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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-09-27 10:34:19 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-09-27 10:34:19 -0300
commit1c29f4306f557ef5d9ed515ec8881f4d1735b058 (patch)
tree1359b9f8403af67e35bbbaae36e2b60c9bb3d2da /kernel/sched
parent5b465b045af3a649a89b8a5c5bfdece20ffc0345 (diff)
Linux-libre 4.7.5-gnupck-4.7.5-gnu
Diffstat (limited to 'kernel/sched')
-rw-r--r--kernel/sched/bfs.c58
-rw-r--r--kernel/sched/bfs_sched.h13
-rw-r--r--kernel/sched/core.c22
3 files changed, 33 insertions, 60 deletions
diff --git a/kernel/sched/bfs.c b/kernel/sched/bfs.c
index 60b9ab785..67f93e752 100644
--- a/kernel/sched/bfs.c
+++ b/kernel/sched/bfs.c
@@ -35,7 +35,7 @@
#include <linux/init.h>
#include <asm/uaccess.h>
#include <linux/highmem.h>
-#include <asm/mmu_context.h>
+#include <linux/mmu_context.h>
#include <linux/interrupt.h>
#include <linux/capability.h>
#include <linux/completion.h>
@@ -137,7 +137,7 @@
void print_scheduler_version(void)
{
- printk(KERN_INFO "BFS CPU scheduler v0.497 by Con Kolivas.\n");
+ printk(KERN_INFO "BFS CPU scheduler v0.502 by Con Kolivas.\n");
}
/*
@@ -676,6 +676,11 @@ static inline int queued_notrunning(void)
return grq.qnr;
}
+static unsigned long rq_load_avg(struct rq *rq)
+{
+ return rq->soft_affined * SCHED_CAPACITY_SCALE;
+}
+
#ifdef CONFIG_SMT_NICE
static const cpumask_t *thread_cpumask(int cpu);
@@ -748,41 +753,9 @@ static bool smt_should_schedule(struct task_struct *p, struct rq *this_rq)
/* Sorry, you lose */
return false;
}
-
-static unsigned long cpu_load_avg(struct rq *rq)
-{
- return rq->soft_affined * SCHED_CAPACITY_SCALE;
-}
-
-/*
- * This is the proportion of SCHED_CAPACITY_SCALE (1024) used when each thread
- * of a CPU with SMT siblings is in use.
- */
-#define SCHED_SMT_LOAD (890)
-
-/*
- * Load of a CPU with smt siblings should be considered to be the load from all
- * the SMT siblings, thus will be >1 if both threads are in use since they are
- * not full cores.
- */
-static unsigned long smt_load_avg(struct rq *rq)
-{
- unsigned long load = rq->soft_affined * SCHED_SMT_LOAD;
- int cpu;
-
- for_each_cpu(cpu, thread_cpumask(rq->cpu))
- load += cpu_rq(cpu)->soft_affined * SCHED_SMT_LOAD;
- return load;
-}
-
-static unsigned long (*rq_load_avg)(struct rq *rq) = &cpu_load_avg;
-#else
+#else /* CONFIG_SMT_NICE */
#define smt_schedule(p, this_rq) (true)
-static inline unsigned long rq_load_avg(struct rq *rq)
-{
- return rq->soft_affined * SCHED_CAPACITY_SCALE;
-}
-#endif
+#endif /* CONFIG_SMT_NICE */
#ifdef CONFIG_SMP
/*
* The cpu_idle_map stores a bitmap of all the CPUs currently idle to
@@ -1055,21 +1028,13 @@ void set_task_cpu(struct task_struct *p, unsigned int cpu)
*/
smp_wmb();
if (p->on_rq) {
- struct rq *rq;
+ struct rq *rq = task_rq(p);
- /*
- * set_task_cpu can be set on other CPUs so call cpufreq_trigger
- * explicitly telling it what CPU is being updated as the value
- * of soft_affined has changed.
- */
- rq = task_rq(p);
rq->soft_affined--;
update_load_avg(rq);
- other_cpufreq_trigger(tcpu, grq.niffies, rq->load_avg);
rq = cpu_rq(cpu);
rq->soft_affined++;
update_load_avg(rq);
- other_cpufreq_trigger(cpu, grq.niffies, rq->load_avg);
}
task_thread_info(p)->cpu = cpu;
}
@@ -7084,7 +7049,7 @@ void __init sched_init_smp(void)
/* First check if this cpu is in the same node */
for_each_domain(cpu, sd) {
- if (sd->level > SD_LV_NODE)
+ if (sd->level > SD_LV_MC)
continue;
/* Set locality to local node if not already found lower */
for_each_cpu(other_cpu, sched_domain_span(sd)) {
@@ -7124,7 +7089,6 @@ void __init sched_init_smp(void)
check_siblings = &check_smt_siblings;
wake_siblings = &wake_smt_siblings;
smt_schedule = &smt_should_schedule;
- rq_load_avg = &smt_load_avg;
}
#endif
grq_unlock_irq();
diff --git a/kernel/sched/bfs_sched.h b/kernel/sched/bfs_sched.h
index d4a8be9be..e7fe1d0a5 100644
--- a/kernel/sched/bfs_sched.h
+++ b/kernel/sched/bfs_sched.h
@@ -207,23 +207,10 @@ static inline void cpufreq_trigger(u64 time, unsigned long util)
if (data)
data->func(data, time, util, SCHED_CAPACITY_SCALE);
}
-
-static inline void other_cpufreq_trigger(int cpu, u64 time, unsigned long util)
-{
- struct update_util_data *data;
-
- data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data, cpu));
- if (data)
- data->func(data, time, util, SCHED_CAPACITY_SCALE);
-}
#else
static inline void cpufreq_trigger(u64 time, unsigned long util)
{
}
-
-static inline void other_cpufreq_trigger(int cpu, u64 time, unsigned long util)
-{
-}
#endif /* CONFIG_CPU_FREQ */
#ifdef arch_scale_freq_capacity
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 97ee9ac7e..38eacc323 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2015,6 +2015,28 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
success = 1; /* we're going to change ->state */
cpu = task_cpu(p);
+ /*
+ * Ensure we load p->on_rq _after_ p->state, otherwise it would
+ * be possible to, falsely, observe p->on_rq == 0 and get stuck
+ * in smp_cond_load_acquire() below.
+ *
+ * sched_ttwu_pending() try_to_wake_up()
+ * [S] p->on_rq = 1; [L] P->state
+ * UNLOCK rq->lock -----.
+ * \
+ * +--- RMB
+ * schedule() /
+ * LOCK rq->lock -----'
+ * UNLOCK rq->lock
+ *
+ * [task p]
+ * [S] p->state = UNINTERRUPTIBLE [L] p->on_rq
+ *
+ * Pairs with the UNLOCK+LOCK on rq->lock from the
+ * last wakeup of our task and the schedule that got our task
+ * current.
+ */
+ smp_rmb();
if (p->on_rq && ttwu_remote(p, wake_flags))
goto stat;