__sched_setscheduler() goes through an enqueue/dequeue cycle like so:
flags := DEQUEUE_SAVE | DEQUEUE_MOVE | DEQUEUE_NOCLOCK;
prev_class->dequeue_task(rq, p, flags);
new_class->enqueue_task(rq, p, flags);
when prev_class := fair_sched_class, this is followed by:
dequeue_task(rq, p, DEQUEUE_NOCLOCK | DEQUEUE_SLEEP);
the idea being that since the task has switched classes, we need to drop
the sched_delayed logic and have that task be deactivated per its previous
dequeue_task(..., DEQUEUE_SLEEP).
Unfortunately, this leaves the task on_rq. This is missing the tail end of
dequeue_entities() that issues __block_task(), which __sched_setscheduler()
won't have done due to not using DEQUEUE_DELAYED - not that it should, as
it is pretty much a fair_sched_class specific thing.
Make switched_from_fair() properly deactivate sched_delayed tasks upon
class changes via __block_task(), as if a
dequeue_task(..., DEQUEUE_DELAYED)
had been issued.
Fixes: 2e0199df25 ("sched/fair: Prepare exit/cleanup paths for delayed_dequeue")
Reported-by: "Paul E. McKenney" <paulmck@kernel.org>
Reported-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Valentin Schneider <vschneid@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20240829135353.1524260-1-vschneid@redhat.com
In dl_server_start(), when schedstats is enabled, the following
happens:
dl_server_start()
dl_se->dl_server = 1;
enqueue_dl_entity()
update_stats_enqueue_dl()
__schedstats_from_dl_se()
dl_task_of()
BUG_ON(dl_server(dl_se));
Since only tasks have schedstats and internal entries do not, avoid
trying to update stats in this case.
Fixes: 63ba8422f8 ("sched/deadline: Introduce deadline servers")
Signed-off-by: Huang Shijie <shijie@os.amperecomputing.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20240829031111.12142-1-shijie@os.amperecomputing.com
In the absence of an explicit cgroup slice configureation, make mixed
slice length work with cgroups by propagating the min_slice up the
hierarchy.
This ensures the cgroup entity gets timely service to service its
entities that have this timing constraint set on them.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105030.948188417@infradead.org
Allow applications to directly set a suggested request/slice length using
sched_attr::sched_runtime.
The implementation clamps the value to: 0.1[ms] <= slice <= 100[ms]
which is 1/10 the size of HZ=1000 and 10 times the size of HZ=100.
Applications should strive to use their periodic runtime at a high
confidence interval (95%+) as the target slice. Using a smaller slice
will introduce undue preemptions, while using a larger value will
increase latency.
For all the following examples assume a scheduling quantum of 8, and for
consistency all examples have W=4:
{A,B,C,D}(w=1,r=8):
ABCD...
+---+---+---+---
t=0, V=1.5 t=1, V=3.5
A |------< A |------<
B |------< B |------<
C |------< C |------<
D |------< D |------<
---+*------+-------+--- ---+--*----+-------+---
t=2, V=5.5 t=3, V=7.5
A |------< A |------<
B |------< B |------<
C |------< C |------<
D |------< D |------<
---+----*--+-------+--- ---+------*+-------+---
Note: 4 identical tasks in FIFO order
~~~
{A,B}(w=1,r=16) C(w=2,r=16)
AACCBBCC...
+---+---+---+---
t=0, V=1.25 t=2, V=5.25
A |--------------< A |--------------<
B |--------------< B |--------------<
C |------< C |------<
---+*------+-------+--- ---+----*--+-------+---
t=4, V=8.25 t=6, V=12.25
A |--------------< A |--------------<
B |--------------< B |--------------<
C |------< C |------<
---+-------*-------+--- ---+-------+---*---+---
Note: 1 heavy task -- because q=8, double r such that the deadline of the w=2
task doesn't go below q.
Note: observe the full schedule becomes: W*max(r_i/w_i) = 4*2q = 8q in length.
Note: the period of the heavy task is half the full period at:
W*(r_i/w_i) = 4*(2q/2) = 4q
~~~
{A,C,D}(w=1,r=16) B(w=1,r=8):
BAACCBDD...
+---+---+---+---
t=0, V=1.5 t=1, V=3.5
A |--------------< A |---------------<
B |------< B |------<
C |--------------< C |--------------<
D |--------------< D |--------------<
---+*------+-------+--- ---+--*----+-------+---
t=3, V=7.5 t=5, V=11.5
A |---------------< A |---------------<
B |------< B |------<
C |--------------< C |--------------<
D |--------------< D |--------------<
---+------*+-------+--- ---+-------+--*----+---
t=6, V=13.5
A |---------------<
B |------<
C |--------------<
D |--------------<
---+-------+----*--+---
Note: 1 short task -- again double r so that the deadline of the short task
won't be below q. Made B short because its not the leftmost task, but is
eligible with the 0,1,2,3 spread.
