Kernel/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2025-01-01 10:45:49 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Scheduler changes for v6.8:

Browse Source 
- Energy scheduling:
 
     - Consolidate how the max compute capacity is
       used in the scheduler and how we calculate
       the frequency for a level of utilization.
 
     - Rework interface between the scheduler and
       the schedutil governor
 
     - Simplify the util_est logic
 
  - Deadline scheduler:
 
     - Work more towards reducing SCHED_DEADLINE
       starvation of low priority tasks (e.g., SCHED_OTHER)
       tasks when higher priority tasks monopolize CPU
       cycles, via the introduction of 'deadline servers'
       (nested/2-level scheduling).
       "Fair servers" to make use of this facility are
       not introduced yet.
 
  - EEVDF:
 
     - Introduce O(1) fastpath for EEVDF task selection
 
  - NUMA balancing:
 
     - Tune the NUMA-balancing vma scanning logic some more,
       to better distribute the probability
       of a particular vma getting scanned.
 
  - Plus misc fixes, cleanups and updates.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmWcASMRHG1pbmdvQGtl
 cm5lbC5vcmcACgkQEnMQ0APhK1jLbg/+NOwF18M6klF1/3jUaV1PU09vRzYnnA7w
 oF7Tru7JLV+/vZK+rwI1zxzj5Nj3sVBQPIyp1embEHx7Z/QH8MIaIVpcSFsDDCYY
 Q8n6ZVRB+lKWEo5+Ti6JEJftDAWuLHXwFWDa57oWPuR0Tc736+zYHUfj7jdKk0RI
 nT/lnOT6hXU8q26O4QFrBrrhvCCxc4byo7buKPQfqie0bDA70ppIWkFQoQME6mvQ
 US9jvOyUipOiPV06DPwFvPDJUQBGq2VdJNk+5zCEtcqEfLREuo/Xq1Ww1x1BWaZI
 761532EuDo73iMK4IFZrvVmj1ioz957qbje11MSSkDdKj692xxjXyvnY0NBvZuho
 Ueog/jQ4D4I2qu7pPSCF8UfnI/Hw4Q+KJ89j3pcywRm4hmCTf9k3MGpAaVLVxH7G
 e5REZ5MSsFZi4Cs+zF87Of5KCKLhTr1qSetNtShinKahg06WZ+MZ8tW4jb52qy0j
 F8PMlvfBI3f7SOtA8s2P26mDGQ21YQehN2d5P+Fbwj/U3fjIlSTOyx6NwLpFwYaS
 Vf+fctchGFV1Sh7c2JjCh+ecYfXx3ghT/pvyPOImJtxtCKSRUQ8c26ApC1OsWfOE
 FdHv4f2dPqcyswCZzIv/2fyDXc9eaS2E05EMDNqVuMCGnzidzSs81n7hBioNMrnH
 ZgHK90TmEbw=
 =wTVh
 -----END PGP SIGNATURE-----

Merge tag 'sched-core-2024-01-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler updates from Ingo Molnar:
 "Energy scheduling:

   - Consolidate how the max compute capacity is used in the scheduler
     and how we calculate the frequency for a level of utilization.

   - Rework interface between the scheduler and the schedutil governor

   - Simplify the util_est logic

  Deadline scheduler:

   - Work more towards reducing SCHED_DEADLINE starvation of low
     priority tasks (e.g., SCHED_OTHER) tasks when higher priority tasks
     monopolize CPU cycles, via the introduction of 'deadline servers'
     (nested/2-level scheduling).

     "Fair servers" to make use of this facility are not introduced yet.

  EEVDF:

   - Introduce O(1) fastpath for EEVDF task selection

  NUMA balancing:

   - Tune the NUMA-balancing vma scanning logic some more, to better
     distribute the probability of a particular vma getting scanned.

  Plus misc fixes, cleanups and updates"

* tag 'sched-core-2024-01-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
  sched/fair: Fix tg->load when offlining a CPU
  sched/fair: Remove unused 'next_buddy_marked' local variable in check_preempt_wakeup_fair()
  sched/fair: Use all little CPUs for CPU-bound workloads
  sched/fair: Simplify util_est
  sched/fair: Remove SCHED_FEAT(UTIL_EST_FASTUP, true)
  arm64/amu: Use capacity_ref_freq() to set AMU ratio
  cpufreq/cppc: Set the frequency used for computing the capacity
  cpufreq/cppc: Move and rename cppc_cpufreq_{perf_to_khz|khz_to_perf}()
  energy_model: Use a fixed reference frequency
  cpufreq/schedutil: Use a fixed reference frequency
  cpufreq: Use the fixed and coherent frequency for scaling capacity
  sched/topology: Add a new arch_scale_freq_ref() method
  freezer,sched: Clean saved_state when restoring it during thaw
  sched/fair: Update min_vruntime for reweight_entity() correctly
  sched/doc: Update documentation after renames and synchronize Chinese version
  sched/cpufreq: Rework iowait boost
  sched/cpufreq: Rework schedutil governor performance estimation
  sched/pelt: Avoid underestimation of task utilization
  sched/timers: Explain why idle task schedules out on remote timer enqueue
  sched/cpuidle: Comment about timers requirements VS idle handler
  ...
This commit is contained in:
Linus Torvalds 2024-01-08 19:49:17 -08:00
commit bfe8eb3b85
32 changed files with 1054 additions and 800 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
Documentation/scheduler/sched-design-CFS.rst
View File

@ -180,7 +180,7 @@ This is the (partial) list of the hooks:
compat_yield sysctl is turned on; in that case, it places the scheduling
entity at the right-most end of the red-black tree.
- check_preempt_curr(...)
- wakeup_preempt(...)
This function checks if a task that entered the runnable state should
preempt the currently running task.
@ -189,10 +189,10 @@ This is the (partial) list of the hooks:
This function chooses the most appropriate task eligible to run next.
- set_curr_task(...)
- set_next_task(...)
This function is called when a task changes its scheduling class or changes
its task group.
This function is called when a task changes its scheduling class, changes
its task group or is scheduled.
- task_tick(...)

7
Documentation/scheduler/schedutil.rst
View File

@ -90,8 +90,8 @@ For more detail see:
- Documentation/scheduler/sched-capacity.rst:"1. CPU Capacity + 2. Task utilization"
UTIL_EST / UTIL_EST_FASTUP
==========================
UTIL_EST
========
Because periodic tasks have their averages decayed while they sleep, even
though when running their expected utilization will be the same, they suffer a
@ -99,8 +99,7 @@ though when running their expected utilization will be the same, they suffer a
To alleviate this (a default enabled option) UTIL_EST drives an Infinite
Impulse Response (IIR) EWMA with the 'running' value on dequeue -- when it is
highest. A further default enabled option UTIL_EST_FASTUP modifies the IIR
filter to instantly increase and only decay on decrease.
highest. UTIL_EST filters to instantly increase and only decay on decrease.
A further runqueue wide sum (of runnable tasks) is maintained of:

8
Documentation/translations/zh_CN/scheduler/sched-design-CFS.rst
View File

@ -80,7 +80,7 @@ p->se.vruntime。一旦p->se.vruntime变得足够大，其它的任务将成为
CFS使用纳秒粒度的计时，不依赖于任何jiffies或HZ的细节。因此CFS并不像之前的调度器那样
有“时间片”的概念，也没有任何启发式的设计。唯一可调的参数（你需要打开CONFIG_SCHED_DEBUG）是：
/sys/kernel/debug/sched/min_granularity_ns
/sys/kernel/debug/sched/base_slice_ns
它可以用来将调度器从“桌面”模式（也就是低时延）调节为“服务器”（也就是高批处理）模式。
它的默认设置是适合桌面的工作负载。SCHED_BATCH也被CFS调度器模块处理。
@ -147,7 +147,7 @@ array）。
这个函数的行为基本上是出队，紧接着入队，除非compat_yield sysctl被开启。在那种情况下，
它将调度实体放在红黑树的最右端。
- check_preempt_curr(...)
- wakeup_preempt(...)
这个函数检查进入可运行状态的任务能否抢占当前正在运行的任务。
@ -155,9 +155,9 @@ array）。
这个函数选择接下来最适合运行的任务。
- set_curr_task(...)
- set_next_task(...)
这个函数在任务改变调度类或改变任务组时被调用。
这个函数在任务改变调度类，改变任务组时，或者任务被调度时被调用。
- task_tick(...)

7
Documentation/translations/zh_CN/scheduler/schedutil.rst
View File

@ -89,16 +89,15 @@ r_cpu被定义为当前CPU的最高性能水平与系统中任何其它CPU的最
- Documentation/translations/zh_CN/scheduler/sched-capacity.rst:"1. CPU Capacity + 2. Task utilization"
UTIL_EST / UTIL_EST_FASTUP
==========================
UTIL_EST
========
由于周期性任务的平均数在睡眠时会衰减，而在运行时其预期利用率会和睡眠前相同，
因此它们在再次运行后会面临（DVFS）的上涨。
为了缓解这个问题，（一个默认使能的编译选项）UTIL_EST驱动一个无限脉冲响应
（Infinite Impulse Response，IIR）的EWMA，“运行”值在出队时是最高的。
另一个默认使能的编译选项UTIL_EST_FASTUP修改了IIR滤波器，使其允许立即增加，
仅在利用率下降时衰减。
UTIL_EST滤波使其在遇到更高值时立刻增加，而遇到低值时会缓慢衰减。
进一步，运行队列的（可运行任务的）利用率之和由下式计算：

1
arch/arm/include/asm/topology.h
View File

@ -13,6 +13,7 @@
#define arch_set_freq_scale topology_set_freq_scale
#define arch_scale_freq_capacity topology_get_freq_scale
#define arch_scale_freq_invariant topology_scale_freq_invariant
#define arch_scale_freq_ref topology_get_freq_ref
#endif
/* Replace task scheduler's default cpu-invariant accounting */

1
arch/arm64/include/asm/topology.h
View File

@ -23,6 +23,7 @@ void update_freq_counters_refs(void);
#define arch_set_freq_scale topology_set_freq_scale
#define arch_scale_freq_capacity topology_get_freq_scale
#define arch_scale_freq_invariant topology_scale_freq_invariant
#define arch_scale_freq_ref topology_get_freq_ref
#ifdef CONFIG_ACPI_CPPC_LIB
#define arch_init_invariance_cppc topology_init_cpu_capacity_cppc

26
arch/arm64/kernel/topology.c
View File

@ -82,7 +82,12 @@ int __init parse_acpi_topology(void)
#undef pr_fmt
#define pr_fmt(fmt) "AMU: " fmt
static DEFINE_PER_CPU_READ_MOSTLY(unsigned long, arch_max_freq_scale);
/*
* Ensure that amu_scale_freq_tick() will return SCHED_CAPACITY_SCALE until
* the CPU capacity and its associated frequency have been correctly
* initialized.
*/
static DEFINE_PER_CPU_READ_MOSTLY(unsigned long, arch_max_freq_scale) = 1UL << (2 * SCHED_CAPACITY_SHIFT);
static DEFINE_PER_CPU(u64, arch_const_cycles_prev);
static DEFINE_PER_CPU(u64, arch_core_cycles_prev);
static cpumask_var_t amu_fie_cpus;
@ -112,14 +117,14 @@ static inline bool freq_counters_valid(int cpu)
return true;
}
static int freq_inv_set_max_ratio(int cpu, u64 max_rate, u64 ref_rate)
void freq_inv_set_max_ratio(int cpu, u64 max_rate)
{
u64 ratio;
u64 ratio, ref_rate = arch_timer_get_rate();
if (unlikely(!max_rate || !ref_rate)) {
pr_debug("CPU%d: invalid maximum or reference frequency.\n",
WARN_ONCE(1, "CPU%d: invalid maximum or reference frequency.\n",
cpu);
return -EINVAL;
return;
}
/*
@ -139,12 +144,10 @@ static int freq_inv_set_max_ratio(int cpu, u64 max_rate, u64 ref_rate)
ratio = div64_u64(ratio, max_rate);
if (!ratio) {
WARN_ONCE(1, "Reference frequency too low.\n");
return -EINVAL;
return;
}
per_cpu(arch_max_freq_scale, cpu) = (unsigned long)ratio;
return 0;
WRITE_ONCE(per_cpu(arch_max_freq_scale, cpu), (unsigned long)ratio);
}
static void amu_scale_freq_tick(void)
@ -195,10 +198,7 @@ static void amu_fie_setup(const struct cpumask *cpus)
return;
for_each_cpu(cpu, cpus) {
if (!freq_counters_valid(cpu) ||
freq_inv_set_max_ratio(cpu,
cpufreq_get_hw_max_freq(cpu) * 1000ULL,
arch_timer_get_rate()))
if (!freq_counters_valid(cpu))
return;
}

1
arch/riscv/include/asm/topology.h
View File

@ -9,6 +9,7 @@
#define arch_set_freq_scale topology_set_freq_scale
#define arch_scale_freq_capacity topology_get_freq_scale
#define arch_scale_freq_invariant topology_scale_freq_invariant
#define arch_scale_freq_ref topology_get_freq_ref
/* Replace task scheduler's default cpu-invariant accounting */
#define arch_scale_cpu_capacity topology_get_cpu_scale

104
drivers/acpi/cppc_acpi.c
View File

@ -39,6 +39,9 @@
#include <linux/rwsem.h>
#include <linux/wait.h>
#include <linux/topology.h>
#include <linux/dmi.h>
#include <linux/units.h>
#include <asm/unaligned.h>
#include <acpi/cppc_acpi.h>
@ -1760,3 +1763,104 @@ unsigned int cppc_get_transition_latency(int cpu_num)
return latency_ns;
}
EXPORT_SYMBOL_GPL(cppc_get_transition_latency);
/* Minimum struct length needed for the DMI processor entry we want */
#define DMI_ENTRY_PROCESSOR_MIN_LENGTH 48
/* Offset in the DMI processor structure for the max frequency */
#define DMI_PROCESSOR_MAX_SPEED 0x14
/* Callback function used to retrieve the max frequency from DMI */
static void cppc_find_dmi_mhz(const struct dmi_header *dm, void *private)
{
const u8 *dmi_data = (const u8 *)dm;
u16 *mhz = (u16 *)private;
if (dm->type == DMI_ENTRY_PROCESSOR &&
dm->length >= DMI_ENTRY_PROCESSOR_MIN_LENGTH) {
u16 val = (u16)get_unaligned((const u16 *)
(dmi_data + DMI_PROCESSOR_MAX_SPEED));
*mhz = val > *mhz ? val : *mhz;
}
}
/* Look up the max frequency in DMI */
static u64 cppc_get_dmi_max_khz(void)
{
u16 mhz = 0;
dmi_walk(cppc_find_dmi_mhz, &mhz);
/*
* Real stupid fallback value, just in case there is no
* actual value set.
*/
mhz = mhz ? mhz : 1;
return KHZ_PER_MHZ * mhz;
}
/*
* If CPPC lowest_freq and nominal_freq registers are exposed then we can
* use them to convert perf to freq and vice versa. The conversion is
* extrapolated as an affine function passing by the 2 points:
* - (Low perf, Low freq)
* - (Nominal perf, Nominal freq)
*/
unsigned int cppc_perf_to_khz(struct cppc_perf_caps *caps, unsigned int perf)
{
s64 retval, offset = 0;
static u64 max_khz;
u64 mul, div;
if (caps->lowest_freq && caps->nominal_freq) {
mul = caps->nominal_freq - caps->lowest_freq;
mul *= KHZ_PER_MHZ;
div = caps->nominal_perf - caps->lowest_perf;
offset = caps->nominal_freq * KHZ_PER_MHZ -
div64_u64(caps->nominal_perf * mul, div);
} else {
if (!max_khz)
max_khz = cppc_get_dmi_max_khz();
mul = max_khz;
div = caps->highest_perf;
}
retval = offset + div64_u64(perf * mul, div);
if (retval >= 0)
return retval;
return 0;
}
EXPORT_SYMBOL_GPL(cppc_perf_to_khz);
unsigned int cppc_khz_to_perf(struct cppc_perf_caps *caps, unsigned int freq)
{
s64 retval, offset = 0;
static u64 max_khz;
u64 mul, div;
if (caps->lowest_freq && caps->nominal_freq) {
mul = caps->nominal_perf - caps->lowest_perf;
div = caps->nominal_freq - caps->lowest_freq;
/*
* We don't need to convert to kHz for computing offset and can
* directly use nominal_freq and lowest_freq as the div64_u64
* will remove the frequency unit.
*/
offset = caps->nominal_perf -
div64_u64(caps->nominal_freq * mul, div);
/* But we need it for computing the perf level. */
div *= KHZ_PER_MHZ;
} else {
if (!max_khz)
max_khz = cppc_get_dmi_max_khz();
mul = caps->highest_perf;
div = max_khz;
}
retval = offset + div64_u64(freq * mul, div);
if (retval >= 0)
return retval;
return 0;
}
EXPORT_SYMBOL_GPL(cppc_khz_to_perf);

