linux-toradex.git/kernel/sched_fair.c, branch v2.6.31.1 Linux kernel for Apalis and Colibri modules sched: Fix latencytop and sleep profiling vs group scheduling 2009-08-02T12:10:12+00:00 Peter Zijlstra a.p.zijlstra@chello.nl 2009-07-23T18:13:26+00:00 e414314cce7539788dd5d2c35decad11782dd858 The latencytop and sleep accounting code assumes that any scheduler entity represents a task, this is not so. Cc: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu> 
The latencytop and sleep accounting code assumes that any
scheduler entity represents a task, this is not so.

Cc: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
sched: Account for vruntime wrapping 2009-07-18T09:17:08+00:00 Fabio Checconi fabio@gandalf.sssup.it 2009-07-16T10:32:27+00:00 54fdc5816631b43ba55fc3206d7add2d85850bc6 I spotted two sites that didn't take vruntime wrap-around into account. Fix these by creating a comparison helper that does do so. Signed-off-by: Fabio Checconi <fabio@gandalf.sssup.it> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu> 
I spotted two sites that didn't take vruntime wrap-around into
account. Fix these by creating a comparison helper that does do
so.

Signed-off-by: Fabio Checconi <fabio@gandalf.sssup.it>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
sched: Fix bug in SCHED_IDLE interaction with group scheduling 2009-07-11T08:00:09+00:00 Paul Turner pjt@google.com 2009-07-11T00:05:16+00:00 d07387b490b1c43bfcb9f3900faf96f2dafb2630 One of the isolation modifications for SCHED_IDLE is the unitization of sleeper credit. However the check for this assumes that the sched_entity we're placing always belongs to a task. This is potentially not true with group scheduling and leaves us rummaging randomly when we try to pull the policy. Signed-off-by: Paul Turner <pjt@google.com> Cc: peterz@infradead.org LKML-Reference: <alpine.DEB.1.00.0907101649570.29914@kitami.corp.google.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> 
One of the isolation modifications for SCHED_IDLE is the
unitization of sleeper credit.  However the check for this
assumes that the sched_entity we're placing always belongs to a
task.

This is potentially not true with group scheduling and leaves
us rummaging randomly when we try to pull the policy.

Signed-off-by: Paul Turner <pjt@google.com>
Cc: peterz@infradead.org
LKML-Reference: <alpine.DEB.1.00.0907101649570.29914@kitami.corp.google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
sched: Fix out of scope variable access in sched_slice() 2009-06-17T16:37:54+00:00 Christian Engelmayer christian.engelmayer@frequentis.com 2009-06-16T08:35:12+00:00 3104bf03a923c72043a9c5009d9cd56724304916 Access to local variable lw is aliased by usage of pointer load. Access to pointer load in calc_delta_mine() happens when lw is already out of scope. [ Reported by static code analysis. ] Signed-off-by: Christian Engelmayer <christian.engelmayer@frequentis.com> LKML-Reference: <20090616103512.0c846e51@frequentis.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> 
Access to local variable lw is aliased by usage of pointer load.
Access to pointer load in calc_delta_mine() happens when lw is
already out of scope.

[ Reported by static code analysis. ]

Signed-off-by: Christian Engelmayer <christian.engelmayer@frequentis.com>
LKML-Reference: <20090616103512.0c846e51@frequentis.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
sched: remove redundant hierarchy walk in check_preempt_wakeup 2009-04-09T06:19:08+00:00 Paul Turner pjt@google.com 2009-04-08T22:29:43+00:00 002f128b473fb82f454654be5081b0919ee01ab2 Impact: micro-optimization Under group scheduling we traverse up until we are at common siblings to make the wakeup comparison on. At this point however, they should have the same parent so continuing to check up the tree is redundant. Signed-off-by: Paul Turner <pjt@google.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <alpine.DEB.1.00.0904081520320.30317@kitami.corp.google.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> 
Impact: micro-optimization

Under group scheduling we traverse up until we are at common siblings
to make the wakeup comparison on.

At this point however, they should have the same parent so continuing
to check up the tree is redundant.

Signed-off-by: Paul Turner <pjt@google.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <alpine.DEB.1.00.0904081520320.30317@kitami.corp.google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Merge branch 'sched/urgent'; commit 'v2.6.29-rc5' into sched/core 2009-02-15T20:15:16+00:00 Ingo Molnar mingo@elte.hu 2009-02-15T20:15:16+00:00 5274f8354d6a1ed9d6688e6a89b705b94aa1b6e9 






sched: revert recent sync wakeup changes
2009-02-11T13:43:35+00:00

Peter Zijlstra
a.p.zijlstra@chello.nl

2009-02-11T13:27:17+00:00

fc631c82e1734d718ff0832558f64c8f5d185f26

Intel reported a 10% regression (mysql+sysbench) on a 16-way machine
with these patches:

  1596e29: sched: symmetric sync vs avg_overlap
  d942fb6: sched: fix sync wakeups

Revert them.

Reported-by: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
Bisected-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>





Intel reported a 10% regression (mysql+sysbench) on a 16-way machine
with these patches:

  1596e29: sched: symmetric sync vs avg_overlap
  d942fb6: sched: fix sync wakeups

Revert them.

Reported-by: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
Bisected-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>







Merge branches 'sched/rt' and 'sched/urgent' into sched/core
2009-02-08T19:12:46+00:00

Ingo Molnar
mingo@elte.hu

2009-02-08T19:12:46+00:00

140573d33b703194b7e1893711e78b7f546cca7c












sched: fix buddie group latency
2009-02-01T09:49:51+00:00

Peter Zijlstra
a.p.zijlstra@chello.nl

2009-01-28T13:51:40+00:00

a571bbeafbcc501d9989fbce1cddcd810bd51d71

Similar to the previous patch, by not clearing buddies we can select entities
past their run quota, which can increase latency. This means we have to clear
group buddies as well.

Do not use the group clear for pick_next_task(), otherwise that'll get O(n^2).

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>





Similar to the previous patch, by not clearing buddies we can select entities
past their run quota, which can increase latency. This means we have to clear
group buddies as well.

Do not use the group clear for pick_next_task(), otherwise that'll get O(n^2).

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>







sched: clear buddies more aggressively
2009-02-01T09:49:50+00:00

Mike Galbraith
efault@gmx.de

2009-01-28T13:51:39+00:00

a9f3e2b549f83a9cdab873abf4140be27c05a3f2

It was noticed that a task could get re-elected past its run quota due to buddy
affinities. This could increase latency a little. Cure it by more aggresively
clearing buddy state.

We do so in two situations:
 - when we force preempt
 - when we select a buddy to run

Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>





It was noticed that a task could get re-elected past its run quota due to buddy
affinities. This could increase latency a little. Cure it by more aggresively
clearing buddy state.

We do so in two situations:
 - when we force preempt
 - when we select a buddy to run

Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>