Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched-fixes
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched-fixes: sched: default to n for GROUP_SCHED and FAIR_GROUP_SCHED sched: add optional support for CONFIG_HAVE_UNSTABLE_SCHED_CLOCK sched, x86: add HAVE_UNSTABLE_SCHED_CLOCK sched: fix cpu clock sched: fair-group: fix a Div0 error of the fair group scheduler sched: fix missing locking in sched_domains code sched: make clock sync tunable by architecture code sched: fix debugging sched: fix sched_info_switch not being called according to documentation sched: fix hrtick_start_fair and CPU-Hotplug sched: fix SCHED_FAIR wake-idle logic error sched: fix RT task-wakeup logic sched: add statics, don't return void expressions sched: add debug checks to idle functions sched: remove old sched doc sched: make rt_sched_class, idle_sched_class static sched: optimize calc_delta_mine() sched: fix normalized sleeper
This commit is contained in:
Linus Torvalds
Коммит
bb896afe20
|
|
@ -1,165 +0,0 @@
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|||
Goals, Design and Implementation of the
|
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new ultra-scalable O(1) scheduler
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This is an edited version of an email Ingo Molnar sent to
|
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lkml on 4 Jan 2002. It describes the goals, design, and
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implementation of Ingo's new ultra-scalable O(1) scheduler.
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Last Updated: 18 April 2002.
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Goal
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||||
====
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||||
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The main goal of the new scheduler is to keep all the good things we know
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and love about the current Linux scheduler:
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- good interactive performance even during high load: if the user
|
||||
types or clicks then the system must react instantly and must execute
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the user tasks smoothly, even during considerable background load.
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- good scheduling/wakeup performance with 1-2 runnable processes.
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- fairness: no process should stay without any timeslice for any
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unreasonable amount of time. No process should get an unjustly high
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amount of CPU time.
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- priorities: less important tasks can be started with lower priority,
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more important tasks with higher priority.
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- SMP efficiency: no CPU should stay idle if there is work to do.
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- SMP affinity: processes which run on one CPU should stay affine to
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that CPU. Processes should not bounce between CPUs too frequently.
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- plus additional scheduler features: RT scheduling, CPU binding.
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and the goal is also to add a few new things:
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- fully O(1) scheduling. Are you tired of the recalculation loop
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blowing the L1 cache away every now and then? Do you think the goodness
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loop is taking a bit too long to finish if there are lots of runnable
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processes? This new scheduler takes no prisoners: wakeup(), schedule(),
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the timer interrupt are all O(1) algorithms. There is no recalculation
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loop. There is no goodness loop either.
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- 'perfect' SMP scalability. With the new scheduler there is no 'big'
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runqueue_lock anymore - it's all per-CPU runqueues and locks - two
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tasks on two separate CPUs can wake up, schedule and context-switch
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completely in parallel, without any interlocking. All
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scheduling-relevant data is structured for maximum scalability.
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- better SMP affinity. The old scheduler has a particular weakness that
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causes the random bouncing of tasks between CPUs if/when higher
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priority/interactive tasks, this was observed and reported by many
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people. The reason is that the timeslice recalculation loop first needs
|
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every currently running task to consume its timeslice. But when this
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happens on eg. an 8-way system, then this property starves an
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increasing number of CPUs from executing any process. Once the last
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task that has a timeslice left has finished using up that timeslice,
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the recalculation loop is triggered and other CPUs can start executing
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tasks again - after having idled around for a number of timer ticks.
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The more CPUs, the worse this effect.
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|
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Furthermore, this same effect causes the bouncing effect as well:
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whenever there is such a 'timeslice squeeze' of the global runqueue,
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idle processors start executing tasks which are not affine to that CPU.
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(because the affine tasks have finished off their timeslices already.)
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|
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The new scheduler solves this problem by distributing timeslices on a
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per-CPU basis, without having any global synchronization or
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recalculation.
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|
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- batch scheduling. A significant proportion of computing-intensive tasks
|
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benefit from batch-scheduling, where timeslices are long and processes
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are roundrobin scheduled. The new scheduler does such batch-scheduling
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of the lowest priority tasks - so nice +19 jobs will get
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'batch-scheduled' automatically. With this scheduler, nice +19 jobs are
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in essence SCHED_IDLE, from an interactiveness point of view.
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- handle extreme loads more smoothly, without breakdown and scheduling
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storms.
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- O(1) RT scheduling. For those RT folks who are paranoid about the
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O(nr_running) property of the goodness loop and the recalculation loop.
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|
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- run fork()ed children before the parent. Andrea has pointed out the
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advantages of this a few months ago, but patches for this feature
|
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do not work with the old scheduler as well as they should,
|
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because idle processes often steal the new child before the fork()ing
|
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CPU gets to execute it.
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|
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|
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Design
|
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======
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The core of the new scheduler contains the following mechanisms:
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|
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- *two* priority-ordered 'priority arrays' per CPU. There is an 'active'
|
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array and an 'expired' array. The active array contains all tasks that
|
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are affine to this CPU and have timeslices left. The expired array
|
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contains all tasks which have used up their timeslices - but this array
|
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is kept sorted as well. The active and expired array is not accessed
|
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directly, it's accessed through two pointers in the per-CPU runqueue
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structure. If all active tasks are used up then we 'switch' the two
|
||||
pointers and from now on the ready-to-go (former-) expired array is the
|
||||
active array - and the empty active array serves as the new collector
|
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for expired tasks.
|
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|
||||
- there is a 64-bit bitmap cache for array indices. Finding the highest
|
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priority task is thus a matter of two x86 BSFL bit-search instructions.
|
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|
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the split-array solution enables us to have an arbitrary number of active
|
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and expired tasks, and the recalculation of timeslices can be done
|
||||
immediately when the timeslice expires. Because the arrays are always
|
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access through the pointers in the runqueue, switching the two arrays can
|
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be done very quickly.
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|
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this is a hybride priority-list approach coupled with roundrobin
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scheduling and the array-switch method of distributing timeslices.