56
drivers/base/arch_topology.c
View File

@ -19,6 +19,7 @@
#include <linux/init.h>
#include <linux/rcupdate.h>
#include <linux/sched.h>
#include <linux/units.h>
#define CREATE_TRACE_POINTS
#include <trace/events/thermal_pressure.h>
@ -26,7 +27,8 @@
static DEFINE_PER_CPU(struct scale_freq_data __rcu *, sft_data);
static struct cpumask scale_freq_counters_mask;
static bool scale_freq_invariant;
static DEFINE_PER_CPU(u32, freq_factor) = 1;
DEFINE_PER_CPU(unsigned long, capacity_freq_ref) = 1;
EXPORT_PER_CPU_SYMBOL_GPL(capacity_freq_ref);
static bool supports_scale_freq_counters(const struct cpumask *cpus)
{
@ -170,9 +172,9 @@ DEFINE_PER_CPU(unsigned long, thermal_pressure);
* operating on stale data when hot-plug is used for some CPUs. The
* @capped_freq reflects the currently allowed max CPUs frequency due to
* thermal capping. It might be also a boost frequency value, which is bigger
* than the internal 'freq_factor' max frequency. In such case the pressure
* value should simply be removed, since this is an indication that there is
* no thermal throttling. The @capped_freq must be provided in kHz.
* than the internal 'capacity_freq_ref' max frequency. In such case the
* pressure value should simply be removed, since this is an indication that
* there is no thermal throttling. The @capped_freq must be provided in kHz.
*/
void topology_update_thermal_pressure(const struct cpumask *cpus,
unsigned long capped_freq)
@ -183,10 +185,7 @@ void topology_update_thermal_pressure(const struct cpumask *cpus,
cpu = cpumask_first(cpus);
max_capacity = arch_scale_cpu_capacity(cpu);
max_freq = per_cpu(freq_factor, cpu);
/* Convert to MHz scale which is used in 'freq_factor' */
capped_freq /= 1000;
max_freq = arch_scale_freq_ref(cpu);
/*
* Handle properly the boost frequencies, which should simply clean
@ -279,13 +278,13 @@ void topology_normalize_cpu_scale(void)
capacity_scale = 1;
for_each_possible_cpu(cpu) {
capacity = raw_capacity[cpu] * per_cpu(freq_factor, cpu);
capacity = raw_capacity[cpu] * per_cpu(capacity_freq_ref, cpu);
capacity_scale = max(capacity, capacity_scale);
}
pr_debug("cpu_capacity: capacity_scale=%llu\n", capacity_scale);
for_each_possible_cpu(cpu) {
capacity = raw_capacity[cpu] * per_cpu(freq_factor, cpu);
capacity = raw_capacity[cpu] * per_cpu(capacity_freq_ref, cpu);
capacity = div64_u64(capacity << SCHED_CAPACITY_SHIFT,
capacity_scale);
topology_set_cpu_scale(cpu, capacity);
@ -321,15 +320,15 @@ bool __init topology_parse_cpu_capacity(struct device_node *cpu_node, int cpu)
cpu_node, raw_capacity[cpu]);
/*
* Update freq_factor for calculating early boot cpu capacities.
* Update capacity_freq_ref for calculating early boot CPU capacities.
* For non-clk CPU DVFS mechanism, there's no way to get the
* frequency value now, assuming they are running at the same
* frequency (by keeping the initial freq_factor value).
* frequency (by keeping the initial capacity_freq_ref value).
*/
cpu_clk = of_clk_get(cpu_node, 0);
if (!PTR_ERR_OR_ZERO(cpu_clk)) {
per_cpu(freq_factor, cpu) =
clk_get_rate(cpu_clk) / 1000;
per_cpu(capacity_freq_ref, cpu) =
clk_get_rate(cpu_clk) / HZ_PER_KHZ;
clk_put(cpu_clk);
}
} else {
@ -345,11 +344,16 @@ bool __init topology_parse_cpu_capacity(struct device_node *cpu_node, int cpu)
return !ret;
}
void __weak freq_inv_set_max_ratio(int cpu, u64 max_rate)
{
}
#ifdef CONFIG_ACPI_CPPC_LIB
#include <acpi/cppc_acpi.h>
void topology_init_cpu_capacity_cppc(void)
{
u64 capacity, capacity_scale = 0;
struct cppc_perf_caps perf_caps;
int cpu;
@ -366,6 +370,10 @@ void topology_init_cpu_capacity_cppc(void)
(perf_caps.highest_perf >= perf_caps.nominal_perf) &&
(perf_caps.highest_perf >= perf_caps.lowest_perf)) {
raw_capacity[cpu] = perf_caps.highest_perf;
capacity_scale = max_t(u64, capacity_scale, raw_capacity[cpu]);
per_cpu(capacity_freq_ref, cpu) = cppc_perf_to_khz(&perf_caps, raw_capacity[cpu]);
pr_debug("cpu_capacity: CPU%d cpu_capacity=%u (raw).\n",
cpu, raw_capacity[cpu]);
continue;
@ -376,7 +384,18 @@ void topology_init_cpu_capacity_cppc(void)
goto exit;
}
topology_normalize_cpu_scale();
for_each_possible_cpu(cpu) {
freq_inv_set_max_ratio(cpu,
per_cpu(capacity_freq_ref, cpu) * HZ_PER_KHZ);
capacity = raw_capacity[cpu];
capacity = div64_u64(capacity << SCHED_CAPACITY_SHIFT,
capacity_scale);
topology_set_cpu_scale(cpu, capacity);
pr_debug("cpu_capacity: CPU%d cpu_capacity=%lu\n",
cpu, topology_get_cpu_scale(cpu));
}
schedule_work(&update_topology_flags_work);
pr_debug("cpu_capacity: cpu_capacity initialization done\n");
@ -410,8 +429,11 @@ init_cpu_capacity_callback(struct notifier_block *nb,
cpumask_andnot(cpus_to_visit, cpus_to_visit, policy->related_cpus);
for_each_cpu(cpu, policy->related_cpus)
per_cpu(freq_factor, cpu) = policy->cpuinfo.max_freq / 1000;
for_each_cpu(cpu, policy->related_cpus) {
per_cpu(capacity_freq_ref, cpu) = policy->cpuinfo.max_freq;
freq_inv_set_max_ratio(cpu,
per_cpu(capacity_freq_ref, cpu) * HZ_PER_KHZ);
}
if (cpumask_empty(cpus_to_visit)) {
topology_normalize_cpu_scale();

139
drivers/cpufreq/cppc_cpufreq.c
View File

@ -16,7 +16,6 @@
#include <linux/delay.h>
#include <linux/cpu.h>
#include <linux/cpufreq.h>
#include <linux/dmi.h>
#include <linux/irq_work.h>
#include <linux/kthread.h>
#include <linux/time.h>
@ -27,12 +26,6 @@
#include <acpi/cppc_acpi.h>
/* Minimum struct length needed for the DMI processor entry we want */
#define DMI_ENTRY_PROCESSOR_MIN_LENGTH 48
/* Offset in the DMI processor structure for the max frequency */
#define DMI_PROCESSOR_MAX_SPEED 0x14
/*
* This list contains information parsed from per CPU ACPI _CPC and _PSD
* structures: e.g. the highest and lowest supported performance, capabilities,
@ -291,97 +284,9 @@ static inline void cppc_freq_invariance_exit(void)
}
#endif /* CONFIG_ACPI_CPPC_CPUFREQ_FIE */
/* Callback function used to retrieve the max frequency from DMI */
static void cppc_find_dmi_mhz(const struct dmi_header *dm, void *private)
{
const u8 *dmi_data = (const u8 *)dm;
u16 *mhz = (u16 *)private;
if (dm->type == DMI_ENTRY_PROCESSOR &&
dm->length >= DMI_ENTRY_PROCESSOR_MIN_LENGTH) {
u16 val = (u16)get_unaligned((const u16 *)
(dmi_data + DMI_PROCESSOR_MAX_SPEED));
*mhz = val > *mhz ? val : *mhz;
}
}
/* Look up the max frequency in DMI */
static u64 cppc_get_dmi_max_khz(void)
{
u16 mhz = 0;
dmi_walk(cppc_find_dmi_mhz, &mhz);
/*
* Real stupid fallback value, just in case there is no
* actual value set.
*/
mhz = mhz ? mhz : 1;
return (1000 * mhz);
}
/*
* If CPPC lowest_freq and nominal_freq registers are exposed then we can
* use them to convert perf to freq and vice versa. The conversion is
* extrapolated as an affine function passing by the 2 points:
* - (Low perf, Low freq)
* - (Nominal perf, Nominal perf)
*/
static unsigned int cppc_cpufreq_perf_to_khz(struct cppc_cpudata *cpu_data,
unsigned int perf)
{
struct cppc_perf_caps *caps = &cpu_data->perf_caps;
s64 retval, offset = 0;
static u64 max_khz;
u64 mul, div;
if (caps->lowest_freq && caps->nominal_freq) {
mul = caps->nominal_freq - caps->lowest_freq;
div = caps->nominal_perf - caps->lowest_perf;
offset = caps->nominal_freq - div64_u64(caps->nominal_perf * mul, div);
} else {
if (!max_khz)
max_khz = cppc_get_dmi_max_khz();
mul = max_khz;
div = caps->highest_perf;
}
retval = offset + div64_u64(perf * mul, div);
if (retval >= 0)
return retval;
return 0;
}
static unsigned int cppc_cpufreq_khz_to_perf(struct cppc_cpudata *cpu_data,
unsigned int freq)
{
struct cppc_perf_caps *caps = &cpu_data->perf_caps;
s64 retval, offset = 0;
static u64 max_khz;
u64 mul, div;
if (caps->lowest_freq && caps->nominal_freq) {
mul = caps->nominal_perf - caps->lowest_perf;
div = caps->nominal_freq - caps->lowest_freq;
offset = caps->nominal_perf - div64_u64(caps->nominal_freq * mul, div);
} else {
if (!max_khz)
max_khz = cppc_get_dmi_max_khz();
mul = caps->highest_perf;
div = max_khz;
}
retval = offset + div64_u64(freq * mul, div);
if (retval >= 0)
return retval;
return 0;
}
static int cppc_cpufreq_set_target(struct cpufreq_policy *policy,
unsigned int target_freq,
unsigned int relation)
{
struct cppc_cpudata *cpu_data = policy->driver_data;
unsigned int cpu = policy->cpu;
@ -389,7 +294,7 @@ static int cppc_cpufreq_set_target(struct cpufreq_policy *policy,
u32 desired_perf;
int ret = 0;
desired_perf = cppc_cpufreq_khz_to_perf(cpu_data, target_freq);
desired_perf = cppc_khz_to_perf(&cpu_data->perf_caps, target_freq);
/* Return if it is exactly the same perf */
if (desired_perf == cpu_data->perf_ctrls.desired_perf)
return ret;
@ -417,7 +322,7 @@ static unsigned int cppc_cpufreq_fast_switch(struct cpufreq_policy *policy,
u32 desired_perf;
int ret;
desired_perf = cppc_cpufreq_khz_to_perf(cpu_data, target_freq);
desired_perf = cppc_khz_to_perf(&cpu_data->perf_caps, target_freq);
cpu_data->perf_ctrls.desired_perf = desired_perf;
ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);
@ -530,7 +435,7 @@ static int cppc_get_cpu_power(struct device *cpu_dev,
min_step = min_cap / CPPC_EM_CAP_STEP;
max_step = max_cap / CPPC_EM_CAP_STEP;
perf_prev = cppc_cpufreq_khz_to_perf(cpu_data, *KHz);
perf_prev = cppc_khz_to_perf(perf_caps, *KHz);
step = perf_prev / perf_step;
if (step > max_step)
@ -550,8 +455,8 @@ static int cppc_get_cpu_power(struct device *cpu_dev,
perf = step * perf_step;
}
*KHz = cppc_cpufreq_perf_to_khz(cpu_data, perf);
perf_check = cppc_cpufreq_khz_to_perf(cpu_data, *KHz);
*KHz = cppc_perf_to_khz(perf_caps, perf);
perf_check = cppc_khz_to_perf(perf_caps, *KHz);
step_check = perf_check / perf_step;
/*
@ -561,8 +466,8 @@ static int cppc_get_cpu_power(struct device *cpu_dev,
*/
while ((*KHz == prev_freq) || (step_check != step)) {
perf++;
*KHz = cppc_cpufreq_perf_to_khz(cpu_data, perf);
perf_check = cppc_cpufreq_khz_to_perf(cpu_data, *KHz);
*KHz = cppc_perf_to_khz(perf_caps, perf);
perf_check = cppc_khz_to_perf(perf_caps, *KHz);
step_check = perf_check / perf_step;
}
@ -591,7 +496,7 @@ static int cppc_get_cpu_cost(struct device *cpu_dev, unsigned long KHz,
perf_caps = &cpu_data->perf_caps;
max_cap = arch_scale_cpu_capacity(cpu_dev->id);
perf_prev = cppc_cpufreq_khz_to_perf(cpu_data, KHz);
perf_prev = cppc_khz_to_perf(perf_caps, KHz);
perf_step = CPPC_EM_CAP_STEP * perf_caps->highest_perf / max_cap;
step = perf_prev / perf_step;
@ -679,10 +584,6 @@ static struct cppc_cpudata *cppc_cpufreq_get_cpu_data(unsigned int cpu)
goto free_mask;
}
/* Convert the lowest and nominal freq from MHz to KHz */
cpu_data->perf_caps.lowest_freq *= 1000;
cpu_data->perf_caps.nominal_freq *= 1000;
list_add(&cpu_data->node, &cpu_data_list);
return cpu_data;
@ -724,20 +625,16 @@ static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy)
* Set min to lowest nonlinear perf to avoid any efficiency penalty (see
* Section 8.4.7.1.1.5 of ACPI 6.1 spec)
*/
policy->min = cppc_cpufreq_perf_to_khz(cpu_data,
caps->lowest_nonlinear_perf);
policy->max = cppc_cpufreq_perf_to_khz(cpu_data,
caps->nominal_perf);
policy->min = cppc_perf_to_khz(caps, caps->lowest_nonlinear_perf);
policy->max = cppc_perf_to_khz(caps, caps->nominal_perf);
/*
* Set cpuinfo.min_freq to Lowest to make the full range of performance
* available if userspace wants to use any perf between lowest & lowest
* nonlinear perf
*/
policy->cpuinfo.min_freq = cppc_cpufreq_perf_to_khz(cpu_data,
caps->lowest_perf);
policy->cpuinfo.max_freq = cppc_cpufreq_perf_to_khz(cpu_data,
caps->nominal_perf);
policy->cpuinfo.min_freq = cppc_perf_to_khz(caps, caps->lowest_perf);
policy->cpuinfo.max_freq = cppc_perf_to_khz(caps, caps->nominal_perf);
policy->transition_delay_us = cppc_cpufreq_get_transition_delay_us(cpu);
policy->shared_type = cpu_data->shared_type;
@ -773,7 +670,7 @@ static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy)
boost_supported = true;
/* Set policy->cur to max now. The governors will adjust later. */
policy->cur = cppc_cpufreq_perf_to_khz(cpu_data, caps->highest_perf);
policy->cur = cppc_perf_to_khz(caps, caps->highest_perf);
cpu_data->perf_ctrls.desired_perf = caps->highest_perf;
ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls);
@ -863,7 +760,7 @@ static unsigned int cppc_cpufreq_get_rate(unsigned int cpu)
delivered_perf = cppc_perf_from_fbctrs(cpu_data, &fb_ctrs_t0,
&fb_ctrs_t1);
return cppc_cpufreq_perf_to_khz(cpu_data, delivered_perf);
return cppc_perf_to_khz(&cpu_data->perf_caps, delivered_perf);
}
static int cppc_cpufreq_set_boost(struct cpufreq_policy *policy, int state)
@ -878,11 +775,9 @@ static int cppc_cpufreq_set_boost(struct cpufreq_policy *policy, int state)
}
if (state)
policy->max = cppc_cpufreq_perf_to_khz(cpu_data,
caps->highest_perf);
policy->max = cppc_perf_to_khz(caps, caps->highest_perf);
else
policy->max = cppc_cpufreq_perf_to_khz(cpu_data,
caps->nominal_perf);
policy->max = cppc_perf_to_khz(caps, caps->nominal_perf);
policy->cpuinfo.max_freq = policy->max;
ret = freq_qos_update_request(policy->max_freq_req, policy->max);
@ -937,7 +832,7 @@ static unsigned int hisi_cppc_cpufreq_get_rate(unsigned int cpu)
if (ret < 0)
return -EIO;
return cppc_cpufreq_perf_to_khz(cpu_data, desired_perf);
return cppc_perf_to_khz(&cpu_data->perf_caps, desired_perf);
}
static void cppc_check_hisi_workaround(void)

