linux-toradex.git/include/linux/sched/topology.h, branch v6.15-rc4

sched/debug: Make CONFIG_SCHED_DEBUG functionality unconditional

2025-03-19T21:20:53+00:00

All the big Linux distros enable CONFIG_SCHED_DEBUG, because
the various features it provides help not just with kernel
development, but with system administration and user-space
software development as well.

Reflect this reality and enable this functionality
unconditionally.

Signed-off-by: Ingo Molnar 
Tested-by: Shrikanth Hegde 
Cc: Peter Zijlstra 
Cc: Juri Lelli 
Cc: Vincent Guittot 
Cc: Dietmar Eggemann 
Cc: Steven Rostedt 
Cc: Ben Segall 
Cc: Mel Gorman 
Cc: Valentin Schneider 
Cc: Linus Torvalds 
Link: https://lore.kernel.org/r/20250317104257.3496611-4-mingo@kernel.org

include/{topology,cpuset}: Move dl_rebuild_rd_accounting to cpuset.h

2025-03-17T10:23:43+00:00

dl_rebuild_rd_accounting() is defined in cpuset.c, so it makes more
sense to move related declarations to cpuset.h.

Implement the move.

Suggested-by: Waiman Long 
Signed-off-by: Juri Lelli 
Signed-off-by: Peter Zijlstra (Intel) 
Reviewed-by: Waiman Long 
Reviewed-by: Valentin Schneider 
Reviewed-by: Dietmar Eggemann 
Tested-by: Waiman Long 
Tested-by: Jon Hunter 
Tested-by: Dietmar Eggemann 
Link: https://lore.kernel.org/r/Z9MSOVMpU7jpVrMU@jlelli-thinkpadt14gen4.remote.csb

sched/topology: Stop exposing partition_sched_domains_locked

2025-03-17T10:23:43+00:00

The are no callers of partition_sched_domains_locked() outside
topology.c.

Stop exposing such function.

Suggested-by: Waiman Long 
Signed-off-by: Juri Lelli 
Signed-off-by: Peter Zijlstra (Intel) 
Reviewed-by: Valentin Schneider 
Reviewed-by: Dietmar Eggemann 
Tested-by: Waiman Long 
Tested-by: Jon Hunter 
Tested-by: Dietmar Eggemann 
Link: https://lore.kernel.org/r/Z9MSC96a8FcqWV3G@jlelli-thinkpadt14gen4.remote.csb

sched/deadline: Rebuild root domain accounting after every update

2025-03-17T10:23:42+00:00

Rebuilding of root domains accounting information (total_bw) is
currently broken on some cases, e.g. suspend/resume on aarch64. Problem
is that the way we keep track of domain changes and try to add bandwidth
back is convoluted and fragile.

Fix it by simplify things by making sure bandwidth accounting is cleared
and completely restored after root domains changes (after root domains
are again stable).

To be sure we always call dl_rebuild_rd_accounting while holding
cpuset_mutex we also add cpuset_reset_sched_domains() wrapper.

Fixes: 53916d5fd3c0 ("sched/deadline: Check bandwidth overflow earlier for hotplug")
Reported-by: Jon Hunter 
Co-developed-by: Waiman Long 
Signed-off-by: Waiman Long 
Signed-off-by: Juri Lelli 
Signed-off-by: Peter Zijlstra (Intel) 
Reviewed-by: Dietmar Eggemann 
Tested-by: Dietmar Eggemann 
Link: https://lore.kernel.org/r/Z9MRfeJKJUOyUSto@jlelli-thinkpadt14gen4.remote.csb

sched: Move sched domain name out of CONFIG_SCHED_DEBUG

2024-12-20T14:31:17+00:00

/proc/schedstat file shows cpu and sched domain level scheduler
statistics. It does not show domain name instead shows domain level.
It will be very useful for tools like `perf sched stats`[1] to
aggragate domain level stats if domain names are shown in /proc/schedstat.
But sched domain name is guarded by CONFIG_SCHED_DEBUG. As per the
discussion[2], move sched domain name out of CONFIG_SCHED_DEBUG.