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|
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- there is a per-task 'load estimator'.
|
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|
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one of the toughest things to get right is good interactive feel during
|
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heavy system load. While playing with various scheduler variants i found
|
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that the best interactive feel is achieved not by 'boosting' interactive
|
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tasks, but by 'punishing' tasks that want to use more CPU time than there
|
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is available. This method is also much easier to do in an O(1) fashion.
|
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|
||||
to establish the actual 'load' the task contributes to the system, a
|
||||
complex-looking but pretty accurate method is used: there is a 4-entry
|
||||
'history' ringbuffer of the task's activities during the last 4 seconds.
|
||||
This ringbuffer is operated without much overhead. The entries tell the
|
||||
scheduler a pretty accurate load-history of the task: has it used up more
|
||||
CPU time or less during the past N seconds. [the size '4' and the interval
|
||||
of 4x 1 seconds was found by lots of experimentation - this part is
|
||||
flexible and can be changed in both directions.]
|
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|
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the penalty a task gets for generating more load than the CPU can handle
|
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is a priority decrease - there is a maximum amount to this penalty
|
||||
relative to their static priority, so even fully CPU-bound tasks will
|
||||
observe each other's priorities, and will share the CPU accordingly.
|
||||
|
||||
the SMP load-balancer can be extended/switched with additional parallel
|
||||
computing and cache hierarchy concepts: NUMA scheduling, multi-core CPUs
|
||||
can be supported easily by changing the load-balancer. Right now it's
|
||||
tuned for my SMP systems.
|
||||
|
||||
i skipped the prev->mm == next->mm advantage - no workload i know of shows
|
||||
any sensitivity to this. It can be added back by sacrificing O(1)
|
||||
schedule() [the current and one-lower priority list can be searched for a
|
||||
that->mm == current->mm condition], but costs a fair number of cycles
|
||||
during a number of important workloads, so i wanted to avoid this as much
|
||||
as possible.
|
||||
|
||||
- the SMP idle-task startup code was still racy and the new scheduler
|
||||
triggered this. So i streamlined the idle-setup code a bit. We do not call
|
||||
into schedule() before all processors have started up fully and all idle
|
||||
threads are in place.
|
||||
|
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- the patch also cleans up a number of aspects of sched.c - moves code
|
||||
into other areas of the kernel where it's appropriate, and simplifies
|
||||
certain code paths and data constructs. As a result, the new scheduler's
|
||||
code is smaller than the old one.
|
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|
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Ingo
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|
|
@ -18,6 +18,7 @@ config X86_64
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### Arch settings
|
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config X86
|
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def_bool y
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select HAVE_UNSTABLE_SCHED_CLOCK
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select HAVE_IDE
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||||
select HAVE_OPROFILE
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select HAVE_KPROBES
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|
|
|
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|
|
@ -158,6 +158,8 @@ print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
|
|||
}
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#endif
|
||||
|
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extern unsigned long long time_sync_thresh;
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|
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/*
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* Task state bitmask. NOTE! These bits are also
|
||||
* encoded in fs/proc/array.c: get_task_state().
|
||||
|
|
@ -1551,6 +1553,35 @@ static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
|
|||
|
||||
extern unsigned long long sched_clock(void);
|
||||
|
||||
#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
|
||||
static inline void sched_clock_init(void)
|
||||
{
|
||||
}
|
||||
|
||||
static inline u64 sched_clock_cpu(int cpu)
|
||||
{
|
||||
return sched_clock();
|
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}
|
||||
|
||||
static inline void sched_clock_tick(void)
|
||||
{
|
||||
}
|
||||
|
||||
static inline void sched_clock_idle_sleep_event(void)
|
||||
{
|
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}
|
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|
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static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
|
||||
{
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}
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#else
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extern void sched_clock_init(void);
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extern u64 sched_clock_cpu(int cpu);
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extern void sched_clock_tick(void);
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extern void sched_clock_idle_sleep_event(void);
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extern void sched_clock_idle_wakeup_event(u64 delta_ns);
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#endif
|
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|
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/*
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* For kernel-internal use: high-speed (but slightly incorrect) per-cpu
|
||||
* clock constructed from sched_clock():
|
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|
|
@ -1977,6 +2008,11 @@ static inline void clear_tsk_need_resched(struct task_struct *tsk)
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clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
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}
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|
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static inline int test_tsk_need_resched(struct task_struct *tsk)
|
||||
{
|
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return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
|
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}
|
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|
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static inline int signal_pending(struct task_struct *p)
|
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{
|
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return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
|
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|
|
@ -1991,7 +2027,7 @@ static inline int fatal_signal_pending(struct task_struct *p)
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|
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static inline int need_resched(void)
|
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{
|
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return unlikely(test_thread_flag(TIF_NEED_RESCHED));
|
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return unlikely(test_tsk_need_resched(current));
|
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}
|
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|
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/*
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|
|
|
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11
init/Kconfig
11
init/Kconfig
|
|
@ -316,9 +316,16 @@ config CPUSETS
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|
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Say N if unsure.
|
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|
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#
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# Architectures with an unreliable sched_clock() should select this:
|
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#
|
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config HAVE_UNSTABLE_SCHED_CLOCK
|
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bool
|
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|
||||
config GROUP_SCHED
|
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bool "Group CPU scheduler"
|
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default y
|
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depends on EXPERIMENTAL
|
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default n
|
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help
|
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This feature lets CPU scheduler recognize task groups and control CPU
|
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bandwidth allocation to such task groups.
|
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|
|
@ -326,7 +333,7 @@ config GROUP_SCHED
|
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config FAIR_GROUP_SCHED
|
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bool "Group scheduling for SCHED_OTHER"
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depends on GROUP_SCHED
|
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default y
|
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default GROUP_SCHED
|
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|
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config RT_GROUP_SCHED
|
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bool "Group scheduling for SCHED_RR/FIFO"
|
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|
|
|
|||
|
|
@ -602,6 +602,7 @@ asmlinkage void __init start_kernel(void)
|
|||
softirq_init();
|
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timekeeping_init();
|
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time_init();
|
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sched_clock_init();
|
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profile_init();
|
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if (!irqs_disabled())
|
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printk("start_kernel(): bug: interrupts were enabled early\n");
|
||||
|
|
|
|||
|
|
@ -9,7 +9,7 @@ obj-y = sched.o fork.o exec_domain.o panic.o printk.o profile.o \
|
|||
rcupdate.o extable.o params.o posix-timers.o \
|
||||
kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o mutex.o \
|
||||
hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \
|
||||
notifier.o ksysfs.o pm_qos_params.o
|
||||
notifier.o ksysfs.o pm_qos_params.o sched_clock.o
|
||||
|
||||
obj-$(CONFIG_SYSCTL_SYSCALL_CHECK) += sysctl_check.o
|
||||
obj-$(CONFIG_STACKTRACE) += stacktrace.o
|
||||
|
|
|
|||
323
kernel/sched.c
323
kernel/sched.c
|
|
@ -74,16 +74,6 @@
|
|||
#include <asm/tlb.h>
|
||||
#include <asm/irq_regs.h>
|
||||
|
||||
/*
|
||||
* Scheduler clock - returns current time in nanosec units.
|
||||
* This is default implementation.
|
||||
* Architectures and sub-architectures can override this.
|
||||
*/
|
||||
unsigned long long __attribute__((weak)) sched_clock(void)
|
||||
{
|
||||
return (unsigned long long)jiffies * (NSEC_PER_SEC / HZ);
|
||||
}
|
||||
|
||||
/*
|
||||
* Convert user-nice values [ -20 ... 0 ... 19 ]
|
||||
* to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ],
|
||||
|
|
@ -242,6 +232,12 @@ static void destroy_rt_bandwidth(struct rt_bandwidth *rt_b)
|
|||
}
|
||||
#endif
|
||||
|
||||
/*
|
||||
* sched_domains_mutex serializes calls to arch_init_sched_domains,
|
||||
* detach_destroy_domains and partition_sched_domains.