4
drivers/cpufreq/cpufreq.c
View File

@ -454,7 +454,7 @@ void cpufreq_freq_transition_end(struct cpufreq_policy *policy,
arch_set_freq_scale(policy->related_cpus,
policy->cur,
policy->cpuinfo.max_freq);
arch_scale_freq_ref(policy->cpu));
spin_lock(&policy->transition_lock);
policy->transition_ongoing = false;
@ -2174,7 +2174,7 @@ unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy,
policy->cur = freq;
arch_set_freq_scale(policy->related_cpus, freq,
policy->cpuinfo.max_freq);
arch_scale_freq_ref(policy->cpu));
cpufreq_stats_record_transition(policy, freq);
if (trace_cpu_frequency_enabled()) {

2
include/acpi/cppc_acpi.h
View File

@ -144,6 +144,8 @@ extern int cppc_set_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls);
extern int cppc_set_enable(int cpu, bool enable);
extern int cppc_get_perf_caps(int cpu, struct cppc_perf_caps *caps);
extern bool cppc_perf_ctrs_in_pcc(void);
extern unsigned int cppc_perf_to_khz(struct cppc_perf_caps *caps, unsigned int perf);
extern unsigned int cppc_khz_to_perf(struct cppc_perf_caps *caps, unsigned int freq);
extern bool acpi_cpc_valid(void);
extern bool cppc_allow_fast_switch(void);
extern int acpi_get_psd_map(unsigned int cpu, struct cppc_cpudata *cpu_data);

8
include/linux/arch_topology.h
View File

@ -27,6 +27,13 @@ static inline unsigned long topology_get_cpu_scale(int cpu)
void topology_set_cpu_scale(unsigned int cpu, unsigned long capacity);
DECLARE_PER_CPU(unsigned long, capacity_freq_ref);
static inline unsigned long topology_get_freq_ref(int cpu)
{
return per_cpu(capacity_freq_ref, cpu);
}
DECLARE_PER_CPU(unsigned long, arch_freq_scale);
static inline unsigned long topology_get_freq_scale(int cpu)
@ -92,6 +99,7 @@ void update_siblings_masks(unsigned int cpu);
void remove_cpu_topology(unsigned int cpuid);
void reset_cpu_topology(void);
int parse_acpi_topology(void);
void freq_inv_set_max_ratio(int cpu, u64 max_rate);
#endif
#endif /* _LINUX_ARCH_TOPOLOGY_H_ */

1
include/linux/cpufreq.h
View File

@ -1203,6 +1203,7 @@ void arch_set_freq_scale(const struct cpumask *cpus,
{
}
#endif
/* the following are really really optional */
extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs;
extern struct freq_attr cpufreq_freq_attr_scaling_boost_freqs;

7
include/linux/energy_model.h
View File

@ -224,7 +224,7 @@ static inline unsigned long em_cpu_energy(struct em_perf_domain *pd,
unsigned long max_util, unsigned long sum_util,
unsigned long allowed_cpu_cap)
{
unsigned long freq, scale_cpu;
unsigned long freq, ref_freq, scale_cpu;
struct em_perf_state *ps;
int cpu;
@ -241,11 +241,10 @@ static inline unsigned long em_cpu_energy(struct em_perf_domain *pd,
*/
cpu = cpumask_first(to_cpumask(pd->cpus));
scale_cpu = arch_scale_cpu_capacity(cpu);
ps = &pd->table[pd->nr_perf_states - 1];
ref_freq = arch_scale_freq_ref(cpu);
max_util = map_util_perf(max_util);
max_util = min(max_util, allowed_cpu_cap);
freq = map_util_freq(max_util, ps->frequency, scale_cpu);
freq = map_util_freq(max_util, ref_freq, scale_cpu);
/*
* Find the lowest performance state of the Energy Model above the

3
include/linux/mm_types.h
View File

@ -600,6 +600,9 @@ struct vma_numab_state {
*/
unsigned long pids_active[2];
/* MM scan sequence ID when scan first started after VMA creation */
int start_scan_seq;
/*
* MM scan sequence ID when the VMA was last completely scanned.
* A VMA is not eligible for scanning if prev_scan_seq == numa_scan_seq

75
include/linux/sched.h
View File

@ -63,11 +63,13 @@ struct robust_list_head;
struct root_domain;
struct rq;
struct sched_attr;
struct sched_dl_entity;
struct seq_file;
struct sighand_struct;
struct signal_struct;
struct task_delay_info;
struct task_group;
struct task_struct;
struct user_event_mm;
/*
@ -413,42 +415,6 @@ struct load_weight {
u32 inv_weight;
};
/**
* struct util_est - Estimation utilization of FAIR tasks
* @enqueued: instantaneous estimated utilization of a task/cpu
* @ewma: the Exponential Weighted Moving Average (EWMA)
* utilization of a task
*
* Support data structure to track an Exponential Weighted Moving Average
* (EWMA) of a FAIR task's utilization. New samples are added to the moving
* average each time a task completes an activation. Sample's weight is chosen
* so that the EWMA will be relatively insensitive to transient changes to the
* task's workload.
*
* The enqueued attribute has a slightly different meaning for tasks and cpus:
* - task: the task's util_avg at last task dequeue time
* - cfs_rq: the sum of util_est.enqueued for each RUNNABLE task on that CPU
* Thus, the util_est.enqueued of a task represents the contribution on the
* estimated utilization of the CPU where that task is currently enqueued.
*
* Only for tasks we track a moving average of the past instantaneous
* estimated utilization. This allows to absorb sporadic drops in utilization
* of an otherwise almost periodic task.
*
* The UTIL_AVG_UNCHANGED flag is used to synchronize util_est with util_avg
* updates. When a task is dequeued, its util_est should not be updated if its
* util_avg has not been updated in the meantime.
* This information is mapped into the MSB bit of util_est.enqueued at dequeue
* time. Since max value of util_est.enqueued for a task is 1024 (PELT util_avg
* for a task) it is safe to use MSB.
*/
struct util_est {
unsigned int enqueued;
unsigned int ewma;
#define UTIL_EST_WEIGHT_SHIFT 2
#define UTIL_AVG_UNCHANGED 0x80000000
} __attribute__((__aligned__(sizeof(u64))));
/*
* The load/runnable/util_avg accumulates an infinite geometric series
* (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c).
@ -503,9 +469,20 @@ struct sched_avg {
unsigned long load_avg;
unsigned long runnable_avg;
unsigned long util_avg;
struct util_est util_est;
unsigned int util_est;
} ____cacheline_aligned;
/*
* The UTIL_AVG_UNCHANGED flag is used to synchronize util_est with util_avg
* updates. When a task is dequeued, its util_est should not be updated if its
* util_avg has not been updated in the meantime.
* This information is mapped into the MSB bit of util_est at dequeue time.
* Since max value of util_est for a task is 1024 (PELT util_avg for a task)
* it is safe to use MSB.
*/
#define UTIL_EST_WEIGHT_SHIFT 2
#define UTIL_AVG_UNCHANGED 0x80000000
struct sched_statistics {
#ifdef CONFIG_SCHEDSTATS
u64 wait_start;
@ -523,7 +500,7 @@ struct sched_statistics {
u64 block_max;
s64 sum_block_runtime;
u64 exec_max;
s64 exec_max;
u64 slice_max;
u64 nr_migrations_cold;
@ -553,7 +530,7 @@ struct sched_entity {
struct load_weight load;
struct rb_node run_node;
u64 deadline;
u64 min_deadline;
u64 min_vruntime;
struct list_head group_node;
unsigned int on_rq;
@ -607,6 +584,9 @@ struct sched_rt_entity {
#endif
} __randomize_layout;
typedef bool (*dl_server_has_tasks_f)(struct sched_dl_entity *);
typedef struct task_struct *(*dl_server_pick_f)(struct sched_dl_entity *);
struct sched_dl_entity {
struct rb_node rb_node;
@ -654,6 +634,7 @@ struct sched_dl_entity {
unsigned int dl_yielded : 1;
unsigned int dl_non_contending : 1;
unsigned int dl_overrun : 1;
unsigned int dl_server : 1;
/*
* Bandwidth enforcement timer. Each -deadline task has its
@ -668,7 +649,20 @@ struct sched_dl_entity {
* timer is needed to decrease the active utilization at the correct
* time.
*/
struct hrtimer inactive_timer;
struct hrtimer inactive_timer;
/*
* Bits for DL-server functionality. Also see the comment near
* dl_server_update().
*
* @rq the runqueue this server is for
*
* @server_has_tasks() returns true if @server_pick return a
* runnable task.
*/
struct rq *rq;
dl_server_has_tasks_f server_has_tasks;
dl_server_pick_f server_pick;
#ifdef CONFIG_RT_MUTEXES
/*
@ -795,6 +789,7 @@ struct task_struct {
struct sched_entity se;
struct sched_rt_entity rt;
struct sched_dl_entity dl;
struct sched_dl_entity *dl_server;
const struct sched_class *sched_class;
#ifdef CONFIG_SCHED_CORE

8
include/linux/sched/topology.h
View File

@ -279,6 +279,14 @@ void arch_update_thermal_pressure(const struct cpumask *cpus,
{ }
#endif
#ifndef arch_scale_freq_ref
static __always_inline
unsigned int arch_scale_freq_ref(int cpu)
{
return 0;
}
#endif
static inline int task_node(const struct task_struct *p)
{
return cpu_to_node(task_cpu(p));

15
include/trace/events/sched.h
View File

@ -493,33 +493,30 @@ DEFINE_EVENT_SCHEDSTAT(sched_stat_template, sched_stat_blocked,
*/
DECLARE_EVENT_CLASS(sched_stat_runtime,
TP_PROTO(struct task_struct *tsk, u64 runtime, u64 vruntime),
TP_PROTO(struct task_struct *tsk, u64 runtime),
TP_ARGS(tsk, __perf_count(runtime), vruntime),
TP_ARGS(tsk, __perf_count(runtime)),
TP_STRUCT__entry(
__array( char, comm, TASK_COMM_LEN )
__field( pid_t, pid )
__field( u64, runtime )
__field( u64, vruntime )
),
TP_fast_assign(
memcpy(__entry->comm, tsk->comm, TASK_COMM_LEN);
__entry->pid = tsk->pid;
__entry->runtime = runtime;
__entry->vruntime = vruntime;
),
TP_printk("comm=%s pid=%d runtime=%Lu [ns] vruntime=%Lu [ns]",
TP_printk("comm=%s pid=%d runtime=%Lu [ns]",
__entry->comm, __entry->pid,
(unsigned long long)__entry->runtime,
(unsigned long long)__entry->vruntime)
(unsigned long long)__entry->runtime)
);
DEFINE_EVENT(sched_stat_runtime, sched_stat_runtime,
TP_PROTO(struct task_struct *tsk, u64 runtime, u64 vruntime),
TP_ARGS(tsk, runtime, vruntime));
TP_PROTO(struct task_struct *tsk, u64 runtime),
TP_ARGS(tsk, runtime));
/*
* Tracepoint for showing priority inheritance modifying a tasks

1
kernel/freezer.c
View File

@ -187,6 +187,7 @@ static int __restore_freezer_state(struct task_struct *p, void *arg)
if (state != TASK_RUNNING) {
WRITE_ONCE(p->__state, state);
p->saved_state = TASK_RUNNING;
return 1;
}

