linux.git/kernel/sched/pelt.c, branch v6.10

sched/cpufreq: Rename arch_update_thermal_pressure() => arch_update_hw_pressure()

2024-04-24T10:08:01+00:00

Now that cpufreq provides a pressure value to the scheduler, rename
arch_update_thermal_pressure into HW pressure to reflect that it returns
a pressure applied by HW (i.e. with a high frequency change) and not
always related to thermal mitigation but also generated by max current
limitation as an example. Such high frequency signal needs filtering to be
smoothed and provide an value that reflects the average available capacity
into the scheduler time scale.

Signed-off-by: Vincent Guittot 
Signed-off-by: Ingo Molnar 
Tested-by: Lukasz Luba 
Reviewed-by: Qais Yousef 
Reviewed-by: Lukasz Luba 
Link: https://lore.kernel.org/r/20240326091616.3696851-5-vincent.guittot@linaro.org

sched/balancing: Fix a couple of outdated function names in comments

2024-03-12T11:00:01+00:00

The 'idle_balance()' function hasn't existed for years, and there's no
load_balance_newidle() either - both are sched_balance_newidle() today.

Reported-by: Honglei Wang 
Signed-off-by: Ingo Molnar 
Link: https://lore.kernel.org/r/ZfAwNufbiyt/5biu@gmail.com

sched/balancing: Rename update_blocked_averages() => sched_balance_update_blocked_averages()

2024-03-12T11:00:00+00:00

Standardize scheduler load-balancing function names on the
sched_balance_() prefix.

Signed-off-by: Ingo Molnar 
Reviewed-by: Shrikanth Hegde 
Link: https://lore.kernel.org/r/20240308111819.1101550-10-mingo@kernel.org

sched: Make PELT acronym definition searchable

2023-10-13T07:56:30+00:00

The PELT acronym definition can be found right at the top of
kernel/sched/pelt.c (of course), but it cannot be found through use of

grep -r PELT kernel/sched/

Add the acronym "(PELT)" after "Per Entity Load Tracking" at the top of
the source file.

Signed-off-by: Mathieu Desnoyers 
Signed-off-by: Peter Zijlstra (Intel) 
Link: https://lkml.kernel.org/r/20231012125824.1260774-1-mathieu.desnoyers@efficios.com

sched/headers: Introduce kernel/sched/build_policy.c and build multiple .c files there

2022-02-23T09:58:33+00:00

Similarly to kernel/sched/build_utility.c, collect all 'scheduling policy' related
source code files into kernel/sched/build_policy.c:

    kernel/sched/idle.c

    kernel/sched/rt.c

    kernel/sched/cpudeadline.c
    kernel/sched/pelt.c

    kernel/sched/cputime.c
    kernel/sched/deadline.c

With the exception of fair.c, which we continue to build as a separate file
for build efficiency and parallelism reasons.

Signed-off-by: Ingo Molnar 
Reviewed-by: Peter Zijlstra

sched: Fix various typos

2021-03-21T23:11:52+00:00

Fix ~42 single-word typos in scheduler code comments.

We have accumulated a few fun ones over the years. :-)

Signed-off-by: Ingo Molnar 
Cc: Peter Zijlstra 
Cc: Mike Galbraith 
Cc: Juri Lelli 
Cc: Vincent Guittot 
Cc: Dietmar Eggemann 
Cc: Steven Rostedt 
Cc: Ben Segall 
Cc: Mel Gorman 
Cc: linux-kernel@vger.kernel.org

sched: Add a tracepoint to track rq->nr_running

2020-07-08T09:39:02+00:00

Add a bare tracepoint trace_sched_update_nr_running_tp which tracks
->nr_running CPU's rq. This is used to accurately trace this data and
provide a visualization of scheduler imbalances in, for example, the
form of a heat map.  The tracepoint is accessed by loading an external
kernel module. An example module (forked from Qais' module and including
the pelt related tracepoints) can be found at:

  https://github.com/auldp/tracepoints-helpers.git

A script to turn the trace-cmd report output into a heatmap plot can be
found at:

  https://github.com/jirvoz/plot-nr-running

The tracepoints are added to add_nr_running() and sub_nr_running() which
are in kernel/sched/sched.h. In order to avoid CREATE_TRACE_POINTS in
the header a wrapper call is used and the trace/events/sched.h include
is moved before sched.h in kernel/sched/core.

Signed-off-by: Phil Auld 
Signed-off-by: Peter Zijlstra (Intel) 
Link: https://lkml.kernel.org/r/20200629192303.GC120228@lorien.usersys.redhat.com

sched/pelt: Cleanup PELT divider

2020-06-15T12:10:06+00:00

Factorize in a single place the calculation of the divider to be used to
to compute *_avg from *_sum value

Suggested-by: Dietmar Eggemann 
Signed-off-by: Vincent Guittot 
Signed-off-by: Peter Zijlstra (Intel) 
Link: https://lkml.kernel.org/r/20200612154703.23555-1-vincent.guittot@linaro.org

sched/pelt: Remove redundant cap_scale() definition

2020-06-15T12:10:01+00:00

Besides in PELT cap_scale() is used in the Deadline scheduler class for
scale-invariant bandwidth enforcement.
Remove the cap_scale() definition in kernel/sched/pelt.c and keep the
one in kernel/sched/sched.h.

Signed-off-by: Dietmar Eggemann 
Signed-off-by: Peter Zijlstra (Intel) 
Reviewed-by: Vincent Guittot 
Link: https://lkml.kernel.org/r/20200603080304.16548-2-dietmar.eggemann@arm.com

sched/pelt: Sync util/runnable_sum with PELT window when propagating

2020-05-19T18:34:14+00:00

update_tg_cfs_*() propagate the impact of the attach/detach of an entity
down into the cfs_rq hierarchy and must keep the sync with the current pelt
window.

Even if we can't sync child cfs_rq and its group se, we can sync the group
se and its parent cfs_rq with current position in the PELT window. In fact,
we must keep them sync in order to stay also synced with others entities
and group entities that are already attached to the cfs_rq.

Signed-off-by: Vincent Guittot 
Signed-off-by: Peter Zijlstra (Intel) 
Link: https://lkml.kernel.org/r/20200506155301.14288-1-vincent.guittot@linaro.org