Commit 828cad8e authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull scheduler updates from Ingo Molnar:
 "The main changes in this (fairly busy) cycle were:

   - There was a class of scheduler bugs related to forgetting to update
     the rq-clock timestamp which can cause weird and hard to debug
     problems, so there's a new debug facility for this: which uncovered
     a whole lot of bugs which convinced us that we want to keep the
     debug facility.

     (Peter Zijlstra, Matt Fleming)

   - Various cputime related updates: eliminate cputime and use u64
     nanoseconds directly, simplify and improve the arch interfaces,
     implement delayed accounting more widely, etc. - (Frederic
     Weisbecker)

   - Move code around for better structure plus cleanups (Ingo Molnar)

   - Move IO schedule accounting deeper into the scheduler plus related
     changes to improve the situation (Tejun Heo)

   - ... plus a round of sched/rt and sched/deadline fixes, plus other
     fixes, updats and cleanups"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (85 commits)
  sched/core: Remove unlikely() annotation from sched_move_task()
  sched/autogroup: Rename auto_group.[ch] to autogroup.[ch]
  sched/topology: Split out scheduler topology code from core.c into topology.c
  sched/core: Remove unnecessary #include headers
  sched/rq_clock: Consolidate the ordering of the rq_clock methods
  delayacct: Include <uapi/linux/taskstats.h>
  sched/core: Clean up comments
  sched/rt: Show the 'sched_rr_timeslice' SCHED_RR timeslice tuning knob in milliseconds
  sched/clock: Add dummy clear_sched_clock_stable() stub function
  sched/cputime: Remove generic asm headers
  sched/cputime: Remove unused nsec_to_cputime()
  s390, sched/cputime: Remove unused cputime definitions
  powerpc, sched/cputime: Remove unused cputime definitions
  s390, sched/cputime: Make arch_cpu_idle_time() to return nsecs
  ia64, sched/cputime: Remove unused cputime definitions
  ia64: Convert vtime to use nsec units directly
  ia64, sched/cputime: Move the nsecs based cputime headers to the last arch using it
  sched/cputime: Remove jiffies based cputime
  sched/cputime, vtime: Return nsecs instead of cputime_t to account
  sched/cputime: Complete nsec conversion of tick based accounting
  ...
parents 60c906ba bb3bac2c

Documentation/scheduler/sched-deadline.txt

+6 −0
Original line number Diff line number Diff line
@@ -408,6 +408,11 @@ CONTENTS 
  * the new scheduling related syscalls that manipulate it, i.e.,

    sched_setattr() and sched_getattr() are implemented.



 For debugging purposes, the leftover runtime and absolute deadline of a

 SCHED_DEADLINE task can be retrieved through /proc/<pid>/sched (entries

 dl.runtime and dl.deadline, both values in ns). A programmatic way to

 retrieve these values from production code is under discussion.





4.3 Default behavior

---------------------
@@ -476,6 +481,7 @@ CONTENTS 


 Still missing:



  - programmatic way to retrieve current runtime and absolute deadline

  - refinements to deadline inheritance, especially regarding the possibility

    of retaining bandwidth isolation among non-interacting tasks. This is

    being studied from both theoretical and practical points of view, and

Documentation/scheduler/sched-rt-group.txt

+4 −4
Original line number Diff line number Diff line
@@ -158,11 +158,11 @@ as its prone to starvation without deadline scheduling. 
Consider two sibling groups A and B; both have 50% bandwidth, but A's

period is twice the length of B's.



* group A: period=100000us, runtime=10000us

	- this runs for 0.01s once every 0.1s

* group A: period=100000us, runtime=50000us

	- this runs for 0.05s once every 0.1s



* group B: period= 50000us, runtime=10000us

	- this runs for 0.01s twice every 0.1s (or once every 0.05 sec).

* group B: period= 50000us, runtime=25000us

	- this runs for 0.025s twice every 0.1s (or once every 0.05 sec).



This means that currently a while (1) loop in A will run for the full period of

B and can starve B's tasks (assuming they are of lower priority) for a whole

arch/alpha/include/asm/Kbuild

+0 −1
Original line number Diff line number Diff line 




generic-y += clkdev.h

generic-y += cputime.h

generic-y += exec.h

generic-y += export.h

generic-y += irq_work.h

arch/alpha/kernel/osf_sys.c

+5 −5
Original line number Diff line number Diff line
@@ -1145,7 +1145,7 @@ struct rusage32 { 
SYSCALL_DEFINE2(osf_getrusage, int, who, struct rusage32 __user *, ru)

{

	struct rusage32 r;

	cputime_t utime, stime;

	u64 utime, stime;

	unsigned long utime_jiffies, stime_jiffies;



	if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN)
@@ -1155,16 +1155,16 @@ SYSCALL_DEFINE2(osf_getrusage, int, who, struct rusage32 __user *, ru) 
	switch (who) {

	case RUSAGE_SELF:

		task_cputime(current, &utime, &stime);

		utime_jiffies = cputime_to_jiffies(utime);

		stime_jiffies = cputime_to_jiffies(stime);

		utime_jiffies = nsecs_to_jiffies(utime);

		stime_jiffies = nsecs_to_jiffies(stime);

		jiffies_to_timeval32(utime_jiffies, &r.ru_utime);

		jiffies_to_timeval32(stime_jiffies, &r.ru_stime);

		r.ru_minflt = current->min_flt;

		r.ru_majflt = current->maj_flt;

		break;

	case RUSAGE_CHILDREN:

		utime_jiffies = cputime_to_jiffies(current->signal->cutime);

		stime_jiffies = cputime_to_jiffies(current->signal->cstime);

		utime_jiffies = nsecs_to_jiffies(current->signal->cutime);

		stime_jiffies = nsecs_to_jiffies(current->signal->cstime);

		jiffies_to_timeval32(utime_jiffies, &r.ru_utime);

		jiffies_to_timeval32(stime_jiffies, &r.ru_stime);

		r.ru_minflt = current->signal->cmin_flt;

arch/arc/include/asm/Kbuild

+0 −1
Original line number Diff line number Diff line
@@ -2,7 +2,6 @@ generic-y += auxvec.h 
generic-y += bitsperlong.h

generic-y += bugs.h

generic-y += clkdev.h

generic-y += cputime.h

generic-y += device.h

generic-y += div64.h

generic-y += emergency-restart.h

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