ANDROID: FIXUP: sched: fix build for non-SMP target
Currently the build for a single-core (e.g. user-mode) Linux is broken
and this configuration is required (at least) to run some network tests.
The main issues for the current code support on single-core systems are:
1. {se,rq}::sched_avg is not available nor maintained for !SMP systems
This means that load and utilisation signals are NOT available in single
core systems. All the EAS code depends on these signals.
2. sched_group_energy is also SMP dependant. Again this means that all the
EAS setup and preparation code (energyn model initialization) has to be
properly guarded/disabled for !SMP systems.
3. SchedFreq depends on utilization signal, which is not available on
!SMP systems.
4. SchedTune is useless on unicore systems if SchedFreq is not available.
5. WALT machinery is not required on single-core systems.
This patch addresses all these issues by enforcing some constraints for
single-core systems:
a) WALT, SchedTune and SchedTune are now dependant on SMP
b) The default governor for !SMP systems is INTERACTIVE
c) The energy model initialisation/build functions are
d) Other minor code re-arrangements and CONFIG_SMP guarding to enable
single core builds.
Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com>
Signed-off-by: Andres Oportus <andresoportus@google.com>
diff --git a/drivers/cpufreq/Kconfig b/drivers/cpufreq/Kconfig
index 96485305..f98a901 100644
--- a/drivers/cpufreq/Kconfig
+++ b/drivers/cpufreq/Kconfig
@@ -194,6 +194,7 @@
config CPU_FREQ_GOV_SCHED
bool "'sched' cpufreq governor"
depends on CPU_FREQ
+ depends on SMP
select CPU_FREQ_GOV_COMMON
help
'sched' - this governor scales cpu frequency from the
diff --git a/include/linux/sched_energy.h b/include/linux/sched_energy.h
index a3f1627..1daf3e1 100644
--- a/include/linux/sched_energy.h
+++ b/include/linux/sched_energy.h
@@ -29,8 +29,16 @@
#define for_each_possible_sd_level(level) \
for (level = 0; level < NR_SD_LEVELS; level++)
+#ifdef CONFIG_SMP
+
extern struct sched_group_energy *sge_array[NR_CPUS][NR_SD_LEVELS];
void init_sched_energy_costs(void);
+#else
+
+#define init_sched_energy_costs() do { } while (0)
+
+#endif /* CONFIG_SMP */
+
#endif
diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h
index 1e5ee70..a8864dc 100644
--- a/include/trace/events/sched.h
+++ b/include/trace/events/sched.h
@@ -611,6 +611,8 @@
__entry->cpu_scale_factor)
);
+#ifdef CONFIG_SMP
+
/*
* Tracepoint for accounting sched averages for tasks.
*/
@@ -910,6 +912,8 @@
__entry->payoff, __entry->region)
);
+#endif /* CONFIG_SMP */
+
#endif /* _TRACE_SCHED_H */
/* This part must be outside protection */
diff --git a/init/Kconfig b/init/Kconfig
index e8c2989..b0bfdde 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1326,6 +1326,7 @@
config SCHED_TUNE
bool "Boosting for CFS tasks (EXPERIMENTAL)"
+ depends on SMP
help
This option enables the system-wide support for task boosting.