140
kernel/sched/core.c
View File

@ -1131,6 +1131,28 @@ static void wake_up_idle_cpu(int cpu)
if (cpu == smp_processor_id())
return;
/*
* Set TIF_NEED_RESCHED and send an IPI if in the non-polling
* part of the idle loop. This forces an exit from the idle loop
* and a round trip to schedule(). Now this could be optimized
* because a simple new idle loop iteration is enough to
* re-evaluate the next tick. Provided some re-ordering of tick
* nohz functions that would need to follow TIF_NR_POLLING
* clearing:
*
* - On most archs, a simple fetch_or on ti::flags with a
* "0" value would be enough to know if an IPI needs to be sent.
*
* - x86 needs to perform a last need_resched() check between
* monitor and mwait which doesn't take timers into account.
* There a dedicated TIF_TIMER flag would be required to
* fetch_or here and be checked along with TIF_NEED_RESCHED
* before mwait().
*
* However, remote timer enqueue is not such a frequent event
* and testing of the above solutions didn't appear to report
* much benefits.
*/
if (set_nr_and_not_polling(rq->idle))
smp_send_reschedule(cpu);
else
@ -2124,12 +2146,14 @@ void activate_task(struct rq *rq, struct task_struct *p, int flags)
enqueue_task(rq, p, flags);
p->on_rq = TASK_ON_RQ_QUEUED;
WRITE_ONCE(p->on_rq, TASK_ON_RQ_QUEUED);
ASSERT_EXCLUSIVE_WRITER(p->on_rq);
}
void deactivate_task(struct rq *rq, struct task_struct *p, int flags)
{
p->on_rq = (flags & DEQUEUE_SLEEP) ? 0 : TASK_ON_RQ_MIGRATING;
WRITE_ONCE(p->on_rq, (flags & DEQUEUE_SLEEP) ? 0 : TASK_ON_RQ_MIGRATING);
ASSERT_EXCLUSIVE_WRITER(p->on_rq);
dequeue_task(rq, p, flags);
}
@ -3795,6 +3819,8 @@ ttwu_do_activate(struct rq *rq, struct task_struct *p, int wake_flags,
rq->idle_stamp = 0;
}
#endif
p->dl_server = NULL;
}
/*
@ -4509,10 +4535,7 @@ static void __sched_fork(unsigned long clone_flags, struct task_struct *p)
memset(&p->stats, 0, sizeof(p->stats));
#endif
RB_CLEAR_NODE(&p->dl.rb_node);
init_dl_task_timer(&p->dl);
init_dl_inactive_task_timer(&p->dl);
__dl_clear_params(p);
init_dl_entity(&p->dl);
INIT_LIST_HEAD(&p->rt.run_list);
p->rt.timeout = 0;
@ -6004,12 +6027,27 @@ __pick_next_task(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
p = pick_next_task_idle(rq);
}
/*
* This is the fast path; it cannot be a DL server pick;
* therefore even if @p == @prev, ->dl_server must be NULL.
*/
if (p->dl_server)
p->dl_server = NULL;
return p;
}
restart:
put_prev_task_balance(rq, prev, rf);
/*
* We've updated @prev and no longer need the server link, clear it.
* Must be done before ->pick_next_task() because that can (re)set
* ->dl_server.
*/
if (prev->dl_server)
prev->dl_server = NULL;
for_each_class(class) {
p = class->pick_next_task(rq);
if (p)
@ -7429,18 +7467,13 @@ int sched_core_idle_cpu(int cpu)
* required to meet deadlines.
*/
unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
enum cpu_util_type type,
struct task_struct *p)
unsigned long *min,
unsigned long *max)
{
unsigned long dl_util, util, irq, max;
unsigned long util, irq, scale;
struct rq *rq = cpu_rq(cpu);
max = arch_scale_cpu_capacity(cpu);
if (!uclamp_is_used() &&
type == FREQUENCY_UTIL && rt_rq_is_runnable(&rq->rt)) {
return max;
}
scale = arch_scale_cpu_capacity(cpu);
/*
* Early check to see if IRQ/steal time saturates the CPU, can be
@ -7448,45 +7481,49 @@ unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
* update_irq_load_avg().
*/
irq = cpu_util_irq(rq);
if (unlikely(irq >= max))
return max;
if (unlikely(irq >= scale)) {
if (min)
*min = scale;
if (max)
*max = scale;
return scale;
}
if (min) {
/*
* The minimum utilization returns the highest level between:
* - the computed DL bandwidth needed with the IRQ pressure which
* steals time to the deadline task.
* - The minimum performance requirement for CFS and/or RT.
*/
*min = max(irq + cpu_bw_dl(rq), uclamp_rq_get(rq, UCLAMP_MIN));
/*
* When an RT task is runnable and uclamp is not used, we must
* ensure that the task will run at maximum compute capacity.
*/
if (!uclamp_is_used() && rt_rq_is_runnable(&rq->rt))
*min = max(*min, scale);
}
/*
* Because the time spend on RT/DL tasks is visible as 'lost' time to
* CFS tasks and we use the same metric to track the effective
* utilization (PELT windows are synchronized) we can directly add them
* to obtain the CPU's actual utilization.
*
* CFS and RT utilization can be boosted or capped, depending on
* utilization clamp constraints requested by currently RUNNABLE
* tasks.
* When there are no CFS RUNNABLE tasks, clamps are released and
* frequency will be gracefully reduced with the utilization decay.
*/
util = util_cfs + cpu_util_rt(rq);
if (type == FREQUENCY_UTIL)
util = uclamp_rq_util_with(rq, util, p);
dl_util = cpu_util_dl(rq);
util += cpu_util_dl(rq);
/*
* For frequency selection we do not make cpu_util_dl() a permanent part
* of this sum because we want to use cpu_bw_dl() later on, but we need
* to check if the CFS+RT+DL sum is saturated (ie. no idle time) such
* that we select f_max when there is no idle time.
*
* NOTE: numerical errors or stop class might cause us to not quite hit
* saturation when we should -- something for later.
* The maximum hint is a soft bandwidth requirement, which can be lower
* than the actual utilization because of uclamp_max requirements.
*/
if (util + dl_util >= max)
return max;
if (max)
*max = min(scale, uclamp_rq_get(rq, UCLAMP_MAX));
/*
* OTOH, for energy computation we need the estimated running time, so
* include util_dl and ignore dl_bw.
*/
if (type == ENERGY_UTIL)
util += dl_util;
if (util >= scale)
return scale;
/*
* There is still idle time; further improve the number by using the
@ -7497,28 +7534,15 @@ unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
* U' = irq + --------- * U
* max
*/
util = scale_irq_capacity(util, irq, max);
util = scale_irq_capacity(util, irq, scale);
util += irq;
/*
* Bandwidth required by DEADLINE must always be granted while, for
* FAIR and RT, we use blocked utilization of IDLE CPUs as a mechanism
* to gracefully reduce the frequency when no tasks show up for longer
* periods of time.
*
* Ideally we would like to set bw_dl as min/guaranteed freq and util +
* bw_dl as requested freq. However, cpufreq is not yet ready for such
* an interface. So, we only do the latter for now.
*/
if (type == FREQUENCY_UTIL)
util += cpu_bw_dl(rq);
return min(max, util);
return min(scale, util);
}
unsigned long sched_cpu_util(int cpu)
{
return effective_cpu_util(cpu, cpu_util_cfs(cpu), ENERGY_UTIL, NULL);
return effective_cpu_util(cpu, cpu_util_cfs(cpu), NULL, NULL);
}
#endif /* CONFIG_SMP */

90
kernel/sched/cpufreq_schedutil.c
View File

@ -47,7 +47,7 @@ struct sugov_cpu {
u64 last_update;
unsigned long util;
unsigned long bw_dl;
unsigned long bw_min;
/* The field below is for single-CPU policies only: */
#ifdef CONFIG_NO_HZ_COMMON
@ -114,6 +114,28 @@ static void sugov_deferred_update(struct sugov_policy *sg_policy)
}
}
/**
* get_capacity_ref_freq - get the reference frequency that has been used to
* correlate frequency and compute capacity for a given cpufreq policy. We use
* the CPU managing it for the arch_scale_freq_ref() call in the function.
* @policy: the cpufreq policy of the CPU in question.
*
* Return: the reference CPU frequency to compute a capacity.
*/
static __always_inline
unsigned long get_capacity_ref_freq(struct cpufreq_policy *policy)
{
unsigned int freq = arch_scale_freq_ref(policy->cpu);
if (freq)
return freq;
if (arch_scale_freq_invariant())
return policy->cpuinfo.max_freq;
return policy->cur;
}
/**
* get_next_freq - Compute a new frequency for a given cpufreq policy.
* @sg_policy: schedutil policy object to compute the new frequency for.
@ -140,10 +162,9 @@ static unsigned int get_next_freq(struct sugov_policy *sg_policy,
unsigned long util, unsigned long max)
{
struct cpufreq_policy *policy = sg_policy->policy;
unsigned int freq = arch_scale_freq_invariant() ?
policy->cpuinfo.max_freq : policy->cur;
unsigned int freq;
util = map_util_perf(util);
freq = get_capacity_ref_freq(policy);
freq = map_util_freq(util, freq, max);
if (freq == sg_policy->cached_raw_freq && !sg_policy->need_freq_update)
@ -153,14 +174,31 @@ static unsigned int get_next_freq(struct sugov_policy *sg_policy,
return cpufreq_driver_resolve_freq(policy, freq);
}
static void sugov_get_util(struct sugov_cpu *sg_cpu)
unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual,
unsigned long min,
unsigned long max)
{
unsigned long util = cpu_util_cfs_boost(sg_cpu->cpu);
struct rq *rq = cpu_rq(sg_cpu->cpu);
/* Add dvfs headroom to actual utilization */
actual = map_util_perf(actual);
/* Actually we don't need to target the max performance */
if (actual < max)
max = actual;
sg_cpu->bw_dl = cpu_bw_dl(rq);
sg_cpu->util = effective_cpu_util(sg_cpu->cpu, util,
FREQUENCY_UTIL, NULL);
/*
* Ensure at least minimum performance while providing more compute
* capacity when possible.
*/
return max(min, max);
}
static void sugov_get_util(struct sugov_cpu *sg_cpu, unsigned long boost)
{
unsigned long min, max, util = cpu_util_cfs_boost(sg_cpu->cpu);
util = effective_cpu_util(sg_cpu->cpu, util, &min, &max);
util = max(util, boost);
sg_cpu->bw_min = min;
sg_cpu->util = sugov_effective_cpu_perf(sg_cpu->cpu, util, min, max);
}
/**
@ -251,18 +289,16 @@ static void sugov_iowait_boost(struct sugov_cpu *sg_cpu, u64 time,
* This mechanism is designed to boost high frequently IO waiting tasks, while
* being more conservative on tasks which does sporadic IO operations.
*/
static void sugov_iowait_apply(struct sugov_cpu *sg_cpu, u64 time,
static unsigned long sugov_iowait_apply(struct sugov_cpu *sg_cpu, u64 time,
unsigned long max_cap)
{
unsigned long boost;
/* No boost currently required */
if (!sg_cpu->iowait_boost)
return;
return 0;
/* Reset boost if the CPU appears to have been idle enough */
if (sugov_iowait_reset(sg_cpu, time, false))
return;
return 0;
if (!sg_cpu->iowait_boost_pending) {
/*
@ -271,7 +307,7 @@ static void sugov_iowait_apply(struct sugov_cpu *sg_cpu, u64 time,
sg_cpu->iowait_boost >>= 1;
if (sg_cpu->iowait_boost < IOWAIT_BOOST_MIN) {
sg_cpu->iowait_boost = 0;
return;
return 0;
}
}
@ -281,10 +317,7 @@ static void sugov_iowait_apply(struct sugov_cpu *sg_cpu, u64 time,
* sg_cpu->util is already in capacity scale; convert iowait_boost
* into the same scale so we can compare.
*/
boost = (sg_cpu->iowait_boost * max_cap) >> SCHED_CAPACITY_SHIFT;
boost = uclamp_rq_util_with(cpu_rq(sg_cpu->cpu), boost, NULL);
if (sg_cpu->util < boost)
sg_cpu->util = boost;
return (sg_cpu->iowait_boost * max_cap) >> SCHED_CAPACITY_SHIFT;
}
#ifdef CONFIG_NO_HZ_COMMON
@ -306,7 +339,7 @@ static inline bool sugov_cpu_is_busy(struct sugov_cpu *sg_cpu) { return false; }
*/
static inline void ignore_dl_rate_limit(struct sugov_cpu *sg_cpu)
{
if (cpu_bw_dl(cpu_rq(sg_cpu->cpu)) > sg_cpu->bw_dl)
if (cpu_bw_dl(cpu_rq(sg_cpu->cpu)) > sg_cpu->bw_min)
sg_cpu->sg_policy->limits_changed = true;
}
@ -314,6 +347,8 @@ static inline bool sugov_update_single_common(struct sugov_cpu *sg_cpu,
u64 time, unsigned long max_cap,
unsigned int flags)
{
unsigned long boost;
sugov_iowait_boost(sg_cpu, time, flags);
sg_cpu->last_update = time;
@ -322,8 +357,8 @@ static inline bool sugov_update_single_common(struct sugov_cpu *sg_cpu,
if (!sugov_should_update_freq(sg_cpu->sg_policy, time))
return false;
sugov_get_util(sg_cpu);
sugov_iowait_apply(sg_cpu, time, max_cap);
boost = sugov_iowait_apply(sg_cpu, time, max_cap);
sugov_get_util(sg_cpu, boost);
return true;
}
@ -407,8 +442,8 @@ static void sugov_update_single_perf(struct update_util_data *hook, u64 time,
sugov_cpu_is_busy(sg_cpu) && sg_cpu->util < prev_util)
sg_cpu->util = prev_util;
cpufreq_driver_adjust_perf(sg_cpu->cpu, map_util_perf(sg_cpu->bw_dl),
map_util_perf(sg_cpu->util), max_cap);
cpufreq_driver_adjust_perf(sg_cpu->cpu, sg_cpu->bw_min,
sg_cpu->util, max_cap);
sg_cpu->sg_policy->last_freq_update_time = time;
}
@ -424,9 +459,10 @@ static unsigned int sugov_next_freq_shared(struct sugov_cpu *sg_cpu, u64 time)
for_each_cpu(j, policy->cpus) {
struct sugov_cpu *j_sg_cpu = &per_cpu(sugov_cpu, j);
unsigned long boost;
sugov_get_util(j_sg_cpu);
sugov_iowait_apply(j_sg_cpu, time, max_cap);
boost = sugov_iowait_apply(j_sg_cpu, time, max_cap);
sugov_get_util(j_sg_cpu, boost);
util = max(j_sg_cpu->util, util);
}