|
||||
*/
|
||||
static DEFINE_MUTEX(sched_domains_mutex);
|
||||
|
||||
#ifdef CONFIG_GROUP_SCHED
|
||||
|
||||
#include <linux/cgroup.h>
|
||||
|
|
@ -308,9 +304,6 @@ static DEFINE_PER_CPU(struct rt_rq, init_rt_rq) ____cacheline_aligned_in_smp;
|
|||
*/
|
||||
static DEFINE_SPINLOCK(task_group_lock);
|
||||
|
||||
/* doms_cur_mutex serializes access to doms_cur[] array */
|
||||
static DEFINE_MUTEX(doms_cur_mutex);
|
||||
|
||||
#ifdef CONFIG_FAIR_GROUP_SCHED
|
||||
#ifdef CONFIG_USER_SCHED
|
||||
# define INIT_TASK_GROUP_LOAD (2*NICE_0_LOAD)
|
||||
|
|
@ -318,7 +311,13 @@ static DEFINE_MUTEX(doms_cur_mutex);
|
|||
# define INIT_TASK_GROUP_LOAD NICE_0_LOAD
|
||||
#endif
|
||||
|
||||
/*
|
||||
* A weight of 0, 1 or ULONG_MAX can cause arithmetics problems.
|
||||
* (The default weight is 1024 - so there's no practical
|
||||
* limitation from this.)
|
||||
*/
|
||||
#define MIN_SHARES 2
|
||||
#define MAX_SHARES (ULONG_MAX - 1)
|
||||
|
||||
static int init_task_group_load = INIT_TASK_GROUP_LOAD;
|
||||
#endif
|
||||
|
|
@ -358,21 +357,9 @@ static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
|
|||
#endif
|
||||
}
|
||||
|
||||
static inline void lock_doms_cur(void)
|
||||
{
|
||||
mutex_lock(&doms_cur_mutex);
|
||||
}
|
||||
|
||||
static inline void unlock_doms_cur(void)
|
||||
{
|
||||
mutex_unlock(&doms_cur_mutex);
|
||||
}
|
||||
|
||||
#else
|
||||
|
||||
static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
|
||||
static inline void lock_doms_cur(void) { }
|
||||
static inline void unlock_doms_cur(void) { }
|
||||
|
||||
#endif /* CONFIG_GROUP_SCHED */
|
||||
|
||||
|
|
@ -560,13 +547,7 @@ struct rq {
|
|||
unsigned long next_balance;
|
||||
struct mm_struct *prev_mm;
|
||||
|
||||
u64 clock, prev_clock_raw;
|
||||
s64 clock_max_delta;
|
||||
|
||||
unsigned int clock_warps, clock_overflows, clock_underflows;
|
||||
u64 idle_clock;
|
||||
unsigned int clock_deep_idle_events;
|
||||
u64 tick_timestamp;
|
||||
u64 clock;
|
||||
|
||||
atomic_t nr_iowait;
|
||||
|
||||
|
|
@ -631,82 +612,6 @@ static inline int cpu_of(struct rq *rq)
|
|||
#endif
|
||||
}
|
||||
|
||||
#ifdef CONFIG_NO_HZ
|
||||
static inline bool nohz_on(int cpu)
|
||||
{
|
||||
return tick_get_tick_sched(cpu)->nohz_mode != NOHZ_MODE_INACTIVE;
|
||||
}
|
||||
|
||||
static inline u64 max_skipped_ticks(struct rq *rq)
|
||||
{
|
||||
return nohz_on(cpu_of(rq)) ? jiffies - rq->last_tick_seen + 2 : 1;
|
||||
}
|
||||
|
||||
static inline void update_last_tick_seen(struct rq *rq)
|
||||
{
|
||||
rq->last_tick_seen = jiffies;
|
||||
}
|
||||
#else
|
||||
static inline u64 max_skipped_ticks(struct rq *rq)
|
||||
{
|
||||
return 1;
|
||||
}
|
||||
|
||||
static inline void update_last_tick_seen(struct rq *rq)
|
||||
{
|
||||
}
|
||||
#endif
|
||||
|
||||
/*
|
||||
* Update the per-runqueue clock, as finegrained as the platform can give
|
||||
* us, but without assuming monotonicity, etc.:
|
||||
*/
|
||||
static void __update_rq_clock(struct rq *rq)
|
||||
{
|
||||
u64 prev_raw = rq->prev_clock_raw;
|
||||
u64 now = sched_clock();
|
||||
s64 delta = now - prev_raw;
|
||||
u64 clock = rq->clock;
|
||||
|
||||
#ifdef CONFIG_SCHED_DEBUG
|
||||
WARN_ON_ONCE(cpu_of(rq) != smp_processor_id());
|
||||
#endif
|
||||
/*
|
||||
* Protect against sched_clock() occasionally going backwards:
|
||||
*/
|
||||
if (unlikely(delta < 0)) {
|
||||
clock++;
|
||||
rq->clock_warps++;
|
||||
} else {
|
||||
/*
|
||||
* Catch too large forward jumps too:
|
||||
*/
|
||||
u64 max_jump = max_skipped_ticks(rq) * TICK_NSEC;
|
||||
u64 max_time = rq->tick_timestamp + max_jump;
|
||||
|
||||
if (unlikely(clock + delta > max_time)) {
|
||||
if (clock < max_time)
|
||||
clock = max_time;
|
||||
else
|
||||
clock++;
|
||||
rq->clock_overflows++;
|
||||
} else {
|
||||
if (unlikely(delta > rq->clock_max_delta))
|
||||
rq->clock_max_delta = delta;
|
||||
clock += delta;
|
||||
}
|
||||
}
|
||||
|
||||
rq->prev_clock_raw = now;
|
||||
rq->clock = clock;
|
||||
}
|
||||
|
||||
static void update_rq_clock(struct rq *rq)
|
||||
{
|
||||
if (likely(smp_processor_id() == cpu_of(rq)))
|
||||
__update_rq_clock(rq);
|
||||
}
|
||||
|
||||
/*
|
||||
* The domain tree (rq->sd) is protected by RCU's quiescent state transition.
|
||||
* See detach_destroy_domains: synchronize_sched for details.
