aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorAndrey Konovalov <andrey.konovalov@linaro.org>2013-05-05 02:40:34 +0400
committerAndrey Konovalov <andrey.konovalov@linaro.org>2013-05-05 02:40:34 +0400
commite5f042c6edebec55bb20a5e399f892766ac65411 (patch)
treec88e8a6bdeae93ec91bc2a8611a590672f52a397
parentc1be5a5b1b355d40e6cf79cc979eb66dafa24ad1 (diff)
parente695239d5f0a553e28a1ff5f346fcc3fafab2b2f (diff)
Merge branch 'tracking-big-LITTLE-MP-master' into merge-linux-linaro-lsk
-rw-r--r--Documentation/devicetree/bindings/arm/pmu.txt3
-rw-r--r--Documentation/kernel-parameters.txt9
-rw-r--r--arch/arm/Kconfig85
-rw-r--r--arch/arm/include/asm/pmu.h12
-rw-r--r--arch/arm/include/asm/topology.h34
-rw-r--r--arch/arm/kernel/hw_breakpoint.c3
-rw-r--r--arch/arm/kernel/perf_event.c19
-rw-r--r--arch/arm/kernel/perf_event_cpu.c117
-rw-r--r--arch/arm/kernel/perf_event_v7.c57
-rw-r--r--arch/arm/kernel/topology.c132
-rw-r--r--include/linux/sched.h12
-rw-r--r--include/trace/events/sched.h153
-rw-r--r--kernel/irq/irqdesc.c21
-rw-r--r--kernel/sched/core.c4
-rw-r--r--kernel/sched/debug.c3
-rw-r--r--kernel/sched/fair.c1021
-rw-r--r--kernel/sched/sched.h13
-rw-r--r--linaro/configs/big-LITTLE-MP.conf13
18 files changed, 1663 insertions, 48 deletions
diff --git a/Documentation/devicetree/bindings/arm/pmu.txt b/Documentation/devicetree/bindings/arm/pmu.txt
index 343781b9f24..4ce82d045a6 100644
--- a/Documentation/devicetree/bindings/arm/pmu.txt
+++ b/Documentation/devicetree/bindings/arm/pmu.txt
@@ -16,6 +16,9 @@ Required properties:
"arm,arm1176-pmu"
"arm,arm1136-pmu"
- interrupts : 1 combined interrupt or 1 per core.
+- cluster : a phandle to the cluster to which it belongs
+ If there are more than one cluster with same CPU type
+ then there should be separate PMU nodes per cluster.
Example:
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 8ccbf27aead..69e11cfa94e 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1212,6 +1212,15 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
See comment before ip2_setup() in
drivers/char/ip2/ip2base.c.
+ irqaffinity= [SMP] Set the default irq affinity mask
+ Format:
+ <cpu number>,...,<cpu number>
+ or
+ <cpu number>-<cpu number>
+ (must be a positive range in ascending order)
+ or a mixture
+ <cpu number>,...,<cpu number>-<cpu number>
+
irqfixup [HW]
When an interrupt is not handled search all handlers
for it. Intended to get systems with badly broken
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 1cacda426a0..fbd3a07f20a 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1588,6 +1588,91 @@ config SCHED_SMT
MultiThreading at a cost of slightly increased overhead in some
places. If unsure say N here.
+config DISABLE_CPU_SCHED_DOMAIN_BALANCE
+ bool "(EXPERIMENTAL) Disable CPU level scheduler load-balancing"
+ help
+ Disables scheduler load-balancing at CPU sched domain level.
+
+config SCHED_HMP
+ bool "(EXPERIMENTAL) Heterogenous multiprocessor scheduling"
+ depends on DISABLE_CPU_SCHED_DOMAIN_BALANCE && SCHED_MC && FAIR_GROUP_SCHED && !SCHED_AUTOGROUP
+ help
+ Experimental scheduler optimizations for heterogeneous platforms.
+ Attempts to introspectively select task affinity to optimize power
+ and performance. Basic support for multiple (>2) cpu types is in place,
+ but it has only been tested with two types of cpus.
+ There is currently no support for migration of task groups, hence
+ !SCHED_AUTOGROUP. Furthermore, normal load-balancing must be disabled
+ between cpus of different type (DISABLE_CPU_SCHED_DOMAIN_BALANCE).
+
+config SCHED_HMP_PRIO_FILTER
+ bool "(EXPERIMENTAL) Filter HMP migrations by task priority"
+ depends on SCHED_HMP
+ default y
+ help
+ Enables task priority based HMP migration filter. Any task with
+ a NICE value above the threshold will always be on low-power cpus
+ with less compute capacity.
+
+config SCHED_HMP_PRIO_FILTER_VAL
+ int "NICE priority threshold"
+ default 5
+ depends on SCHED_HMP_PRIO_FILTER
+
+config HMP_FAST_CPU_MASK
+ string "HMP scheduler fast CPU mask"
+ depends on SCHED_HMP
+ help
+ Leave empty to use device tree information.
+ Specify the cpuids of the fast CPUs in the system as a list string,
+ e.g. cpuid 0+1 should be specified as 0-1.
+
+config HMP_SLOW_CPU_MASK
+ string "HMP scheduler slow CPU mask"
+ depends on SCHED_HMP
+ help
+ Leave empty to use device tree information.
+ Specify the cpuids of the slow CPUs in the system as a list string,
+ e.g. cpuid 0+1 should be specified as 0-1.
+
+config HMP_VARIABLE_SCALE
+ bool "Allows changing the load tracking scale through sysfs"
+ depends on SCHED_HMP
+ help
+ When turned on, this option exports the thresholds and load average
+ period value for the load tracking patches through sysfs.
+ The values can be modified to change the rate of load accumulation
+ and the thresholds used for HMP migration.
+ The load_avg_period_ms is the time in ms to reach a load average of
+ 0.5 for an idle task of 0 load average ratio that start a busy loop.
+ The up_threshold and down_threshold is the value to go to a faster
+ CPU or to go back to a slower cpu.
+ The {up,down}_threshold are devided by 1024 before being compared
+ to the load average.
+ For examples, with load_avg_period_ms = 128 and up_threshold = 512,
+ a running task with a load of 0 will be migrated to a bigger CPU after
+ 128ms, because after 128ms its load_avg_ratio is 0.5 and the real
+ up_threshold is 0.5.
+ This patch has the same behavior as changing the Y of the load
+ average computation to
+ (1002/1024)^(LOAD_AVG_PERIOD/load_avg_period_ms)
+ but it remove intermadiate overflows in computation.
+
+config HMP_FREQUENCY_INVARIANT_SCALE
+ bool "(EXPERIMENTAL) Frequency-Invariant Tracked Load for HMP"
+ depends on HMP_VARIABLE_SCALE && CPU_FREQ
+ help
+ Scales the current load contribution in line with the frequency
+ of the CPU that the task was executed on.
+ In this version, we use a simple linear scale derived from the
+ maximum frequency reported by CPUFreq.
+ Restricting tracked load to be scaled by the CPU's frequency
+ represents the consumption of possible compute capacity
+ (rather than consumption of actual instantaneous capacity as
+ normal) and allows the HMP migration's simple threshold
+ migration strategy to interact more predictably with CPUFreq's
+ asynchronous compute capacity changes.
+
config HAVE_ARM_SCU
bool
help
diff --git a/arch/arm/include/asm/pmu.h b/arch/arm/include/asm/pmu.h
index f24edad26c7..0cd7824ca76 100644
--- a/arch/arm/include/asm/pmu.h
+++ b/arch/arm/include/asm/pmu.h
@@ -62,9 +62,19 @@ struct pmu_hw_events {
raw_spinlock_t pmu_lock;
};
+struct cpupmu_regs {
+ u32 pmc;
+ u32 pmcntenset;
+ u32 pmuseren;
+ u32 pmintenset;
+ u32 pmxevttype[8];
+ u32 pmxevtcnt[8];
+};
+
struct arm_pmu {
struct pmu pmu;
cpumask_t active_irqs;
+ cpumask_t valid_cpus;
char *name;
irqreturn_t (*handle_irq)(int irq_num, void *dev);
void (*enable)(struct perf_event *event);
@@ -81,6 +91,8 @@ struct arm_pmu {
int (*request_irq)(struct arm_pmu *, irq_handler_t handler);
void (*free_irq)(struct arm_pmu *);
int (*map_event)(struct perf_event *event);
+ void (*save_regs)(struct arm_pmu *, struct cpupmu_regs *);
+ void (*restore_regs)(struct arm_pmu *, struct cpupmu_regs *);
int num_events;
atomic_t active_events;
struct mutex reserve_mutex;
diff --git a/arch/arm/include/asm/topology.h b/arch/arm/include/asm/topology.h
index 58b8b84adcd..983fa7c153a 100644
--- a/arch/arm/include/asm/topology.h
+++ b/arch/arm/include/asm/topology.h
@@ -26,11 +26,45 @@ extern struct cputopo_arm cpu_topology[NR_CPUS];
void init_cpu_topology(void);
void store_cpu_topology(unsigned int cpuid);
const struct cpumask *cpu_coregroup_mask(int cpu);
+int cluster_to_logical_mask(unsigned int socket_id, cpumask_t *cluster_mask);
+
+#ifdef CONFIG_DISABLE_CPU_SCHED_DOMAIN_BALANCE
+/* Common values for CPUs */
+#ifndef SD_CPU_INIT
+#define SD_CPU_INIT (struct sched_domain) { \
+ .min_interval = 1, \
+ .max_interval = 4, \
+ .busy_factor = 64, \
+ .imbalance_pct = 125, \
+ .cache_nice_tries = 1, \
+ .busy_idx = 2, \
+ .idle_idx = 1, \
+ .newidle_idx = 0, \
+ .wake_idx = 0, \
+ .forkexec_idx = 0, \
+ \
+ .flags = 0*SD_LOAD_BALANCE \
+ | 1*SD_BALANCE_NEWIDLE \
+ | 1*SD_BALANCE_EXEC \
+ | 1*SD_BALANCE_FORK \
+ | 0*SD_BALANCE_WAKE \
+ | 1*SD_WAKE_AFFINE \
+ | 0*SD_SHARE_CPUPOWER \
+ | 0*SD_SHARE_PKG_RESOURCES \
+ | 0*SD_SERIALIZE \
+ , \
+ .last_balance = jiffies, \
+ .balance_interval = 1, \
+}
+#endif
+#endif /* CONFIG_DISABLE_CPU_SCHED_DOMAIN_BALANCE */
#else
static inline void init_cpu_topology(void) { }
static inline void store_cpu_topology(unsigned int cpuid) { }
+static inline int cluster_to_logical_mask(unsigned int socket_id,
+ cpumask_t *cluster_mask) { return -EINVAL; }
#endif
diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c
index 1fd749ee4a1..1b803117ed9 100644
--- a/arch/arm/kernel/hw_breakpoint.c
+++ b/arch/arm/kernel/hw_breakpoint.c
@@ -1049,7 +1049,8 @@ static struct notifier_block dbg_cpu_pm_nb = {
static void __init pm_init(void)
{
- cpu_pm_register_notifier(&dbg_cpu_pm_nb);
+ if (has_ossr)
+ cpu_pm_register_notifier(&dbg_cpu_pm_nb);
}
#else
static inline void pm_init(void)
diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
index 8c3094d0f7b..d847c622a7b 100644
--- a/arch/arm/kernel/perf_event.c
+++ b/arch/arm/kernel/perf_event.c
@@ -12,6 +12,7 @@
*/
#define pr_fmt(fmt) "hw perfevents: " fmt
+#include <linux/cpumask.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
@@ -81,6 +82,9 @@ armpmu_map_event(struct perf_event *event,
return armpmu_map_cache_event(cache_map, config);
case PERF_TYPE_RAW:
return armpmu_map_raw_event(raw_event_mask, config);
+ default:
+ if (event->attr.type >= PERF_TYPE_MAX)
+ return armpmu_map_raw_event(raw_event_mask, config);
}
return -ENOENT;
@@ -158,6 +162,8 @@ armpmu_stop(struct perf_event *event, int flags)
struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
struct hw_perf_event *hwc = &event->hw;
+ if (!cpumask_test_cpu(smp_processor_id(), &armpmu->valid_cpus))
+ return;
/*
* ARM pmu always has to update the counter, so ignore
* PERF_EF_UPDATE, see comments in armpmu_start().