Note: like with the heavy task, the period of the short task observes:
W*(r_i/w_i) = 4*(1q/1) = 4q
~~~
A(w=1,r=16) B(w=1,r=8) C(w=2,r=16)
BCCAABCC...
+---+---+---+---
t=0, V=1.25 t=1, V=3.25
A |--------------< A |--------------<
B |------< B |------<
C |------< C |------<
---+*------+-------+--- ---+--*----+-------+---
t=3, V=7.25 t=5, V=11.25
A |--------------< A |--------------<
B |------< B |------<
C |------< C |------<
---+------*+-------+--- ---+-------+--*----+---
t=6, V=13.25
A |--------------<
B |------<
C |------<
---+-------+----*--+---
Note: 1 heavy and 1 short task -- combine them all.
Note: both the short and heavy task end up with a period of 4q
~~~
A(w=1,r=16) B(w=2,r=16) C(w=1,r=8)
BBCAABBC...
+---+---+---+---
t=0, V=1 t=2, V=5
A |--------------< A |--------------<
B |------< B |------<
C |------< C |------<
---+*------+-------+--- ---+----*--+-------+---
t=3, V=7 t=5, V=11
A |--------------< A |--------------<
B |------< B |------<
C |------< C |------<
---+------*+-------+--- ---+-------+--*----+---
t=7, V=15
A |--------------<
B |------<
C |------<
---+-------+------*+---
Note: as before but permuted
~~~
From all this it can be deduced that, for the steady state:
- the total period (P) of a schedule is: W*max(r_i/w_i)
- the average period of a task is: W*(r_i/w_i)
- each task obtains the fair share: w_i/W of each full period P
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105030.842834421@infradead.org
Part of the reason to have shorter slices is to improve
responsiveness. Allow shorter slices to preempt longer slices on
wakeup.
Task | Runtime ms | Switches | Avg delay ms | Max delay ms | Sum delay ms |
100ms massive_intr 500us cyclictest NO_PREEMPT_SHORT
1 massive_intr:(5) | 846018.956 ms | 779188 | avg: 0.273 ms | max: 58.337 ms | sum:212545.245 ms |
2 massive_intr:(5) | 853450.693 ms | 792269 | avg: 0.275 ms | max: 71.193 ms | sum:218263.588 ms |
3 massive_intr:(5) | 843888.920 ms | 771456 | avg: 0.277 ms | max: 92.405 ms | sum:213353.221 ms |
1 chromium-browse:(8) | 53015.889 ms | 131766 | avg: 0.463 ms | max: 36.341 ms | sum:60959.230 ms |
2 chromium-browse:(8) | 53864.088 ms | 136962 | avg: 0.480 ms | max: 27.091 ms | sum:65687.681 ms |
3 chromium-browse:(9) | 53637.904 ms | 132637 | avg: 0.481 ms | max: 24.756 ms | sum:63781.673 ms |
1 cyclictest:(5) | 12615.604 ms | 639689 | avg: 0.471 ms | max: 32.272 ms | sum:301351.094 ms |
2 cyclictest:(5) | 12511.583 ms | 642578 | avg: 0.448 ms | max: 44.243 ms | sum:287632.830 ms |
3 cyclictest:(5) | 12545.867 ms | 635953 | avg: 0.475 ms | max: 25.530 ms | sum:302374.658 ms |
100ms massive_intr 500us cyclictest PREEMPT_SHORT
1 massive_intr:(5) | 839843.919 ms | 837384 | avg: 0.264 ms | max: 74.366 ms | sum:221476.885 ms |
2 massive_intr:(5) | 852449.913 ms | 845086 | avg: 0.252 ms | max: 68.162 ms | sum:212595.968 ms |
3 massive_intr:(5) | 839180.725 ms | 836883 | avg: 0.266 ms | max: 69.742 ms | sum:222812.038 ms |
1 chromium-browse:(11) | 54591.481 ms | 138388 | avg: 0.458 ms | max: 35.427 ms | sum:63401.508 ms |
2 chromium-browse:(8) | 52034.541 ms | 132276 | avg: 0.436 ms | max: 31.826 ms | sum:57732.958 ms |
3 chromium-browse:(8) | 55231.771 ms | 141892 | avg: 0.469 ms | max: 27.607 ms | sum:66538.697 ms |
1 cyclictest:(5) | 13156.391 ms | 667412 | avg: 0.373 ms | max: 38.247 ms | sum:249174.502 ms |
2 cyclictest:(5) | 12688.939 ms | 665144 | avg: 0.374 ms | max: 33.548 ms | sum:248509.392 ms |
3 cyclictest:(5) | 13475.623 ms | 669110 | avg: 0.370 ms | max: 37.819 ms | sum:247673.390 ms |
As per the numbers the, this makes cyclictest (short slice) it's
max-delay more consistent and consistency drops the sum-delay. The
trade-off is that the massive_intr (long slice) gets more context
switches and a slight increase in sum-delay.