|
||||
|
|
@ -722,6 +627,11 @@ static void update_rq_clock(struct rq *rq)
|
|||
#define task_rq(p) cpu_rq(task_cpu(p))
|
||||
#define cpu_curr(cpu) (cpu_rq(cpu)->curr)
|
||||
|
||||
static inline void update_rq_clock(struct rq *rq)
|
||||
{
|
||||
rq->clock = sched_clock_cpu(cpu_of(rq));
|
||||
}
|
||||
|
||||
/*
|
||||
* Tunables that become constants when CONFIG_SCHED_DEBUG is off:
|
||||
*/
|
||||
|
|
@ -757,14 +667,14 @@ const_debug unsigned int sysctl_sched_features =
|
|||
#define SCHED_FEAT(name, enabled) \
|
||||
#name ,
|
||||
|
||||
__read_mostly char *sched_feat_names[] = {
|
||||
static __read_mostly char *sched_feat_names[] = {
|
||||
#include "sched_features.h"
|
||||
NULL
|
||||
};
|
||||
|
||||
#undef SCHED_FEAT
|
||||
|
||||
int sched_feat_open(struct inode *inode, struct file *filp)
|
||||
static int sched_feat_open(struct inode *inode, struct file *filp)
|
||||
{
|
||||
filp->private_data = inode->i_private;
|
||||
return 0;
|
||||
|
|
@ -899,7 +809,7 @@ static inline u64 global_rt_runtime(void)
|
|||
return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
|
||||
}
|
||||
|
||||
static const unsigned long long time_sync_thresh = 100000;
|
||||
unsigned long long time_sync_thresh = 100000;
|
||||
|
||||
static DEFINE_PER_CPU(unsigned long long, time_offset);
|
||||
static DEFINE_PER_CPU(unsigned long long, prev_cpu_time);
|
||||
|
|
@ -913,11 +823,14 @@ static DEFINE_PER_CPU(unsigned long long, prev_cpu_time);
|
|||
static DEFINE_SPINLOCK(time_sync_lock);
|
||||
static unsigned long long prev_global_time;
|
||||
|
||||
static unsigned long long __sync_cpu_clock(cycles_t time, int cpu)
|
||||
static unsigned long long __sync_cpu_clock(unsigned long long time, int cpu)
|
||||
{
|
||||
unsigned long flags;
|
||||
|
||||
spin_lock_irqsave(&time_sync_lock, flags);
|
||||
/*
|
||||
* We want this inlined, to not get tracer function calls
|
||||
* in this critical section:
|
||||
*/
|
||||
spin_acquire(&time_sync_lock.dep_map, 0, 0, _THIS_IP_);
|
||||
__raw_spin_lock(&time_sync_lock.raw_lock);
|
||||
|
||||
if (time < prev_global_time) {
|
||||
per_cpu(time_offset, cpu) += prev_global_time - time;
|
||||
|
|
@ -926,7 +839,8 @@ static unsigned long long __sync_cpu_clock(cycles_t time, int cpu)
|
|||
prev_global_time = time;
|
||||
}
|
||||
|
||||
spin_unlock_irqrestore(&time_sync_lock, flags);
|
||||
__raw_spin_unlock(&time_sync_lock.raw_lock);
|
||||
spin_release(&time_sync_lock.dep_map, 1, _THIS_IP_);
|
||||
|
||||
return time;
|
||||
}
|
||||
|
|
@ -934,8 +848,6 @@ static unsigned long long __sync_cpu_clock(cycles_t time, int cpu)
|
|||
static unsigned long long __cpu_clock(int cpu)
|
||||
{
|
||||
unsigned long long now;
|
||||
unsigned long flags;
|
||||
struct rq *rq;
|
||||
|
||||
/*
|
||||
* Only call sched_clock() if the scheduler has already been
|
||||
|
|
@ -944,11 +856,7 @@ static unsigned long long __cpu_clock(int cpu)
|
|||
if (unlikely(!scheduler_running))
|
||||
return 0;
|
||||
|
||||
local_irq_save(flags);
|
||||
rq = cpu_rq(cpu);
|
||||
update_rq_clock(rq);
|
||||
now = rq->clock;
|
||||
local_irq_restore(flags);
|
||||
now = sched_clock_cpu(cpu);
|
||||
|
||||
return now;
|
||||
}
|
||||
|
|
@ -960,13 +868,18 @@ static unsigned long long __cpu_clock(int cpu)
|
|||
unsigned long long cpu_clock(int cpu)
|
||||
{
|
||||
unsigned long long prev_cpu_time, time, delta_time;
|
||||
unsigned long flags;
|
||||
|
||||
local_irq_save(flags);
|
||||
prev_cpu_time = per_cpu(prev_cpu_time, cpu);
|
||||
time = __cpu_clock(cpu) + per_cpu(time_offset, cpu);
|
||||
delta_time = time-prev_cpu_time;
|
||||
|
||||
if (unlikely(delta_time > time_sync_thresh))
|
||||
if (unlikely(delta_time > time_sync_thresh)) {
|
||||
time = __sync_cpu_clock(time, cpu);
|
||||
per_cpu(prev_cpu_time, cpu) = time;
|
||||
}
|
||||
local_irq_restore(flags);
|
||||
|
||||
return time;
|
||||
}
|
||||
|
|
@ -1117,43 +1030,6 @@ static struct rq *this_rq_lock(void)
|
|||
return rq;
|
||||
}
|
||||
|
||||
/*
|
||||
* We are going deep-idle (irqs are disabled):
|
||||
*/
|
||||
void sched_clock_idle_sleep_event(void)
|
||||
{
|
||||
struct rq *rq = cpu_rq(smp_processor_id());
|
||||
|
||||
spin_lock(&rq->lock);
|
||||
__update_rq_clock(rq);
|
||||
spin_unlock(&rq->lock);
|
||||
rq->clock_deep_idle_events++;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(sched_clock_idle_sleep_event);
|
||||
|
||||
/*
|
||||
* We just idled delta nanoseconds (called with irqs disabled):
|
||||
*/
|
||||
void sched_clock_idle_wakeup_event(u64 delta_ns)
|
||||
{
|
||||
struct rq *rq = cpu_rq(smp_processor_id());
|
||||
u64 now = sched_clock();
|
||||
|
||||
rq->idle_clock += delta_ns;
|
||||
/*
|
||||
* Override the previous timestamp and ignore all
|
||||
* sched_clock() deltas that occured while we idled,
|
||||
* and use the PM-provided delta_ns to advance the
|
||||
* rq clock:
|
||||
*/
|
||||
spin_lock(&rq->lock);
|
||||
rq->prev_clock_raw = now;
|
||||
rq->clock += delta_ns;
|
||||
spin_unlock(&rq->lock);
|
||||
touch_softlockup_watchdog();
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event);
|
||||
|
||||
static void __resched_task(struct task_struct *p, int tif_bit);
|
||||
|
||||