@@ -174,6 +180,8 @@ static void armpmu_start(struct perf_event *event, int flags)
struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
struct hw_perf_event *hwc = &event->hw;
+ if (!cpumask_test_cpu(smp_processor_id(), &armpmu->valid_cpus))
+ return;
/*
* ARM pmu always has to reprogram the period, so ignore
* PERF_EF_RELOAD, see the comment below.
@@ -201,6 +209,9 @@ armpmu_del(struct perf_event *event, int flags)
struct hw_perf_event *hwc = &event->hw;
int idx = hwc->idx;
+ if (!cpumask_test_cpu(smp_processor_id(), &armpmu->valid_cpus))
+ return;
+
armpmu_stop(event, PERF_EF_UPDATE);
hw_events->events[idx] = NULL;
clear_bit(idx, hw_events->used_mask);
@@ -217,6 +228,10 @@ armpmu_add(struct perf_event *event, int flags)
int idx;
int err = 0;
+ /* An event following a process won't be stopped earlier */
+ if (!cpumask_test_cpu(smp_processor_id(), &armpmu->valid_cpus))
+ return 0;
+
perf_pmu_disable(event->pmu);
/* If we don't have a space for the counter then finish early. */
@@ -416,6 +431,10 @@ static int armpmu_event_init(struct perf_event *event)
int err = 0;
atomic_t *active_events = &armpmu->active_events;
+ if (event->cpu != -1 &&
+ !cpumask_test_cpu(event->cpu, &armpmu->valid_cpus))
+ return -ENOENT;
+
/* does not support taken branch sampling */
if (has_branch_stack(event))
return -EOPNOTSUPP;
diff --git a/arch/arm/kernel/perf_event_cpu.c b/arch/arm/kernel/perf_event_cpu.c
index 1f2740e3dbc..0b48a38e3cf 100644
--- a/arch/arm/kernel/perf_event_cpu.c
+++ b/arch/arm/kernel/perf_event_cpu.c
@@ -19,6 +19,7 @@
#define pr_fmt(fmt) "CPU PMU: " fmt
#include <linux/bitmap.h>
+#include <linux/cpu_pm.h>
#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/of.h>
@@ -31,33 +32,36 @@
#include <asm/pmu.h>
/* Set at runtime when we know what CPU type we are. */
-static struct arm_pmu *cpu_pmu;
+static DEFINE_PER_CPU(struct arm_pmu *, cpu_pmu);
static DEFINE_PER_CPU(struct perf_event * [ARMPMU_MAX_HWEVENTS], hw_events);
static DEFINE_PER_CPU(unsigned long [BITS_TO_LONGS(ARMPMU_MAX_HWEVENTS)], used_mask);
static DEFINE_PER_CPU(struct pmu_hw_events, cpu_hw_events);
+static DEFINE_PER_CPU(struct cpupmu_regs, cpu_pmu_regs);
+
/*
* Despite the names, these two functions are CPU-specific and are used
* by the OProfile/perf code.
*/
const char *perf_pmu_name(void)
{
- if (!cpu_pmu)
+ struct arm_pmu *pmu = per_cpu(cpu_pmu, 0);
+ if (!pmu)
return NULL;
- return cpu_pmu->name;
+ return pmu->name;
}
EXPORT_SYMBOL_GPL(perf_pmu_name);
int perf_num_counters(void)
{
- int max_events = 0;
+ struct arm_pmu *pmu = per_cpu(cpu_pmu, 0);
- if (cpu_pmu != NULL)
- max_events = cpu_pmu->num_events;
+ if (!pmu)
+ return 0;
- return max_events;
+ return pmu->num_events;
}
EXPORT_SYMBOL_GPL(perf_num_counters);
@@ -75,11 +79,13 @@ static void cpu_pmu_free_irq(struct arm_pmu *cpu_pmu)
{
int i, irq, irqs;
struct platform_device *pmu_device = cpu_pmu->plat_device;
+ int cpu = -1;
irqs = min(pmu_device->num_resources, num_possible_cpus());
for (i = 0; i < irqs; ++i) {
- if (!cpumask_test_and_clear_cpu(i, &cpu_pmu->active_irqs))
+ cpu = cpumask_next(cpu, &cpu_pmu->valid_cpus);
+ if (!cpumask_test_and_clear_cpu(cpu, &cpu_pmu->active_irqs))
continue;
irq = platform_get_irq(pmu_device, i);
if (irq >= 0)
@@ -91,6 +97,7 @@ static int cpu_pmu_request_irq(struct arm_pmu *cpu_pmu, irq_handler_t handler)
{
int i, err, irq, irqs;
struct platform_device *pmu_device = cpu_pmu->plat_device;
+ int cpu = -1;
if (!pmu_device)
return -ENODEV;
@@ -103,6 +110,7 @@ static int cpu_pmu_request_irq(struct arm_pmu *cpu_pmu, irq_handler_t handler)
for (i = 0; i < irqs; ++i) {
err = 0;
+ cpu = cpumask_next(cpu, &cpu_pmu->valid_cpus);
irq = platform_get_irq(pmu_device, i);
if (irq < 0)
continue;
@@ -112,7 +120,7 @@ static int cpu_pmu_request_irq(struct arm_pmu *cpu_pmu, irq_handler_t handler)
* assume that we're running on a uniprocessor machine and
* continue. Otherwise, continue without this interrupt.
*/
- if (irq_set_affinity(irq, cpumask_of(i)) && irqs > 1) {
+ if (irq_set_affinity(irq, cpumask_of(cpu)) && irqs > 1) {
pr_warning("unable to set irq affinity (irq=%d, cpu=%u)\n",
irq, i);
continue;
@@ -126,7 +134,7 @@ static int cpu_pmu_request_irq(struct arm_pmu *cpu_pmu, irq_handler_t handler)
return err;
}
- cpumask_set_cpu(i, &cpu_pmu->active_irqs);
+ cpumask_set_cpu(cpu, &cpu_pmu->active_irqs);
}
return 0;
@@ -135,7 +143,7 @@ static int cpu_pmu_request_irq(struct arm_pmu *cpu_pmu, irq_handler_t handler)
static void cpu_pmu_init(struct arm_pmu *cpu_pmu)
{
int cpu;
- for_each_possible_cpu(cpu) {
+ for_each_cpu_mask(cpu, cpu_pmu->valid_cpus) {
struct pmu_hw_events *events = &per_cpu(cpu_hw_events, cpu);
events->events = per_cpu(hw_events, cpu);
events->used_mask = per_cpu(used_mask, cpu);
@@ -148,7 +156,7 @@ static void cpu_pmu_init(struct arm_pmu *cpu_pmu)
/* Ensure the PMU has sane values out of reset. */
if (cpu_pmu->reset)
- on_each_cpu(cpu_pmu->reset, cpu_pmu, 1);
+ on_each_cpu_mask(&cpu_pmu->valid_cpus, cpu_pmu->reset, cpu_pmu, 1);
}
/*
@@ -160,21 +168,46 @@ static void cpu_pmu_init(struct arm_pmu *cpu_pmu)
static int __cpuinit cpu_pmu_notify(struct notifier_block *b,
unsigned long action, void *hcpu)
{
+ struct arm_pmu *pmu = per_cpu(cpu_pmu, (long)hcpu);
+
if ((action & ~CPU_TASKS_FROZEN) != CPU_STARTING)
return NOTIFY_DONE;
- if (cpu_pmu && cpu_pmu->reset)
- cpu_pmu->reset(cpu_pmu);
+ if (pmu && pmu->reset)
+ pmu->reset(pmu);
else
return NOTIFY_DONE;
return NOTIFY_OK;
}
+static int cpu_pmu_pm_notify(struct notifier_block *b,
+ unsigned long action, void *hcpu)
+{
+ int cpu = smp_processor_id();
+ struct arm_pmu *pmu = per_cpu(cpu_pmu, cpu);
+ struct cpupmu_regs *pmuregs = &per_cpu(cpu_pmu_regs, cpu);
+
+ if (!pmu)
+ return NOTIFY_DONE;
+
+ if (action == CPU_PM_ENTER && pmu->save_regs) {
+ pmu->save_regs(pmu, pmuregs);
+ } else if (action == CPU_PM_EXIT && pmu->restore_regs) {
+ pmu->restore_regs(pmu, pmuregs);
+ }
+
+ return NOTIFY_OK;
+}
+
static struct notifier_block __cpuinitdata cpu_pmu_hotplug_notifier = {
.notifier_call = cpu_pmu_notify,
};
+static struct notifier_block __cpuinitdata cpu_pmu_pm_notifier = {
+ .notifier_call = cpu_pmu_pm_notify,
+};
+
/*
* PMU platform driver and devicetree bindings.