477
kernel/sched/deadline.c
View File

@ -54,8 +54,14 @@ static int __init sched_dl_sysctl_init(void)
late_initcall(sched_dl_sysctl_init);
#endif
static bool dl_server(struct sched_dl_entity *dl_se)
{
return dl_se->dl_server;
}
static inline struct task_struct *dl_task_of(struct sched_dl_entity *dl_se)
{
BUG_ON(dl_server(dl_se));
return container_of(dl_se, struct task_struct, dl);
}
@ -64,12 +70,19 @@ static inline struct rq *rq_of_dl_rq(struct dl_rq *dl_rq)
return container_of(dl_rq, struct rq, dl);
}
static inline struct rq *rq_of_dl_se(struct sched_dl_entity *dl_se)
{
struct rq *rq = dl_se->rq;
if (!dl_server(dl_se))
rq = task_rq(dl_task_of(dl_se));
return rq;
}
static inline struct dl_rq *dl_rq_of_se(struct sched_dl_entity *dl_se)
{
struct task_struct *p = dl_task_of(dl_se);
struct rq *rq = task_rq(p);
return &rq->dl;
return &rq_of_dl_se(dl_se)->dl;
}
static inline int on_dl_rq(struct sched_dl_entity *dl_se)
@ -335,6 +348,8 @@ static void dl_change_utilization(struct task_struct *p, u64 new_bw)
__add_rq_bw(new_bw, &rq->dl);
}
static void __dl_clear_params(struct sched_dl_entity *dl_se);
/*
* The utilization of a task cannot be immediately removed from
* the rq active utilization (running_bw) when the task blocks.
@ -389,12 +404,11 @@ static void dl_change_utilization(struct task_struct *p, u64 new_bw)
* up, and checks if the task is still in the "ACTIVE non contending"
* state or not (in the second case, it updates running_bw).
*/
static void task_non_contending(struct task_struct *p)
static void task_non_contending(struct sched_dl_entity *dl_se)
{
struct sched_dl_entity *dl_se = &p->dl;
struct hrtimer *timer = &dl_se->inactive_timer;
struct dl_rq *dl_rq = dl_rq_of_se(dl_se);
struct rq *rq = rq_of_dl_rq(dl_rq);
struct rq *rq = rq_of_dl_se(dl_se);
struct dl_rq *dl_rq = &rq->dl;
s64 zerolag_time;
/*
@ -424,24 +438,33 @@ static void task_non_contending(struct task_struct *p)
* utilization now, instead of starting a timer
*/
if ((zerolag_time < 0) || hrtimer_active(&dl_se->inactive_timer)) {
if (dl_task(p))
if (dl_server(dl_se)) {
sub_running_bw(dl_se, dl_rq);
if (!dl_task(p) || READ_ONCE(p->__state) == TASK_DEAD) {
struct dl_bw *dl_b = dl_bw_of(task_cpu(p));
} else {
struct task_struct *p = dl_task_of(dl_se);
if (READ_ONCE(p->__state) == TASK_DEAD)
sub_rq_bw(&p->dl, &rq->dl);
raw_spin_lock(&dl_b->lock);
__dl_sub(dl_b, p->dl.dl_bw, dl_bw_cpus(task_cpu(p)));
raw_spin_unlock(&dl_b->lock);
__dl_clear_params(p);
if (dl_task(p))
sub_running_bw(dl_se, dl_rq);
if (!dl_task(p) || READ_ONCE(p->__state) == TASK_DEAD) {
struct dl_bw *dl_b = dl_bw_of(task_cpu(p));
if (READ_ONCE(p->__state) == TASK_DEAD)
sub_rq_bw(dl_se, &rq->dl);
raw_spin_lock(&dl_b->lock);
__dl_sub(dl_b, dl_se->dl_bw, dl_bw_cpus(task_cpu(p)));
raw_spin_unlock(&dl_b->lock);
__dl_clear_params(dl_se);
}
}
return;
}
dl_se->dl_non_contending = 1;
get_task_struct(p);
if (!dl_server(dl_se))
get_task_struct(dl_task_of(dl_se));
hrtimer_start(timer, ns_to_ktime(zerolag_time), HRTIMER_MODE_REL_HARD);
}
@ -468,8 +491,10 @@ static void task_contending(struct sched_dl_entity *dl_se, int flags)
* will not touch the rq's active utilization,
* so we are still safe.
*/
if (hrtimer_try_to_cancel(&dl_se->inactive_timer) == 1)
put_task_struct(dl_task_of(dl_se));
if (hrtimer_try_to_cancel(&dl_se->inactive_timer) == 1) {
if (!dl_server(dl_se))
put_task_struct(dl_task_of(dl_se));
}
} else {
/*
* Since "dl_non_contending" is not set, the
@ -482,10 +507,8 @@ static void task_contending(struct sched_dl_entity *dl_se, int flags)
}
}
static inline int is_leftmost(struct task_struct *p, struct dl_rq *dl_rq)
static inline int is_leftmost(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq)
{
struct sched_dl_entity *dl_se = &p->dl;
return rb_first_cached(&dl_rq->root) == &dl_se->rb_node;
}
@ -737,8 +760,10 @@ static inline void deadline_queue_pull_task(struct rq *rq)
}
#endif /* CONFIG_SMP */
static void
enqueue_dl_entity(struct sched_dl_entity *dl_se, int flags);
static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags);
static void __dequeue_task_dl(struct rq *rq, struct task_struct *p, int flags);
static void dequeue_dl_entity(struct sched_dl_entity *dl_se, int flags);
static void wakeup_preempt_dl(struct rq *rq, struct task_struct *p, int flags);
static inline void replenish_dl_new_period(struct sched_dl_entity *dl_se,
@ -986,8 +1011,7 @@ static inline bool dl_is_implicit(struct sched_dl_entity *dl_se)
*/
static void update_dl_entity(struct sched_dl_entity *dl_se)
{
struct dl_rq *dl_rq = dl_rq_of_se(dl_se);
struct rq *rq = rq_of_dl_rq(dl_rq);
struct rq *rq = rq_of_dl_se(dl_se);
if (dl_time_before(dl_se->deadline, rq_clock(rq)) ||
dl_entity_overflow(dl_se, rq_clock(rq))) {
@ -1018,11 +1042,11 @@ static inline u64 dl_next_period(struct sched_dl_entity *dl_se)
* actually started or not (i.e., the replenishment instant is in
* the future or in the past).
*/
static int start_dl_timer(struct task_struct *p)
static int start_dl_timer(struct sched_dl_entity *dl_se)
{
struct sched_dl_entity *dl_se = &p->dl;
struct hrtimer *timer = &dl_se->dl_timer;
struct rq *rq = task_rq(p);
struct dl_rq *dl_rq = dl_rq_of_se(dl_se);
struct rq *rq = rq_of_dl_rq(dl_rq);
ktime_t now, act;
s64 delta;
@ -1056,13 +1080,33 @@ static int start_dl_timer(struct task_struct *p)
* and observe our state.
*/
if (!hrtimer_is_queued(timer)) {
get_task_struct(p);
if (!dl_server(dl_se))
get_task_struct(dl_task_of(dl_se));
hrtimer_start(timer, act, HRTIMER_MODE_ABS_HARD);
}
return 1;
}
static void __push_dl_task(struct rq *rq, struct rq_flags *rf)
{
#ifdef CONFIG_SMP
/*
* Queueing this task back might have overloaded rq, check if we need
* to kick someone away.
*/
if (has_pushable_dl_tasks(rq)) {
/*
* Nothing relies on rq->lock after this, so its safe to drop
* rq->lock.
*/
rq_unpin_lock(rq, rf);
push_dl_task(rq);
rq_repin_lock(rq, rf);
}
#endif
}
/*
* This is the bandwidth enforcement timer callback. If here, we know
* a task is not on its dl_rq, since the fact that the timer was running
@ -1081,10 +1125,34 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer)
struct sched_dl_entity *dl_se = container_of(timer,
struct sched_dl_entity,
dl_timer);
struct task_struct *p = dl_task_of(dl_se);
struct task_struct *p;
struct rq_flags rf;
struct rq *rq;
if (dl_server(dl_se)) {
struct rq *rq = rq_of_dl_se(dl_se);
struct rq_flags rf;
rq_lock(rq, &rf);
if (dl_se->dl_throttled) {
sched_clock_tick();
update_rq_clock(rq);
if (dl_se->server_has_tasks(dl_se)) {
enqueue_dl_entity(dl_se, ENQUEUE_REPLENISH);
resched_curr(rq);
__push_dl_task(rq, &rf);
} else {
replenish_dl_entity(dl_se);
}
}
rq_unlock(rq, &rf);
return HRTIMER_NORESTART;
}
p = dl_task_of(dl_se);
rq = task_rq_lock(p, &rf);
/*
@ -1155,21 +1223,7 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer)
else
resched_curr(rq);
#ifdef CONFIG_SMP
/*
* Queueing this task back might have overloaded rq, check if we need
* to kick someone away.
*/
if (has_pushable_dl_tasks(rq)) {
/*
* Nothing relies on rq->lock after this, so its safe to drop
* rq->lock.
*/
rq_unpin_lock(rq, &rf);
push_dl_task(rq);
rq_repin_lock(rq, &rf);
}
#endif
__push_dl_task(rq, &rf);
unlock:
task_rq_unlock(rq, p, &rf);
@ -1183,7 +1237,7 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer)
return HRTIMER_NORESTART;
}
void init_dl_task_timer(struct sched_dl_entity *dl_se)
static void init_dl_task_timer(struct sched_dl_entity *dl_se)
{
struct hrtimer *timer = &dl_se->dl_timer;
@ -1211,12 +1265,11 @@ void init_dl_task_timer(struct sched_dl_entity *dl_se)
*/
static inline void dl_check_constrained_dl(struct sched_dl_entity *dl_se)
{
struct task_struct *p = dl_task_of(dl_se);
struct rq *rq = rq_of_dl_rq(dl_rq_of_se(dl_se));
struct rq *rq = rq_of_dl_se(dl_se);
if (dl_time_before(dl_se->deadline, rq_clock(rq)) &&
dl_time_before(rq_clock(rq), dl_next_period(dl_se))) {
if (unlikely(is_dl_boosted(dl_se) || !start_dl_timer(p)))
if (unlikely(is_dl_boosted(dl_se) || !start_dl_timer(dl_se)))
return;
dl_se->dl_throttled = 1;
if (dl_se->runtime > 0)
@ -1267,44 +1320,19 @@ static u64 grub_reclaim(u64 delta, struct rq *rq, struct sched_dl_entity *dl_se)
return (delta * u_act) >> BW_SHIFT;
}
/*
* Update the current task's runtime statistics (provided it is still
* a -deadline task and has not been removed from the dl_rq).
*/
static void update_curr_dl(struct rq *rq)
static inline void
update_stats_dequeue_dl(struct dl_rq *dl_rq, struct sched_dl_entity *dl_se,
int flags);
static void update_curr_dl_se(struct rq *rq, struct sched_dl_entity *dl_se, s64 delta_exec)
{
struct task_struct *curr = rq->curr;
struct sched_dl_entity *dl_se = &curr->dl;
u64 delta_exec, scaled_delta_exec;
int cpu = cpu_of(rq);
u64 now;
s64 scaled_delta_exec;
if (!dl_task(curr) || !on_dl_rq(dl_se))
return;
/*
* Consumed budget is computed considering the time as
* observed by schedulable tasks (excluding time spent
* in hardirq context, etc.). Deadlines are instead
* computed using hard walltime. This seems to be the more
* natural solution, but the full ramifications of this
* approach need further study.
*/
now = rq_clock_task(rq);
delta_exec = now - curr->se.exec_start;
if (unlikely((s64)delta_exec <= 0)) {
if (unlikely(delta_exec <= 0)) {
if (unlikely(dl_se->dl_yielded))
goto throttle;
return;
}
schedstat_set(curr->stats.exec_max,
max(curr->stats.exec_max, delta_exec));
trace_sched_stat_runtime(curr, delta_exec, 0);
update_current_exec_runtime(curr, now, delta_exec);
if (dl_entity_is_special(dl_se))
return;
@ -1316,10 +1344,9 @@ static void update_curr_dl(struct rq *rq)
* according to current frequency and CPU maximum capacity.
*/
if (unlikely(dl_se->flags & SCHED_FLAG_RECLAIM)) {
scaled_delta_exec = grub_reclaim(delta_exec,
rq,
&curr->dl);
scaled_delta_exec = grub_reclaim(delta_exec, rq, dl_se);
} else {
int cpu = cpu_of(rq);
unsigned long scale_freq = arch_scale_freq_capacity(cpu);
unsigned long scale_cpu = arch_scale_cpu_capacity(cpu);
@ -1338,11 +1365,20 @@ static void update_curr_dl(struct rq *rq)
(dl_se->flags & SCHED_FLAG_DL_OVERRUN))
dl_se->dl_overrun = 1;
__dequeue_task_dl(rq, curr, 0);
if (unlikely(is_dl_boosted(dl_se) || !start_dl_timer(curr)))
enqueue_task_dl(rq, curr, ENQUEUE_REPLENISH);
dequeue_dl_entity(dl_se, 0);
if (!dl_server(dl_se)) {
update_stats_dequeue_dl(&rq->dl, dl_se, 0);
dequeue_pushable_dl_task(rq, dl_task_of(dl_se));
}
if (!is_leftmost(curr, &rq->dl))
if (unlikely(is_dl_boosted(dl_se) || !start_dl_timer(dl_se))) {
if (dl_server(dl_se))
enqueue_dl_entity(dl_se, ENQUEUE_REPLENISH);
else
enqueue_task_dl(rq, dl_task_of(dl_se), ENQUEUE_REPLENISH);
}
if (!is_leftmost(dl_se, &rq->dl))
resched_curr(rq);
}
@ -1372,20 +1408,82 @@ static void update_curr_dl(struct rq *rq)
}
}
void dl_server_update(struct sched_dl_entity *dl_se, s64 delta_exec)
{
update_curr_dl_se(dl_se->rq, dl_se, delta_exec);
}
void dl_server_start(struct sched_dl_entity *dl_se)
{
if (!dl_server(dl_se)) {
dl_se->dl_server = 1;
setup_new_dl_entity(dl_se);
}
enqueue_dl_entity(dl_se, ENQUEUE_WAKEUP);
}
void dl_server_stop(struct sched_dl_entity *dl_se)
{
dequeue_dl_entity(dl_se, DEQUEUE_SLEEP);
}
void dl_server_init(struct sched_dl_entity *dl_se, struct rq *rq,
dl_server_has_tasks_f has_tasks,
dl_server_pick_f pick)
{
dl_se->rq = rq;
dl_se->server_has_tasks = has_tasks;
dl_se->server_pick = pick;
}
/*
* Update the current task's runtime statistics (provided it is still
* a -deadline task and has not been removed from the dl_rq).
*/
static void update_curr_dl(struct rq *rq)
{
struct task_struct *curr = rq->curr;
struct sched_dl_entity *dl_se = &curr->dl;
s64 delta_exec;
if (!dl_task(curr) || !on_dl_rq(dl_se))
return;
/*
* Consumed budget is computed considering the time as
* observed by schedulable tasks (excluding time spent
* in hardirq context, etc.). Deadlines are instead
* computed using hard walltime. This seems to be the more
* natural solution, but the full ramifications of this
* approach need further study.
*/
delta_exec = update_curr_common(rq);
update_curr_dl_se(rq, dl_se, delta_exec);
}
static enum hrtimer_restart inactive_task_timer(struct hrtimer *timer)
{
struct sched_dl_entity *dl_se = container_of(timer,
struct sched_dl_entity,
inactive_timer);
struct task_struct *p = dl_task_of(dl_se);
struct task_struct *p = NULL;
struct rq_flags rf;
struct rq *rq;
rq = task_rq_lock(p, &rf);
if (!dl_server(dl_se)) {
p = dl_task_of(dl_se);
rq = task_rq_lock(p, &rf);
} else {
rq = dl_se->rq;
rq_lock(rq, &rf);
}
sched_clock_tick();
update_rq_clock(rq);
if (dl_server(dl_se))
goto no_task;
if (!dl_task(p) || READ_ONCE(p->__state) == TASK_DEAD) {
struct dl_bw *dl_b = dl_bw_of(task_cpu(p));
@ -1398,23 +1496,30 @@ static enum hrtimer_restart inactive_task_timer(struct hrtimer *timer)
raw_spin_lock(&dl_b->lock);
__dl_sub(dl_b, p->dl.dl_bw, dl_bw_cpus(task_cpu(p)));
raw_spin_unlock(&dl_b->lock);
__dl_clear_params(p);
__dl_clear_params(dl_se);
goto unlock;
}
no_task:
if (dl_se->dl_non_contending == 0)
goto unlock;
sub_running_bw(dl_se, &rq->dl);
dl_se->dl_non_contending = 0;
unlock:
task_rq_unlock(rq, p, &rf);
put_task_struct(p);
if (!dl_server(dl_se)) {
task_rq_unlock(rq, p, &rf);
put_task_struct(p);
} else {
rq_unlock(rq, &rf);
}
return HRTIMER_NORESTART;
}
void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se)
static void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se)
{
struct hrtimer *timer = &dl_se->inactive_timer;
@ -1472,10 +1577,8 @@ static inline void dec_dl_deadline(struct dl_rq *dl_rq, u64 deadline) {}
static inline
void inc_dl_tasks(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq)
{
int prio = dl_task_of(dl_se)->prio;
u64 deadline = dl_se->deadline;
WARN_ON(!dl_prio(prio));
dl_rq->dl_nr_running++;
add_nr_running(rq_of_dl_rq(dl_rq), 1);
@ -1485,9 +1588,6 @@ void inc_dl_tasks(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq)
static inline
void dec_dl_tasks(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq)
{
int prio = dl_task_of(dl_se)->prio;
WARN_ON(!dl_prio(prio));
WARN_ON(!dl_rq->dl_nr_running);
dl_rq->dl_nr_running--;
sub_nr_running(rq_of_dl_rq(dl_rq), 1);
@ -1608,6 +1708,41 @@ enqueue_dl_entity(struct sched_dl_entity *dl_se, int flags)
update_stats_enqueue_dl(dl_rq_of_se(dl_se), dl_se, flags);
/*
* Check if a constrained deadline task was activated
* after the deadline but before the next period.
* If that is the case, the task will be throttled and
* the replenishment timer will be set to the next period.
*/
if (!dl_se->dl_throttled && !dl_is_implicit(dl_se))
dl_check_constrained_dl(dl_se);
if (flags & (ENQUEUE_RESTORE|ENQUEUE_MIGRATING)) {
struct dl_rq *dl_rq = dl_rq_of_se(dl_se);
add_rq_bw(dl_se, dl_rq);
add_running_bw(dl_se, dl_rq);
}
/*
* If p is throttled, we do not enqueue it. In fact, if it exhausted
* its budget it needs a replenishment and, since it now is on
* its rq, the bandwidth timer callback (which clearly has not
* run yet) will take care of this.
* However, the active utilization does not depend on the fact
* that the task is on the runqueue or not (but depends on the
* task's state - in GRUB parlance, "inactive" vs "active contending").
* In other words, even if a task is throttled its utilization must
* be counted in the active utilization; hence, we need to call
* add_running_bw().
*/
if (dl_se->dl_throttled && !(flags & ENQUEUE_REPLENISH)) {
if (flags & ENQUEUE_WAKEUP)
task_contending(dl_se, flags);
return;
}
/*
* If this is a wakeup or a new instance, the scheduling
* parameters of the task might need updating. Otherwise,
@ -1619,17 +1754,35 @@ enqueue_dl_entity(struct sched_dl_entity *dl_se, int flags)
} else if (flags & ENQUEUE_REPLENISH) {
replenish_dl_entity(dl_se);
} else if ((flags & ENQUEUE_RESTORE) &&
dl_time_before(dl_se->deadline,
rq_clock(rq_of_dl_rq(dl_rq_of_se(dl_se))))) {
dl_time_before(dl_se->deadline, rq_clock(rq_of_dl_se(dl_se)))) {
setup_new_dl_entity(dl_se);
}
__enqueue_dl_entity(dl_se);
}
static void dequeue_dl_entity(struct sched_dl_entity *dl_se)
static void dequeue_dl_entity(struct sched_dl_entity *dl_se, int flags)
{
__dequeue_dl_entity(dl_se);
if (flags & (DEQUEUE_SAVE|DEQUEUE_MIGRATING)) {
struct dl_rq *dl_rq = dl_rq_of_se(dl_se);
sub_running_bw(dl_se, dl_rq);
sub_rq_bw(dl_se, dl_rq);
}
/*
* This check allows to start the inactive timer (or to immediately
* decrease the active utilization, if needed) in two cases:
* when the task blocks and when it is terminating
* (p->state == TASK_DEAD). We can handle the two cases in the same
* way, because from GRUB's point of view the same thing is happening
* (the task moves from "active contending" to "active non contending"
* or "inactive")
*/
if (flags & DEQUEUE_SLEEP)
task_non_contending(dl_se);
}
static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags)
@ -1674,76 +1827,31 @@ static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags)
return;
}
/*
* Check if a constrained deadline task was activated
* after the deadline but before the next period.
* If that is the case, the task will be throttled and
* the replenishment timer will be set to the next period.
*/
if (!p->dl.dl_throttled && !dl_is_implicit(&p->dl))
dl_check_constrained_dl(&p->dl);
if (p->on_rq == TASK_ON_RQ_MIGRATING || flags & ENQUEUE_RESTORE) {
add_rq_bw(&p->dl, &rq->dl);
add_running_bw(&p->dl, &rq->dl);
}
/*
* If p is throttled, we do not enqueue it. In fact, if it exhausted
* its budget it needs a replenishment and, since it now is on
* its rq, the bandwidth timer callback (which clearly has not
* run yet) will take care of this.
* However, the active utilization does not depend on the fact
* that the task is on the runqueue or not (but depends on the
* task's state - in GRUB parlance, "inactive" vs "active contending").
* In other words, even if a task is throttled its utilization must
* be counted in the active utilization; hence, we need to call
* add_running_bw().
*/
if (p->dl.dl_throttled && !(flags & ENQUEUE_REPLENISH)) {
if (flags & ENQUEUE_WAKEUP)
task_contending(&p->dl, flags);
return;
}
check_schedstat_required();
update_stats_wait_start_dl(dl_rq_of_se(&p->dl), &p->dl);
if (p->on_rq == TASK_ON_RQ_MIGRATING)
flags |= ENQUEUE_MIGRATING;
enqueue_dl_entity(&p->dl, flags);
if (!task_current(rq, p) && p->nr_cpus_allowed > 1)
enqueue_pushable_dl_task(rq, p);
}
if (dl_server(&p->dl))
return;
static void __dequeue_task_dl(struct rq *rq, struct task_struct *p, int flags)
{
update_stats_dequeue_dl(&rq->dl, &p->dl, flags);
dequeue_dl_entity(&p->dl);
dequeue_pushable_dl_task(rq, p);
if (!task_current(rq, p) && !p->dl.dl_throttled && p->nr_cpus_allowed > 1)
enqueue_pushable_dl_task(rq, p);
}
static void dequeue_task_dl(struct rq *rq, struct task_struct *p, int flags)
{
update_curr_dl(rq);
__dequeue_task_dl(rq, p, flags);
if (p->on_rq == TASK_ON_RQ_MIGRATING || flags & DEQUEUE_SAVE) {
sub_running_bw(&p->dl, &rq->dl);
sub_rq_bw(&p->dl, &rq->dl);
}
if (p->on_rq == TASK_ON_RQ_MIGRATING)
flags |= DEQUEUE_MIGRATING;
/*
* This check allows to start the inactive timer (or to immediately
* decrease the active utilization, if needed) in two cases:
* when the task blocks and when it is terminating
* (p->state == TASK_DEAD). We can handle the two cases in the same
* way, because from GRUB's point of view the same thing is happening
* (the task moves from "active contending" to "active non contending"
* or "inactive")
*/
if (flags & DEQUEUE_SLEEP)
task_non_contending(p);
dequeue_dl_entity(&p->dl, flags);
if (!p->dl.dl_throttled && !dl_server(&p->dl))
dequeue_pushable_dl_task(rq, p);
}
/*
@ -1933,12 +2041,12 @@ static void wakeup_preempt_dl(struct rq *rq, struct task_struct *p,
}
#ifdef CONFIG_SCHED_HRTICK
static void start_hrtick_dl(struct rq *rq, struct task_struct *p)
static void start_hrtick_dl(struct rq *rq, struct sched_dl_entity *dl_se)
{
hrtick_start(rq, p->dl.runtime);
hrtick_start(rq, dl_se->runtime);
}
#else /* !CONFIG_SCHED_HRTICK */
static void start_hrtick_dl(struct rq *rq, struct task_struct *p)
static void start_hrtick_dl(struct rq *rq, struct sched_dl_entity *dl_se)
{
}
#endif
@ -1958,9 +2066,6 @@ static void set_next_task_dl(struct rq *rq, struct task_struct *p, bool first)
if (!first)
return;
if (hrtick_enabled_dl(rq))
start_hrtick_dl(rq, p);
if (rq->curr->sched_class != &dl_sched_class)
update_dl_rq_load_avg(rq_clock_pelt(rq), rq, 0);
@ -1983,12 +2088,25 @@ static struct task_struct *pick_task_dl(struct rq *rq)
struct dl_rq *dl_rq = &rq->dl;
struct task_struct *p;
again:
if (!sched_dl_runnable(rq))
return NULL;
dl_se = pick_next_dl_entity(dl_rq);
WARN_ON_ONCE(!dl_se);
p = dl_task_of(dl_se);
if (dl_server(dl_se)) {
p = dl_se->server_pick(dl_se);
if (!p) {
WARN_ON_ONCE(1);
dl_se->dl_yielded = 1;
update_curr_dl_se(rq, dl_se, 0);
goto again;
}
p->dl_server = dl_se;
} else {
p = dl_task_of(dl_se);
}
return p;
}
@ -1998,9 +2116,15 @@ static struct task_struct *pick_next_task_dl(struct rq *rq)
struct task_struct *p;
p = pick_task_dl(rq);
if (p)
if (!p)
return p;
if (!p->dl_server)
set_next_task_dl(rq, p, true);
if (hrtick_enabled(rq))
start_hrtick_dl(rq, &p->dl);
return p;
}
@ -2038,8 +2162,8 @@ static void task_tick_dl(struct rq *rq, struct task_struct *p, int queued)
* be set and schedule() will start a new hrtick for the next task.
*/
if (hrtick_enabled_dl(rq) && queued && p->dl.runtime > 0 &&
is_leftmost(p, &rq->dl))
start_hrtick_dl(rq, p);
is_leftmost(&p->dl, &rq->dl))
start_hrtick_dl(rq, &p->dl);
}
static void task_fork_dl(struct task_struct *p)
@ -2558,7 +2682,7 @@ static void switched_from_dl(struct rq *rq, struct task_struct *p)
* will reset the task parameters.
*/
if (task_on_rq_queued(p) && p->dl.dl_runtime)
task_non_contending(p);
task_non_contending(&p->dl);
/*
* In case a task is setscheduled out from SCHED_DEADLINE we need to
@ -2966,10 +3090,8 @@ bool __checkparam_dl(const struct sched_attr *attr)
/*
* This function clears the sched_dl_entity static params.
*/
void __dl_clear_params(struct task_struct *p)
static void __dl_clear_params(struct sched_dl_entity *dl_se)
{
struct sched_dl_entity *dl_se = &p->dl;
dl_se->dl_runtime = 0;
dl_se->dl_deadline = 0;
dl_se->dl_period = 0;
@ -2981,12 +3103,21 @@ void __dl_clear_params(struct task_struct *p)
dl_se->dl_yielded = 0;
dl_se->dl_non_contending = 0;
dl_se->dl_overrun = 0;
dl_se->dl_server = 0;
#ifdef CONFIG_RT_MUTEXES
dl_se->pi_se = dl_se;
#endif
}
void init_dl_entity(struct sched_dl_entity *dl_se)
{
RB_CLEAR_NODE(&dl_se->rb_node);
init_dl_task_timer(dl_se);
init_dl_inactive_task_timer(dl_se);
__dl_clear_params(dl_se);
}
bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr)
{
struct sched_dl_entity *dl_se = &p->dl;