Chunxin contributed did_preempt_short() where a task that lost slice
protection from PREEMPT_SHORT gets rescheduled once it becomes
in-eligible.
[mike: numbers]
Co-Developed-by: Chunxin Zang <zangchunxin@lixiang.com>
Signed-off-by: Chunxin Zang <zangchunxin@lixiang.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Tested-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Link: https://lkml.kernel.org/r/20240727105030.735459544@infradead.org
During OSPM24 Youssef noted that migrations are re-setting the virtual
deadline. Notably everything that does a dequeue-enqueue, like setting
nice, changing preferred numa-node, and a myriad of other random crap,
will cause this to happen.
This shouldn't be. Preserve the relative virtual deadline across such
dequeue/enqueue cycles.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105030.625119246@infradead.org
Note that tasks that are kept on the runqueue to burn off negative
lag, are not in fact runnable anymore, they'll get dequeued the moment
they get picked.
As such, don't count this time towards runnable.
Thanks to Valentin for spotting I had this backwards initially.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105030.514088302@infradead.org
'Extend' DELAY_DEQUEUE by noting that since we wanted to dequeued them
at the 0-lag point, truncate lag (eg. don't let them earn positive
lag).
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105030.403750550@infradead.org
Extend / fix 86bfbb7ce4 ("sched/fair: Add lag based placement") by
noting that lag is fundamentally a temporal measure. It should not be
carried around indefinitely.
OTOH it should also not be instantly discarded, doing so will allow a
task to game the system by purposefully (micro) sleeping at the end of
its time quantum.
Since lag is intimately tied to the virtual time base, a wall-time
based decay is also insufficient, notably competition is required for
any of this to make sense.
Instead, delay the dequeue and keep the 'tasks' on the runqueue,
competing until they are eligible.
Strictly speaking, we only care about keeping them until the 0-lag
point, but that is a difficult proposition, instead carry them around
until they get picked again, and dequeue them at that point.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105030.226163742@infradead.org
Since special task states must not suffer spurious wakeups, and the
proposed delayed dequeue can cause exactly these (under some boundary
conditions), propagate this knowledge into dequeue_task() such that it
can do the right thing.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105030.110439521@infradead.org
The special task states are those that do not suffer spurious wakeups,
TASK_FROZEN is very much one of those, mark it as such.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105029.998329901@infradead.org
Doing a wakeup on a delayed dequeue task is about as simple as it
sounds -- remove the delayed mark and enjoy the fact it was actually
still on the runqueue.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105029.888107381@infradead.org
Delayed dequeue's natural end is when it gets picked again. Ensure
pick_next_task() knows what to do with delayed tasks.
Note, this relies on the earlier patch that made pick_next_task()
state invariant -- it will restart the pick on dequeue, because
obviously the just dequeued task is no longer eligible.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105029.747330118@infradead.org
When dequeue_task() is delayed it becomes possible to exit a task (or
cgroup) that is still enqueued. Ensure things are dequeued before
freeing.
Thanks to Valentin for asking the obvious questions and making
switched_from_fair() less weird.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105029.631948434@infradead.org
Just a little sanity test..
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105029.486423066@infradead.org
Delayed dequeue has tasks sit around on the runqueue that are not
actually runnable -- specifically, they will be dequeued the moment
they get picked.
One side-effect is that such a task can get migrated, which leads to a
'nested' dequeue_task() scenario that messes up uclamp if we don't
take care.
Notably, dequeue_task(DEQUEUE_SLEEP) can 'fail' and keep the task on
the runqueue. This however will have removed the task from uclamp --
per uclamp_rq_dec() in dequeue_task(). So far so good.
However, if at that point the task gets migrated -- or nice adjusted
or any of a myriad of operations that does a dequeue-enqueue cycle --
we'll pass through dequeue_task()/enqueue_task() again. Without
modification this will lead to a double decrement for uclamp, which is
wrong.
Reported-by: Luis Machado <luis.machado@arm.com>
Reported-by: Hongyan Xia <hongyan.xia2@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105029.315205425@infradead.org
While most of the delayed dequeue code can be done inside the
sched_class itself, there is one location where we do not have an
appropriate hook, namely ttwu_runnable().
Add an ENQUEUE_DELAYED call to the on_rq path to deal with waking
delayed dequeue tasks.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105029.200000445@infradead.org
As a preparation for dequeue_task() failing, and a second code-path
needing to take care of the 'success' path, split out the DEQEUE_SLEEP
path from deactivate_task().