When this support is enabled a new sysctl interface is exposed to
diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile
index 86fd8b61..87be483 100644
--- a/kernel/sched/Makefile
+++ b/kernel/sched/Makefile
@@ -16,9 +16,9 @@
endif
obj-y += core.o loadavg.o clock.o cputime.o
-obj-y += idle_task.o fair.o rt.o deadline.o stop_task.o energy.o
+obj-y += idle_task.o fair.o rt.o deadline.o stop_task.o
obj-y += wait.o swait.o completion.o idle.o
-obj-$(CONFIG_SMP) += cpupri.o cpudeadline.o
+obj-$(CONFIG_SMP) += cpupri.o cpudeadline.o energy.o
obj-$(CONFIG_SCHED_AUTOGROUP) += auto_group.o
obj-$(CONFIG_SCHEDSTATS) += stats.o
obj-$(CONFIG_SCHED_DEBUG) += debug.o
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index deff3ca..34b6bf9 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -4534,10 +4534,16 @@
}
#endif
+#ifdef CONFIG_SMP
+static bool cpu_overutilized(int cpu);
static unsigned long capacity_orig_of(int cpu);
static unsigned long cpu_util(int cpu);
static inline unsigned long boosted_cpu_util(int cpu);
+#else
+#define boosted_cpu_util(cpu) cpu_util(cpu)
+#endif
+#ifdef CONFIG_SMP
static void update_capacity_of(int cpu)
{
unsigned long req_cap;
@@ -4550,8 +4556,7 @@
req_cap = req_cap * SCHED_CAPACITY_SCALE / capacity_orig_of(cpu);
set_cfs_cpu_capacity(cpu, true, req_cap);
}
-
-static bool cpu_overutilized(int cpu);
+#endif
/*
* The enqueue_task method is called before nr_running is
@@ -4563,8 +4568,10 @@
{
struct cfs_rq *cfs_rq;
struct sched_entity *se = &p->se;
+#ifdef CONFIG_SMP
int task_new = flags & ENQUEUE_WAKEUP_NEW;
int task_wakeup = flags & ENQUEUE_WAKEUP;
+#endif
/*
* If in_iowait is set, the code below may not trigger any cpufreq
@@ -4604,8 +4611,12 @@
update_cfs_shares(cfs_rq);
}
- if (!se) {
+ if (!se)
add_nr_running(rq, 1);
+
+#ifdef CONFIG_SMP
+
+ if (!se) {
if (!task_new && !rq->rd->overutilized &&
cpu_overutilized(rq->cpu))
rq->rd->overutilized = true;
@@ -4622,6 +4633,8 @@
if (task_new || task_wakeup)
update_capacity_of(cpu_of(rq));
}
+#endif /* CONFIG_SMP */
+
hrtick_update(rq);
}
@@ -4678,8 +4691,12 @@
update_cfs_shares(cfs_rq);
}
- if (!se) {
+ if (!se)
sub_nr_running(rq, 1);
+
+#ifdef CONFIG_SMP
+
+ if (!se) {
schedtune_dequeue_task(p, cpu_of(rq));
/*
@@ -4697,6 +4714,9 @@
set_cfs_cpu_capacity(cpu_of(rq), false, 0);
}
}
+
+#endif /* CONFIG_SMP */
+
hrtick_update(rq);
}
@@ -6376,6 +6396,8 @@
{
remove_entity_load_avg(&p->se);
}
+#else
+#define task_fits_max(p, cpu) true
#endif /* CONFIG_SMP */
static unsigned long
@@ -9313,10 +9335,13 @@
if (static_branch_unlikely(&sched_numa_balancing))
task_tick_numa(rq, curr);
+#ifdef CONFIG_SMP
if (!rq->rd->overutilized && cpu_overutilized(task_cpu(curr)))
rq->rd->overutilized = true;
rq->misfit_task = !task_fits_max(curr, rq->cpu);
+#endif
+
}
/*
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 77158fe..ba2efc7 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -1328,6 +1328,7 @@
#ifdef CONFIG_SMP
+extern void init_max_cpu_capacity(struct max_cpu_capacity *mcc);
extern void update_group_capacity(struct sched_domain *sd, int cpu);
extern void trigger_load_balance(struct rq *rq);
@@ -1432,8 +1433,6 @@
static inline void sched_update_tick_dependency(struct rq *rq) { }
#endif
-extern void init_max_cpu_capacity(struct max_cpu_capacity *mcc);
-
static inline void __add_nr_running(struct rq *rq, unsigned count)
{
unsigned prev_nr = rq->nr_running;