The latest sched-devel.git tree can be pulled from:
   git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched-devel.git
This is a quick iteration after yesterday's: a couple of group

scheduling bugs were found/debugged and fixed by Srivatsa Vaddagiri and

Mike Galbraith. There's also a yield fix from Dmitry Adamushko, a build

fix from S.Ceglar Onur and Andrew Morton, a cleanup from Hiroshi

Shimamoto and the usual stream of goodies from Peter Zijlstra. Rebased

it to -rc8 as well.
there are no known regressions at the moment in the sched-devel.git

codebase. (yay :)
	Ingo
----------------------------------------->

the shortlog relative to 2.6.23-rc8:
Dmitry Adamushko (9):

      sched: clean up struct load_stat

      sched: clean up schedstat block in dequeue_entity()

      sched: sched_setscheduler() fix

      sched: add set_curr_task() calls

      sched: do not keep current in the tree and get rid of sched_entity::fair_key

      sched: optimize task_new_fair()

      sched: simplify sched_class::yield_task()

      sched: rework enqueue/dequeue_entity() to get rid of set_curr_task()

      sched: yield fix
Hiroshi Shimamoto (1):

      sched: clean up sched_fork()
Ingo Molnar (44):

      sched: fix new-task method

      sched: resched task in task_new_fair()

      sched: small sched_debug cleanup

      sched: debug: track maximum 'slice'

      sched: uniform tunings

      sched: use constants if !CONFIG_SCHED_DEBUG

      sched: remove stat_gran

      sched: remove precise CPU load

      sched: remove precise CPU load calculations #2

      sched: track cfs_rq->curr on !group-scheduling too

      sched: cleanup: simplify cfs_rq_curr() methods

      sched: uninline __enqueue_entity()/__dequeue_entity()

      sched: speed up update_load_add/_sub()

      sched: clean up calc_weighted()

      sched: introduce se->vruntime

      sched: move sched_feat() definitions

      sched: optimize vruntime based scheduling

      sched: simplify c...
[ message continues ]

Ingo,

	Few more patches follow on top of this latest sched-devel tree.
Pls consider for inclusion.
--

Regards,

vatsa

-

thanks, applied.
	Ingo

-

There is a possibility that because of task of a group moving from one

cpu to another, it may gain more cpu time that desired. See

http://marc.info/?l=linux-kernel&m=119073197730334 for details.
This is an attempt to fix that problem. Basically it simulates dequeue

of higher level entities as if they are going to sleep. Similarly it

simulate wakeup of higher level entities as if they are waking up from

sleep.
Signed-off-by : Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
---

 kernel/sched_fair.c |    2 ++

 1 files changed, 2 insertions(+)
Index: current/kernel/sched_fair.c

===================================================================

--- current.orig/kernel/sched_fair.c

+++ current/kernel/sched_fair.c

@@ -715,6 +715,7 @@ static void enqueue_task_fair(struct rq

 			break;

 		cfs_rq = cfs_rq_of(se);

 		enqueue_entity(cfs_rq, se, wakeup);

+		wakeup = 1;

 	}

 }
@@ -734,6 +735,7 @@ static void dequeue_task_fair(struct rq

 		/* Don't dequeue parent if it has other entities besides us */

 		if (cfs_rq->load.weight)

 			break;

+		sleep = 1;

 	}

 }
--

Regards,

vatsa

-

Recent fix to check_preempt_wakeup() to check for preemption at higher

levels caused a size bloat for !CONFIG_FAIR_GROUP_SCHED.
Fix the problem.
  42277   10598     320   53195    cfcb kernel/sched.o-before_this_patch

  42216   10598     320   53134    cf8e kernel/sched.o-after_this_patch
Signed-off-by : Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
---

 kernel/sched_fair.c |   43 +++++++++++++++++++++++++------------------

 1 files changed, 25 insertions(+), 18 deletions(-)
Index: current/kernel/sched_fair.c

===================================================================

--- current.orig/kernel/sched_fair.c

+++ current/kernel/sched_fair.c

@@ -640,15 +640,21 @@ static inline struct cfs_rq *cpu_cfs_rq(

 #define for_each_leaf_cfs_rq(rq, cfs_rq) \

 	list_for_each_entry(cfs_rq, &rq->leaf_cfs_rq_list, leaf_cfs_rq_list)
-/* Do the two (enqueued) tasks belong to the same group ? */

-static inline int is_same_group(struct task_struct *curr, struct task_struct *p)

+/* Do the two (enqueued) entities belong to the same group ? */

+static inline int

+is_same_group(struct sched_entity *se, struct sched_entity *pse)

 {

-	if (curr->se.cfs_rq == p->se.cfs_rq)

+	if (se->cfs_rq == pse->cfs_rq)

 		return 1;
 	return 0;

 }
+static inline struct sched_entity *parent_entity(struct sched_entity *se)

+{

+	return se->parent;

