From 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 27 Apr 2024 12:05:51 +0200 Subject: Adding upstream version 5.10.209. Signed-off-by: Daniel Baumann --- kernel/sched/cpudeadline.c | 296 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 296 insertions(+) create mode 100644 kernel/sched/cpudeadline.c (limited to 'kernel/sched/cpudeadline.c') diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c new file mode 100644 index 000000000..8cb06c8c7 --- /dev/null +++ b/kernel/sched/cpudeadline.c @@ -0,0 +1,296 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * kernel/sched/cpudl.c + * + * Global CPU deadline management + * + * Author: Juri Lelli + */ +#include "sched.h" + +static inline int parent(int i) +{ + return (i - 1) >> 1; +} + +static inline int left_child(int i) +{ + return (i << 1) + 1; +} + +static inline int right_child(int i) +{ + return (i << 1) + 2; +} + +static void cpudl_heapify_down(struct cpudl *cp, int idx) +{ + int l, r, largest; + + int orig_cpu = cp->elements[idx].cpu; + u64 orig_dl = cp->elements[idx].dl; + + if (left_child(idx) >= cp->size) + return; + + /* adapted from lib/prio_heap.c */ + while (1) { + u64 largest_dl; + + l = left_child(idx); + r = right_child(idx); + largest = idx; + largest_dl = orig_dl; + + if ((l < cp->size) && dl_time_before(orig_dl, + cp->elements[l].dl)) { + largest = l; + largest_dl = cp->elements[l].dl; + } + if ((r < cp->size) && dl_time_before(largest_dl, + cp->elements[r].dl)) + largest = r; + + if (largest == idx) + break; + + /* pull largest child onto idx */ + cp->elements[idx].cpu = cp->elements[largest].cpu; + cp->elements[idx].dl = cp->elements[largest].dl; + cp->elements[cp->elements[idx].cpu].idx = idx; + idx = largest; + } + /* actual push down of saved original values orig_* */ + cp->elements[idx].cpu = orig_cpu; + cp->elements[idx].dl = orig_dl; + cp->elements[cp->elements[idx].cpu].idx = idx; +} + +static void cpudl_heapify_up(struct cpudl *cp, int idx) +{ + int p; + + int orig_cpu = cp->elements[idx].cpu; + u64 orig_dl = cp->elements[idx].dl; + + if (idx == 0) + return; + + do { + p = parent(idx); + if (dl_time_before(orig_dl, cp->elements[p].dl)) + break; + /* pull parent onto idx */ + cp->elements[idx].cpu = cp->elements[p].cpu; + cp->elements[idx].dl = cp->elements[p].dl; + cp->elements[cp->elements[idx].cpu].idx = idx; + idx = p; + } while (idx != 0); + /* actual push up of saved original values orig_* */ + cp->elements[idx].cpu = orig_cpu; + cp->elements[idx].dl = orig_dl; + cp->elements[cp->elements[idx].cpu].idx = idx; +} + +static void cpudl_heapify(struct cpudl *cp, int idx) +{ + if (idx > 0 && dl_time_before(cp->elements[parent(idx)].dl, + cp->elements[idx].dl)) + cpudl_heapify_up(cp, idx); + else + cpudl_heapify_down(cp, idx); +} + +static inline int cpudl_maximum(struct cpudl *cp) +{ + return cp->elements[0].cpu; +} + +/* + * cpudl_find - find the best (later-dl) CPU in the system + * @cp: the cpudl max-heap context + * @p: the task + * @later_mask: a mask to fill in with the selected CPUs (or NULL) + * + * Returns: int - CPUs were found + */ +int cpudl_find(struct cpudl *cp, struct task_struct *p, + struct cpumask *later_mask) +{ + const struct sched_dl_entity *dl_se = &p->dl; + + if (later_mask && + cpumask_and(later_mask, cp->free_cpus, p->cpus_ptr)) { + unsigned long cap, max_cap = 0; + int cpu, max_cpu = -1; + + if (!static_branch_unlikely(&sched_asym_cpucapacity)) + return 1; + + /* Ensure the capacity of the CPUs fits the task. */ + for_each_cpu(cpu, later_mask) { + if (!dl_task_fits_capacity(p, cpu)) { + cpumask_clear_cpu(cpu, later_mask); + + cap = capacity_orig_of(cpu); + + if (cap > max_cap || + (cpu == task_cpu(p) && cap == max_cap)) { + max_cap = cap; + max_cpu = cpu; + } + } + } + + if (cpumask_empty(later_mask)) + cpumask_set_cpu(max_cpu, later_mask); + + return 1; + } else { + int best_cpu = cpudl_maximum(cp); + + WARN_ON(best_cpu != -1 && !cpu_present(best_cpu)); + + if (cpumask_test_cpu(best_cpu, p->cpus_ptr) && + dl_time_before(dl_se->deadline, cp->elements[0].dl)) { + if (later_mask) + cpumask_set_cpu(best_cpu, later_mask); + + return 1; + } + } + return 0; +} + +/* + * cpudl_clear - remove a CPU from the cpudl max-heap + * @cp: the cpudl max-heap context + * @cpu: the target CPU + * + * Notes: assumes cpu_rq(cpu)->lock is locked + * + * Returns: (void) + */ +void cpudl_clear(struct cpudl *cp, int cpu) +{ + int old_idx, new_cpu; + unsigned long flags; + + WARN_ON(!cpu_present(cpu)); + + raw_spin_lock_irqsave(&cp->lock, flags); + + old_idx = cp->elements[cpu].idx; + if (old_idx == IDX_INVALID) { + /* + * Nothing to remove if old_idx was invalid. + * This could happen if a rq_offline_dl is + * called for a CPU without -dl tasks running. + */ + } else { + new_cpu = cp->elements[cp->size - 1].cpu; + cp->elements[old_idx].dl = cp->elements[cp->size - 1].dl; + cp->elements[old_idx].cpu = new_cpu; + cp->size--; + cp->elements[new_cpu].idx = old_idx; + cp->elements[cpu].idx = IDX_INVALID; + cpudl_heapify(cp, old_idx); + + cpumask_set_cpu(cpu, cp->free_cpus); + } + raw_spin_unlock_irqrestore(&cp->lock, flags); +} + +/* + * cpudl_set - update the cpudl max-heap + * @cp: the cpudl max-heap context + * @cpu: the target CPU + * @dl: the new earliest deadline for this CPU + * + * Notes: assumes cpu_rq(cpu)->lock is locked + * + * Returns: (void) + */ +void cpudl_set(struct cpudl *cp, int cpu, u64 dl) +{ + int old_idx; + unsigned long flags; + + WARN_ON(!cpu_present(cpu)); + + raw_spin_lock_irqsave(&cp->lock, flags); + + old_idx = cp->elements[cpu].idx; + if (old_idx == IDX_INVALID) { + int new_idx = cp->size++; + + cp->elements[new_idx].dl = dl; + cp->elements[new_idx].cpu = cpu; + cp->elements[cpu].idx = new_idx; + cpudl_heapify_up(cp, new_idx); + cpumask_clear_cpu(cpu, cp->free_cpus); + } else { + cp->elements[old_idx].dl = dl; + cpudl_heapify(cp, old_idx); + } + + raw_spin_unlock_irqrestore(&cp->lock, flags); +} + +/* + * cpudl_set_freecpu - Set the cpudl.free_cpus + * @cp: the cpudl max-heap context + * @cpu: rd attached CPU + */ +void cpudl_set_freecpu(struct cpudl *cp, int cpu) +{ + cpumask_set_cpu(cpu, cp->free_cpus); +} + +/* + * cpudl_clear_freecpu - Clear the cpudl.free_cpus + * @cp: the cpudl max-heap context + * @cpu: rd attached CPU + */ +void cpudl_clear_freecpu(struct cpudl *cp, int cpu) +{ + cpumask_clear_cpu(cpu, cp->free_cpus); +} + +/* + * cpudl_init - initialize the cpudl structure + * @cp: the cpudl max-heap context + */ +int cpudl_init(struct cpudl *cp) +{ + int i; + + raw_spin_lock_init(&cp->lock); + cp->size = 0; + + cp->elements = kcalloc(nr_cpu_ids, + sizeof(struct cpudl_item), + GFP_KERNEL); + if (!cp->elements) + return -ENOMEM; + + if (!zalloc_cpumask_var(&cp->free_cpus, GFP_KERNEL)) { + kfree(cp->elements); + return -ENOMEM; + } + + for_each_possible_cpu(i) + cp->elements[i].idx = IDX_INVALID; + + return 0; +} + +/* + * cpudl_cleanup - clean up the cpudl structure + * @cp: the cpudl max-heap context + */ +void cpudl_cleanup(struct cpudl *cp) +{ + free_cpumask_var(cp->free_cpus); + kfree(cp->elements); +} -- cgit v1.2.3