static inline void resched_task(struct task_struct *p)
|
||||
|
|
@ -1189,6 +1065,7 @@ static inline void resched_rq(struct rq *rq)
|
|||
enum {
|
||||
HRTICK_SET, /* re-programm hrtick_timer */
|
||||
HRTICK_RESET, /* not a new slice */
|
||||
HRTICK_BLOCK, /* stop hrtick operations */
|
||||
};
|
||||
|
||||
/*
|
||||
|
|
@ -1200,6 +1077,8 @@ static inline int hrtick_enabled(struct rq *rq)
|
|||
{
|
||||
if (!sched_feat(HRTICK))
|
||||
return 0;
|
||||
if (unlikely(test_bit(HRTICK_BLOCK, &rq->hrtick_flags)))
|
||||
return 0;
|
||||
return hrtimer_is_hres_active(&rq->hrtick_timer);
|
||||
}
|
||||
|
||||
|
|
@ -1275,14 +1154,70 @@ static enum hrtimer_restart hrtick(struct hrtimer *timer)
|
|||
WARN_ON_ONCE(cpu_of(rq) != smp_processor_id());
|
||||
|
||||
spin_lock(&rq->lock);
|
||||
__update_rq_clock(rq);
|
||||
update_rq_clock(rq);
|
||||
rq->curr->sched_class->task_tick(rq, rq->curr, 1);
|
||||
spin_unlock(&rq->lock);
|
||||
|
||||
return HRTIMER_NORESTART;
|
||||
}
|
||||
|
||||
static inline void init_rq_hrtick(struct rq *rq)
|
||||
static void hotplug_hrtick_disable(int cpu)
|
||||
{
|
||||
struct rq *rq = cpu_rq(cpu);
|
||||
unsigned long flags;
|
||||
|
||||
spin_lock_irqsave(&rq->lock, flags);
|
||||
rq->hrtick_flags = 0;
|
||||
__set_bit(HRTICK_BLOCK, &rq->hrtick_flags);
|
||||
spin_unlock_irqrestore(&rq->lock, flags);
|
||||
|
||||
hrtick_clear(rq);
|
||||
}
|
||||
|
||||
static void hotplug_hrtick_enable(int cpu)
|
||||
{
|
||||
struct rq *rq = cpu_rq(cpu);
|
||||
unsigned long flags;
|
||||
|
||||
spin_lock_irqsave(&rq->lock, flags);
|
||||
__clear_bit(HRTICK_BLOCK, &rq->hrtick_flags);
|
||||
spin_unlock_irqrestore(&rq->lock, flags);
|
||||
}
|
||||
|
||||
static int
|
||||
hotplug_hrtick(struct notifier_block *nfb, unsigned long action, void *hcpu)
|
||||
{
|
||||
int cpu = (int)(long)hcpu;
|
||||
|
||||
switch (action) {
|
||||
case CPU_UP_CANCELED:
|
||||
case CPU_UP_CANCELED_FROZEN:
|
||||
case CPU_DOWN_PREPARE:
|
||||
case CPU_DOWN_PREPARE_FROZEN:
|
||||
case CPU_DEAD:
|
||||
case CPU_DEAD_FROZEN:
|
||||
hotplug_hrtick_disable(cpu);
|
||||
return NOTIFY_OK;
|
||||
|
||||
case CPU_UP_PREPARE:
|
||||
case CPU_UP_PREPARE_FROZEN:
|
||||
case CPU_DOWN_FAILED:
|
||||
case CPU_DOWN_FAILED_FROZEN:
|
||||
case CPU_ONLINE:
|
||||
case CPU_ONLINE_FROZEN:
|
||||
hotplug_hrtick_enable(cpu);
|
||||
return NOTIFY_OK;
|
||||
}
|
||||
|
||||
return NOTIFY_DONE;
|
||||
}
|
||||
|
||||
static void init_hrtick(void)
|
||||
{
|
||||
hotcpu_notifier(hotplug_hrtick, 0);
|
||||
}
|
||||
|
||||
static void init_rq_hrtick(struct rq *rq)
|
||||
{
|
||||
rq->hrtick_flags = 0;
|
||||
hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
|
||||
|
|
@ -1319,6 +1254,10 @@ static inline void init_rq_hrtick(struct rq *rq)
|
|||
void hrtick_resched(void)
|
||||
{
|
||||
}
|
||||
|
||||
static inline void init_hrtick(void)
|
||||
{
|
||||
}
|
||||
#endif
|
||||
|
||||
/*
|
||||
|
|
@ -1438,8 +1377,8 @@ calc_delta_mine(unsigned long delta_exec, unsigned long weight,
|
|||
{
|
||||
u64 tmp;
|
||||
|
||||
if (unlikely(!lw->inv_weight))
|
||||
lw->inv_weight = (WMULT_CONST-lw->weight/2) / (lw->weight+1);
|
||||
if (!lw->inv_weight)
|
||||
lw->inv_weight = 1 + (WMULT_CONST-lw->weight/2)/(lw->weight+1);
|
||||
|
||||
tmp = (u64)delta_exec * weight;
|
||||
/*
|
||||
|
|
@ -1748,6 +1687,8 @@ __update_group_shares_cpu(struct task_group *tg, struct sched_domain *sd,
|
|||
|
||||
if (shares < MIN_SHARES)
|
||||
shares = MIN_SHARES;
|
||||
else if (shares > MAX_SHARES)
|
||||
shares = MAX_SHARES;
|
||||
|
||||
__set_se_shares(tg->se[tcpu], shares);
|
||||
}
|
||||
|
|
@ -4339,8 +4280,10 @@ void account_system_time(struct task_struct *p, int hardirq_offset,
|
|||
struct rq *rq = this_rq();
|
||||
cputime64_t tmp;
|
||||
|
||||
if ((p->flags & PF_VCPU) && (irq_count() - hardirq_offset == 0))
|
||||
return account_guest_time(p, cputime);
|
||||
if ((p->flags & PF_VCPU) && (irq_count() - hardirq_offset == 0)) {
|
||||
account_guest_time(p, cputime);
|
||||
return;
|
||||
}
|
||||
|
||||
p->stime = cputime_add(p->stime, cputime);
|
||||
|
||||
|
|
@ -4404,19 +4347,11 @@ void scheduler_tick(void)
|
|||
int cpu = smp_processor_id();
|
||||
struct rq *rq = cpu_rq(cpu);
|
||||
struct task_struct *curr = rq->curr;
|
||||
u64 next_tick = rq->tick_timestamp + TICK_NSEC;
|
||||
|
||||
sched_clock_tick();
|
||||
|
||||
spin_lock(&rq->lock);
|
||||
__update_rq_clock(rq);
|
||||
/*
|
||||
* Let rq->clock advance by at least TICK_NSEC:
|
||||
*/
|
||||
if (unlikely(rq->clock < next_tick)) {
|
||||
rq->clock = next_tick;
|
||||
rq->clock_underflows++;
|
||||
}
|
||||
rq->tick_timestamp = rq->clock;
|
||||
update_last_tick_seen(rq);
|
||||
update_rq_clock(rq);
|
||||
update_cpu_load(rq);
|
||||
curr->sched_class->task_tick(rq, curr, 0);
|
||||
spin_unlock(&rq->lock);
|
||||
|
|
@ -4570,7 +4505,7 @@ need_resched_nonpreemptible:
|
|||
* Do the rq-clock update outside the rq lock:
|
||||
*/
|
||||
local_irq_disable();
|
||||
__update_rq_clock(rq);
|
||||
update_rq_clock(rq);
|
||||
spin_lock(&rq->lock);
|
||||
clear_tsk_need_resched(prev);
|
||||
|
||||
|
|
@ -4595,9 +4530,9 @@ need_resched_nonpreemptible:
|
|||
prev->sched_class->put_prev_task(rq, prev);
|
||||