+}

+

 #else	/* CONFIG_FAIR_GROUP_SCHED */
 #define for_each_sched_entity(se) \

@@ -681,11 +687,17 @@ static inline struct cfs_rq *cpu_cfs_rq(

 #define for_each_leaf_cfs_rq(rq, cfs_rq) \

 		for (cfs_rq = &rq->cfs; cfs_rq; cfs_rq = NULL)
-static inline int is_same_group(struct task_struct *curr, struct task_struct *p)

+static inline int

+is_same_group(struct sched_entity *se, struct sched_entity *pse)

 {

 	return 1;

 }
+static inline struct sched_entity *parent_entity(struct sched_entity *se)

+{

+	return NULL;

+}

+

 #endif	/* CONFIG_FAIR_GROUP_SCHED */
 /*

@@ -775,8 +787,9 @@ static void yield_tas...
[ message continues ]

Fix coding style issues reported by Randy Dunlap and others
Signed-off-by : Dhaval Giani <dhaval@linux.vnet.ibm.com>

Signed-off-by : Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
---

 init/Kconfig         |   14 +++++++-------

 kernel/sched_debug.c |    8 ++------

 2 files changed, 9 insertions(+), 13 deletions(-)
Index: current/init/Kconfig

===================================================================

--- current.orig/init/Kconfig

+++ current/init/Kconfig

@@ -282,11 +282,11 @@ config CPUSETS

 	  Say N if unsure.
 config FAIR_GROUP_SCHED

-	bool "Fair group cpu scheduler"

+	bool "Fair group CPU scheduler"

 	default y

 	depends on EXPERIMENTAL

 	help

-	  This feature lets cpu scheduler recognize task groups and control cpu

+	  This feature lets CPU scheduler recognize task groups and control CPU

 	  bandwidth allocation to such task groups.
 choice

@@ -294,11 +294,11 @@ choice

 	prompt "Basis for grouping tasks"

 	default FAIR_USER_SCHED
-	config FAIR_USER_SCHED

-		bool "user id"

-		help

-		  This option will choose userid as the basis for grouping

-		  tasks, thus providing equal cpu bandwidth to each user.

+config FAIR_USER_SCHED

+	bool "user id"

+	help

+	  This option will choose userid as the basis for grouping

+	  tasks, thus providing equal CPU bandwidth to each user.
 endchoice
Index: current/kernel/sched_debug.c

===================================================================

--- current.orig/kernel/sched_debug.c

+++ current/kernel/sched_debug.c

@@ -239,11 +239,7 @@ static int

 root_user_share_read_proc(char *page, char **start, off_t off, int count,

 				 int *eof, void *data)

 {

-	int len;

-

-	len = sprintf(page, "%d\n", init_task_grp_load);

-

-	return len;

+	return sprintf(page, "%d\n", init_task_grp_load);

 }
 static int

@@ -297,7 +293,7 @@ static int __init init_sched_debug_procf

 	pe->proc_fops = &sched_debug_fops;
 #ifdef CONFIG_FAIR_USER_SCHED

-	pe = create_proc_entry("root_user_share", 064...
[ message continues ]

What about moving this debug stuff under debugfs?

Please consider using the functions in <linux/debugfs.h> .

They compile into nothing, if DEBUGFS is not compiled in

and have already useful functions for reading/writing integers

and booleans.
Best Regards
Ingo Oeser

-

Hi Ingo,
This is not debug stuff. It is a tunable to give the root user more

weight with respect to the other users.
--

regards,

Dhaval

-

Umm, that's not a debugging thing.  It appears to be a tunable

allowing you to configure what percentage of the total CPU that UID 0

gets which is likely to be useful to configure on production systems;

at least until better group-scheduling tools are produced.
Cheers,

Kyle Moffett
-

This is required for it to compile.
---

 include/linux/sched.h |    1 +

 1 files changed, 1 insertion(+)
Index: current/include/linux/sched.h

===================================================================

--- current.orig/include/linux/sched.h

+++ current/include/linux/sched.h

@@ -1404,6 +1404,7 @@ extern unsigned int sysctl_sched_wakeup_

 extern unsigned int sysctl_sched_batch_wakeup_granularity;

 extern unsigned int sysctl_sched_child_runs_first;

 extern unsigned int sysctl_sched_features;

+extern unsigned int sysctl_sched_nr_latency;

 #endif
 extern unsigned int sysctl_sched_compat_yield;
--

Regards,

vatsa

-

and this:
---

 kernel/sched_debug.c |    1 -

 1 files changed, 1 deletion(-)
Index: current/kernel/sched_debug.c

===================================================================

--- current.orig/kernel/sched_debug.c

+++ current/kernel/sched_debug.c

@@ -210,7 +210,6 @@ static int sched_debug_show(struct seq_f

 #define PN(x) \

 	SEQ_printf(m, "  .%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))

 	PN(sysctl_sched_latency);

-	PN(sysctl_sched_min_granularity);

 	PN(sysctl_sched_wakeup_granularity);

 	PN(sysctl_sched_batch_wakeup_granularity);

 	PN(sysctl_sched_child_runs_first);
--

Regards,

vatsa

-