Much thanks to Libo for spotting and fixing a TASK_ON_RQ_MIGRATING
ordering fail.
Fixed-by: Libo Chen <libo.chen@oracle.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105029.086192709@infradead.org
Working towards delaying dequeue, notably also inside the hierachy,
rework dequeue_task_fair() such that it can 'resume' an interrupted
hierarchy walk.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105028.977256873@infradead.org
Change the function signature of sched_class::dequeue_task() to return
a boolean, allowing future patches to 'fail' dequeue.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105028.864630153@infradead.org
Implement pick_next_task_fair() in terms of pick_task_fair() to
de-duplicate the pick loop.
More importantly, this makes all the pick loops use the
state-invariant form, which is useful to introduce further re-try
conditions in later patches.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105028.725062368@infradead.org
With 4c456c9ad3 ("sched/fair: Remove unused 'curr' argument from
pick_next_entity()") curr is no longer being used, so no point in
clearing it.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105028.614707623@infradead.org
Per 54d27365ca ("sched/fair: Prevent throttling in early
pick_next_task_fair()") the reason check_cfs_rq_runtime() is under the
'if (curr)' check is to ensure the (downward) traversal does not
result in an empty cfs_rq.
But then the pick_task_fair() 'copy' of all this made it restart the
traversal anyway, so that seems to solve the issue too.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Ben Segall <bsegall@google.com>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105028.501679876@infradead.org
Since commit e8f331bcc2 ("sched/smp: Use lag to simplify
cross-runqueue placement") the min_vruntime_copy is no longer used.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Tested-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lkml.kernel.org/r/20240727105028.395297941@infradead.org
Some find the name realtime overloaded. Use rt_or_dl() as an
alternative, hopefully better, name.
Suggested-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Signed-off-by: Qais Yousef <qyousef@layalina.io>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240610192018.1567075-4-qyousef@layalina.io
rt_task() checks if a task has RT priority. But depends on your
dictionary, this could mean it belongs to RT class, or is a 'realtime'
task, which includes RT and DL classes.
Since this has caused some confusion already on discussion [1], it
seemed a clean up is due.
I define the usage of rt_task() to be tasks that belong to RT class.
Make sure that it returns true only for RT class and audit the users and
replace the ones required the old behavior with the new realtime_task()
which returns true for RT and DL classes. Introduce similar
realtime_prio() to create similar distinction to rt_prio() and update
the users that required the old behavior to use the new function.
Move MAX_DL_PRIO to prio.h so it can be used in the new definitions.
Document the functions to make it more obvious what is the difference
between them. PI-boosted tasks is a factor that must be taken into
account when choosing which function to use.
Rename task_is_realtime() to realtime_task_policy() as the old name is
confusing against the new realtime_task().
No functional changes were intended.
[1] https://lore.kernel.org/lkml/20240506100509.GL40213@noisy.programming.kicks-ass.net/
Signed-off-by: Qais Yousef <qyousef@layalina.io>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Phil Auld <pauld@redhat.com>
Reviewed-by: "Steven Rostedt (Google)" <rostedt@goodmis.org>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lore.kernel.org/r/20240610192018.1567075-2-qyousef@layalina.io
This code has an integer overflow or sign extension bug which was caught
by gcc-13:
kernel/sched/debug.c:341:57: error: integer overflow in expression of
type 'long int' results in '-100663296' [-Werror=overflow]
341 | static unsigned long fair_server_period_max = (1 << 22) * NSEC_PER_USEC; /* ~4 seconds */
The result is that "fair_server_period_max" is set to 0xfffffffffa000000
(585 years) instead of instead of 0xfa000000 (4 seconds) that was
intended.
Fix this by changing the type to shift from (1 << 22) to (1UL << 22).
Closes: https://lore.kernel.org/all/CA+G9fYtE2GAbeqU+AOCffgo2oH0RTJUxU+=Pi3cFn4di_KgBAQ@mail.gmail.com/
Fixes: d741f297bc ("sched/fair: Fair server interface")
Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
Reported-by: Arnd Bergmann <arnd@kernel.org>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/a936b991-e464-4bdf-94ab-08e25d364986@stanley.mountain
balance_fair() skips newidle balancing if rq->nr_running - there are already
tasks on the rq, so no need to try to pull tasks. This tests the total
number of queued tasks on the CPU instead of only the fair class, but is
still correct as the rq can currently only have fair class tasks while
balance_fair() is running.
However, with the addition of sched_ext below the fair class, this will not
hold anymore and make put_prev_task_balance() skip sched_ext's balance()
incorrectly as, when a CPU has only lower priority class tasks,
rq->nr_running would still be positive and balance_fair() would return 1
even when fair doesn't have any tasks to run.