*/
@@ -246,6 +279,9 @@ static int probe_current_pmu(struct arm_pmu *pmu)
}
}
+ /* assume PMU support all the CPUs in this case */
+ cpumask_setall(&pmu->valid_cpus);
+
put_cpu();
return ret;
}
@@ -253,15 +289,10 @@ static int probe_current_pmu(struct arm_pmu *pmu)
static int cpu_pmu_device_probe(struct platform_device *pdev)
{
const struct of_device_id *of_id;
- int (*init_fn)(struct arm_pmu *);
struct device_node *node = pdev->dev.of_node;
struct arm_pmu *pmu;
- int ret = -ENODEV;
-
- if (cpu_pmu) {
- pr_info("attempt to register multiple PMU devices!");
- return -ENOSPC;
- }
+ int ret = 0;
+ int cpu;
pmu = kzalloc(sizeof(struct arm_pmu), GFP_KERNEL);
if (!pmu) {
@@ -270,8 +301,28 @@ static int cpu_pmu_device_probe(struct platform_device *pdev)
}
if (node && (of_id = of_match_node(cpu_pmu_of_device_ids, pdev->dev.of_node))) {
- init_fn = of_id->data;
- ret = init_fn(pmu);
+ smp_call_func_t init_fn = (smp_call_func_t)of_id->data;
+ struct device_node *ncluster;
+ int cluster = -1;
+ cpumask_t sibling_mask;
+
+ ncluster = of_parse_phandle(node, "cluster", 0);
+ if (ncluster) {
+ int len;
+ const u32 *hwid;
+ hwid = of_get_property(ncluster, "reg", &len);
+ if (hwid && len == 4)
+ cluster = be32_to_cpup(hwid);
+ }
+ /* set sibling mask to all cpu mask if socket is not specified */
+ if (cluster == -1 ||
+ cluster_to_logical_mask(cluster, &sibling_mask))
+ cpumask_setall(&sibling_mask);
+
+ smp_call_function_any(&sibling_mask, init_fn, pmu, 1);
+
+ /* now set the valid_cpus after init */
+ cpumask_copy(&pmu->valid_cpus, &sibling_mask);
} else {
ret = probe_current_pmu(pmu);
}
@@ -281,10 +332,12 @@ static int cpu_pmu_device_probe(struct platform_device *pdev)
goto out_free;
}
- cpu_pmu = pmu;
- cpu_pmu->plat_device = pdev;
- cpu_pmu_init(cpu_pmu);
- ret = armpmu_register(cpu_pmu, PERF_TYPE_RAW);
+ for_each_cpu_mask(cpu, pmu->valid_cpus)
+ per_cpu(cpu_pmu, cpu) = pmu;
+
+ pmu->plat_device = pdev;
+ cpu_pmu_init(pmu);
+ ret = armpmu_register(pmu, -1);
if (!ret)
return 0;
@@ -313,9 +366,17 @@ static int __init register_pmu_driver(void)
if (err)
return err;
+ err = cpu_pm_register_notifier(&cpu_pmu_pm_notifier);
+ if (err) {
+ unregister_cpu_notifier(&cpu_pmu_hotplug_notifier);
+ return err;
+ }
+
err = platform_driver_register(&cpu_pmu_driver);
- if (err)
+ if (err) {
+ cpu_pm_unregister_notifier(&cpu_pmu_pm_notifier);
unregister_cpu_notifier(&cpu_pmu_hotplug_notifier);
+ }
return err;
}
diff --git a/arch/arm/kernel/perf_event_v7.c b/arch/arm/kernel/perf_event_v7.c
index 039cffb053a..654db5030c3 100644
--- a/arch/arm/kernel/perf_event_v7.c
+++ b/arch/arm/kernel/perf_event_v7.c
@@ -950,6 +950,51 @@ static void armv7_pmnc_dump_regs(struct arm_pmu *cpu_pmu)
}
#endif
+static void armv7pmu_save_regs(struct arm_pmu *cpu_pmu,
+ struct cpupmu_regs *regs)
+{
+ unsigned int cnt;
+ asm volatile("mrc p15, 0, %0, c9, c12, 0" : "=r" (regs->pmc));
+ if (!(regs->pmc & ARMV7_PMNC_E))
+ return;
+
+ asm volatile("mrc p15, 0, %0, c9, c12, 1" : "=r" (regs->pmcntenset));
+ asm volatile("mrc p15, 0, %0, c9, c14, 0" : "=r" (regs->pmuseren));
+ asm volatile("mrc p15, 0, %0, c9, c14, 1" : "=r" (regs->pmintenset));
+ asm volatile("mrc p15, 0, %0, c9, c13, 0" : "=r" (regs->pmxevtcnt[0]));
+ for (cnt = ARMV7_IDX_COUNTER0;
+ cnt <= ARMV7_IDX_COUNTER_LAST(cpu_pmu); cnt++) {
+ armv7_pmnc_select_counter(cnt);
+ asm volatile("mrc p15, 0, %0, c9, c13, 1"
+ : "=r"(regs->pmxevttype[cnt]));
+ asm volatile("mrc p15, 0, %0, c9, c13, 2"
+ : "=r"(regs->pmxevtcnt[cnt]));
+ }
+ return;
+}
+
+static void armv7pmu_restore_regs(struct arm_pmu *cpu_pmu,
+ struct cpupmu_regs *regs)
+{
+ unsigned int cnt;
+ if (!(regs->pmc & ARMV7_PMNC_E))
+ return;
+
+ asm volatile("mcr p15, 0, %0, c9, c12, 1" : : "r" (regs->pmcntenset));
+ asm volatile("mcr p15, 0, %0, c9, c14, 0" : : "r" (regs->pmuseren));
+ asm volatile("mcr p15, 0, %0, c9, c14, 1" : : "r" (regs->pmintenset));
+ asm volatile("mcr p15, 0, %0, c9, c13, 0" : : "r" (regs->pmxevtcnt[0]));
+ for (cnt = ARMV7_IDX_COUNTER0;
+ cnt <= ARMV7_IDX_COUNTER_LAST(cpu_pmu); cnt++) {
+ armv7_pmnc_select_counter(cnt);
+ asm volatile("mcr p15, 0, %0, c9, c13, 1"
+ : : "r"(regs->pmxevttype[cnt]));
+ asm volatile("mcr p15, 0, %0, c9, c13, 2"
+ : : "r"(regs->pmxevtcnt[cnt]));
+ }
+ asm volatile("mcr p15, 0, %0, c9, c12, 0" : : "r" (regs->pmc));
+}
+
static void armv7pmu_enable_event(struct perf_event *event)
{
unsigned long flags;
@@ -1223,6 +1268,8 @@ static void armv7pmu_init(struct arm_pmu *cpu_pmu)
cpu_pmu->start = armv7pmu_start;
cpu_pmu->stop = armv7pmu_stop;
cpu_pmu->reset = armv7pmu_reset;
+ cpu_pmu->save_regs = armv7pmu_save_regs;
+ cpu_pmu->restore_regs = armv7pmu_restore_regs;
cpu_pmu->max_period = (1LLU << 32) - 1;
};
@@ -1240,7 +1287,7 @@ static u32 armv7_read_num_pmnc_events(void)
static int armv7_a8_pmu_init(struct arm_pmu *cpu_pmu)
{
armv7pmu_init(cpu_pmu);
- cpu_pmu->name = "ARMv7 Cortex-A8";
+ cpu_pmu->name = "ARMv7_Cortex_A8";
cpu_pmu->map_event = armv7_a8_map_event;
cpu_pmu->num_events = armv7_read_num_pmnc_events();
return 0;
@@ -1249,7 +1296,7 @@ static int armv7_a8_pmu_init(struct arm_pmu *cpu_pmu)
static int armv7_a9_pmu_init(struct arm_pmu *cpu_pmu)
{
armv7pmu_init(cpu_pmu);
- cpu_pmu->name = "ARMv7 Cortex-A9";
+ cpu_pmu->name = "ARMv7_Cortex_A9";
cpu_pmu->map_event = armv7_a9_map_event;
cpu_pmu->num_events = armv7_read_num_pmnc_events();
return 0;
@@ -1258,7 +1305,7 @@ static int armv7_a9_pmu_init(struct arm_pmu *cpu_pmu)
static int armv7_a5_pmu_init(struct arm_pmu *cpu_pmu)
{
armv7pmu_init(cpu_pmu);
- cpu_pmu->name = "ARMv7 Cortex-A5";
+ cpu_pmu->name = "ARMv7_Cortex_A5";
cpu_pmu->map_event = armv7_a5_map_event;
cpu_pmu->num_events = armv7_read_num_pmnc_events();
return 0;
@@ -1267,7 +1314,7 @@ static int armv7_a5_pmu_init(struct arm_pmu *cpu_pmu)
static int armv7_a15_pmu_init(struct arm_pmu *cpu_pmu)
{
armv7pmu_init(cpu_pmu);
- cpu_pmu->name = "ARMv7 Cortex-A15";
+ cpu_pmu->name = "ARMv7_Cortex_A15";
cpu_pmu->map_event = armv7_a15_map_event;
cpu_pmu->num_events = armv7_read_num_pmnc_events();
cpu_pmu->set_event_filter = armv7pmu_set_event_filter;
@@ -1277,7 +1324,7 @@ static int armv7_a15_pmu_init(struct arm_pmu *cpu_pmu)
static int armv7_a7_pmu_init(struct arm_pmu *cpu_pmu)
{
armv7pmu_init(cpu_pmu);
- cpu_pmu->name = "ARMv7 Cortex-A7";
+ cpu_pmu->name = "ARMv7_Cortex_A7";
cpu_pmu->map_event = armv7_a7_map_event;
cpu_pmu->num_events = armv7_read_num_pmnc_events();
cpu_pmu->set_event_filter = armv7pmu_set_event_filter;
diff --git a/arch/arm/kernel/topology.c b/arch/arm/kernel/topology.c
index 79282ebcd93..fa45fb43a62 100644
--- a/arch/arm/kernel/topology.c
+++ b/arch/arm/kernel/topology.c
@@ -22,6 +22,7 @@
#include <linux/slab.h>
#include <asm/cputype.h>
+#include <asm/smp_plat.h>
#include <asm/topology.h>
/*
@@ -287,6 +288,137 @@ void store_cpu_topology(unsigned int cpuid)
cpu_topology[cpuid].socket_id, mpidr);
}
+
+#ifdef CONFIG_SCHED_HMP
+
+static const char * const little_cores[] = {
+ "arm,cortex-a7",
+ NULL,
+};
+
+static bool is_little_cpu(struct device_node *cn)
+{
+ const char * const *lc;
+ for (lc = little_cores; *lc; lc++)
+ if (of_device_is_compatible(cn, *lc))
+ return true;
+ return false;
+}
+
+void __init arch_get_fast_and_slow_cpus(struct cpumask *fast,
+ struct cpumask *slow)
+{
+ struct device_node *cn = NULL;
+ int cpu;
+
+ cpumask_clear(fast);
+ cpumask_clear(slow);
+
+ /*
+ * Use the config options if they are given. This helps testing
+ * HMP scheduling on systems without a big.LITTLE architecture.
+ */
+ if (strlen(CONFIG_HMP_FAST_CPU_MASK) && strlen(CONFIG_HMP_SLOW_CPU_MASK)) {
+ if (cpulist_parse(CONFIG_HMP_FAST_CPU_MASK, fast))
+ WARN(1, "Failed to parse HMP fast cpu mask!\n");
+ if (cpulist_parse(CONFIG_HMP_SLOW_CPU_MASK, slow))
+ WARN(1, "Failed to parse HMP slow cpu mask!\n");
+ return;
+ }
+
+ /*
+ * Else, parse device tree for little cores.
+ */
+ while ((cn = of_find_node_by_type(cn, "cpu"))) {
+
+ const u32 *mpidr;
+ int len;
+
+ mpidr = of_get_property(cn, "reg", &len);
+ if (!mpidr || len != 4) {
+ pr_err("* %s missing reg property\n", cn->full_name);
+ continue;
+ }
+
+ cpu = get_logical_index(be32_to_cpup(mpidr));
+ if (cpu == -EINVAL) {
+ pr_err("couldn't get logical index for mpidr %x\n",
+ be32_to_cpup(mpidr));
+ break;
+ }
+
+ if (is_little_cpu(cn))
+ cpumask_set_cpu(cpu, slow);
+ else
+ cpumask_set_cpu(cpu, fast);
+ }
+
+ if (!cpumask_empty(fast) && !cpumask_empty(slow))
+ return;
+
+ /*
+ * We didn't find both big and little cores so let's call all cores
+ * fast as this will keep the system running, with all cores being
+ * treated equal.
+ */
+ cpumask_setall(fast);
+ cpumask_clear(slow);
+}
+
+void __init arch_get_hmp_domains(struct list_head *hmp_domains_list)
+{
+ struct cpumask hmp_fast_cpu_mask;
+ struct cpumask hmp_slow_cpu_mask;
+ struct hmp_domain *domain;
+
+ arch_get_fast_and_slow_cpus(&hmp_fast_cpu_mask, &hmp_slow_cpu_mask);
+
+ /*
+ * Initialize hmp_domains
+ * Must be ordered with respect to compute capacity.
+ * Fastest domain at head of list.