18
kernel/sched/debug.c
View File

@ -628,8 +628,8 @@ static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu)
void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
{
s64 left_vruntime = -1, min_vruntime, right_vruntime = -1, spread;
struct sched_entity *last, *first;
s64 left_vruntime = -1, min_vruntime, right_vruntime = -1, left_deadline = -1, spread;
struct sched_entity *last, *first, *root;
struct rq *rq = cpu_rq(cpu);
unsigned long flags;
@ -644,15 +644,20 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
SPLIT_NS(cfs_rq->exec_clock));
raw_spin_rq_lock_irqsave(rq, flags);
root = __pick_root_entity(cfs_rq);
if (root)
left_vruntime = root->min_vruntime;
first = __pick_first_entity(cfs_rq);
if (first)
left_vruntime = first->vruntime;
left_deadline = first->deadline;
last = __pick_last_entity(cfs_rq);
if (last)
right_vruntime = last->vruntime;
min_vruntime = cfs_rq->min_vruntime;
raw_spin_rq_unlock_irqrestore(rq, flags);
SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "left_deadline",
SPLIT_NS(left_deadline));
SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "left_vruntime",
SPLIT_NS(left_vruntime));
SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "min_vruntime",
@ -679,8 +684,8 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
cfs_rq->avg.runnable_avg);
SEQ_printf(m, " .%-30s: %lu\n", "util_avg",
cfs_rq->avg.util_avg);
SEQ_printf(m, " .%-30s: %u\n", "util_est_enqueued",
cfs_rq->avg.util_est.enqueued);
SEQ_printf(m, " .%-30s: %u\n", "util_est",
cfs_rq->avg.util_est);
SEQ_printf(m, " .%-30s: %ld\n", "removed.load_avg",
cfs_rq->removed.load_avg);
SEQ_printf(m, " .%-30s: %ld\n", "removed.util_avg",
@ -1070,8 +1075,7 @@ void proc_sched_show_task(struct task_struct *p, struct pid_namespace *ns,
P(se.avg.runnable_avg);
P(se.avg.util_avg);
P(se.avg.last_update_time);
P(se.avg.util_est.ewma);
PM(se.avg.util_est.enqueued, ~UTIL_AVG_UNCHANGED);
PM(se.avg.util_est, ~UTIL_AVG_UNCHANGED);
#endif
#ifdef CONFIG_UCLAMP_TASK
__PS("uclamp.min", p->uclamp_req[UCLAMP_MIN].value);

