- When a new thread is added to a kseq the load is incremented prior to
adding it to the nice tables. Therefore, in kseq_add_nice, we should
keep in mind that the load will be 1 if we are the

- When a new thread is added to a kseq the load is incremented prior to
adding it to the nice tables. Therefore, in kseq_add_nice, we should
keep in mind that the load will be 1 if we are the only thread, and not
0.
- Assert that the sched lock is held in all the appropriate places.
- Increase the scope of the sched lock in sched_pctcpu_update().
- Hold the sched lock in sched_runnable(). It is not held by the caller.

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Fix typo in last commit

Move the flag that indicates an idle thread from the KSE to the thread.
It was always referenced via the thread anyhow.

Reviewed by: jhb (a LOOOOONG time ago)

Add lock assertions for various proc/thread/kse/ksegroup fields to the
scheduler functions.

- Assert that the proc lock and sched_lock are held in sched_nice().
- For the 4BSD scheduler, this means that all callers of the static
function resetpriority() now always hold sched_lock, so don'

- Assert that the proc lock and sched_lock are held in sched_nice().
- For the 4BSD scheduler, this means that all callers of the static
function resetpriority() now always hold sched_lock, so don't lock
sched_lock explicitly in that function.

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Protect p_swtime with the sched_lock.

- Set the ke_cpu field in sched_add() for interrupt and realtime threads
since they are going on the current cpu and not their previously assigned
cpu.
- sched_runnable() should only return tr

- Set the ke_cpu field in sched_add() for interrupt and realtime threads
since they are going on the current cpu and not their previously assigned
cpu.
- sched_runnable() should only return true in the SMP case if the other
processor has more than one thread that is runnable. We can not steal
curthread.
- Change kseq_print() to accept the cpuid instead of a kseq pointer. This
makes use of this function in ddb much easier.

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- Unbreak priority prop. for timeshare threads. Always place something on
the current queue if its priority is really elevated. This needs more work
as there are cases where a next queue kse

- Unbreak priority prop. for timeshare threads. Always place something on
the current queue if its priority is really elevated. This needs more work
as there are cases where a next queue kse could be holding up what would
be a curr queue kse, and thus hurting interactivity. Also, when a thread
with an elevated priority has its priority lowered it should be placed
back on the next queue.

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- Clean up some debug code left over from my earlier megacommit.

- We only care about the base priority. Ignore the SCHED_FIFO_BIT so that
we dont get confused.

Reported and debugged by: Steve Kargl <sgk@troutmask.apl.washington.edu>

- Add sched_exit_*
- Call sched_exit_kse() from sched_exit() instead of implementing it here.

- Only select kseqs with more than one kse to steal. The running kse
is reflected in the load now and you can't very well migrate that.

- When migrating a kse from one kseq to the next actually insert it onto
the second kseq's run queue so that it is referenced by the kse when
it is switched out.
- Spell ksq_rslices properly.

- When migrating a kse from one kseq to the next actually insert it onto
the second kseq's run queue so that it is referenced by the kse when
it is switched out.
- Spell ksq_rslices properly.

Reported by: Ian Freislich <ianf@za.uu.net>

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- Add a SYSCTL node for the ule scheduler.
- Allow user adjustable min and max time slices (suggested by hiten).
- Change the SLP_RUN_MAX to 100ms from 2 seconds so that we learn whether a
proce

- Add a SYSCTL node for the ule scheduler.
- Allow user adjustable min and max time slices (suggested by hiten).
- Change the SLP_RUN_MAX to 100ms from 2 seconds so that we learn whether a
process is interactive or not much more quickly.
- Place a process on the current run queue if it is interactive or if it is
running at an interrupt thread priority due to priority prop.
- Use the 'current' timeshare queue for interrupt threads, realtime threads,
and idle threads that are running at higher priority due to priority prop.
This fixes problems where priorities would have been elevated but we would
not check the timeshare run queue until other lower priority tasks were
no longer runnable.
- Keep an array of loads indexed by the priority class as well as a global
load.
- Keep an bucket of nice values with a count of the number of kses currently
runnable with that nice value.
- Keep track of the minimum nice value of any running thread.
- Remove the unused short term sleep accounting. I was attempting to use
this for load balancing but it didn't work out.
- Define a kseq_print() for use with debugging.
- Add KTR debugging at useful places so we can easily debug slice and
priority assignment.
- Decouple the runq assignment from the kseq assignment. kseq_add now keeps
track of statistics. This is done so that the nice and load is still
tracked for the currently running process. Previously if a niced process
was added while a non nice process was running the niced process would
still get a slice since it was not aware of the unnice process.
- Make adjustments for the sched api changes.