+ */
+ if(!cpumask_empty(&hmp_slow_cpu_mask)) {
+ domain = (struct hmp_domain *)
+ kmalloc(sizeof(struct hmp_domain), GFP_KERNEL);
+ cpumask_copy(&domain->cpus, &hmp_slow_cpu_mask);
+ list_add(&domain->hmp_domains, hmp_domains_list);
+ }
+ domain = (struct hmp_domain *)
+ kmalloc(sizeof(struct hmp_domain), GFP_KERNEL);
+ cpumask_copy(&domain->cpus, &hmp_fast_cpu_mask);
+ list_add(&domain->hmp_domains, hmp_domains_list);
+}
+#endif /* CONFIG_SCHED_HMP */
+
+
+/*
+ * cluster_to_logical_mask - return cpu logical mask of CPUs in a cluster
+ * @socket_id: cluster HW identifier
+ * @cluster_mask: the cpumask location to be initialized, modified by the
+ * function only if return value == 0
+ *
+ * Return:
+ *
+ * 0 on success
+ * -EINVAL if cluster_mask is NULL or there is no record matching socket_id
+ */
+int cluster_to_logical_mask(unsigned int socket_id, cpumask_t *cluster_mask)
+{
+ int cpu;
+
+ if (!cluster_mask)
+ return -EINVAL;
+
+ for_each_online_cpu(cpu)
+ if (socket_id == topology_physical_package_id(cpu)) {
+ cpumask_copy(cluster_mask, topology_core_cpumask(cpu));
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
/*
* init_cpu_topology is called at boot when only one cpu is running
* which prevent simultaneous write access to cpu_topology array
diff --git a/include/linux/sched.h b/include/linux/sched.h
index e692a022527..dfc1f8a1bf7 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -986,6 +986,12 @@ unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu);
bool cpus_share_cache(int this_cpu, int that_cpu);
+#ifdef CONFIG_SCHED_HMP
+struct hmp_domain {
+ struct cpumask cpus;
+ struct list_head hmp_domains;
+};
+#endif /* CONFIG_SCHED_HMP */
#else /* CONFIG_SMP */
struct sched_domain_attr;
@@ -1098,6 +1104,12 @@ struct sched_avg {
u64 last_runnable_update;
s64 decay_count;
unsigned long load_avg_contrib;
+ unsigned long load_avg_ratio;
+#ifdef CONFIG_SCHED_HMP
+ u64 hmp_last_up_migration;
+ u64 hmp_last_down_migration;
+#endif
+ u32 usage_avg_sum;
};
#ifdef CONFIG_SCHEDSTATS
diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h
index e5586caff67..203e8e9933b 100644
--- a/include/trace/events/sched.h
+++ b/include/trace/events/sched.h
@@ -430,6 +430,159 @@ TRACE_EVENT(sched_pi_setprio,
__entry->oldprio, __entry->newprio)
);
+/*
+ * Tracepoint for showing tracked load contribution.
+ */
+TRACE_EVENT(sched_task_load_contrib,
+
+ TP_PROTO(struct task_struct *tsk, unsigned long load_contrib),
+
+ TP_ARGS(tsk, load_contrib),
+
+ TP_STRUCT__entry(
+ __array(char, comm, TASK_COMM_LEN)
+ __field(pid_t, pid)
+ __field(unsigned long, load_contrib)
+ ),
+
+ TP_fast_assign(
+ memcpy(__entry->comm, tsk->comm, TASK_COMM_LEN);
+ __entry->pid = tsk->pid;
+ __entry->load_contrib = load_contrib;
+ ),
+
+ TP_printk("comm=%s pid=%d load_contrib=%lu",
+ __entry->comm, __entry->pid,
+ __entry->load_contrib)
+);
+
+/*
+ * Tracepoint for showing tracked task runnable ratio [0..1023].
+ */
+TRACE_EVENT(sched_task_runnable_ratio,
+
+ TP_PROTO(struct task_struct *tsk, unsigned long ratio),
+
+ TP_ARGS(tsk, ratio),
+
+ TP_STRUCT__entry(
+ __array(char, comm, TASK_COMM_LEN)
+ __field(pid_t, pid)
+ __field(unsigned long, ratio)
+ ),
+
+ TP_fast_assign(
+ memcpy(__entry->comm, tsk->comm, TASK_COMM_LEN);
+ __entry->pid = tsk->pid;
+ __entry->ratio = ratio;
+ ),
+
+ TP_printk("comm=%s pid=%d ratio=%lu",
+ __entry->comm, __entry->pid,
+ __entry->ratio)
+);
+
+/*
+ * Tracepoint for showing tracked rq runnable ratio [0..1023].
+ */
+TRACE_EVENT(sched_rq_runnable_ratio,
+
+ TP_PROTO(int cpu, unsigned long ratio),
+
+ TP_ARGS(cpu, ratio),
+
+ TP_STRUCT__entry(
+ __field(int, cpu)
+ __field(unsigned long, ratio)
+ ),
+
+ TP_fast_assign(
+ __entry->cpu = cpu;
+ __entry->ratio = ratio;
+ ),
+
+ TP_printk("cpu=%d ratio=%lu",
+ __entry->cpu,
+ __entry->ratio)
+);
+
+/*
+ * Tracepoint for showing tracked rq runnable load.
+ */
+TRACE_EVENT(sched_rq_runnable_load,
+
+ TP_PROTO(int cpu, u64 load),
+
+ TP_ARGS(cpu, load),
+
+ TP_STRUCT__entry(
+ __field(int, cpu)
+ __field(u64, load)
+ ),
+
+ TP_fast_assign(
+ __entry->cpu = cpu;
+ __entry->load = load;
+ ),
+
+ TP_printk("cpu=%d load=%llu",
+ __entry->cpu,
+ __entry->load)
+);
+
+/*
+ * Tracepoint for showing tracked task cpu usage ratio [0..1023].
+ */
+TRACE_EVENT(sched_task_usage_ratio,
+
+ TP_PROTO(struct task_struct *tsk, unsigned long ratio),
+
+ TP_ARGS(tsk, ratio),
+
+ TP_STRUCT__entry(
+ __array(char, comm, TASK_COMM_LEN)
+ __field(pid_t, pid)
+ __field(unsigned long, ratio)
+ ),
+
+ TP_fast_assign(
+ memcpy(__entry->comm, tsk->comm, TASK_COMM_LEN);
+ __entry->pid = tsk->pid;
+ __entry->ratio = ratio;
+ ),
+
+ TP_printk("comm=%s pid=%d ratio=%lu",
+ __entry->comm, __entry->pid,
+ __entry->ratio)
+);
+
+/*
+ * Tracepoint for HMP (CONFIG_SCHED_HMP) task migrations.
+ */
+TRACE_EVENT(sched_hmp_migrate,
+
+ TP_PROTO(struct task_struct *tsk, int dest, int force),
+
+ TP_ARGS(tsk, dest, force),
+
+ TP_STRUCT__entry(
+ __array(char, comm, TASK_COMM_LEN)
+ __field(pid_t, pid)
+ __field(int, dest)
+ __field(int, force)
+ ),
+
+ TP_fast_assign(
+ memcpy(__entry->comm, tsk->comm, TASK_COMM_LEN);
+ __entry->pid = tsk->pid;
+ __entry->dest = dest;
+ __entry->force = force;
+ ),
+
+ TP_printk("comm=%s pid=%d dest=%d force=%d",
+ __entry->comm, __entry->pid,
+ __entry->dest, __entry->force)
+);
#endif /* _TRACE_SCHED_H */
/* This part must be outside protection */
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 192a302d6cf..473b2b6eccb 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -23,10 +23,27 @@
static struct lock_class_key irq_desc_lock_class;
#if defined(CONFIG_SMP)
+static int __init irq_affinity_setup(char *str)
+{
+ zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
+ cpulist_parse(str, irq_default_affinity);
+ /*
+ * Set at least the boot cpu. We don't want to end up with
+ * bugreports caused by random comandline masks
+ */
+ cpumask_set_cpu(smp_processor_id(), irq_default_affinity);
+ return 1;
+}
+__setup("irqaffinity=", irq_affinity_setup);
+
static void __init init_irq_default_affinity(void)
{
- alloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
- cpumask_setall(irq_default_affinity);
+#ifdef CONFIG_CPUMASK_OFFSTACK
+ if (!irq_default_affinity)
+ zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
+#endif
+ if (cpumask_empty(irq_default_affinity))
+ cpumask_setall(irq_default_affinity);
}
#else
static void __init init_irq_default_affinity(void)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 67d04651f44..5df340c3625 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1571,6 +1571,10 @@ static void __sched_fork(struct task_struct *p)
#if defined(CONFIG_SMP) && defined(CONFIG_FAIR_GROUP_SCHED)
p->se.avg.runnable_avg_period = 0;
p->se.avg.runnable_avg_sum = 0;
+#ifdef CONFIG_SCHED_HMP
+ p->se.avg.hmp_last_up_migration = 0;
+ p->se.avg.hmp_last_down_migration = 0;
+#endif
#endif
#ifdef CONFIG_SCHEDSTATS
memset(&p->se.statistics, 0, sizeof(p->se.statistics));
diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index 75024a67352..fbd8caa83ef 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -94,6 +94,7 @@ static void print_cfs_group_stats(struct seq_file *m, int cpu, struct task_group
#ifdef CONFIG_SMP
P(se->avg.runnable_avg_sum);
P(se->avg.runnable_avg_period);
+ P(se->avg.usage_avg_sum);
P(se->avg.load_avg_contrib);
P(se->avg.decay_count);
#endif
@@ -223,6 +224,8 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
cfs_rq->tg_runnable_contrib);
SEQ_printf(m, " .%-30s: %d\n", "tg->runnable_avg",
atomic_read(&cfs_rq->tg->runnable_avg));
+ SEQ_printf(m, " .%-30s: %d\n", "tg->usage_avg",
+ atomic_read(&cfs_rq->tg->usage_avg));
#endif
print_cfs_group_stats(m, cpu, cfs_rq->tg);
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 7a33e5986fc..5ecfb1be889 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -31,9 +31,20 @@
#include <linux/task_work.h>
#include <trace/events/sched.h>
+#ifdef CONFIG_HMP_VARIABLE_SCALE
+#include <linux/sysfs.h>
+#include <linux/vmalloc.h>
+#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
+/* Include cpufreq header to add a notifier so that cpu frequency
+ * scaling can track the current CPU frequency
+ */
+#include <linux/cpufreq.h>
+#endif /* CONFIG_HMP_FREQUENCY_INVARIANT_SCALE */
+#endif /* CONFIG_HMP_VARIABLE_SCALE */
#include "sched.h"
+
/*
* Targeted preemption latency for CPU-bound tasks:
* (default: 6ms * (1 + ilog(ncpus)), units: nanoseconds)
@@ -1200,8 +1211,95 @@ static u32 __compute_runnable_contrib(u64 n)
return contrib + runnable_avg_yN_sum[n];
}
-/*
- * We can represent the historical contribution to runnable average as the
+#ifdef CONFIG_HMP_VARIABLE_SCALE
+
+#define HMP_VARIABLE_SCALE_SHIFT 16ULL
+struct hmp_global_attr {
+ struct attribute attr;
+ ssize_t (*show)(struct kobject *kobj,
+ struct attribute *attr, char *buf);
+ ssize_t (*store)(struct kobject *a, struct attribute *b,
+ const char *c, size_t count);
+ int *value;
+ int (*to_sysfs)(int);
+ int (*from_sysfs)(int);
+};
+
+#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
+#define HMP_DATA_SYSFS_MAX 4
+#else
+#define HMP_DATA_SYSFS_MAX 3
+#endif
+
+struct hmp_data_struct {
+#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
+ int freqinvar_load_scale_enabled;
+#endif
+ int multiplier; /* used to scale the time delta */
+ struct attribute_group attr_group;
+ struct attribute *attributes[HMP_DATA_SYSFS_MAX + 1];
+ struct hmp_global_attr attr[HMP_DATA_SYSFS_MAX];
+} hmp_data;
+
+static u64 hmp_variable_scale_convert(u64 delta);
+#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
+/* Frequency-Invariant Load Modification:
+ * Loads are calculated as in PJT's patch however we also scale the current
+ * contribution in line with the frequency of the CPU that the task was
+ * executed on.