next = pick_next_task(rq, prev);
|
||||
|
||||
sched_info_switch(prev, next);
|
||||
|
||||
if (likely(prev != next)) {
|
||||
sched_info_switch(prev, next);
|
||||
|
||||
rq->nr_switches++;
|
||||
rq->curr = next;
|
||||
++*switch_count;
|
||||
|
|
@ -7755,7 +7690,7 @@ void partition_sched_domains(int ndoms_new, cpumask_t *doms_new,
|
|||
{
|
||||
int i, j;
|
||||
|
||||
lock_doms_cur();
|
||||
mutex_lock(&sched_domains_mutex);
|
||||
|
||||
/* always unregister in case we don't destroy any domains */
|
||||
unregister_sched_domain_sysctl();
|
||||
|
|
@ -7804,7 +7739,7 @@ match2:
|
|||
|
||||
register_sched_domain_sysctl();
|
||||
|
||||
unlock_doms_cur();
|
||||
mutex_unlock(&sched_domains_mutex);
|
||||
}
|
||||
|
||||
#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
|
||||
|
|
@ -7813,8 +7748,10 @@ int arch_reinit_sched_domains(void)
|
|||
int err;
|
||||
|
||||
get_online_cpus();
|
||||
mutex_lock(&sched_domains_mutex);
|
||||
detach_destroy_domains(&cpu_online_map);
|
||||
err = arch_init_sched_domains(&cpu_online_map);
|
||||
mutex_unlock(&sched_domains_mutex);
|
||||
put_online_cpus();
|
||||
|
||||
return err;
|
||||
|
|
@ -7932,13 +7869,16 @@ void __init sched_init_smp(void)
|
|||
BUG_ON(sched_group_nodes_bycpu == NULL);
|
||||
#endif
|
||||
get_online_cpus();
|
||||
mutex_lock(&sched_domains_mutex);
|
||||
arch_init_sched_domains(&cpu_online_map);
|
||||
cpus_andnot(non_isolated_cpus, cpu_possible_map, cpu_isolated_map);
|
||||
if (cpus_empty(non_isolated_cpus))
|
||||
cpu_set(smp_processor_id(), non_isolated_cpus);
|
||||
mutex_unlock(&sched_domains_mutex);
|
||||
put_online_cpus();
|
||||
/* XXX: Theoretical race here - CPU may be hotplugged now */
|
||||
hotcpu_notifier(update_sched_domains, 0);
|
||||
init_hrtick();
|
||||
|
||||
/* Move init over to a non-isolated CPU */
|
||||
if (set_cpus_allowed_ptr(current, &non_isolated_cpus) < 0)
|
||||
|
|
@ -8025,7 +7965,7 @@ static void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
|
|||
|
||||
se->my_q = cfs_rq;
|
||||
se->load.weight = tg->shares;
|
||||
se->load.inv_weight = div64_u64(1ULL<<32, se->load.weight);
|
||||
se->load.inv_weight = 0;
|
||||
se->parent = parent;
|
||||
}
|
||||
#endif
|
||||
|
|
@ -8149,8 +8089,6 @@ void __init sched_init(void)
|
|||
spin_lock_init(&rq->lock);
|
||||
lockdep_set_class(&rq->lock, &rq->rq_lock_key);
|
||||
rq->nr_running = 0;
|
||||
rq->clock = 1;
|
||||
update_last_tick_seen(rq);
|
||||
init_cfs_rq(&rq->cfs, rq);
|
||||
init_rt_rq(&rq->rt, rq);
|
||||
#ifdef CONFIG_FAIR_GROUP_SCHED
|
||||
|
|
@ -8294,6 +8232,7 @@ EXPORT_SYMBOL(__might_sleep);
|
|||
static void normalize_task(struct rq *rq, struct task_struct *p)
|
||||
{
|
||||
int on_rq;
|
||||
|
||||
update_rq_clock(rq);
|
||||
on_rq = p->se.on_rq;
|
||||
if (on_rq)
|
||||
|
|
@ -8325,7 +8264,6 @@ void normalize_rt_tasks(void)
|
|||
p->se.sleep_start = 0;
|
||||
p->se.block_start = 0;
|
||||
#endif
|
||||
task_rq(p)->clock = 0;
|
||||
|
||||
if (!rt_task(p)) {
|
||||
/*
|
||||
|
|
@ -8692,7 +8630,7 @@ static void __set_se_shares(struct sched_entity *se, unsigned long shares)
|
|||
dequeue_entity(cfs_rq, se, 0);
|
||||
|
||||
se->load.weight = shares;
|
||||
se->load.inv_weight = div64_u64((1ULL<<32), shares);
|
||||
se->load.inv_weight = 0;
|
||||
|
||||
if (on_rq)
|
||||
enqueue_entity(cfs_rq, se, 0);
|
||||
|
|
@ -8722,13 +8660,10 @@ int sched_group_set_shares(struct task_group *tg, unsigned long shares)
|
|||
if (!tg->se[0])
|
||||
return -EINVAL;
|
||||
|
||||
/*
|
||||
* A weight of 0 or 1 can cause arithmetics problems.
|
||||
* (The default weight is 1024 - so there's no practical
|
||||
* limitation from this.)
|
||||
*/
|
||||
if (shares < MIN_SHARES)
|
||||
shares = MIN_SHARES;
|
||||
else if (shares > MAX_SHARES)
|
||||
shares = MAX_SHARES;
|
||||
|
||||
mutex_lock(&shares_mutex);
|
||||
if (tg->shares == shares)
|
||||
|
|
@ -8753,7 +8688,7 @@ int sched_group_set_shares(struct task_group *tg, unsigned long shares)
|
|||
* force a rebalance
|
||||
*/
|
||||
cfs_rq_set_shares(tg->cfs_rq[i], 0);
|
||||
set_se_shares(tg->se[i], shares/nr_cpu_ids);
|
||||
set_se_shares(tg->se[i], shares);
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
|
|||
|
|
@ -0,0 +1,236 @@
|
|||
/*
|
||||
* sched_clock for unstable cpu clocks
|
||||
*
|
||||
* Copyright (C) 2008 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
|
||||
*
|
||||
* Based on code by:
|
||||
* Ingo Molnar <mingo@redhat.com>
|
||||
* Guillaume Chazarain <guichaz@gmail.com>
|
||||
*
|
||||
* Create a semi stable clock from a mixture of other events, including:
|
||||
* - gtod
|
||||
* - jiffies
|
||||
* - sched_clock()
|
||||
* - explicit idle events
|
||||
*
|
||||
* We use gtod as base and the unstable clock deltas. The deltas are filtered,
|
||||
* making it monotonic and keeping it within an expected window. This window
|
||||
* is set up using jiffies.
|
||||
*
|
||||
* Furthermore, explicit sleep and wakeup hooks allow us to account for time
|
||||
* that is otherwise invisible (TSC gets stopped).
|
||||
*
|
||||
* The clock: sched_clock_cpu() is monotonic per cpu, and should be somewhat
|
||||
* consistent between cpus (never more than 1 jiffies difference).
