq *rq, struct task_struct *p)
*/
static void attach_one_task(struct rq *rq, struct task_struct *p)
{
- raw_spin_lock(&rq->lock);
+ struct rq_flags rf;
+
+ rq_lock(rq, &rf);
+ update_rq_clock(rq);
attach_task(rq, p);
- raw_spin_unlock(&rq->lock);
+ rq_unlock(rq, &rf);
}
/*
@@ -6926,8 +6863,10 @@ static void attach_tasks(struct lb_env *env)
{
struct list_head *tasks = &env->tasks;
struct task_struct *p;
+ struct rq_flags rf;
- raw_spin_lock(&env->dst_rq->lock);
+ rq_lock(env->dst_rq, &rf);
+ update_rq_clock(env->dst_rq);
while (!list_empty(tasks)) {
p = list_first_entry(tasks, struct task_struct, se.group_node);
@@ -6936,24 +6875,44 @@ static void attach_tasks(struct lb_env *env)
attach_task(env->dst_rq, p);
}
- raw_spin_unlock(&env->dst_rq->lock);
+ rq_unlock(env->dst_rq, &rf);
}
#ifdef CONFIG_FAIR_GROUP_SCHED
+
+static inline bool cfs_rq_is_decayed(struct cfs_rq *cfs_rq)
+{
+ if (cfs_rq->load.weight)
+ return false;
+
+ if (cfs_rq->avg.load_sum)
+ return false;
+
+ if (cfs_rq->avg.util_sum)
+ return false;
+
+ if (cfs_rq->runnable_load_sum)
+ return false;
+
+ return true;
+}
+
static void update_blocked_averages(int cpu)
{
struct rq *rq = cpu_rq(cpu);
- struct cfs_rq *cfs_rq;
- unsigned long flags;
+ struct cfs_rq *cfs_rq, *pos;
+ struct rq_flags rf;
- raw_spin_lock_irqsave(&rq->lock, flags);
+ rq_lock_irqsave(rq, &rf);
update_rq_clock(rq);
/*
* Iterates the task_group tree in a bottom up fashion, see
* list_add_leaf_cfs_rq() for details.
*/
- for_each_leaf_cfs_rq(rq, cfs_rq) {
+ for_each_leaf_cfs_rq_safe(rq, cfs_rq, pos) {
+ struct sched_entity *se;
+
/* throttled entities do not contribute to load */
if (throttled_hierarchy(cfs_rq))
continue;
@@ -6961,11 +6920,19 @@ static void update_blocked_averages(int cpu)
if (update_cfs_rq_load_avg(cfs_rq_clock_task(cfs_rq), cfs_rq, true))
update_tg_load_avg(cfs_rq, 0);
- /* Propagate pending load changes to the parent */
- if (cfs_rq->tg->se[cpu])
- update_load_avg(cfs_rq->tg->se[cpu], 0);
+ /* Propagate pending load changes to the parent, if any: */
+ se = cfs_rq->tg->se[cpu];
+ if (se && !skip_blocked_update(se))
+ update_load_avg(se, 0);
+
+ /*
+ * There can be a lot of idle CPU cgroups. Don't let fully
+ * decayed cfs_rqs linger on the list.
+ */
+ if (cfs_rq_is_decayed(cfs_rq))
+ list_del_leaf_cfs_rq(cfs_rq);
}
- raw_spin_unlock_irqrestore(&rq->lock, flags);
+ rq_unlock_irqrestore(rq, &rf);
}
/*
@@ -7019,12 +6986,12 @@ static inline void update_blocked_averages(int cpu)
{
struct rq *rq = cpu_rq(cpu);
struct cfs_rq *cfs_rq = &rq->cfs;
- unsigned long flags;
+ struct rq_flags rf;
- raw_spin_lock_irqsave(&rq->lock, flags);
+ rq_lock_irqsave(rq, &rf);
update_rq_clock(rq);
update_cfs_rq_load_avg(cfs_rq_clock_task(cfs_rq), cfs_rq, true);
- raw_spin_unlock_irqrestore(&rq->lock, flags);
+ rq_unlock_irqrestore(rq, &rf);
}
static unsigned long task_h_load(struct task_struct *p)
@@ -7196,7 +7163,7 @@ void update_group_capacity(struct sched_domain *sd, int cpu)
* span the current group.