Update balance_fair() to use sched_fair_runnable() which tests
rq->cfs.nr_running which is updated by bandwidth throttling. Note that
pick_next_task_fair() already uses sched_fair_runnable() in its optimized
path for the same purpose.
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev>
Reviewed-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/ZrFUjlCf7x3TNXB8@slm.duckdns.org
The throttle interaction made my brain hurt, make it consistently
about 0 transitions of h_nr_running.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Now that fair_server exists, we no longer need RT bandwidth control
unless RT_GROUP_SCHED.
Enable fair_server with parameters equivalent to RT throttling.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: "Vineeth Pillai (Google)" <vineeth@bitbyteword.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lore.kernel.org/r/14d562db55df5c3c780d91940743acb166895ef7.1716811044.git.bristot@kernel.org
* Use simple CFS pick_task for DL pick_task
DL server's pick_task calls CFS's pick_next_task_fair(), this is wrong
because core scheduling's pick_task only calls CFS's pick_task() for
evaluation / checking of the CFS task (comparing across CPUs), not for
actually affirmatively picking the next task. This causes RB tree
corruption issues in CFS that were found by syzbot.
* Make pick_task_fair clear DL server
A DL task pick might set ->dl_server, but it is possible the task will
never run (say the other HT has a stop task). If the CFS task is picked
in the future directly (say without DL server), ->dl_server will be
set. So clear it in pick_task_fair().
This fixes the KASAN issue reported by syzbot in set_next_entity().
(DL refactoring suggestions by Vineeth Pillai).
Reported-by: Suleiman Souhlal <suleiman@google.com>
Signed-off-by: "Joel Fernandes (Google)" <joel@joelfernandes.org>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vineeth Pillai <vineeth@bitbyteword.org>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lore.kernel.org/r/b10489ab1f03d23e08e6097acea47442e7d6466f.1716811044.git.bristot@kernel.org
In core scheduling, a DL server pick (which is CFS task) should be
given higher priority than tasks in other classes.
Not doing so causes CFS starvation. A kselftest is added later to
demonstrate this. A CFS task that is competing with RT tasks can
be completely starved without this and the DL server's boosting
completely ignored.
Fix these problems.
Reported-by: Suleiman Souhlal <suleiman@google.com>
Signed-off-by: "Joel Fernandes (Google)" <joel@joelfernandes.org>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vineeth Pillai <vineeth@bitbyteword.org>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lore.kernel.org/r/48b78521d86f3b33c24994d843c1aad6b987dda9.1716811044.git.bristot@kernel.org
Add an interface for fair server setup on debugfs.
Each CPU has two files under /debug/sched/fair_server/cpu{ID}:
- runtime: set runtime in ns
- period: set period in ns
This then leaves /proc/sys/kernel/sched_rt_{period,runtime}_us to set
bounds on admission control.
The interface also add the server to the dl bandwidth accounting.
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lore.kernel.org/r/a9ef9fc69bcedb44bddc9bc34f2b313296052819.1716811044.git.bristot@kernel.org
Among the motivations for the DL servers is the real-time throttling
mechanism. This mechanism works by throttling the rt_rq after
running for a long period without leaving space for fair tasks.
The base dl server avoids this problem by boosting fair tasks instead
of throttling the rt_rq. The point is that it boosts without waiting
for potential starvation, causing some non-intuitive cases.
For example, an IRQ dispatches two tasks on an idle system, a fair
and an RT. The DL server will be activated, running the fair task
before the RT one. This problem can be avoided by deferring the
dl server activation.
By setting the defer option, the dl_server will dispatch an
SCHED_DEADLINE reservation with replenished runtime, but throttled.
The dl_timer will be set for the defer time at (period - runtime) ns
from start time. Thus boosting the fair rq at defer time.
If the fair scheduler has the opportunity to run while waiting
for defer time, the dl server runtime will be consumed. If
the runtime is completely consumed before the defer time, the
server will be replenished while still in a throttled state. Then,
the dl_timer will be reset to the new defer time
If the fair server reaches the defer time without consuming
its runtime, the server will start running, following CBS rules
(thus without breaking SCHED_DEADLINE). Then the server will
continue the running state (without deferring) until it fair
tasks are able to execute as regular fair scheduler (end of
the starvation).
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lore.kernel.org/r/dd175943c72533cd9f0b87767c6499204879cc38.1716811044.git.bristot@kernel.org
Use deadline servers to service fair tasks.
This patch adds a fair_server deadline entity which acts as a container
for fair entities and can be used to fix starvation when higher priority
(wrt fair) tasks are monopolizing CPU(s).