|
||||
*/
|
||||
#include <linux/sched.h>
|
||||
#include <linux/percpu.h>
|
||||
#include <linux/spinlock.h>
|
||||
#include <linux/ktime.h>
|
||||
#include <linux/module.h>
|
||||
|
||||
|
||||
#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
|
||||
|
||||
struct sched_clock_data {
|
||||
/*
|
||||
* Raw spinlock - this is a special case: this might be called
|
||||
* from within instrumentation code so we dont want to do any
|
||||
* instrumentation ourselves.
|
||||
*/
|
||||
raw_spinlock_t lock;
|
||||
|
||||
unsigned long prev_jiffies;
|
||||
u64 prev_raw;
|
||||
u64 tick_raw;
|
||||
u64 tick_gtod;
|
||||
u64 clock;
|
||||
};
|
||||
|
||||
static DEFINE_PER_CPU_SHARED_ALIGNED(struct sched_clock_data, sched_clock_data);
|
||||
|
||||
static inline struct sched_clock_data *this_scd(void)
|
||||
{
|
||||
return &__get_cpu_var(sched_clock_data);
|
||||
}
|
||||
|
||||
static inline struct sched_clock_data *cpu_sdc(int cpu)
|
||||
{
|
||||
return &per_cpu(sched_clock_data, cpu);
|
||||
}
|
||||
|
||||
void sched_clock_init(void)
|
||||
{
|
||||
u64 ktime_now = ktime_to_ns(ktime_get());
|
||||
u64 now = 0;
|
||||
int cpu;
|
||||
|
||||
for_each_possible_cpu(cpu) {
|
||||
struct sched_clock_data *scd = cpu_sdc(cpu);
|
||||
|
||||
scd->lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
|
||||
scd->prev_jiffies = jiffies;
|
||||
scd->prev_raw = now;
|
||||
scd->tick_raw = now;
|
||||
scd->tick_gtod = ktime_now;
|
||||
scd->clock = ktime_now;
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* update the percpu scd from the raw @now value
|
||||
*
|
||||
* - filter out backward motion
|
||||
* - use jiffies to generate a min,max window to clip the raw values
|
||||
*/
|
||||
static void __update_sched_clock(struct sched_clock_data *scd, u64 now)
|
||||
{
|
||||
unsigned long now_jiffies = jiffies;
|
||||
long delta_jiffies = now_jiffies - scd->prev_jiffies;
|
||||
u64 clock = scd->clock;
|
||||
u64 min_clock, max_clock;
|
||||
s64 delta = now - scd->prev_raw;
|
||||
|
||||
WARN_ON_ONCE(!irqs_disabled());
|
||||
min_clock = scd->tick_gtod + delta_jiffies * TICK_NSEC;
|
||||
|
||||
if (unlikely(delta < 0)) {
|
||||
clock++;
|
||||
goto out;
|
||||
}
|
||||
|
||||
max_clock = min_clock + TICK_NSEC;
|
||||
|
||||
if (unlikely(clock + delta > max_clock)) {
|
||||
if (clock < max_clock)
|
||||
clock = max_clock;
|
||||
else
|
||||
clock++;
|
||||
} else {
|
||||
clock += delta;
|
||||
}
|
||||
|
||||
out:
|
||||
if (unlikely(clock < min_clock))
|
||||
clock = min_clock;
|
||||
|
||||
scd->prev_raw = now;
|
||||
scd->prev_jiffies = now_jiffies;
|
||||
scd->clock = clock;
|
||||
}
|
||||
|
||||
static void lock_double_clock(struct sched_clock_data *data1,
|
||||
struct sched_clock_data *data2)
|
||||
{
|
||||
if (data1 < data2) {
|
||||
__raw_spin_lock(&data1->lock);
|
||||
__raw_spin_lock(&data2->lock);
|
||||
} else {
|
||||
__raw_spin_lock(&data2->lock);
|
||||
__raw_spin_lock(&data1->lock);
|
||||
}
|
||||
}
|
||||
|
||||
u64 sched_clock_cpu(int cpu)
|
||||
{
|
||||
struct sched_clock_data *scd = cpu_sdc(cpu);
|
||||
u64 now, clock;
|
||||
|
||||
WARN_ON_ONCE(!irqs_disabled());
|
||||
now = sched_clock();
|
||||
|
||||
if (cpu != raw_smp_processor_id()) {
|
||||
/*
|
||||
* in order to update a remote cpu's clock based on our
|
||||
* unstable raw time rebase it against:
|
||||
* tick_raw (offset between raw counters)
|
||||
* tick_gotd (tick offset between cpus)
|
||||
*/
|
||||
struct sched_clock_data *my_scd = this_scd();
|
||||
|
||||
lock_double_clock(scd, my_scd);
|
||||
|
||||
now -= my_scd->tick_raw;
|
||||
now += scd->tick_raw;
|
||||
|
||||
now -= my_scd->tick_gtod;
|
||||
now += scd->tick_gtod;
|
||||
|
||||
__raw_spin_unlock(&my_scd->lock);
|
||||
} else {
|
||||
__raw_spin_lock(&scd->lock);
|
||||
}
|
||||
|
||||
__update_sched_clock(scd, now);
|
||||
clock = scd->clock;
|
||||
|
||||
__raw_spin_unlock(&scd->lock);
|
||||
|
||||
return clock;
|
||||
}
|
||||
|
||||
void sched_clock_tick(void)
|
||||
{
|
||||
struct sched_clock_data *scd = this_scd();
|
||||
u64 now, now_gtod;
|
||||
|
||||
WARN_ON_ONCE(!irqs_disabled());
|
||||
|
||||
now = sched_clock();
|
||||
now_gtod = ktime_to_ns(ktime_get());
|
||||
|
||||
__raw_spin_lock(&scd->lock);
|
||||
__update_sched_clock(scd, now);
|
||||
/*
|
||||
* update tick_gtod after __update_sched_clock() because that will
|
||||
* already observe 1 new jiffy; adding a new tick_gtod to that would
|
||||
* increase the clock 2 jiffies.
|
||||
*/
|
||||
scd->tick_raw = now;
|
||||
scd->tick_gtod = now_gtod;
|
||||
__raw_spin_unlock(&scd->lock);
|
||||
}
|
||||
|
||||
/*
|
||||
* We are going deep-idle (irqs are disabled):
|
||||
*/
|
||||
void sched_clock_idle_sleep_event(void)
|
||||
{
|
||||
sched_clock_cpu(smp_processor_id());
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(sched_clock_idle_sleep_event);
|
||||
|
||||
/*
|
||||
* We just idled delta nanoseconds (called with irqs disabled):
|
||||
*/
|
||||
void sched_clock_idle_wakeup_event(u64 delta_ns)
|
||||
{
|
||||
struct sched_clock_data *scd = this_scd();
|
||||
u64 now = sched_clock();
|
||||
|
||||
/*
|
||||
* Override the previous timestamp and ignore all
|
||||
* sched_clock() deltas that occured while we idled,
|
||||
* and use the PM-provided delta_ns to advance the
|
||||
* rq clock:
|
||||
*/
|
||||
__raw_spin_lock(&scd->lock);
|
||||
scd->prev_raw = now;
|
||||
scd->clock += delta_ns;
|
||||
__raw_spin_unlock(&scd->lock);
|
||||
|
||||
touch_softlockup_watchdog();
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event);
|
||||
|
||||
#endif
|
||||
|
||||
/*
|
||||
* Scheduler clock - returns current time in nanosec units.
