Commit 2475bf02 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'sched_urgent_for_v6.2_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull scheduler fixes from Borislav Petkov:

 - Make sure the scheduler doesn't use stale frequency scaling values
   when latter get disabled due to a value error

 - Fix a NULL pointer access on UP configs

 - Use the proper locking when updating CPU capacity

* tag 'sched_urgent_for_v6.2_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/aperfmperf: Erase stale arch_freq_scale values when disabling frequency invariance readings
  sched/core: Fix NULL pointer access fault in sched_setaffinity() with non-SMP configs
  sched/fair: Fixes for capacity inversion detection
  sched/uclamp: Fix a uninitialized variable warnings
parents ab2f4087 5f5cc9ed

arch/x86/kernel/cpu/aperfmperf.c

+9 −0
Original line number Diff line number Diff line
@@ -330,7 +330,16 @@ static void __init bp_init_freq_invariance(void) 


static void disable_freq_invariance_workfn(struct work_struct *work)

{

	int cpu;



	static_branch_disable(&arch_scale_freq_key);



	/*

	 * Set arch_freq_scale to a default value on all cpus

	 * This negates the effect of scaling

	 */

	for_each_possible_cpu(cpu)

		per_cpu(arch_freq_scale, cpu) = SCHED_CAPACITY_SCALE;

}



static DECLARE_WORK(disable_freq_invariance_work,

kernel/sched/core.c

+8 −2
Original line number Diff line number Diff line
@@ -8290,12 +8290,18 @@ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask) 
	if (retval)

		goto out_put_task;



	/*

	 * With non-SMP configs, user_cpus_ptr/user_mask isn't used and

	 * alloc_user_cpus_ptr() returns NULL.

	 */

	user_mask = alloc_user_cpus_ptr(NUMA_NO_NODE);

	if (IS_ENABLED(CONFIG_SMP) && !user_mask) {

	if (user_mask) {

		cpumask_copy(user_mask, in_mask);

	} else if (IS_ENABLED(CONFIG_SMP)) {

		retval = -ENOMEM;

		goto out_put_task;

	}

	cpumask_copy(user_mask, in_mask);



	ac = (struct affinity_context){

		.new_mask  = in_mask,

		.user_mask = user_mask,

kernel/sched/fair.c

+27 −21
Original line number Diff line number Diff line
@@ -7229,10 +7229,10 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu) 
	eenv_task_busy_time(&eenv, p, prev_cpu);



	for (; pd; pd = pd->next) {

		unsigned long util_min = p_util_min, util_max = p_util_max;

		unsigned long cpu_cap, cpu_thermal_cap, util;

		unsigned long cur_delta, max_spare_cap = 0;

		unsigned long rq_util_min, rq_util_max;

		unsigned long util_min, util_max;

		unsigned long prev_spare_cap = 0;

		int max_spare_cap_cpu = -1;

		unsigned long base_energy;
@@ -7251,6 +7251,8 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu) 
		eenv.pd_cap = 0;



		for_each_cpu(cpu, cpus) {

			struct rq *rq = cpu_rq(cpu);



			eenv.pd_cap += cpu_thermal_cap;



			if (!cpumask_test_cpu(cpu, sched_domain_span(sd)))
@@ -7269,11 +7271,7 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu) 
			 * much capacity we can get out of the CPU; this is

			 * aligned with sched_cpu_util().

			 */

			if (uclamp_is_used()) {

				if (uclamp_rq_is_idle(cpu_rq(cpu))) {

					util_min = p_util_min;

					util_max = p_util_max;

				} else {

			if (uclamp_is_used() && !uclamp_rq_is_idle(rq)) {

				/*

				 * Open code uclamp_rq_util_with() except for

				 * the clamp() part. Ie: apply max aggregation
@@ -7281,13 +7279,12 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu) 
				 * operate on non clamped util but must use the

				 * max-aggregated uclamp_{min, max}.

				 */

					rq_util_min = uclamp_rq_get(cpu_rq(cpu), UCLAMP_MIN);

					rq_util_max = uclamp_rq_get(cpu_rq(cpu), UCLAMP_MAX);

				rq_util_min = uclamp_rq_get(rq, UCLAMP_MIN);

				rq_util_max = uclamp_rq_get(rq, UCLAMP_MAX);



				util_min = max(rq_util_min, p_util_min);

				util_max = max(rq_util_max, p_util_max);

			}

			}

			if (!util_fits_cpu(util, util_min, util_max, cpu))

				continue;
@@ -8871,16 +8868,23 @@ static void update_cpu_capacity(struct sched_domain *sd, int cpu) 
	 *   * Thermal pressure will impact all cpus in this perf domain

	 *     equally.

	 */

	if (static_branch_unlikely(&sched_asym_cpucapacity)) {

	if (sched_energy_enabled()) {

		unsigned long inv_cap = capacity_orig - thermal_load_avg(rq);

		struct perf_domain *pd = rcu_dereference(rq->rd->pd);

		struct perf_domain *pd;



		rcu_read_lock();



		pd = rcu_dereference(rq->rd->pd);

		rq->cpu_capacity_inverted = 0;



		for (; pd; pd = pd->next) {

			struct cpumask *pd_span = perf_domain_span(pd);

			unsigned long pd_cap_orig, pd_cap;



			/* We can't be inverted against our own pd */

			if (cpumask_test_cpu(cpu_of(rq), pd_span))

				continue;



			cpu = cpumask_any(pd_span);

			pd_cap_orig = arch_scale_cpu_capacity(cpu);
@@ -8905,6 +8909,8 @@ static void update_cpu_capacity(struct sched_domain *sd, int cpu) 
				break;

			}

		}



		rcu_read_unlock();

	}



	trace_sched_cpu_capacity_tp(rq);