449
kernel/sched/fair.c
View File

@ -551,7 +551,11 @@ static inline u64 min_vruntime(u64 min_vruntime, u64 vruntime)
static inline bool entity_before(const struct sched_entity *a,
const struct sched_entity *b)
{
return (s64)(a->vruntime - b->vruntime) < 0;
/*
* Tiebreak on vruntime seems unnecessary since it can
* hardly happen.
*/
return (s64)(a->deadline - b->deadline) < 0;
}
static inline s64 entity_key(struct cfs_rq *cfs_rq, struct sched_entity *se)
@ -720,7 +724,7 @@ static void update_entity_lag(struct cfs_rq *cfs_rq, struct sched_entity *se)
* Note: using 'avg_vruntime() > se->vruntime' is inacurate due
* to the loss in precision caused by the division.
*/
int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se)
static int vruntime_eligible(struct cfs_rq *cfs_rq, u64 vruntime)
{
struct sched_entity *curr = cfs_rq->curr;
s64 avg = cfs_rq->avg_vruntime;
@ -733,7 +737,12 @@ int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se)
load += weight;
}
return avg >= entity_key(cfs_rq, se) * load;
return avg >= (s64)(vruntime - cfs_rq->min_vruntime) * load;
}
int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
return vruntime_eligible(cfs_rq, se->vruntime);
}
static u64 __update_min_vruntime(struct cfs_rq *cfs_rq, u64 vruntime)
@ -752,9 +761,8 @@ static u64 __update_min_vruntime(struct cfs_rq *cfs_rq, u64 vruntime)
static void update_min_vruntime(struct cfs_rq *cfs_rq)
{
struct sched_entity *se = __pick_first_entity(cfs_rq);
struct sched_entity *se = __pick_root_entity(cfs_rq);
struct sched_entity *curr = cfs_rq->curr;
u64 vruntime = cfs_rq->min_vruntime;
if (curr) {
@ -766,9 +774,9 @@ static void update_min_vruntime(struct cfs_rq *cfs_rq)
if (se) {
if (!curr)
vruntime = se->vruntime;
vruntime = se->min_vruntime;
else
vruntime = min_vruntime(vruntime, se->vruntime);
vruntime = min_vruntime(vruntime, se->min_vruntime);
}
/* ensure we never gain time by being placed backwards. */
@ -781,34 +789,34 @@ static inline bool __entity_less(struct rb_node *a, const struct rb_node *b)
return entity_before(__node_2_se(a), __node_2_se(b));
}
#define deadline_gt(field, lse, rse) ({ (s64)((lse)->field - (rse)->field) > 0; })
#define vruntime_gt(field, lse, rse) ({ (s64)((lse)->field - (rse)->field) > 0; })
static inline void __update_min_deadline(struct sched_entity *se, struct rb_node *node)
static inline void __min_vruntime_update(struct sched_entity *se, struct rb_node *node)
{
if (node) {
struct sched_entity *rse = __node_2_se(node);
if (deadline_gt(min_deadline, se, rse))
se->min_deadline = rse->min_deadline;
if (vruntime_gt(min_vruntime, se, rse))
se->min_vruntime = rse->min_vruntime;
}
}
/*
* se->min_deadline = min(se->deadline, left->min_deadline, right->min_deadline)
* se->min_vruntime = min(se->vruntime, {left,right}->min_vruntime)
*/
static inline bool min_deadline_update(struct sched_entity *se, bool exit)
static inline bool min_vruntime_update(struct sched_entity *se, bool exit)
{
u64 old_min_deadline = se->min_deadline;
u64 old_min_vruntime = se->min_vruntime;
struct rb_node *node = &se->run_node;
se->min_deadline = se->deadline;
__update_min_deadline(se, node->rb_right);
__update_min_deadline(se, node->rb_left);
se->min_vruntime = se->vruntime;
__min_vruntime_update(se, node->rb_right);
__min_vruntime_update(se, node->rb_left);
return se->min_deadline == old_min_deadline;
return se->min_vruntime == old_min_vruntime;
}
RB_DECLARE_CALLBACKS(static, min_deadline_cb, struct sched_entity,
run_node, min_deadline, min_deadline_update);
RB_DECLARE_CALLBACKS(static, min_vruntime_cb, struct sched_entity,
run_node, min_vruntime, min_vruntime_update);
/*
* Enqueue an entity into the rb-tree:
@ -816,18 +824,28 @@ RB_DECLARE_CALLBACKS(static, min_deadline_cb, struct sched_entity,
static void __enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
avg_vruntime_add(cfs_rq, se);
se->min_deadline = se->deadline;
se->min_vruntime = se->vruntime;
rb_add_augmented_cached(&se->run_node, &cfs_rq->tasks_timeline,
__entity_less, &min_deadline_cb);
__entity_less, &min_vruntime_cb);
}
static void __dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
rb_erase_augmented_cached(&se->run_node, &cfs_rq->tasks_timeline,
&min_deadline_cb);
&min_vruntime_cb);
avg_vruntime_sub(cfs_rq, se);
}
struct sched_entity *__pick_root_entity(struct cfs_rq *cfs_rq)
{
struct rb_node *root = cfs_rq->tasks_timeline.rb_root.rb_node;
if (!root)
return NULL;
return __node_2_se(root);
}
struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq)
{
struct rb_node *left = rb_first_cached(&cfs_rq->tasks_timeline);
@ -850,23 +868,29 @@ struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq)
* with the earliest virtual deadline.
*
* We can do this in O(log n) time due to an augmented RB-tree. The
* tree keeps the entries sorted on service, but also functions as a
* heap based on the deadline by keeping:
* tree keeps the entries sorted on deadline, but also functions as a
* heap based on the vruntime by keeping:
*
* se->min_deadline = min(se->deadline, se->{left,right}->min_deadline)
* se->min_vruntime = min(se->vruntime, se->{left,right}->min_vruntime)
*
* Which allows an EDF like search on (sub)trees.
* Which allows tree pruning through eligibility.
*/
static struct sched_entity *__pick_eevdf(struct cfs_rq *cfs_rq)
static struct sched_entity *pick_eevdf(struct cfs_rq *cfs_rq)
{
struct rb_node *node = cfs_rq->tasks_timeline.rb_root.rb_node;
struct sched_entity *se = __pick_first_entity(cfs_rq);
struct sched_entity *curr = cfs_rq->curr;
struct sched_entity *best = NULL;
struct sched_entity *best_left = NULL;
/*
* We can safely skip eligibility check if there is only one entity
* in this cfs_rq, saving some cycles.
*/
if (cfs_rq->nr_running == 1)
return curr && curr->on_rq ? curr : se;
if (curr && (!curr->on_rq || !entity_eligible(cfs_rq, curr)))
curr = NULL;
best = curr;
/*
* Once selected, run a task until it either becomes non-eligible or
@ -875,95 +899,45 @@ static struct sched_entity *__pick_eevdf(struct cfs_rq *cfs_rq)
if (sched_feat(RUN_TO_PARITY) && curr && curr->vlag == curr->deadline)
return curr;
/* Pick the leftmost entity if it's eligible */
if (se && entity_eligible(cfs_rq, se)) {
best = se;
goto found;
}
/* Heap search for the EEVD entity */
while (node) {
struct sched_entity *se = __node_2_se(node);
struct rb_node *left = node->rb_left;
/*
* If this entity is not eligible, try the left subtree.
* Eligible entities in left subtree are always better
* choices, since they have earlier deadlines.
*/
if (!entity_eligible(cfs_rq, se)) {
node = node->rb_left;
if (left && vruntime_eligible(cfs_rq,
__node_2_se(left)->min_vruntime)) {
node = left;
continue;
}
se = __node_2_se(node);
/*
* Now we heap search eligible trees for the best (min_)deadline
* The left subtree either is empty or has no eligible
* entity, so check the current node since it is the one
* with earliest deadline that might be eligible.
*/
if (!best || deadline_gt(deadline, best, se))
if (entity_eligible(cfs_rq, se)) {
best = se;
/*
* Every se in a left branch is eligible, keep track of the
* branch with the best min_deadline
*/
if (node->rb_left) {
struct sched_entity *left = __node_2_se(node->rb_left);
if (!best_left || deadline_gt(min_deadline, best_left, left))
best_left = left;
/*
* min_deadline is in the left branch. rb_left and all
* descendants are eligible, so immediately switch to the second
* loop.
*/
if (left->min_deadline == se->min_deadline)
break;
}
/* min_deadline is at this node, no need to look right */
if (se->deadline == se->min_deadline)
break;
/* else min_deadline is in the right branch. */
node = node->rb_right;
}
/*
* We ran into an eligible node which is itself the best.
* (Or nr_running == 0 and both are NULL)
*/
if (!best_left || (s64)(best_left->min_deadline - best->deadline) > 0)
return best;
/*
* Now best_left and all of its children are eligible, and we are just
* looking for deadline == min_deadline
*/
node = &best_left->run_node;
while (node) {
struct sched_entity *se = __node_2_se(node);
/* min_deadline is the current node */
if (se->deadline == se->min_deadline)
return se;
/* min_deadline is in the left branch */
if (node->rb_left &&
__node_2_se(node->rb_left)->min_deadline == se->min_deadline) {
node = node->rb_left;
continue;
}
/* else min_deadline is in the right branch */
node = node->rb_right;
}
return NULL;
}
found:
if (!best || (curr && entity_before(curr, best)))
best = curr;
static struct sched_entity *pick_eevdf(struct cfs_rq *cfs_rq)
{
struct sched_entity *se = __pick_eevdf(cfs_rq);
if (!se) {
struct sched_entity *left = __pick_first_entity(cfs_rq);
if (left) {
pr_err("EEVDF scheduling fail, picking leftmost\n");
return left;
}
}
return se;
return best;
}
#ifdef CONFIG_SCHED_DEBUG
@ -1129,23 +1103,17 @@ static void update_tg_load_avg(struct cfs_rq *cfs_rq)
}
#endif /* CONFIG_SMP */
/*
* Update the current task's runtime statistics.
*/
static void update_curr(struct cfs_rq *cfs_rq)
static s64 update_curr_se(struct rq *rq, struct sched_entity *curr)
{
struct sched_entity *curr = cfs_rq->curr;
u64 now = rq_clock_task(rq_of(cfs_rq));
u64 delta_exec;
if (unlikely(!curr))
return;
u64 now = rq_clock_task(rq);
s64 delta_exec;
delta_exec = now - curr->exec_start;
if (unlikely((s64)delta_exec <= 0))
return;
if (unlikely(delta_exec <= 0))
return delta_exec;
curr->exec_start = now;
curr->sum_exec_runtime += delta_exec;
if (schedstat_enabled()) {
struct sched_statistics *stats;
@ -1155,20 +1123,54 @@ static void update_curr(struct cfs_rq *cfs_rq)
max(delta_exec, stats->exec_max));
}
curr->sum_exec_runtime += delta_exec;
schedstat_add(cfs_rq->exec_clock, delta_exec);
return delta_exec;
}
static inline void update_curr_task(struct task_struct *p, s64 delta_exec)
{
trace_sched_stat_runtime(p, delta_exec);
account_group_exec_runtime(p, delta_exec);
cgroup_account_cputime(p, delta_exec);
if (p->dl_server)
dl_server_update(p->dl_server, delta_exec);
}
/*
* Used by other classes to account runtime.
*/
s64 update_curr_common(struct rq *rq)
{
struct task_struct *curr = rq->curr;
s64 delta_exec;
delta_exec = update_curr_se(rq, &curr->se);
if (likely(delta_exec > 0))
update_curr_task(curr, delta_exec);
return delta_exec;
}
/*
* Update the current task's runtime statistics.
*/
static void update_curr(struct cfs_rq *cfs_rq)
{
struct sched_entity *curr = cfs_rq->curr;
s64 delta_exec;
if (unlikely(!curr))
return;
delta_exec = update_curr_se(rq_of(cfs_rq), curr);
if (unlikely(delta_exec <= 0))
return;
curr->vruntime += calc_delta_fair(delta_exec, curr);
update_deadline(cfs_rq, curr);
update_min_vruntime(cfs_rq);
if (entity_is_task(curr)) {
struct task_struct *curtask = task_of(curr);
trace_sched_stat_runtime(curtask, delta_exec, curr->vruntime);
cgroup_account_cputime(curtask, delta_exec);
account_group_exec_runtime(curtask, delta_exec);
}
if (entity_is_task(curr))
update_curr_task(task_of(curr), delta_exec);
account_cfs_rq_runtime(cfs_rq, delta_exec);
}
@ -3164,7 +3166,7 @@ static bool vma_is_accessed(struct mm_struct *mm, struct vm_area_struct *vma)
* This is also done to avoid any side effect of task scanning
* amplifying the unfairness of disjoint set of VMAs' access.
*/
if (READ_ONCE(current->mm->numa_scan_seq) < 2)
if ((READ_ONCE(current->mm->numa_scan_seq) - vma->numab_state->start_scan_seq) < 2)
return true;
pids = vma->numab_state->pids_active[0] | vma->numab_state->pids_active[1];
@ -3307,6 +3309,8 @@ static void task_numa_work(struct callback_head *work)
if (!vma->numab_state)
continue;
vma->numab_state->start_scan_seq = mm->numa_scan_seq;
vma->numab_state->next_scan = now +
msecs_to_jiffies(sysctl_numa_balancing_scan_delay);
@ -3811,17 +3815,17 @@ static void reweight_entity(struct cfs_rq *cfs_rq, struct sched_entity *se,
enqueue_load_avg(cfs_rq, se);
if (se->on_rq) {
update_load_add(&cfs_rq->load, se->load.weight);
if (!curr) {
/*
* The entity's vruntime has been adjusted, so let's check
* whether the rq-wide min_vruntime needs updated too. Since
* the calculations above require stable min_vruntime rather
* than up-to-date one, we do the update at the end of the
* reweight process.
*/
if (!curr)
__enqueue_entity(cfs_rq, se);
update_min_vruntime(cfs_rq);
}
/*
* The entity's vruntime has been adjusted, so let's check
* whether the rq-wide min_vruntime needs updated too. Since
* the calculations above require stable min_vruntime rather
* than up-to-date one, we do the update at the end of the
* reweight process.
*/
update_min_vruntime(cfs_rq);
}
}
@ -4096,6 +4100,10 @@ static inline void update_tg_load_avg(struct cfs_rq *cfs_rq)
if (cfs_rq->tg == &root_task_group)
return;
/* rq has been offline and doesn't contribute to the share anymore: */
if (!cpu_active(cpu_of(rq_of(cfs_rq))))
return;
/*
* For migration heavy workloads, access to tg->load_avg can be
* unbound. Limit the update rate to at most once per ms.
@ -4112,6 +4120,49 @@ static inline void update_tg_load_avg(struct cfs_rq *cfs_rq)
}
}
static inline void clear_tg_load_avg(struct cfs_rq *cfs_rq)
{
long delta;
u64 now;
/*
* No need to update load_avg for root_task_group, as it is not used.
*/
if (cfs_rq->tg == &root_task_group)
return;
now = sched_clock_cpu(cpu_of(rq_of(cfs_rq)));
delta = 0 - cfs_rq->tg_load_avg_contrib;
atomic_long_add(delta, &cfs_rq->tg->load_avg);
cfs_rq->tg_load_avg_contrib = 0;
cfs_rq->last_update_tg_load_avg = now;
}
/* CPU offline callback: */
static void __maybe_unused clear_tg_offline_cfs_rqs(struct rq *rq)
{
struct task_group *tg;
lockdep_assert_rq_held(rq);
/*
* The rq clock has already been updated in
* set_rq_offline(), so we should skip updating
* the rq clock again in unthrottle_cfs_rq().
*/
rq_clock_start_loop_update(rq);
rcu_read_lock();
list_for_each_entry_rcu(tg, &task_groups, list) {
struct cfs_rq *cfs_rq = tg->cfs_rq[cpu_of(rq)];
clear_tg_load_avg(cfs_rq);
}
rcu_read_unlock();
rq_clock_stop_loop_update(rq);
}
/*
* Called within set_task_rq() right before setting a task's CPU. The
* caller only guarantees p->pi_lock is held; no other assumptions,
@ -4408,6 +4459,8 @@ static inline bool skip_blocked_update(struct sched_entity *se)
static inline void update_tg_load_avg(struct cfs_rq *cfs_rq) {}
static inline void clear_tg_offline_cfs_rqs(struct rq *rq) {}
static inline int propagate_entity_load_avg(struct sched_entity *se)
{
return 0;
@ -4770,11 +4823,14 @@ static inline unsigned long task_util(struct task_struct *p)
return READ_ONCE(p->se.avg.util_avg);
}
static inline unsigned long task_runnable(struct task_struct *p)
{
return READ_ONCE(p->se.avg.runnable_avg);
}
static inline unsigned long _task_util_est(struct task_struct *p)
{
struct util_est ue = READ_ONCE(p->se.avg.util_est);
return max(ue.ewma, (ue.enqueued & ~UTIL_AVG_UNCHANGED));
return READ_ONCE(p->se.avg.util_est) & ~UTIL_AVG_UNCHANGED;
}
static inline unsigned long task_util_est(struct task_struct *p)
@ -4791,9 +4847,9 @@ static inline void util_est_enqueue(struct cfs_rq *cfs_rq,
return;
/* Update root cfs_rq's estimated utilization */
enqueued = cfs_rq->avg.util_est.enqueued;
enqueued = cfs_rq->avg.util_est;
enqueued += _task_util_est(p);
WRITE_ONCE(cfs_rq->avg.util_est.enqueued, enqueued);
WRITE_ONCE(cfs_rq->avg.util_est, enqueued);
trace_sched_util_est_cfs_tp(cfs_rq);
}
@ -4807,34 +4863,20 @@ static inline void util_est_dequeue(struct cfs_rq *cfs_rq,
return;
/* Update root cfs_rq's estimated utilization */
enqueued = cfs_rq->avg.util_est.enqueued;
enqueued = cfs_rq->avg.util_est;
enqueued -= min_t(unsigned int, enqueued, _task_util_est(p));
WRITE_ONCE(cfs_rq->avg.util_est.enqueued, enqueued);
WRITE_ONCE(cfs_rq->avg.util_est, enqueued);
trace_sched_util_est_cfs_tp(cfs_rq);
}
#define UTIL_EST_MARGIN (SCHED_CAPACITY_SCALE / 100)
/*
* Check if a (signed) value is within a specified (unsigned) margin,
* based on the observation that:
*
* abs(x) < y := (unsigned)(x + y - 1) < (2 * y - 1)
*
* NOTE: this only works when value + margin < INT_MAX.
*/
static inline bool within_margin(int value, int margin)
{
return ((unsigned int)(value + margin - 1) < (2 * margin - 1));
}
static inline void util_est_update(struct cfs_rq *cfs_rq,
struct task_struct *p,
bool task_sleep)
{
long last_ewma_diff, last_enqueued_diff;
struct util_est ue;
unsigned int ewma, dequeued, last_ewma_diff;
if (!sched_feat(UTIL_EST))
return;
@ -4846,71 +4888,73 @@ static inline void util_est_update(struct cfs_rq *cfs_rq,
if (!task_sleep)
return;
/* Get current estimate of utilization */
ewma = READ_ONCE(p->se.avg.util_est);
/*
* If the PELT values haven't changed since enqueue time,
* skip the util_est update.
*/
ue = p->se.avg.util_est;
if (ue.enqueued & UTIL_AVG_UNCHANGED)
if (ewma & UTIL_AVG_UNCHANGED)
return;
last_enqueued_diff = ue.enqueued;
/* Get utilization at dequeue */
dequeued = task_util(p);
/*
* Reset EWMA on utilization increases, the moving average is used only
* to smooth utilization decreases.
*/
ue.enqueued = task_util(p);
if (sched_feat(UTIL_EST_FASTUP)) {
if (ue.ewma < ue.enqueued) {
ue.ewma = ue.enqueued;
goto done;
}
if (ewma <= dequeued) {
ewma = dequeued;
goto done;
}
/*
* Skip update of task's estimated utilization when its members are
* already ~1% close to its last activation value.
*/
last_ewma_diff = ue.enqueued - ue.ewma;
last_enqueued_diff -= ue.enqueued;
if (within_margin(last_ewma_diff, UTIL_EST_MARGIN)) {
if (!within_margin(last_enqueued_diff, UTIL_EST_MARGIN))
goto done;
return;
}
last_ewma_diff = ewma - dequeued;
if (last_ewma_diff < UTIL_EST_MARGIN)
goto done;
/*
* To avoid overestimation of actual task utilization, skip updates if
* we cannot grant there is idle time in this CPU.
*/
if (task_util(p) > arch_scale_cpu_capacity(cpu_of(rq_of(cfs_rq))))
if (dequeued > arch_scale_cpu_capacity(cpu_of(rq_of(cfs_rq))))
return;
/*
* To avoid underestimate of task utilization, skip updates of EWMA if
* we cannot grant that thread got all CPU time it wanted.
*/
if ((dequeued + UTIL_EST_MARGIN) < task_runnable(p))
goto done;
/*
* Update Task's estimated utilization
*
* When *p completes an activation we can consolidate another sample
* of the task size. This is done by storing the current PELT value
* as ue.enqueued and by using this value to update the Exponential
* Weighted Moving Average (EWMA):
* of the task size. This is done by using this value to update the
* Exponential Weighted Moving Average (EWMA):
*
* ewma(t) = w * task_util(p) + (1-w) * ewma(t-1)
* = w * task_util(p) + ewma(t-1) - w * ewma(t-1)
* = w * (task_util(p) - ewma(t-1)) + ewma(t-1)
* = w * ( last_ewma_diff ) + ewma(t-1)
* = w * (last_ewma_diff + ewma(t-1) / w)
* = w * ( -last_ewma_diff ) + ewma(t-1)
* = w * (-last_ewma_diff + ewma(t-1) / w)
*
* Where 'w' is the weight of new samples, which is configured to be
* 0.25, thus making w=1/4 ( >>= UTIL_EST_WEIGHT_SHIFT)
*/
ue.ewma <<= UTIL_EST_WEIGHT_SHIFT;
ue.ewma += last_ewma_diff;
ue.ewma >>= UTIL_EST_WEIGHT_SHIFT;
ewma <<= UTIL_EST_WEIGHT_SHIFT;
ewma -= last_ewma_diff;
ewma >>= UTIL_EST_WEIGHT_SHIFT;
done:
ue.enqueued |= UTIL_AVG_UNCHANGED;
WRITE_ONCE(p->se.avg.util_est, ue);
ewma |= UTIL_AVG_UNCHANGED;
WRITE_ONCE(p->se.avg.util_est, ewma);
trace_sched_util_est_se_tp(&p->se);
}
@ -7638,16 +7682,16 @@ cpu_util(int cpu, struct task_struct *p, int dst_cpu, int boost)
if (sched_feat(UTIL_EST)) {
unsigned long util_est;
util_est = READ_ONCE(cfs_rq->avg.util_est.enqueued);
util_est = READ_ONCE(cfs_rq->avg.util_est);
/*
* During wake-up @p isn't enqueued yet and doesn't contribute
* to any cpu_rq(cpu)->cfs.avg.util_est.enqueued.
* to any cpu_rq(cpu)->cfs.avg.util_est.
* If @dst_cpu == @cpu add it to "simulate" cpu_util after @p
* has been enqueued.
*
* During exec (@dst_cpu = -1) @p is enqueued and does
* contribute to cpu_rq(cpu)->cfs.util_est.enqueued.
* contribute to cpu_rq(cpu)->cfs.util_est.
* Remove it to "simulate" cpu_util without @p's contribution.
*
* Despite the task_on_rq_queued(@p) check there is still a
@ -7776,7 +7820,7 @@ static inline void eenv_pd_busy_time(struct energy_env *eenv,
for_each_cpu(cpu, pd_cpus) {
unsigned long util = cpu_util(cpu, p, -1, 0);
busy_time += effective_cpu_util(cpu, util, ENERGY_UTIL, NULL);
busy_time += effective_cpu_util(cpu, util, NULL, NULL);
}
eenv->pd_busy_time = min(eenv->pd_cap, busy_time);
@ -7799,7 +7843,7 @@ eenv_pd_max_util(struct energy_env *eenv, struct cpumask *pd_cpus,
for_each_cpu(cpu, pd_cpus) {
struct task_struct *tsk = (cpu == dst_cpu) ? p : NULL;
unsigned long util = cpu_util(cpu, p, dst_cpu, 1);
unsigned long eff_util;
unsigned long eff_util, min, max;
/*
* Performance domain frequency: utilization clamping
@ -7808,7 +7852,23 @@ eenv_pd_max_util(struct energy_env *eenv, struct cpumask *pd_cpus,
* NOTE: in case RT tasks are running, by default the
* FREQUENCY_UTIL's utilization can be max OPP.
*/
eff_util = effective_cpu_util(cpu, util, FREQUENCY_UTIL, tsk);
eff_util = effective_cpu_util(cpu, util, &min, &max);
/* Task's uclamp can modify min and max value */
if (tsk && uclamp_is_used()) {
min = max(min, uclamp_eff_value(p, UCLAMP_MIN));
/*
* If there is no active max uclamp constraint,
* directly use task's one, otherwise keep max.
*/
if (uclamp_rq_is_idle(cpu_rq(cpu)))
max = uclamp_eff_value(p, UCLAMP_MAX);
else
max = max(max, uclamp_eff_value(p, UCLAMP_MAX));
}
eff_util = sugov_effective_cpu_perf(cpu, eff_util, min, max);
max_util = max(max_util, eff_util);
}
@ -8210,7 +8270,6 @@ static void check_preempt_wakeup_fair(struct rq *rq, struct task_struct *p, int
struct task_struct *curr = rq->curr;
struct sched_entity *se = &curr->se, *pse = &p->se;
struct cfs_rq *cfs_rq = task_cfs_rq(curr);
int next_buddy_marked = 0;
int cse_is_idle, pse_is_idle;
if (unlikely(se == pse))
@ -8227,7 +8286,6 @@ static void check_preempt_wakeup_fair(struct rq *rq, struct task_struct *p, int
if (sched_feat(NEXT_BUDDY) && !(wake_flags & WF_FORK)) {
set_next_buddy(pse);
next_buddy_marked = 1;
}
/*
@ -9060,7 +9118,7 @@ static int detach_tasks(struct lb_env *env)
case migrate_util:
util = task_util_est(p);
if (util > env->imbalance)
if (shr_bound(util, env->sd->nr_balance_failed) > env->imbalance)
goto next;
env->imbalance -= util;
@ -12413,6 +12471,9 @@ static void rq_offline_fair(struct rq *rq)
/* Ensure any throttled groups are reachable by pick_next_task */
unthrottle_offline_cfs_rqs(rq);
/* Ensure that we remove rq contribution to group share: */
clear_tg_offline_cfs_rqs(rq);
}
#endif /* CONFIG_SMP */