|
||||
* This is default implementation.
|
||||
* Architectures and sub-architectures can override this.
|
||||
*/
|
||||
unsigned long long __attribute__((weak)) sched_clock(void)
|
||||
{
|
||||
return (unsigned long long)jiffies * (NSEC_PER_SEC / HZ);
|
||||
}
|
||||
|
|
@ -204,13 +204,6 @@ static void print_cpu(struct seq_file *m, int cpu)
|
|||
PN(next_balance);
|
||||
P(curr->pid);
|
||||
PN(clock);
|
||||
PN(idle_clock);
|
||||
PN(prev_clock_raw);
|
||||
P(clock_warps);
|
||||
P(clock_overflows);
|
||||
P(clock_underflows);
|
||||
P(clock_deep_idle_events);
|
||||
PN(clock_max_delta);
|
||||
P(cpu_load[0]);
|
||||
P(cpu_load[1]);
|
||||
P(cpu_load[2]);
|
||||
|
|
|
|||
|
|
@ -682,6 +682,7 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int wakeup)
|
|||
* Update run-time statistics of the 'current'.
|
||||
*/
|
||||
update_curr(cfs_rq);
|
||||
account_entity_enqueue(cfs_rq, se);
|
||||
|
||||
if (wakeup) {
|
||||
place_entity(cfs_rq, se, 0);
|
||||
|
|
@ -692,7 +693,6 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int wakeup)
|
|||
check_spread(cfs_rq, se);
|
||||
if (se != cfs_rq->curr)
|
||||
__enqueue_entity(cfs_rq, se);
|
||||
account_entity_enqueue(cfs_rq, se);
|
||||
}
|
||||
|
||||
static void update_avg(u64 *avg, u64 sample)
|
||||
|
|
@ -841,8 +841,10 @@ entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr, int queued)
|
|||
* queued ticks are scheduled to match the slice, so don't bother
|
||||
* validating it and just reschedule.
|
||||
*/
|
||||
if (queued)
|
||||
return resched_task(rq_of(cfs_rq)->curr);
|
||||
if (queued) {
|
||||
resched_task(rq_of(cfs_rq)->curr);
|
||||
return;
|
||||
}
|
||||
/*
|
||||
* don't let the period tick interfere with the hrtick preemption
|
||||
*/
|
||||
|
|
@ -957,7 +959,7 @@ static void yield_task_fair(struct rq *rq)
|
|||
return;
|
||||
|
||||
if (likely(!sysctl_sched_compat_yield) && curr->policy != SCHED_BATCH) {
|
||||
__update_rq_clock(rq);
|
||||
update_rq_clock(rq);
|
||||
/*
|
||||
* Update run-time statistics of the 'current'.
|
||||
*/
|
||||
|
|
@ -1007,7 +1009,7 @@ static int wake_idle(int cpu, struct task_struct *p)
|
|||
* sibling runqueue info. This will avoid the checks and cache miss
|
||||
* penalities associated with that.
|
||||
*/
|
||||
if (idle_cpu(cpu) || cpu_rq(cpu)->nr_running > 1)
|
||||
if (idle_cpu(cpu) || cpu_rq(cpu)->cfs.nr_running > 1)
|
||||
return cpu;
|
||||
|
||||
for_each_domain(cpu, sd) {
|
||||
|
|
@ -1611,30 +1613,6 @@ static const struct sched_class fair_sched_class = {
|
|||
};
|
||||
|
||||
#ifdef CONFIG_SCHED_DEBUG
|
||||
static void
|
||||
print_cfs_rq_tasks(struct seq_file *m, struct cfs_rq *cfs_rq, int depth)
|
||||
{
|
||||
struct sched_entity *se;
|
||||
|
||||
if (!cfs_rq)
|
||||
return;
|
||||
|
||||
list_for_each_entry_rcu(se, &cfs_rq->tasks, group_node) {
|
||||
int i;
|
||||
|
||||
for (i = depth; i; i--)
|
||||
seq_puts(m, " ");
|
||||
|
||||
seq_printf(m, "%lu %s %lu\n",
|
||||
se->load.weight,
|
||||
entity_is_task(se) ? "T" : "G",
|
||||
calc_delta_weight(SCHED_LOAD_SCALE, se)
|
||||
);
|
||||
if (!entity_is_task(se))
|
||||
print_cfs_rq_tasks(m, group_cfs_rq(se), depth + 1);
|
||||
}
|
||||
}
|
||||
|
||||
static void print_cfs_stats(struct seq_file *m, int cpu)
|
||||
{
|
||||
struct cfs_rq *cfs_rq;
|
||||
|
|
@ -1642,9 +1620,6 @@ static void print_cfs_stats(struct seq_file *m, int cpu)
|
|||
rcu_read_lock();
|
||||
for_each_leaf_cfs_rq(cpu_rq(cpu), cfs_rq)
|
||||
print_cfs_rq(m, cpu, cfs_rq);
|
||||
|
||||
seq_printf(m, "\nWeight tree:\n");
|
||||
print_cfs_rq_tasks(m, &cpu_rq(cpu)->cfs, 1);
|
||||
rcu_read_unlock();
|
||||
}
|
||||
#endif
|
||||
|
|
|
|||
|
|
@ -99,7 +99,7 @@ static void prio_changed_idle(struct rq *rq, struct task_struct *p,
|
|||
/*
|
||||
* Simple, special scheduling class for the per-CPU idle tasks:
|
||||
*/
|
||||
const struct sched_class idle_sched_class = {
|
||||
static const struct sched_class idle_sched_class = {
|
||||
/* .next is NULL */
|
||||
/* no enqueue/yield_task for idle tasks */
|
||||
|
||||
|
|
|
|||
|
|
@ -1098,11 +1098,14 @@ static void post_schedule_rt(struct rq *rq)
|
|||
}
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* If we are not running and we are not going to reschedule soon, we should
|
||||
* try to push tasks away now
|
||||
*/
|
||||
static void task_wake_up_rt(struct rq *rq, struct task_struct *p)
|
||||
{
|
||||
if (!task_running(rq, p) &&
|
||||
(p->prio >= rq->rt.highest_prio) &&
|
||||
!test_tsk_need_resched(rq->curr) &&
|
||||
rq->rt.overloaded)
|
||||
push_rt_tasks(rq);
|
||||
}
|
||||
|
|
@ -1309,7 +1312,7 @@ static void set_curr_task_rt(struct rq *rq)
|
|||
p->se.exec_start = rq->clock;
|
||||
}
|
||||
|
||||
const struct sched_class rt_sched_class = {
|
||||
static const struct sched_class rt_sched_class = {
|
||||
.next = &fair_sched_class,
|
||||
.enqueue_task = enqueue_task_rt,
|
||||
.dequeue_task = dequeue_task_rt,
|
||||
|
|
|
|||
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