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Move the _oncpu entry from the KSE to the thread.
The entry in the KSE still exists but it's purpose will change a bit
when we add the ability to lock a KSE to a cpu.

- Keep seperate statistics and run queues for different scheduling classes.
- Treat each class specially in kseq_{choose,add,rem}. Let the rest of the
code be less aware of scheduling classes.

- Keep seperate statistics and run queues for different scheduling classes.
- Treat each class specially in kseq_{choose,add,rem}. Let the rest of the
code be less aware of scheduling classes.
- Skip the interactivity calculation for non TIMESHARE ksegrps.
- Move slice and runq selection into kseq_add(). Uninline it now that it's
big.

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- Make the interactivity calculator decay faster.
- Make the pcpu estimator update faster.

- I meant divide by two and not shift by two in SCHED_PRI_NHALF.

- Add in support for KSEs with 0 slice values on the run queue. If we try
to select a KSE with a slice of 0 we will update its slice and insert it
onto the next queue.
- Pass the KSE instead

- Add in support for KSEs with 0 slice values on the run queue. If we try
to select a KSE with a slice of 0 we will update its slice and insert it
onto the next queue.
- Pass the KSE instead of the ksegrp into sched_slice(). This more
accurately reflects the behavior of the code. Slices are granted to kses.
- Add a function kseq_nice_min() which finds the smallest nice value
assigned to the kseg of any KSE on the queue.
- Rewrite the logic in sched_slice(). Add a large comment describing the
new slice selection scheme. To summarize, slices are assigned based on
the nice value. Priorities are still calculated based on the nice and
interactivity of a process. Slice sizes of 0 may be granted for KSEs
whos nice is 20 or futher away from the lowest nice on the run queue.
Other nice values are scaled across the range [min, min+20]. This fixes
ULEs bad behavior with positively niced processes.

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- Create a function sched_interact_score() which decides on the
interactivity of a kseg and assigns it a value of 0 through 100.
- Use sched_interact_score() to determine the dynamic priority.
-

- Create a function sched_interact_score() which decides on the
interactivity of a kseg and assigns it a value of 0 through 100.
- Use sched_interact_score() to determine the dynamic priority.
- Define SCHED_CURR() in terms of sched_interact_score().
- Adjust the maximum slice back down to 100ms.
- Remove redundant clearing of ke_runq in sched_wakeup()
- Clean up #defines and comment them.

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- Shift the tick count by 10 and back around sched_pctcpu_update()
calculations. Keep this changes local to the function so the tick count
is in its natural form otherwise. Previously 1000 wa

- Shift the tick count by 10 and back around sched_pctcpu_update()
calculations. Keep this changes local to the function so the tick count
is in its natural form otherwise. Previously 1000 was added each time
a tick fired and we divided by 1000 when it was reported. This is done
to reduce rounding errors.

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- In sched_add() special case PRI_TIMESHARE and PRI_ITHD|PRI_REALTIME. We
always place ITHD & REALTIME threads on the current queue of the current
cpu. Prior to this change an interrupt threa

- In sched_add() special case PRI_TIMESHARE and PRI_ITHD|PRI_REALTIME. We
always place ITHD & REALTIME threads on the current queue of the current
cpu. Prior to this change an interrupt thread would only ever run on one
cpu.

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- Refrain from setting the td_priority in sched_wakeup(). It will be reset
before we return to user space.

Change the process flags P_KSES to be P_THREADED.
This is just a cosmetic change but I've been meaning to do it for about a year.

Move a bunch of flags from the KSE to the thread.
I was in two minds as to where to put them in the first case..
I should have listenned to the other mind.

Submitted by: parts by davidxu@
Reviewed

Move a bunch of flags from the KSE to the thread.
I was in two minds as to where to put them in the first case..
I should have listenned to the other mind.

Submitted by: parts by davidxu@
Reviewed by: jeff@ mini@

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