+ * In this version, we use a simple linear scale derived from the maximum
+ * frequency reported by CPUFreq. As an example:
+ *
+ * Consider that we ran a task for 100% of the previous interval.
+ *
+ * Our CPU was under asynchronous frequency control through one of the
+ * CPUFreq governors.
+ *
+ * The CPUFreq governor reports that it is able to scale the CPU between
+ * 500MHz and 1GHz.
+ *
+ * During the period, the CPU was running at 1GHz.
+ *
+ * In this case, our load contribution for that period is calculated as
+ * 1 * (number_of_active_microseconds)
+ *
+ * This results in our task being able to accumulate maximum load as normal.
+ *
+ *
+ * Consider now that our CPU was executing at 500MHz.
+ *
+ * We now scale the load contribution such that it is calculated as
+ * 0.5 * (number_of_active_microseconds)
+ *
+ * Our task can only record 50% maximum load during this period.
+ *
+ * This represents the task consuming 50% of the CPU's *possible* compute
+ * capacity. However the task did consume 100% of the CPU's *available*
+ * compute capacity which is the value seen by the CPUFreq governor and
+ * user-side CPU Utilization tools.
+ *
+ * Restricting tracked load to be scaled by the CPU's frequency accurately
+ * represents the consumption of possible compute capacity and allows the
+ * HMP migration's simple threshold migration strategy to interact more
+ * predictably with CPUFreq's asynchronous compute capacity changes.
+ */
+#define SCHED_FREQSCALE_SHIFT 10
+struct cpufreq_extents {
+ u32 curr_scale;
+ u32 min;
+ u32 max;
+ u32 flags;
+};
+/* Flag set when the governor in use only allows one frequency.
+ * Disables scaling.
+ */
+#define SCHED_LOAD_FREQINVAR_SINGLEFREQ 0x01
+
+static struct cpufreq_extents freq_scale[CONFIG_NR_CPUS];
+#endif /* CONFIG_HMP_FREQUENCY_INVARIANT_SCALE */
+#endif /* CONFIG_HMP_VARIABLE_SCALE */
+
+/* We can represent the historical contribution to runnable average as the
* coefficients of a geometric series. To do this we sub-divide our runnable
* history into segments of approximately 1ms (1024us); label the segment that
* occurred N-ms ago p_N, with p_0 corresponding to the current period, e.g.
@@ -1230,13 +1328,24 @@ static u32 __compute_runnable_contrib(u64 n)
*/
static __always_inline int __update_entity_runnable_avg(u64 now,
struct sched_avg *sa,
- int runnable)
+ int runnable,
+ int running,
+ int cpu)
{
u64 delta, periods;
u32 runnable_contrib;
int delta_w, decayed = 0;
+#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
+ u64 scaled_delta;
+ u32 scaled_runnable_contrib;
+ int scaled_delta_w;
+ u32 curr_scale = 1024;
+#endif /* CONFIG_HMP_FREQUENCY_INVARIANT_SCALE */
delta = now - sa->last_runnable_update;
+#ifdef CONFIG_HMP_VARIABLE_SCALE
+ delta = hmp_variable_scale_convert(delta);
+#endif
/*
* This should only happen when time goes backwards, which it
* unfortunately does during sched clock init when we swap over to TSC.
@@ -1255,6 +1364,12 @@ static __always_inline int __update_entity_runnable_avg(u64 now,
return 0;
sa->last_runnable_update = now;
+#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
+ /* retrieve scale factor for load */
+ if (hmp_data.freqinvar_load_scale_enabled)
+ curr_scale = freq_scale[cpu].curr_scale;
+#endif /* CONFIG_HMP_FREQUENCY_INVARIANT_SCALE */
+
/* delta_w is the amount already accumulated against our next period */
delta_w = sa->runnable_avg_period % 1024;
if (delta + delta_w >= 1024) {
@@ -1267,8 +1382,20 @@ static __always_inline int __update_entity_runnable_avg(u64 now,
* period and accrue it.
*/
delta_w = 1024 - delta_w;
+ /* scale runnable time if necessary */
+#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
+ scaled_delta_w = (delta_w * curr_scale)
+ >> SCHED_FREQSCALE_SHIFT;
+ if (runnable)
+ sa->runnable_avg_sum += scaled_delta_w;
+ if (running)
+ sa->usage_avg_sum += scaled_delta_w;
+#else
if (runnable)
sa->runnable_avg_sum += delta_w;
+ if (running)
+ sa->usage_avg_sum += delta_w;
+#endif /* #ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE */
sa->runnable_avg_period += delta_w;
delta -= delta_w;
@@ -1276,22 +1403,49 @@ static __always_inline int __update_entity_runnable_avg(u64 now,
/* Figure out how many additional periods this update spans */
periods = delta / 1024;
delta %= 1024;
-
+ /* decay the load we have accumulated so far */
sa->runnable_avg_sum = decay_load(sa->runnable_avg_sum,
periods + 1);
sa->runnable_avg_period = decay_load(sa->runnable_avg_period,
periods + 1);
-
+ sa->usage_avg_sum = decay_load(sa->usage_avg_sum, periods + 1);
+ /* add the contribution from this period */
/* Efficiently calculate \sum (1..n_period) 1024*y^i */
runnable_contrib = __compute_runnable_contrib(periods);
+ /* Apply load scaling if necessary.
+ * Note that multiplying the whole series is same as
+ * multiplying all terms
+ */
+#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
+ scaled_runnable_contrib = (runnable_contrib * curr_scale)
+ >> SCHED_FREQSCALE_SHIFT;
+ if (runnable)
+ sa->runnable_avg_sum += scaled_runnable_contrib;
+ if (running)
+ sa->usage_avg_sum += scaled_runnable_contrib;
+#else
if (runnable)
sa->runnable_avg_sum += runnable_contrib;
+ if (running)
+ sa->usage_avg_sum += runnable_contrib;
+#endif /* CONFIG_HMP_FREQUENCY_INVARIANT_SCALE */
sa->runnable_avg_period += runnable_contrib;
}
/* Remainder of delta accrued against u_0` */
+ /* scale if necessary */
+#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
+ scaled_delta = ((delta * curr_scale) >> SCHED_FREQSCALE_SHIFT);
+ if (runnable)
+ sa->runnable_avg_sum += scaled_delta;
+ if (running)
+ sa->usage_avg_sum += scaled_delta;
+#else
if (runnable)
sa->runnable_avg_sum += delta;
+ if (running)
+ sa->usage_avg_sum += delta;
+#endif /* CONFIG_HMP_FREQUENCY_INVARIANT_SCALE */
sa->runnable_avg_period += delta;
return decayed;
@@ -1337,16 +1491,28 @@ static inline void __update_tg_runnable_avg(struct sched_avg *sa,
struct cfs_rq *cfs_rq)
{
struct task_group *tg = cfs_rq->tg;
- long contrib;
+ long contrib, usage_contrib;
/* The fraction of a cpu used by this cfs_rq */
contrib = div_u64(sa->runnable_avg_sum << NICE_0_SHIFT,
sa->runnable_avg_period + 1);
contrib -= cfs_rq->tg_runnable_contrib;
- if (abs(contrib) > cfs_rq->tg_runnable_contrib / 64) {
+ usage_contrib = div_u64(sa->usage_avg_sum << NICE_0_SHIFT,
+ sa->runnable_avg_period + 1);
+ usage_contrib -= cfs_rq->tg_usage_contrib;
+
+ /*
+ * contrib/usage at this point represent deltas, only update if they
+ * are substantive.
+ */
+ if ((abs(contrib) > cfs_rq->tg_runnable_contrib / 64) ||
+ (abs(usage_contrib) > cfs_rq->tg_usage_contrib / 64)) {
atomic_add(contrib, &tg->runnable_avg);
cfs_rq->tg_runnable_contrib += contrib;
+
+ atomic_add(usage_contrib, &tg->usage_avg);
+ cfs_rq->tg_usage_contrib += usage_contrib;
}
}
@@ -1407,6 +1573,11 @@ static inline void __update_task_entity_contrib(struct sched_entity *se)
contrib = se->avg.runnable_avg_sum * scale_load_down(se->load.weight);
contrib /= (se->avg.runnable_avg_period + 1);
se->avg.load_avg_contrib = scale_load(contrib);
+ trace_sched_task_load_contrib(task_of(se), se->avg.load_avg_contrib);
+ contrib = se->avg.runnable_avg_sum * scale_load_down(NICE_0_LOAD);
+ contrib /= (se->avg.runnable_avg_period + 1);
+ se->avg.load_avg_ratio = scale_load(contrib);
+ trace_sched_task_runnable_ratio(task_of(se), se->avg.load_avg_ratio);
}
/* Compute the current contribution to load_avg by se, return any delta */
@@ -1442,7 +1613,11 @@ static inline void update_entity_load_avg(struct sched_entity *se,
struct cfs_rq *cfs_rq = cfs_rq_of(se);
long contrib_delta;
u64 now;
+ int cpu = -1; /* not used in normal case */
+#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
+ cpu = cfs_rq->rq->cpu;
+#endif
/*
* For a group entity we need to use their owned cfs_rq_clock_task() in
* case they are the parent of a throttled hierarchy.
@@ -1452,7 +1627,8 @@ static inline void update_entity_load_avg(struct sched_entity *se,
else
now = cfs_rq_clock_task(group_cfs_rq(se));
- if (!__update_entity_runnable_avg(now, &se->avg, se->on_rq))
+ if (!__update_entity_runnable_avg(now, &se->avg, se->on_rq,
+ cfs_rq->curr == se, cpu))
return;
contrib_delta = __update_entity_load_avg_contrib(se);
@@ -1496,8 +1672,19 @@ static void update_cfs_rq_blocked_load(struct cfs_rq *cfs_rq, int force_update)
static inline void update_rq_runnable_avg(struct rq *rq, int runnable)
{
- __update_entity_runnable_avg(rq->clock_task, &rq->avg, runnable);
+ u32 contrib;
+ int cpu = -1; /* not used in normal case */
+
+#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
+ cpu = rq->cpu;
+#endif
+ __update_entity_runnable_avg(rq->clock_task, &rq->avg, runnable,
+ runnable, cpu);
__update_tg_runnable_avg(&rq->avg, &rq->cfs);
+ contrib = rq->avg.runnable_avg_sum * scale_load_down(1024);
+ contrib /= (rq->avg.runnable_avg_period + 1);
+ trace_sched_rq_runnable_ratio(cpu_of(rq), scale_load(contrib));
+ trace_sched_rq_runnable_load(cpu_of(rq), rq->cfs.runnable_load_avg);
}
/* Add the load generated by se into cfs_rq's child load-average */
@@ -1864,6 +2051,7 @@ set_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
*/
update_stats_wait_end(cfs_rq, se);
__dequeue_entity(cfs_rq, se);
+ update_entity_load_avg(se, 1);
}
update_stats_curr_start(cfs_rq, se);
@@ -3292,6 +3480,387 @@ done:
return target;
}
+#ifdef CONFIG_SCHED_HMP
+/*
+ * Heterogenous multiprocessor (HMP) optimizations
+ *
+ * The cpu types are distinguished using a list of hmp_domains
+ * which each represent one cpu type using a cpumask.