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lore.kernel.org/r/b6b0bcefaf25391bcf5b6ecdb9f1218de402d42e.1716811044.git.bristot@kernel.org
In case the previous pick was a DL server pick, ->dl_server might be
set. Clear it in the fast path as well.
Fixes: 63ba8422f8 ("sched/deadline: Introduce deadline servers")
Signed-off-by: Youssef Esmat <youssefesmat@google.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/7f7381ccba09efcb4a1c1ff808ed58385eccc222.1716811044.git.bristot@kernel.org
Paths using put_prev_task_balance() need to do a pick shortly
after. Make sure they also clear the ->dl_server on prev as a
part of that.
Fixes: 63ba8422f8 ("sched/deadline: Introduce deadline servers")
Signed-off-by: "Joel Fernandes (Google)" <joel@joelfernandes.org>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/d184d554434bedbad0581cb34656582d78655150.1716811044.git.bristot@kernel.org
Consider the following cgroup:
root
|
------------------------
| |
normal_cgroup idle_cgroup
| |
SCHED_IDLE task_A SCHED_NORMAL task_B
According to the cgroup hierarchy, A should preempt B. But current
check_preempt_wakeup_fair() treats cgroup se and task separately, so B
will preempt A unexpectedly.
Unify the wakeup logic by {c,p}se_is_idle only. This makes SCHED_IDLE of
a task a relative policy that is effective only within its own cgroup,
similar to the behavior of NICE.
Also fix se_is_idle() definition when !CONFIG_FAIR_GROUP_SCHED.
Fixes: 304000390f ("sched: Cgroup SCHED_IDLE support")
Signed-off-by: Tianchen Ding <dtcccc@linux.alibaba.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Josh Don <joshdon@google.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/20240626023505.1332596-1-dtcccc@linux.alibaba.com
As a hedge against unexpected user issues commit 88c56cfeae
("sched/fair: Block nohz tick_stop when cfs bandwidth in use")
included a scheduler feature to disable the new functionality.
It's been a few releases (v6.6) and no screams, so remove it.
Signed-off-by: Phil Auld <pauld@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <vschneid@redhat.com>
Link: https://lore.kernel.org/r/20240515133705.3632915-1-pauld@redhat.com
nr_spread_over tracks the number of instances where the difference
between a scheduling entity's virtual runtime and the minimum virtual
runtime in the runqueue exceeds three times the scheduler latency,
indicating significant disparity in task scheduling.
Commit that removed its usage: 5e963f2bd: sched/fair: Commit to EEVDF
cfs_rq->exec_clock was used to account for time spent executing tasks.
Commit that removed its usage: 5d69eca542 sched: Unify runtime
accounting across classes
cfs_rq::nr_spread_over and cfs_rq::exec_clock are not used anymore in
eevdf. Remove them from struct cfs_rq.
Signed-off-by: Chuyi Zhou <zhouchuyi@bytedance.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev>
Reviewed-by: K Prateek Nayak <kprateek.nayak@amd.com>
Acked-by: Vishal Chourasia <vishalc@linux.ibm.com>
Link: https://lore.kernel.org/r/20240717143342.593262-1-zhouchuyi@bytedance.com
Background
==========
When repeated migrate_disable() calls are made with missing the
corresponding migrate_enable() calls, there is a risk of
'migration_disabled' going upper overflow because
'migration_disabled' is a type of unsigned short whose max value is
65535.
In PREEMPT_RT kernel, if 'migration_disabled' goes upper overflow, it may
make the migrate_disable() ineffective within local_lock_irqsave(). This
is because, during the scheduling procedure, the value of
'migration_disabled' will be checked, which can trigger CPU migration.
Consequently, the count of 'rcu_read_lock_nesting' may leak due to
local_lock_irqsave() and local_unlock_irqrestore() occurring on different
CPUs.
Usecase
========
For example, When I developed a driver, I encountered a warning like
"WARNING: CPU: 4 PID: 260 at kernel/rcu/tree_plugin.h:315
rcu_note_context_switch+0xa8/0x4e8" warning. It took me half a month
to locate this issue. Ultimately, I discovered that the lack of upper
overflow detection mechanism in migrate_disable() was the root cause,
leading to a significant amount of time spent on problem localization.
If the upper overflow detection mechanism was added to migrate_disable(),
the root cause could be very quickly and easily identified.
Effect
======
Using WARN_ON_ONCE() to check if 'migration_disabled' is upper overflow
can help developers identify the issue quickly.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Peilin He<he.peilin@zte.com.cn>
Signed-off-by: xu xin <xu.xin16@zte.com.cn>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Yunkai Zhang <zhang.yunkai@zte.com.cn>
Reviewed-by: Qiang Tu <tu.qiang35@zte.com.cn>
Reviewed-by: Kun Jiang <jiang.kun2@zte.com.cn>
Reviewed-by: Fan Yu <fan.yu9@zte.com.cn>
Link: https://lkml.kernel.org/r/20240716104244764N2jD8gnBpnsLjCDnQGQ8c@zte.com.cn
When creating a new task, we initialize vruntime of the newly task at
sched_cgroup_fork(). However, the timing of executing this action is too
early and may not be accurate.