*/
- for_each_cpu(cpu, sched_group_cpus(sdg)) {
+ for_each_cpu(cpu, sched_group_span(sdg)) {
struct sched_group_capacity *sgc;
struct rq *rq = cpu_rq(cpu);
@@ -7375,7 +7342,7 @@ static inline void update_sg_lb_stats(struct lb_env *env,
memset(sgs, 0, sizeof(*sgs));
- for_each_cpu_and(i, sched_group_cpus(group), env->cpus) {
+ for_each_cpu_and(i, sched_group_span(group), env->cpus) {
struct rq *rq = cpu_rq(i);
/* Bias balancing toward cpus of our domain */
@@ -7525,6 +7492,7 @@ static inline void update_sd_lb_stats(struct lb_env *env, struct sd_lb_stats *sd
{
struct sched_domain *child = env->sd->child;
struct sched_group *sg = env->sd->groups;
+ struct sg_lb_stats *local = &sds->local_stat;
struct sg_lb_stats tmp_sgs;
int load_idx, prefer_sibling = 0;
bool overload = false;
@@ -7538,10 +7506,10 @@ static inline void update_sd_lb_stats(struct lb_env *env, struct sd_lb_stats *sd
struct sg_lb_stats *sgs = &tmp_sgs;
int local_group;
- local_group = cpumask_test_cpu(env->dst_cpu, sched_group_cpus(sg));
+ local_group = cpumask_test_cpu(env->dst_cpu, sched_group_span(sg));
if (local_group) {
sds->local = sg;
- sgs = &sds->local_stat;
+ sgs = local;
if (env->idle != CPU_NEWLY_IDLE ||
time_after_eq(jiffies, sg->sgc->next_update))
@@ -7565,8 +7533,8 @@ static inline void update_sd_lb_stats(struct lb_env *env, struct sd_lb_stats *sd
* the tasks on the system).
*/
if (prefer_sibling && sds->local &&
- group_has_capacity(env, &sds->local_stat) &&
- (sgs->sum_nr_running > 1)) {
+ group_has_capacity(env, local) &&
+ (sgs->sum_nr_running > local->sum_nr_running + 1)) {
sgs->group_no_capacity = 1;
sgs->group_type = group_classify(sg, sgs);
}
@@ -7597,7 +7565,7 @@ next_group:
/**
* check_asym_packing - Check to see if the group is packed into the
- * sched doman.
+ * sched domain.
*
* This is primarily intended to used at the sibling level. Some
* cores like POWER7 prefer to use lower numbered SMT threads. In the
@@ -7893,7 +7861,7 @@ static struct rq *find_busiest_queue(struct lb_env *env,
unsigned long busiest_load = 0, busiest_capacity = 1;
int i;
- for_each_cpu_and(i, sched_group_cpus(group), env->cpus) {
+ for_each_cpu_and(i, sched_group_span(group), env->cpus) {
unsigned long capacity, wl;
enum fbq_type rt;
@@ -7999,7 +7967,6 @@ static int active_load_balance_cpu_stop(void *data);
static int should_we_balance(struct lb_env *env)
{
struct sched_group *sg = env->sd->groups;
- struct cpumask *sg_cpus, *sg_mask;
int cpu, balance_cpu = -1;
/*
@@ -8009,11 +7976,9 @@ static int should_we_balance(struct lb_env *env)
if (env->idle == CPU_NEWLY_IDLE)
return 1;
- sg_cpus = sched_group_cpus(sg);
- sg_mask = sched_group_mask(sg);
/* Try to find first idle cpu */
- for_each_cpu_and(cpu, sg_cpus, env->cpus) {
- if (!cpumask_test_cpu(cpu, sg_mask) || !idle_cpu(cpu))
+ for_each_cpu_and(cpu, group_balance_mask(sg), env->cpus) {
+ if (!idle_cpu(cpu))
continue;
balance_cpu = cpu;
@@ -8042,14 +8007,14 @@ static int load_balance(int this_cpu, struct rq *this_rq,
struct sched_domain *sd_parent = sd->parent;
struct sched_group *group;
struct rq *busiest;
- unsigned long flags;
+ struct rq_flags rf;
struct cpumask *cpus = this_cpu_cpumask_var_ptr(load_balance_mask);
struct lb_env env = {
.sd = sd,
.dst_cpu = this_cpu,
.dst_rq = this_rq,
- .dst_grpmask = sched_group_cpus(sd->groups),
+ .dst_grpmask = sched_group_span(sd->groups),
.idle = idle,
.loop_break = sched_nr_migrate_break,
.cpus = cpus,
@@ -8105,7 +8070,7 @@ redo:
env.loop_max = min(sysctl_sched_nr_migrate, busiest->nr_running);
more_balance:
- raw_spin_lock_irqsave(&busiest->lock, flags);
+ rq_lock_irqsave(busiest, &rf);
update_rq_clock(busiest);
/*
@@ -8122,14 +8087,14 @@ more_balance:
* See task_rq_lock() family for the details.