+ * The list is assumed ordered by compute capacity with the
+ * fastest domain first.
+ */
+DEFINE_PER_CPU(struct hmp_domain *, hmp_cpu_domain);
+
+extern void __init arch_get_hmp_domains(struct list_head *hmp_domains_list);
+
+/* Setup hmp_domains */
+static int __init hmp_cpu_mask_setup(void)
+{
+ char buf[64];
+ struct hmp_domain *domain;
+ struct list_head *pos;
+ int dc, cpu;
+
+ pr_debug("Initializing HMP scheduler:\n");
+
+ /* Initialize hmp_domains using platform code */
+ arch_get_hmp_domains(&hmp_domains);
+ if (list_empty(&hmp_domains)) {
+ pr_debug("HMP domain list is empty!\n");
+ return 0;
+ }
+
+ /* Print hmp_domains */
+ dc = 0;
+ list_for_each(pos, &hmp_domains) {
+ domain = list_entry(pos, struct hmp_domain, hmp_domains);
+ cpulist_scnprintf(buf, 64, &domain->cpus);
+ pr_debug(" HMP domain %d: %s\n", dc, buf);
+
+ for_each_cpu_mask(cpu, domain->cpus) {
+ per_cpu(hmp_cpu_domain, cpu) = domain;
+ }
+ dc++;
+ }
+
+ return 1;
+}
+
+/*
+ * Migration thresholds should be in the range [0..1023]
+ * hmp_up_threshold: min. load required for migrating tasks to a faster cpu
+ * hmp_down_threshold: max. load allowed for tasks migrating to a slower cpu
+ * The default values (512, 256) offer good responsiveness, but may need
+ * tweaking suit particular needs.
+ *
+ * hmp_up_prio: Only up migrate task with high priority (<hmp_up_prio)
+ * hmp_next_up_threshold: Delay before next up migration (1024 ~= 1 ms)
+ * hmp_next_down_threshold: Delay before next down migration (1024 ~= 1 ms)
+ */
+unsigned int hmp_up_threshold = 512;
+unsigned int hmp_down_threshold = 256;
+#ifdef CONFIG_SCHED_HMP_PRIO_FILTER
+unsigned int hmp_up_prio = NICE_TO_PRIO(CONFIG_SCHED_HMP_PRIO_FILTER_VAL);
+#endif
+unsigned int hmp_next_up_threshold = 4096;
+unsigned int hmp_next_down_threshold = 4096;
+
+static unsigned int hmp_up_migration(int cpu, struct sched_entity *se);
+static unsigned int hmp_down_migration(int cpu, struct sched_entity *se);
+
+/* Check if cpu is in fastest hmp_domain */
+static inline unsigned int hmp_cpu_is_fastest(int cpu)
+{
+ struct list_head *pos;
+
+ pos = &hmp_cpu_domain(cpu)->hmp_domains;
+ return pos == hmp_domains.next;
+}
+
+/* Check if cpu is in slowest hmp_domain */
+static inline unsigned int hmp_cpu_is_slowest(int cpu)
+{
+ struct list_head *pos;
+
+ pos = &hmp_cpu_domain(cpu)->hmp_domains;
+ return list_is_last(pos, &hmp_domains);
+}
+
+/* Next (slower) hmp_domain relative to cpu */
+static inline struct hmp_domain *hmp_slower_domain(int cpu)
+{
+ struct list_head *pos;
+
+ pos = &hmp_cpu_domain(cpu)->hmp_domains;
+ return list_entry(pos->next, struct hmp_domain, hmp_domains);
+}
+
+/* Previous (faster) hmp_domain relative to cpu */
+static inline struct hmp_domain *hmp_faster_domain(int cpu)
+{
+ struct list_head *pos;
+
+ pos = &hmp_cpu_domain(cpu)->hmp_domains;
+ return list_entry(pos->prev, struct hmp_domain, hmp_domains);
+}
+
+/*
+ * Selects a cpu in previous (faster) hmp_domain
+ * Note that cpumask_any_and() returns the first cpu in the cpumask
+ */
+static inline unsigned int hmp_select_faster_cpu(struct task_struct *tsk,
+ int cpu)
+{
+ return cpumask_any_and(&hmp_faster_domain(cpu)->cpus,
+ tsk_cpus_allowed(tsk));
+}
+
+/*
+ * Selects a cpu in next (slower) hmp_domain
+ * Note that cpumask_any_and() returns the first cpu in the cpumask
+ */
+static inline unsigned int hmp_select_slower_cpu(struct task_struct *tsk,
+ int cpu)
+{
+ return cpumask_any_and(&hmp_slower_domain(cpu)->cpus,
+ tsk_cpus_allowed(tsk));
+}
+
+static inline void hmp_next_up_delay(struct sched_entity *se, int cpu)
+{
+ struct cfs_rq *cfs_rq = &cpu_rq(cpu)->cfs;
+
+ se->avg.hmp_last_up_migration = cfs_rq_clock_task(cfs_rq);
+ se->avg.hmp_last_down_migration = 0;
+}
+
+static inline void hmp_next_down_delay(struct sched_entity *se, int cpu)
+{
+ struct cfs_rq *cfs_rq = &cpu_rq(cpu)->cfs;
+
+ se->avg.hmp_last_down_migration = cfs_rq_clock_task(cfs_rq);
+ se->avg.hmp_last_up_migration = 0;
+}
+
+#ifdef CONFIG_HMP_VARIABLE_SCALE
+/*
+ * Heterogenous multiprocessor (HMP) optimizations
+ *
+ * These functions allow to change the growing speed of the load_avg_ratio
+ * by default it goes from 0 to 0.5 in LOAD_AVG_PERIOD = 32ms
+ * This can now be changed with /sys/kernel/hmp/load_avg_period_ms.
+ *
+ * These functions also allow to change the up and down threshold of HMP
+ * using /sys/kernel/hmp/{up,down}_threshold.
+ * Both must be between 0 and 1023. The threshold that is compared
+ * to the load_avg_ratio is up_threshold/1024 and down_threshold/1024.
+ *
+ * For instance, if load_avg_period = 64 and up_threshold = 512, an idle
+ * task with a load of 0 will reach the threshold after 64ms of busy loop.
+ *
+ * Changing load_avg_periods_ms has the same effect than changing the
+ * default scaling factor Y=1002/1024 in the load_avg_ratio computation to
+ * (1002/1024.0)^(LOAD_AVG_PERIOD/load_avg_period_ms), but the last one
+ * could trigger overflows.
+ * For instance, with Y = 1023/1024 in __update_task_entity_contrib()
+ * "contrib = se->avg.runnable_avg_sum * scale_load_down(se->load.weight);"
+ * could be overflowed for a weight > 2^12 even is the load_avg_contrib
+ * should still be a 32bits result. This would not happen by multiplicating
+ * delta time by 1/22 and setting load_avg_period_ms = 706.
+ */
+
+/*
+ * By scaling the delta time it end-up increasing or decrease the
+ * growing speed of the per entity load_avg_ratio
+ * The scale factor hmp_data.multiplier is a fixed point
+ * number: (32-HMP_VARIABLE_SCALE_SHIFT).HMP_VARIABLE_SCALE_SHIFT
+ */
+static u64 hmp_variable_scale_convert(u64 delta)
+{
+ u64 high = delta >> 32ULL;
+ u64 low = delta & 0xffffffffULL;
+ low *= hmp_data.multiplier;
+ high *= hmp_data.multiplier;
+ return (low >> HMP_VARIABLE_SCALE_SHIFT)
+ + (high << (32ULL - HMP_VARIABLE_SCALE_SHIFT));
+}
+
+static ssize_t hmp_show(struct kobject *kobj,
+ struct attribute *attr, char *buf)
+{
+ ssize_t ret = 0;
+ struct hmp_global_attr *hmp_attr =
+ container_of(attr, struct hmp_global_attr, attr);
+ int temp = *(hmp_attr->value);
+ if (hmp_attr->to_sysfs != NULL)
+ temp = hmp_attr->to_sysfs(temp);
+ ret = sprintf(buf, "%d\n", temp);
+ return ret;
+}
+
+static ssize_t hmp_store(struct kobject *a, struct attribute *attr,
+ const char *buf, size_t count)
+{
+ int temp;
+ ssize_t ret = count;
+ struct hmp_global_attr *hmp_attr =
+ container_of(attr, struct hmp_global_attr, attr);
+ char *str = vmalloc(count + 1);
+ if (str == NULL)
+ return -ENOMEM;
+ memcpy(str, buf, count);
+ str[count] = 0;
+ if (sscanf(str, "%d", &temp) < 1)
+ ret = -EINVAL;
+ else {
+ if (hmp_attr->from_sysfs != NULL)
+ temp = hmp_attr->from_sysfs(temp);
+ if (temp < 0)
+ ret = -EINVAL;
+ else
+ *(hmp_attr->value) = temp;
+ }
+ vfree(str);
+ return ret;
+}
+
+static int hmp_period_tofrom_sysfs(int value)
+{
+ return (LOAD_AVG_PERIOD << HMP_VARIABLE_SCALE_SHIFT) / value;
+}
+
+/* max value for threshold is 1024 */
+static int hmp_theshold_from_sysfs(int value)
+{
+ if (value > 1024)
+ return -1;
+ return value;
+}
+#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
+/* freqinvar control is only 0,1 off/on */
+static int hmp_freqinvar_from_sysfs(int value)
+{
+ if (value < 0 || value > 1)
+ return -1;
+ return value;
+}
+#endif
+static void hmp_attr_add(
+ const char *name,
+ int *value,
+ int (*to_sysfs)(int),
+ int (*from_sysfs)(int))
+{
+ int i = 0;
+ while (hmp_data.attributes[i] != NULL) {
+ i++;
+ if (i >= HMP_DATA_SYSFS_MAX)
+ return;
+ }
+ hmp_data.attr[i].attr.mode = 0644;
+ hmp_data.attr[i].show = hmp_show;
+ hmp_data.attr[i].store = hmp_store;
+ hmp_data.attr[i].attr.name = name;
+ hmp_data.attr[i].value = value;
+ hmp_data.attr[i].to_sysfs = to_sysfs;
+ hmp_data.attr[i].from_sysfs = from_sysfs;
+ hmp_data.attributes[i] = &hmp_data.attr[i].attr;
+ hmp_data.attributes[i + 1] = NULL;
+}
+
+static int hmp_attr_init(void)
+{
+ int ret;
+ memset(&hmp_data, sizeof(hmp_data), 0);
+ /* by default load_avg_period_ms == LOAD_AVG_PERIOD
+ * meaning no change
+ */
+ hmp_data.multiplier = hmp_period_tofrom_sysfs(LOAD_AVG_PERIOD);
+
+ hmp_attr_add("load_avg_period_ms",
+ &hmp_data.multiplier,
+ hmp_period_tofrom_sysfs,
+ hmp_period_tofrom_sysfs);
+ hmp_attr_add("up_threshold",
+ &hmp_up_threshold,
+ NULL,
+ hmp_theshold_from_sysfs);
+ hmp_attr_add("down_threshold",
+ &hmp_down_threshold,
+ NULL,
+ hmp_theshold_from_sysfs);
+#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
+ /* default frequency-invariant scaling ON */
+ hmp_data.freqinvar_load_scale_enabled = 1;
+ hmp_attr_add("frequency_invariant_load_scale",
+ &hmp_data.freqinvar_load_scale_enabled,
+ NULL,
+ hmp_freqinvar_from_sysfs);
+#endif
+ hmp_data.attr_group.name = "hmp";
+ hmp_data.attr_group.attrs = hmp_data.attributes;
+ ret = sysfs_create_group(kernel_kobj,
+ &hmp_data.attr_group);
+ return 0;
+}
+late_initcall(hmp_attr_init);
+#endif /* CONFIG_HMP_VARIABLE_SCALE */
+
+static inline unsigned int hmp_domain_min_load(struct hmp_domain *hmpd,
+ int *min_cpu)
+{
+ int cpu;
+ int min_load = INT_MAX;
+ int min_cpu_temp = NR_CPUS;
+
+ for_each_cpu_mask(cpu, hmpd->cpus) {
+ if (cpu_rq(cpu)->cfs.tg_load_contrib < min_load) {
+ min_load = cpu_rq(cpu)->cfs.tg_load_contrib;
+ min_cpu_temp = cpu;
+ }
+ }
+
+ if (min_cpu)
+ *min_cpu = min_cpu_temp;
+
+ return min_load;
+}
+
+/*
+ * Calculate the task starvation
+ * This is the ratio of actually running time vs. runnable time.