[1] https://lore.kernel.org/lkml/20241122084452.1064968-1-swapnil.sapkal@amd.com/
[2] https://lore.kernel.org/lkml/fcefeb4d-3acb-462d-9c9b-3df8d927e522@amd.com/

Suggested-by: "Gautham R. Shenoy" 
Signed-off-by: Swapnil Sapkal 
Signed-off-by: Peter Zijlstra (Intel) 
Link: https://lore.kernel.org/r/20241220063224.17767-5-swapnil.sapkal@amd.com

sched: Report the different kinds of imbalances in /proc/schedstat

2024-12-20T14:31:17+00:00

In /proc/schedstat, lb_imbalance reports the sum of imbalances
discovered in sched domains with each call to sched_balance_rq(), which is
not very useful because lb_imbalance does not mention whether the imbalance
is due to load, utilization, nr_tasks or misfit_tasks. Remove this field
from /proc/schedstat.

Currently there is no field in /proc/schedstat to report different types
of imbalances. Introduce new fields in /proc/schedstat to report the
total imbalances in load, utilization, nr_tasks or misfit_tasks.

Added fields to /proc/schedstat:
        - lb_imbalance_load: Total imbalance due to load.
        - lb_imbalance_util: Total imbalance due to utilization.
        - lb_imbalance_task: Total imbalance due to number of tasks.
        - lb_imbalance_misfit: Total imbalance due to misfit tasks.

Signed-off-by: Swapnil Sapkal 
Signed-off-by: Peter Zijlstra (Intel) 
Reviewed-by: Shrikanth Hegde 
Link: https://lore.kernel.org/r/20241220063224.17767-4-swapnil.sapkal@amd.com

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: Rename load_balance() => sched_balance_rq()

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

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

Also load_balance() has become somewhat of a misnomer: historically
it was the first and primary load-balancing function that was called,
but with the introduction of sched domains, it's become a lower
layer function that balances runqueues.

Rename it to sched_balance_rq() accordingly.

Signed-off-by: Ingo Molnar 
Reviewed-by: Shrikanth Hegde 
Link: https://lore.kernel.org/r/20240308111819.1101550-6-mingo@kernel.org

Merge tag 'sched-core-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2024-03-12T01:45:16+00:00

Pull scheduler updates from Ingo Molnar:

 - Fix inconsistency in misfit task load-balancing

 - Fix CPU isolation bugs in the task-wakeup logic

 - Rework and unify the sched_use_asym_prio() and sched_asym_prefer()
   logic

 - Clean up and simplify ->avg_* accesses

 - Misc cleanups and fixes

* tag 'sched-core-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/topology: Rename SD_SHARE_PKG_RESOURCES to SD_SHARE_LLC
  sched/fair: Check the SD_ASYM_PACKING flag in sched_use_asym_prio()
  sched/fair: Rework sched_use_asym_prio() and sched_asym_prefer()
  sched/fair: Remove unused parameter from sched_asym()
  sched/topology: Remove duplicate descriptions from TOPOLOGY_SD_FLAGS
  sched/fair: Simplify the update_sd_pick_busiest() logic
  sched/fair: Do strict inequality check for busiest misfit task group
  sched/fair: Remove unnecessary goto in update_sd_lb_stats()
  sched/fair: Take the scheduling domain into account in select_idle_core()
  sched/fair: Take the scheduling domain into account in select_idle_smt()
  sched/fair: Add READ_ONCE() and use existing helper function to access ->avg_irq
  sched/fair: Use existing helper functions to access ->avg_rt and ->avg_dl
  sched/core: Simplify code by removing duplicate #ifdefs

sched/topology: Rename SD_SHARE_PKG_RESOURCES to SD_SHARE_LLC

2024-02-28T14:43:17+00:00

SD_SHARE_PKG_RESOURCES is a bit of a misnomer: its naming suggests that
it's sharing all 'package resources' - while in reality it's specifically
for sharing the LLC only.

Rename it to SD_SHARE_LLC to reduce confusion.

[ mingo: Rewrote the confusing changelog as well. ]

Suggested-by: Valentin Schneider 
Signed-off-by: Alex Shi 
Signed-off-by: Ingo Molnar 
Reviewed-by: Valentin Schneider 
Reviewed-by: Ricardo Neri 
Reviewed-by: Barry Song 
Link: https://lore.kernel.org/r/20240210113924.1130448-5-alexs@kernel.org