Because it uses current CPU to init the vruntime, but the new task
actually runs on the cpu which be assigned at wake_up_new_task().
To optimize this case, we pass ENQUEUE_INITIAL flag to activate_task()
in wake_up_new_task(), in this way, when place_entity is called in
enqueue_entity(), the vruntime of the new task will be initialized.
In addition, place_entity() in task_fork_fair() was introduced for two
reasons:
1. Previously, the __enqueue_entity() was in task_new_fair(),
in order to provide vruntime for enqueueing the newly task, the
vruntime assignment equation "se->vruntime = cfs_rq->min_vruntime" was
introduced by commit e9acbff648 ("sched: introduce se->vruntime").
This is the initial state of place_entity().
2. commit 4d78e7b656 ("sched: new task placement for vruntime") added
child_runs_first task placement feature which based on vruntime, this
also requires the new task's vruntime value.
After removing the child_runs_first and enqueue_entity() from
task_fork_fair(), this place_entity() no longer makes sense, so remove
it also.
Signed-off-by: Zhang Qiao <zhangqiao22@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20240627133359.1370598-1-zhangqiao22@huawei.com
I got the following warn report while doing stress test:
jump label: negative count!
WARNING: CPU: 3 PID: 38 at kernel/jump_label.c:263 static_key_slow_try_dec+0x9d/0xb0
Call Trace:
<TASK>
__static_key_slow_dec_cpuslocked+0x16/0x70
sched_cpu_deactivate+0x26e/0x2a0
cpuhp_invoke_callback+0x3ad/0x10d0
cpuhp_thread_fun+0x3f5/0x680
smpboot_thread_fn+0x56d/0x8d0
kthread+0x309/0x400
ret_from_fork+0x41/0x70
ret_from_fork_asm+0x1b/0x30
</TASK>
Because when cpuset_cpu_inactive() fails in sched_cpu_deactivate(),
the cpu offline failed, but sched_smt_present is decremented before
calling sched_cpu_deactivate(), it leads to unbalanced dec/inc, so
fix it by incrementing sched_smt_present in the error path.
Fixes: c5511d03ec ("sched/smt: Make sched_smt_present track topology")
Cc: stable@kernel.org
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Chen Yu <yu.c.chen@intel.com>
Reviewed-by: Tim Chen <tim.c.chen@linux.intel.com>
Link: https://lore.kernel.org/r/20240703031610.587047-3-yangyingliang@huaweicloud.com
In extreme test scenarios:
the 14th field utime in /proc/xx/stat is greater than sum_exec_runtime,
utime = 18446744073709518790 ns, rtime = 135989749728000 ns
In cputime_adjust() process, stime is greater than rtime due to
mul_u64_u64_div_u64() precision problem.
before call mul_u64_u64_div_u64(),
stime = 175136586720000, rtime = 135989749728000, utime = 1416780000.
after call mul_u64_u64_div_u64(),
stime = 135989949653530
unsigned reversion occurs because rtime is less than stime.
utime = rtime - stime = 135989749728000 - 135989949653530
= -199925530
= (u64)18446744073709518790
Trigger condition:
1). User task run in kernel mode most of time
2). ARM64 architecture
3). TICK_CPU_ACCOUNTING=y
CONFIG_VIRT_CPU_ACCOUNTING_NATIVE is not set
Fix mul_u64_u64_div_u64() conversion precision by reset stime to rtime
Fixes: 3dc167ba57 ("sched/cputime: Improve cputime_adjust()")
Signed-off-by: Zheng Zucheng <zhengzucheng@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20240726023235.217771-1-zhengzucheng@huawei.com
- Stop testing the group->parent pointer as it is not guaranteed to be
stable over a chain of operations by design. This includes a warning
which would be nice to have but it produces false positives due to
the racy nature of the check.
- Plug a race between CPUs going in and out of idle and a CPU hotplug
operation. The latter can create and connect a new hierarchy level
which is missed in the concurrent updates of CPUs which go into idle.
As a result the events of such a CPU might not be processed and
timers go stale.
Cure it by splitting the hotplug operation into a prepare and online
callback. The prepare callback is guaranteed to run on an online and
therefore active CPU. This CPU updates the hierarchy and being online
ensures that there is always at least one migrator active which
handles the modified hierarchy correctly when going idle. The online
callback which runs on the incoming CPU then just marks the CPU
active and brings it into operation.
- Improve tracing and polish the code further so it is more obvious
what's going on.