+ * If the two are equal the task is getting the cpu time it needs or
+ * it is alone on the cpu and the cpu is fully utilized.
+ */
+static inline unsigned int hmp_task_starvation(struct sched_entity *se)
+{
+ u32 starvation;
+
+ starvation = se->avg.usage_avg_sum * scale_load_down(NICE_0_LOAD);
+ starvation /= (se->avg.runnable_avg_sum + 1);
+
+ return scale_load(starvation);
+}
+
+static inline unsigned int hmp_offload_down(int cpu, struct sched_entity *se)
+{
+ int min_usage;
+ int dest_cpu = NR_CPUS;
+
+ if (hmp_cpu_is_slowest(cpu))
+ return NR_CPUS;
+
+ /* Is the current domain fully loaded? */
+ /* load < ~94% */
+ min_usage = hmp_domain_min_load(hmp_cpu_domain(cpu), NULL);
+ if (min_usage < NICE_0_LOAD-64)
+ return NR_CPUS;
+
+ /* Is the cpu oversubscribed? */
+ /* load < ~194% */
+ if (cpu_rq(cpu)->cfs.tg_load_contrib < 2*NICE_0_LOAD-64)
+ return NR_CPUS;
+
+ /* Is the task alone on the cpu? */
+ if (cpu_rq(cpu)->cfs.nr_running < 2)
+ return NR_CPUS;
+
+ /* Is the task actually starving? */
+ if (hmp_task_starvation(se) > 768) /* <25% waiting */
+ return NR_CPUS;
+
+ /* Does the slower domain have spare cycles? */
+ min_usage = hmp_domain_min_load(hmp_slower_domain(cpu), &dest_cpu);
+ /* load > 50% */
+ if (min_usage > NICE_0_LOAD/2)
+ return NR_CPUS;
+
+ if (cpumask_test_cpu(dest_cpu, &hmp_slower_domain(cpu)->cpus))
+ return dest_cpu;
+ return NR_CPUS;
+}
+#endif /* CONFIG_SCHED_HMP */
+
/*
* sched_balance_self: balance the current task (running on cpu) in domains
* that have the 'flag' flag set. In practice, this is SD_BALANCE_FORK and
@@ -3390,6 +3959,24 @@ select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flags)
unlock:
rcu_read_unlock();
+#ifdef CONFIG_SCHED_HMP
+ if (hmp_up_migration(prev_cpu, &p->se)) {
+ new_cpu = hmp_select_faster_cpu(p, prev_cpu);
+ hmp_next_up_delay(&p->se, new_cpu);
+ trace_sched_hmp_migrate(p, new_cpu, 0);
+ return new_cpu;
+ }
+ if (hmp_down_migration(prev_cpu, &p->se)) {
+ new_cpu = hmp_select_slower_cpu(p, prev_cpu);
+ hmp_next_down_delay(&p->se, new_cpu);
+ trace_sched_hmp_migrate(p, new_cpu, 0);
+ return new_cpu;
+ }
+ /* Make sure that the task stays in its previous hmp domain */
+ if (!cpumask_test_cpu(new_cpu, &hmp_cpu_domain(prev_cpu)->cpus))
+ return prev_cpu;
+#endif
+
return new_cpu;
}
@@ -3916,7 +4503,6 @@ int can_migrate_task(struct task_struct *p, struct lb_env *env)
* 1) task is cache cold, or
* 2) too many balance attempts have failed.
*/
-
tsk_cache_hot = task_hot(p, env->src_rq->clock_task, env->sd);
if (!tsk_cache_hot ||
env->sd->nr_balance_failed > env->sd->cache_nice_tries) {
@@ -5650,6 +6236,286 @@ need_kick:
static void nohz_idle_balance(int this_cpu, enum cpu_idle_type idle) { }
#endif
+#ifdef CONFIG_SCHED_HMP
+/* Check if task should migrate to a faster cpu */
+static unsigned int hmp_up_migration(int cpu, struct sched_entity *se)
+{
+ struct task_struct *p = task_of(se);
+ struct cfs_rq *cfs_rq = &cpu_rq(cpu)->cfs;
+ u64 now;
+
+ if (hmp_cpu_is_fastest(cpu))
+ return 0;
+
+#ifdef CONFIG_SCHED_HMP_PRIO_FILTER
+ /* Filter by task priority */
+ if (p->prio >= hmp_up_prio)
+ return 0;
+#endif
+
+ /* Let the task load settle before doing another up migration */
+ now = cfs_rq_clock_task(cfs_rq);
+ if (((now - se->avg.hmp_last_up_migration) >> 10)
+ < hmp_next_up_threshold)
+ return 0;
+
+ if (se->avg.load_avg_ratio > hmp_up_threshold) {
+ /* Target domain load < ~94% */
+ if (hmp_domain_min_load(hmp_faster_domain(cpu), NULL)
+ > NICE_0_LOAD-64)
+ return 0;
+ if (cpumask_intersects(&hmp_faster_domain(cpu)->cpus,
+ tsk_cpus_allowed(p)))
+ return 1;
+ }
+ return 0;
+}
+
+/* Check if task should migrate to a slower cpu */
+static unsigned int hmp_down_migration(int cpu, struct sched_entity *se)
+{
+ struct task_struct *p = task_of(se);
+ struct cfs_rq *cfs_rq = &cpu_rq(cpu)->cfs;
+ u64 now;
+
+ if (hmp_cpu_is_slowest(cpu))
+ return 0;
+
+#ifdef CONFIG_SCHED_HMP_PRIO_FILTER
+ /* Filter by task priority */
+ if ((p->prio >= hmp_up_prio) &&
+ cpumask_intersects(&hmp_slower_domain(cpu)->cpus,
+ tsk_cpus_allowed(p))) {
+ return 1;
+ }
+#endif
+
+ /* Let the task load settle before doing another down migration */
+ now = cfs_rq_clock_task(cfs_rq);
+ if (((now - se->avg.hmp_last_down_migration) >> 10)
+ < hmp_next_down_threshold)
+ return 0;
+
+ if (cpumask_intersects(&hmp_slower_domain(cpu)->cpus,
+ tsk_cpus_allowed(p))
+ && se->avg.load_avg_ratio < hmp_down_threshold) {
+ return 1;
+ }
+ return 0;
+}
+
+/*
+ * hmp_can_migrate_task - may task p from runqueue rq be migrated to this_cpu?
+ * Ideally this function should be merged with can_migrate_task() to avoid
+ * redundant code.
+ */
+static int hmp_can_migrate_task(struct task_struct *p, struct lb_env *env)
+{
+ int tsk_cache_hot = 0;
+
+ /*
+ * We do not migrate tasks that are:
+ * 1) running (obviously), or
+ * 2) cannot be migrated to this CPU due to cpus_allowed
+ */
+ if (!cpumask_test_cpu(env->dst_cpu, tsk_cpus_allowed(p))) {
+ schedstat_inc(p, se.statistics.nr_failed_migrations_affine);
+ return 0;
+ }
+ env->flags &= ~LBF_ALL_PINNED;
+
+ if (task_running(env->src_rq, p)) {
+ schedstat_inc(p, se.statistics.nr_failed_migrations_running);
+ return 0;
+ }
+
+ /*
+ * Aggressive migration if:
+ * 1) task is cache cold, or
+ * 2) too many balance attempts have failed.
+ */
+
+ tsk_cache_hot = task_hot(p, env->src_rq->clock_task, env->sd);
+ if (!tsk_cache_hot ||
+ env->sd->nr_balance_failed > env->sd->cache_nice_tries) {
+#ifdef CONFIG_SCHEDSTATS
+ if (tsk_cache_hot) {
+ schedstat_inc(env->sd, lb_hot_gained[env->idle]);
+ schedstat_inc(p, se.statistics.nr_forced_migrations);
+ }
+#endif
+ return 1;
+ }
+
+ return 1;
+}
+
+/*
+ * move_specific_task tries to move a specific task.
+ * Returns 1 if successful and 0 otherwise.
+ * Called with both runqueues locked.
+ */
+static int move_specific_task(struct lb_env *env, struct task_struct *pm)
+{
+ struct task_struct *p, *n;
+
+ list_for_each_entry_safe(p, n, &env->src_rq->cfs_tasks, se.group_node) {
+ if (throttled_lb_pair(task_group(p), env->src_rq->cpu,
+ env->dst_cpu))
+ continue;
+
+ if (!hmp_can_migrate_task(p, env))
+ continue;
+ /* Check if we found the right task */
+ if (p != pm)
+ continue;
+
+ move_task(p, env);
+ /*
+ * Right now, this is only the third place move_task()
+ * is called, so we can safely collect move_task()
+ * stats here rather than inside move_task().
+ */
+ schedstat_inc(env->sd, lb_gained[env->idle]);
+ return 1;
+ }
+ return 0;
+}
+
+/*
+ * hmp_active_task_migration_cpu_stop is run by cpu stopper and used to
+ * migrate a specific task from one runqueue to another.
+ * hmp_force_up_migration uses this to push a currently running task
+ * off a runqueue.
+ * Based on active_load_balance_stop_cpu and can potentially be merged.
+ */
+static int hmp_active_task_migration_cpu_stop(void *data)
+{
+ struct rq *busiest_rq = data;
+ struct task_struct *p = busiest_rq->migrate_task;
+ int busiest_cpu = cpu_of(busiest_rq);
+ int target_cpu = busiest_rq->push_cpu;
+ struct rq *target_rq = cpu_rq(target_cpu);
+ struct sched_domain *sd;
+
+ raw_spin_lock_irq(&busiest_rq->lock);
+ /* make sure the requested cpu hasn't gone down in the meantime */
+ if (unlikely(busiest_cpu != smp_processor_id() ||
+ !busiest_rq->active_balance)) {
+ goto out_unlock;
+ }
+ /* Is there any task to move? */
+ if (busiest_rq->nr_running <= 1)
+ goto out_unlock;
+ /* Task has migrated meanwhile, abort forced migration */
+ if (task_rq(p) != busiest_rq)
+ goto out_unlock;
+ /*
+ * This condition is "impossible", if it occurs
+ * we need to fix it. Originally reported by
+ * Bjorn Helgaas on a 128-cpu setup.