1
kernel/sched/features.h
View File

@ -83,7 +83,6 @@ SCHED_FEAT(WA_BIAS, true)
* UtilEstimation. Use estimated CPU utilization.
*/
SCHED_FEAT(UTIL_EST, true)
SCHED_FEAT(UTIL_EST_FASTUP, true)
SCHED_FEAT(LATENCY_WARN, false)

30
kernel/sched/idle.c
View File

@ -258,6 +258,36 @@ static void do_idle(void)
while (!need_resched()) {
rmb();
/*
* Interrupts shouldn't be re-enabled from that point on until
* the CPU sleeping instruction is reached. Otherwise an interrupt
* may fire and queue a timer that would be ignored until the CPU
* wakes from the sleeping instruction. And testing need_resched()
* doesn't tell about pending needed timer reprogram.
*
* Several cases to consider:
*
* - SLEEP-UNTIL-PENDING-INTERRUPT based instructions such as
* "wfi" or "mwait" are fine because they can be entered with
* interrupt disabled.
*
* - sti;mwait() couple is fine because the interrupts are
* re-enabled only upon the execution of mwait, leaving no gap
* in-between.
*
* - ROLLBACK based idle handlers with the sleeping instruction
* called with interrupts enabled are NOT fine. In this scheme
* when the interrupt detects it has interrupted an idle handler,
* it rolls back to its beginning which performs the
* need_resched() check before re-executing the sleeping
* instruction. This can leak a pending needed timer reprogram.
* If such a scheme is really mandatory due to the lack of an
* appropriate CPU sleeping instruction, then a FAST-FORWARD
* must instead be applied: when the interrupt detects it has
* interrupted an idle handler, it must resume to the end of
* this idle handler so that the generic idle loop is iterated
* again to reprogram the tick.
*/
local_irq_disable();
if (cpu_is_offline(cpu)) {

4
kernel/sched/pelt.h
View File

@ -52,13 +52,13 @@ static inline void cfs_se_util_change(struct sched_avg *avg)
return;
/* Avoid store if the flag has been already reset */
enqueued = avg->util_est.enqueued;
enqueued = avg->util_est;
if (!(enqueued & UTIL_AVG_UNCHANGED))
return;
/* Reset flag to report util_avg has been updated */
enqueued &= ~UTIL_AVG_UNCHANGED;
WRITE_ONCE(avg->util_est.enqueued, enqueued);
WRITE_ONCE(avg->util_est, enqueued);
}
static inline u64 rq_clock_pelt(struct rq *rq)

15
kernel/sched/rt.c
View File

@ -1002,24 +1002,15 @@ static void update_curr_rt(struct rq *rq)
{
struct task_struct *curr = rq->curr;
struct sched_rt_entity *rt_se = &curr->rt;
u64 delta_exec;
u64 now;
s64 delta_exec;
if (curr->sched_class != &rt_sched_class)
return;
now = rq_clock_task(rq);
delta_exec = now - curr->se.exec_start;
if (unlikely((s64)delta_exec <= 0))
delta_exec = update_curr_common(rq);
if (unlikely(delta_exec <= 0))
return;
schedstat_set(curr->stats.exec_max,
max(curr->stats.exec_max, delta_exec));
trace_sched_stat_runtime(curr, delta_exec, 0);
update_current_exec_runtime(curr, now, delta_exec);
if (!rt_bandwidth_enabled())
return;

135
kernel/sched/sched.h
View File

@ -273,8 +273,6 @@ struct rt_bandwidth {
unsigned int rt_period_active;
};
void __dl_clear_params(struct task_struct *p);
static inline int dl_bandwidth_enabled(void)
{
return sysctl_sched_rt_runtime >= 0;
@ -315,6 +313,33 @@ extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *att
extern int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
extern int dl_bw_check_overflow(int cpu);
/*
* SCHED_DEADLINE supports servers (nested scheduling) with the following
* interface:
*
* dl_se::rq -- runqueue we belong to.
*
* dl_se::server_has_tasks() -- used on bandwidth enforcement; we 'stop' the
* server when it runs out of tasks to run.
*
* dl_se::server_pick() -- nested pick_next_task(); we yield the period if this
* returns NULL.
*
* dl_server_update() -- called from update_curr_common(), propagates runtime
* to the server.
*
* dl_server_start()
* dl_server_stop() -- start/stop the server when it has (no) tasks.
*
* dl_server_init() -- initializes the server.
*/
extern void dl_server_update(struct sched_dl_entity *dl_se, s64 delta_exec);
extern void dl_server_start(struct sched_dl_entity *dl_se);
extern void dl_server_stop(struct sched_dl_entity *dl_se);
extern void dl_server_init(struct sched_dl_entity *dl_se, struct rq *rq,
dl_server_has_tasks_f has_tasks,
dl_server_pick_f pick);
#ifdef CONFIG_CGROUP_SCHED
struct cfs_rq;
@ -2179,6 +2204,10 @@ extern const u32 sched_prio_to_wmult[40];
* MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
* in the runqueue.
*
* NOCLOCK - skip the update_rq_clock() (avoids double updates)
*
* MIGRATION - p->on_rq == TASK_ON_RQ_MIGRATING (used for DEADLINE)
*
* ENQUEUE_HEAD - place at front of runqueue (tail if not specified)
* ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
* ENQUEUE_MIGRATED - the task was migrated during wakeup
@ -2189,6 +2218,7 @@ extern const u32 sched_prio_to_wmult[40];
#define DEQUEUE_SAVE 0x02 /* Matches ENQUEUE_RESTORE */
#define DEQUEUE_MOVE 0x04 /* Matches ENQUEUE_MOVE */
#define DEQUEUE_NOCLOCK 0x08 /* Matches ENQUEUE_NOCLOCK */
#define DEQUEUE_MIGRATING 0x100 /* Matches ENQUEUE_MIGRATING */
#define ENQUEUE_WAKEUP 0x01
#define ENQUEUE_RESTORE 0x02
@ -2203,6 +2233,7 @@ extern const u32 sched_prio_to_wmult[40];
#define ENQUEUE_MIGRATED 0x00
#endif
#define ENQUEUE_INITIAL 0x80
#define ENQUEUE_MIGRATING 0x100
#define RETRY_TASK ((void *)-1UL)
@ -2212,6 +2243,8 @@ struct affinity_context {
unsigned int flags;
};
extern s64 update_curr_common(struct rq *rq);
struct sched_class {
#ifdef CONFIG_UCLAMP_TASK
@ -2425,8 +2458,7 @@ extern struct rt_bandwidth def_rt_bandwidth;
extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq);
extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
extern void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se);
extern void init_dl_entity(struct sched_dl_entity *dl_se);
#define BW_SHIFT 20
#define BW_UNIT (1 << BW_SHIFT)
@ -2822,6 +2854,7 @@ DEFINE_LOCK_GUARD_2(double_rq_lock, struct rq,
double_rq_lock(_T->lock, _T->lock2),
double_rq_unlock(_T->lock, _T->lock2))
extern struct sched_entity *__pick_root_entity(struct cfs_rq *cfs_rq);
extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
@ -2961,24 +2994,14 @@ static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
#endif
#ifdef CONFIG_SMP
/**
* enum cpu_util_type - CPU utilization type
* @FREQUENCY_UTIL: Utilization used to select frequency
* @ENERGY_UTIL: Utilization used during energy calculation
*
* The utilization signals of all scheduling classes (CFS/RT/DL) and IRQ time
* need to be aggregated differently depending on the usage made of them. This
* enum is used within effective_cpu_util() to differentiate the types of
* utilization expected by the callers, and adjust the aggregation accordingly.
*/
enum cpu_util_type {
FREQUENCY_UTIL,
ENERGY_UTIL,
};
unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
enum cpu_util_type type,
struct task_struct *p);
unsigned long *min,
unsigned long *max);
unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual,
unsigned long min,
unsigned long max);
/*
* Verify the fitness of task @p to run on @cpu taking into account the
@ -3035,59 +3058,6 @@ static inline bool uclamp_rq_is_idle(struct rq *rq)
return rq->uclamp_flags & UCLAMP_FLAG_IDLE;
}
/**
* uclamp_rq_util_with - clamp @util with @rq and @p effective uclamp values.
* @rq: The rq to clamp against. Must not be NULL.
* @util: The util value to clamp.
* @p: The task to clamp against. Can be NULL if you want to clamp
* against @rq only.
*
* Clamps the passed @util to the max(@rq, @p) effective uclamp values.
*
* If sched_uclamp_used static key is disabled, then just return the util
* without any clamping since uclamp aggregation at the rq level in the fast
* path is disabled, rendering this operation a NOP.
*
* Use uclamp_eff_value() if you don't care about uclamp values at rq level. It
* will return the correct effective uclamp value of the task even if the
* static key is disabled.
*/
static __always_inline
unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
struct task_struct *p)
{
unsigned long min_util = 0;
unsigned long max_util = 0;
if (!static_branch_likely(&sched_uclamp_used))
return util;
if (p) {
min_util = uclamp_eff_value(p, UCLAMP_MIN);
max_util = uclamp_eff_value(p, UCLAMP_MAX);
/*
* Ignore last runnable task's max clamp, as this task will
* reset it. Similarly, no need to read the rq's min clamp.
*/
if (uclamp_rq_is_idle(rq))
goto out;
}
min_util = max_t(unsigned long, min_util, uclamp_rq_get(rq, UCLAMP_MIN));
max_util = max_t(unsigned long, max_util, uclamp_rq_get(rq, UCLAMP_MAX));
out:
/*
* Since CPU's {min,max}_util clamps are MAX aggregated considering
* RUNNABLE tasks with _different_ clamps, we can end up with an
* inversion. Fix it now when the clamps are applied.
*/
if (unlikely(min_util >= max_util))
return min_util;
return clamp(util, min_util, max_util);
}
/* Is the rq being capped/throttled by uclamp_max? */
static inline bool uclamp_rq_is_capped(struct rq *rq)
{
@ -3125,13 +3095,6 @@ static inline unsigned long uclamp_eff_value(struct task_struct *p,
return SCHED_CAPACITY_SCALE;
}
static inline
unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
struct task_struct *p)
{
return util;
}
static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; }
static inline bool uclamp_is_used(void)
@ -3261,16 +3224,6 @@ extern int sched_dynamic_mode(const char *str);
extern void sched_dynamic_update(int mode);
#endif
static inline void update_current_exec_runtime(struct task_struct *curr,
u64 now, u64 delta_exec)
{
curr->se.sum_exec_runtime += delta_exec;
account_group_exec_runtime(curr, delta_exec);
curr->se.exec_start = now;
cgroup_account_cputime(curr, delta_exec);
}
#ifdef CONFIG_SCHED_MM_CID
#define SCHED_MM_CID_PERIOD_NS (100ULL * 1000000) /* 100ms */

13
kernel/sched/stop_task.c
View File

@ -70,18 +70,7 @@ static void yield_task_stop(struct rq *rq)
static void put_prev_task_stop(struct rq *rq, struct task_struct *prev)
{
struct task_struct *curr = rq->curr;
u64 now, delta_exec;
now = rq_clock_task(rq);
delta_exec = now - curr->se.exec_start;
if (unlikely((s64)delta_exec < 0))
delta_exec = 0;
schedstat_set(curr->stats.exec_max,
max(curr->stats.exec_max, delta_exec));
update_current_exec_runtime(curr, now, delta_exec);
update_curr_common(rq);
}
/*