-----BEGIN PGP SIGNATURE-----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=G1Lg
-----END PGP SIGNATURE-----
Merge tag 'timers-urgent-2024-07-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer migration updates from Thomas Gleixner:
"Fixes and minor updates for the timer migration code:
- Stop testing the group->parent pointer as it is not guaranteed to
be stable over a chain of operations by design.
This includes a warning which would be nice to have but it produces
false positives due to the racy nature of the check.
- Plug a race between CPUs going in and out of idle and a CPU hotplug
operation. The latter can create and connect a new hierarchy level
which is missed in the concurrent updates of CPUs which go into
idle. As a result the events of such a CPU might not be processed
and timers go stale.
Cure it by splitting the hotplug operation into a prepare and
online callback. The prepare callback is guaranteed to run on an
online and therefore active CPU. This CPU updates the hierarchy and
being online ensures that there is always at least one migrator
active which handles the modified hierarchy correctly when going
idle. The online callback which runs on the incoming CPU then just
marks the CPU active and brings it into operation.
- Improve tracing and polish the code further so it is more obvious
what's going on"
* tag 'timers-urgent-2024-07-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timers/migration: Fix grammar in comment
timers/migration: Spare write when nothing changed
timers/migration: Rename childmask by groupmask to make naming more obvious
timers/migration: Read childmask and parent pointer in a single place
timers/migration: Use a single struct for hierarchy walk data
timers/migration: Improve tracing
timers/migration: Move hierarchy setup into cpuhotplug prepare callback
timers/migration: Do not rely always on group->parent
catching COVID, so relatively short PR. Including fixes from bpf
and netfilter.
Current release - regressions:
- tcp: process the 3rd ACK with sk_socket for TFO and MPTCP
Current release - new code bugs:
- l2tp: protect session IDR and tunnel session list with one lock,
make sure the state is coherent to avoid a warning
- eth: bnxt_en: update xdp_rxq_info in queue restart logic
- eth: airoha: fix location of the MBI_RX_AGE_SEL_MASK field
Previous releases - regressions:
- xsk: require XDP_UMEM_TX_METADATA_LEN to actuate tx_metadata_len,
the field reuses previously un-validated pad
Previous releases - always broken:
- tap/tun: drop short frames to prevent crashes later in the stack
- eth: ice: add a per-VF limit on number of FDIR filters
- af_unix: disable MSG_OOB handling for sockets in sockmap/sockhash
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
-----BEGIN PGP SIGNATURE-----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=9OsH
-----END PGP SIGNATURE-----
Merge tag 'net-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Including fixes from bpf and netfilter.
A lot of networking people were at a conference last week, busy
catching COVID, so relatively short PR.
Current release - regressions:
- tcp: process the 3rd ACK with sk_socket for TFO and MPTCP
Current release - new code bugs:
- l2tp: protect session IDR and tunnel session list with one lock,
make sure the state is coherent to avoid a warning
- eth: bnxt_en: update xdp_rxq_info in queue restart logic
- eth: airoha: fix location of the MBI_RX_AGE_SEL_MASK field
Previous releases - regressions:
- xsk: require XDP_UMEM_TX_METADATA_LEN to actuate tx_metadata_len,
the field reuses previously un-validated pad
Previous releases - always broken:
- tap/tun: drop short frames to prevent crashes later in the stack
- eth: ice: add a per-VF limit on number of FDIR filters
- af_unix: disable MSG_OOB handling for sockets in sockmap/sockhash"
* tag 'net-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (34 commits)
tun: add missing verification for short frame
tap: add missing verification for short frame
mISDN: Fix a use after free in hfcmulti_tx()
gve: Fix an edge case for TSO skb validity check
bnxt_en: update xdp_rxq_info in queue restart logic
tcp: process the 3rd ACK with sk_socket for TFO/MPTCP
selftests/bpf: Add XDP_UMEM_TX_METADATA_LEN to XSK TX metadata test
xsk: Require XDP_UMEM_TX_METADATA_LEN to actuate tx_metadata_len
bpf: Fix a segment issue when downgrading gso_size
net: mediatek: Fix potential NULL pointer dereference in dummy net_device handling
MAINTAINERS: make Breno the netconsole maintainer
MAINTAINERS: Update bonding entry
net: nexthop: Initialize all fields in dumped nexthops
net: stmmac: Correct byte order of perfect_match
selftests: forwarding: skip if kernel not support setting bridge fdb learning limit
tipc: Return non-zero value from tipc_udp_addr2str() on error
netfilter: nft_set_pipapo_avx2: disable softinterrupts
ice: Fix recipe read procedure
ice: Add a per-VF limit on number of FDIR filters
net: bonding: correctly annotate RCU in bond_should_notify_peers()
...