+ */
+ BUG_ON(busiest_rq == target_rq);
+
+ /* move a task from busiest_rq to target_rq */
+ double_lock_balance(busiest_rq, target_rq);
+
+ /* Search for an sd spanning us and the target CPU. */
+ rcu_read_lock();
+ for_each_domain(target_cpu, sd) {
+ if (cpumask_test_cpu(busiest_cpu, sched_domain_span(sd)))
+ break;
+ }
+
+ if (likely(sd)) {
+ struct lb_env env = {
+ .sd = sd,
+ .dst_cpu = target_cpu,
+ .dst_rq = target_rq,
+ .src_cpu = busiest_rq->cpu,
+ .src_rq = busiest_rq,
+ .idle = CPU_IDLE,
+ };
+
+ schedstat_inc(sd, alb_count);
+
+ if (move_specific_task(&env, p))
+ schedstat_inc(sd, alb_pushed);
+ else
+ schedstat_inc(sd, alb_failed);
+ }
+ rcu_read_unlock();
+ double_unlock_balance(busiest_rq, target_rq);
+out_unlock:
+ busiest_rq->active_balance = 0;
+ raw_spin_unlock_irq(&busiest_rq->lock);
+ return 0;
+}
+
+static DEFINE_SPINLOCK(hmp_force_migration);
+
+/*
+ * hmp_force_up_migration checks runqueues for tasks that need to
+ * be actively migrated to a faster cpu.
+ */
+static void hmp_force_up_migration(int this_cpu)
+{
+ int cpu;
+ struct sched_entity *curr;
+ struct rq *target;
+ unsigned long flags;
+ unsigned int force;
+ struct task_struct *p;
+
+ if (!spin_trylock(&hmp_force_migration))
+ return;
+ for_each_online_cpu(cpu) {
+ force = 0;
+ target = cpu_rq(cpu);
+ raw_spin_lock_irqsave(&target->lock, flags);
+ curr = target->cfs.curr;
+ if (!curr || !entity_is_task(curr)) {
+ raw_spin_unlock_irqrestore(&target->lock, flags);
+ continue;
+ }
+ p = task_of(curr);
+ if (hmp_up_migration(cpu, curr)) {
+ if (!target->active_balance) {
+ target->active_balance = 1;
+ target->push_cpu = hmp_select_faster_cpu(p, cpu);
+ target->migrate_task = p;
+ force = 1;
+ trace_sched_hmp_migrate(p, target->push_cpu, 1);
+ hmp_next_up_delay(&p->se, target->push_cpu);
+ }
+ }
+ if (!force && !target->active_balance) {
+ /*
+ * For now we just check the currently running task.
+ * Selecting the lightest task for offloading will
+ * require extensive book keeping.
+ */
+ target->push_cpu = hmp_offload_down(cpu, curr);
+ if (target->push_cpu < NR_CPUS) {
+ target->active_balance = 1;
+ target->migrate_task = p;
+ force = 1;
+ trace_sched_hmp_migrate(p, target->push_cpu, 2);
+ hmp_next_down_delay(&p->se, target->push_cpu);
+ }
+ }
+ raw_spin_unlock_irqrestore(&target->lock, flags);
+ if (force)
+ stop_one_cpu_nowait(cpu_of(target),
+ hmp_active_task_migration_cpu_stop,
+ target, &target->active_balance_work);
+ }
+ spin_unlock(&hmp_force_migration);
+}
+#else
+static void hmp_force_up_migration(int this_cpu) { }
+#endif /* CONFIG_SCHED_HMP */
+
/*
* run_rebalance_domains is triggered when needed from the scheduler tick.
* Also triggered for nohz idle balancing (with nohz_balancing_kick set).
@@ -5661,6 +6527,8 @@ static void run_rebalance_domains(struct softirq_action *h)
enum cpu_idle_type idle = this_rq->idle_balance ?
CPU_IDLE : CPU_NOT_IDLE;
+ hmp_force_up_migration(this_cpu);
+
rebalance_domains(this_cpu, idle);
/*
@@ -6160,6 +7028,139 @@ __init void init_sched_fair_class(void)
zalloc_cpumask_var(&nohz.idle_cpus_mask, GFP_NOWAIT);
cpu_notifier(sched_ilb_notifier, 0);
#endif
+
+#ifdef CONFIG_SCHED_HMP
+ hmp_cpu_mask_setup();
+#endif
#endif /* SMP */
}
+
+#ifdef CONFIG_HMP_FREQUENCY_INVARIANT_SCALE
+static u32 cpufreq_calc_scale(u32 min, u32 max, u32 curr)
+{
+ u32 result = curr / max;
+ return result;
+}
+
+/* Called when the CPU Frequency is changed.
+ * Once for each CPU.
+ */
+static int cpufreq_callback(struct notifier_block *nb,
+ unsigned long val, void *data)
+{
+ struct cpufreq_freqs *freq = data;
+ int cpu = freq->cpu;
+ struct cpufreq_extents *extents;
+
+ if (freq->flags & CPUFREQ_CONST_LOOPS)
+ return NOTIFY_OK;
+
+ if (val != CPUFREQ_POSTCHANGE)
+ return NOTIFY_OK;
+
+ /* if dynamic load scale is disabled, set the load scale to 1.0 */
+ if (!hmp_data.freqinvar_load_scale_enabled) {
+ freq_scale[cpu].curr_scale = 1024;
+ return NOTIFY_OK;
+ }
+
+ extents = &freq_scale[cpu];
+ if (extents->flags & SCHED_LOAD_FREQINVAR_SINGLEFREQ) {
+ /* If our governor was recognised as a single-freq governor,
+ * use 1.0
+ */
+ extents->curr_scale = 1024;
+ } else {
+ extents->curr_scale = cpufreq_calc_scale(extents->min,
+ extents->max, freq->new);
+ }
+
+ return NOTIFY_OK;
+}
+
+/* Called when the CPUFreq governor is changed.
+ * Only called for the CPUs which are actually changed by the
+ * userspace.
+ */
+static int cpufreq_policy_callback(struct notifier_block *nb,
+ unsigned long event, void *data)
+{
+ struct cpufreq_policy *policy = data;
+ struct cpufreq_extents *extents;
+ int cpu, singleFreq = 0;
+ static const char performance_governor[] = "performance";
+ static const char powersave_governor[] = "powersave";
+
+ if (event == CPUFREQ_START)
+ return 0;
+
+ if (event != CPUFREQ_INCOMPATIBLE)
+ return 0;
+
+ /* CPUFreq governors do not accurately report the range of
+ * CPU Frequencies they will choose from.
+ * We recognise performance and powersave governors as
+ * single-frequency only.
+ */
+ if (!strncmp(policy->governor->name, performance_governor,
+ strlen(performance_governor)) ||
+ !strncmp(policy->governor->name, powersave_governor,
+ strlen(powersave_governor)))
+ singleFreq = 1;
+
+ /* Make sure that all CPUs impacted by this policy are
+ * updated since we will only get a notification when the
+ * user explicitly changes the policy on a CPU.
+ */
+ for_each_cpu(cpu, policy->cpus) {
+ extents = &freq_scale[cpu];
+ extents->max = policy->max >> SCHED_FREQSCALE_SHIFT;
+ extents->min = policy->min >> SCHED_FREQSCALE_SHIFT;
+ if (!hmp_data.freqinvar_load_scale_enabled) {
+ extents->curr_scale = 1024;
+ } else if (singleFreq) {
+ extents->flags |= SCHED_LOAD_FREQINVAR_SINGLEFREQ;
+ extents->curr_scale = 1024;
+ } else {
+ extents->flags &= ~SCHED_LOAD_FREQINVAR_SINGLEFREQ;
+ extents->curr_scale = cpufreq_calc_scale(extents->min,
+ extents->max, policy->cur);
+ }
+ }
+
+ return 0;
+}
+
+static struct notifier_block cpufreq_notifier = {
+ .notifier_call = cpufreq_callback,
+};
+static struct notifier_block cpufreq_policy_notifier = {
+ .notifier_call = cpufreq_policy_callback,
+};
+
+static int __init register_sched_cpufreq_notifier(void)
+{
+ int ret = 0;
+
+ /* init safe defaults since there are no policies at registration */
+ for (ret = 0; ret < CONFIG_NR_CPUS; ret++) {
+ /* safe defaults */
+ freq_scale[ret].max = 1024;
+ freq_scale[ret].min = 1024;
+ freq_scale[ret].curr_scale = 1024;
+ }
+
+ pr_info("sched: registering cpufreq notifiers for scale-invariant loads\n");
+ ret = cpufreq_register_notifier(&cpufreq_policy_notifier,
+ CPUFREQ_POLICY_NOTIFIER);
+
+ if (ret != -EINVAL)
+ ret = cpufreq_register_notifier(&cpufreq_notifier,
+ CPUFREQ_TRANSITION_NOTIFIER);
+
+ return ret;
+}
+
+core_initcall(register_sched_cpufreq_notifier);
+#endif /* CONFIG_HMP_FREQUENCY_INVARIANT_SCALE */
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index cc03cfdf469..5affd9cf0a0 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -115,7 +115,7 @@ struct task_group {
atomic_t load_weight;
atomic64_t load_avg;
- atomic_t runnable_avg;
+ atomic_t runnable_avg, usage_avg;
#endif
#ifdef CONFIG_RT_GROUP_SCHED
@@ -245,7 +245,7 @@ struct cfs_rq {
#endif /* CONFIG_FAIR_GROUP_SCHED */
/* These always depend on CONFIG_FAIR_GROUP_SCHED */
#ifdef CONFIG_FAIR_GROUP_SCHED
- u32 tg_runnable_contrib;
+ u32 tg_runnable_contrib, tg_usage_contrib;
u64 tg_load_contrib;
#endif /* CONFIG_FAIR_GROUP_SCHED */
@@ -427,6 +427,9 @@ struct rq {
int active_balance;
int push_cpu;
struct cpu_stop_work active_balance_work;
+#ifdef CONFIG_SCHED_HMP
+ struct task_struct *migrate_task;
+#endif
/* cpu of this runqueue: */
int cpu;
int online;
@@ -549,6 +552,12 @@ DECLARE_PER_CPU(int, sd_llc_id);
extern int group_balance_cpu(struct sched_group *sg);
+#ifdef CONFIG_SCHED_HMP
+static LIST_HEAD(hmp_domains);
+DECLARE_PER_CPU(struct hmp_domain *, hmp_cpu_domain);
+#define hmp_cpu_domain(cpu) (per_cpu(hmp_cpu_domain, (cpu)))
+#endif /* CONFIG_SCHED_HMP */
+
#endif /* CONFIG_SMP */
#include "stats.h"
diff --git a/linaro/configs/big-LITTLE-MP.conf b/linaro/configs/big-LITTLE-MP.conf
new file mode 100644
index 00000000000..8cc2be049a4
--- /dev/null
+++ b/linaro/configs/big-LITTLE-MP.conf
@@ -0,0 +1,13 @@
+CONFIG_CGROUPS=y
+CONFIG_CGROUP_SCHED=y
+CONFIG_FAIR_GROUP_SCHED=y
+CONFIG_NO_HZ=y
+CONFIG_SCHED_MC=y
+CONFIG_DISABLE_CPU_SCHED_DOMAIN_BALANCE=y
+CONFIG_SCHED_HMP=y
+CONFIG_HMP_FAST_CPU_MASK=""
+CONFIG_HMP_SLOW_CPU_MASK=""
+CONFIG_HMP_VARIABLE_SCALE=y
+CONFIG_HMP_FREQUENCY_INVARIANT_SCALE=y
+CONFIG_SCHED_HMP_PRIO_FILTER=y
+CONFIG_SCHED_HMP_PRIO_FILTER_VAL=5