*/
- raw_spin_unlock(&busiest->lock);
+ rq_unlock(busiest, &rf);
if (cur_ld_moved) {
attach_tasks(&env);
ld_moved += cur_ld_moved;
}
- local_irq_restore(flags);
+ local_irq_restore(rf.flags);
if (env.flags & LBF_NEED_BREAK) {
env.flags &= ~LBF_NEED_BREAK;
@@ -8207,6 +8172,8 @@ more_balance:
sd->nr_balance_failed++;
if (need_active_balance(&env)) {
+ unsigned long flags;
+
raw_spin_lock_irqsave(&busiest->lock, flags);
/* don't kick the active_load_balance_cpu_stop,
@@ -8444,8 +8411,9 @@ static int active_load_balance_cpu_stop(void *data)
struct rq *target_rq = cpu_rq(target_cpu);
struct sched_domain *sd;
struct task_struct *p = NULL;
+ struct rq_flags rf;
- raw_spin_lock_irq(&busiest_rq->lock);
+ rq_lock_irq(busiest_rq, &rf);
/* make sure the requested cpu hasn't gone down in the meantime */
if (unlikely(busiest_cpu != smp_processor_id() ||
@@ -8496,7 +8464,7 @@ static int active_load_balance_cpu_stop(void *data)
rcu_read_unlock();
out_unlock:
busiest_rq->active_balance = 0;
- raw_spin_unlock(&busiest_rq->lock);
+ rq_unlock(busiest_rq, &rf);
if (p)
attach_one_task(target_rq, p);
@@ -8622,6 +8590,10 @@ void nohz_balance_enter_idle(int cpu)
if (!cpu_active(cpu))
return;
+ /* Spare idle load balancing on CPUs that don't want to be disturbed: */
+ if (!is_housekeeping_cpu(cpu))
+ return;
+
if (test_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu)))
return;
@@ -8794,10 +8766,13 @@ static void nohz_idle_balance(struct rq *this_rq, enum cpu_idle_type idle)
* do the balance.
*/
if (time_after_eq(jiffies, rq->next_balance)) {
- raw_spin_lock_irq(&rq->lock);
+ struct rq_flags rf;
+
+ rq_lock_irq(rq, &rf);
update_rq_clock(rq);
cpu_load_update_idle(rq);
- raw_spin_unlock_irq(&rq->lock);
+ rq_unlock_irq(rq, &rf);
+
rebalance_domains(rq, CPU_IDLE);
}
@@ -8988,8 +8963,9 @@ static void task_fork_fair(struct task_struct *p)
struct cfs_rq *cfs_rq;
struct sched_entity *se = &p->se, *curr;
struct rq *rq = this_rq();
+ struct rq_flags rf;
- raw_spin_lock(&rq->lock);
+ rq_lock(rq, &rf);
update_rq_clock(rq);
cfs_rq = task_cfs_rq(current);
@@ -9010,7 +8986,7 @@ static void task_fork_fair(struct task_struct *p)
}
se->vruntime -= cfs_rq->min_vruntime;
- raw_spin_unlock(&rq->lock);
+ rq_unlock(rq, &rf);
}
/*
@@ -9372,7 +9348,6 @@ static DEFINE_MUTEX(shares_mutex);
int sched_group_set_shares(struct task_group *tg, unsigned long shares)
{
int i;
- unsigned long flags;
/*
* We can't change the weight of the root cgroup.
@@ -9389,19 +9364,17 @@ int sched_group_set_shares(struct task_group *tg, unsigned long shares)
tg->shares = shares;
for_each_possible_cpu(i) {
struct rq *rq = cpu_rq(i);
- struct sched_entity *se;
+ struct sched_entity *se = tg->se[i];
+ struct rq_flags rf;
- se = tg->se[i];
/* Propagate contribution to hierarchy */
- raw_spin_lock_irqsave(&rq->lock, flags);
-
- /* Possible calls to update_curr() need rq clock */
+ rq_lock_irqsave(rq, &rf);
update_rq_clock(rq);
for_each_sched_entity(se) {
update_load_avg(se, UPDATE_TG);
update_cfs_shares(se);
}
- raw_spin_unlock_irqrestore(&rq->lock, flags);
+ rq_unlock_irqrestore(rq, &rf);
}
done:
@@ -9485,10 +9458,10 @@ const struct sched_class fair_sched_class = {
#ifdef CONFIG_SCHED_DEBUG
void print_cfs_stats(struct seq_file *m, int cpu)
{
- struct cfs_rq *cfs_rq;
+ struct cfs_rq *cfs_rq, *pos;
rcu_read_lock();
- for_each_leaf_cfs_rq(cpu_rq(cpu), cfs_rq)
+ for_each_leaf_cfs_rq_safe(cpu_rq(cpu), cfs_rq, pos)
print_cfs_rq(m, cpu, cfs_rq);
rcu_read_unlock();
}