Merge tag 'v6.8-rc4' into x86/percpu, to resolve conflicts and refresh the branch

Conflicts:
arch/x86/include/asm/percpu.h
arch/x86/include/asm/text-patching.h

Signed-off-by: Ingo Molnar <mingo@k

Merge tag 'v6.8-rc4' into x86/percpu, to resolve conflicts and refresh the branch

Conflicts:
arch/x86/include/asm/percpu.h
arch/x86/include/asm/text-patching.h

Signed-off-by: Ingo Molnar <mingo@kernel.org>

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Merge tag 'drm-misc-next-2024-02-08' into msm-next

Merge the drm-misc tree to uprev MSM CI.

Signed-off-by: Rob Clark <robdclark@chromium.org>

Merge drm/drm-next into drm-misc-next

Kickstart 6.9 development cycle.

Signed-off-by: Maxime Ripard <mripard@kernel.org>

Merge branch 'linus' into x86/mm, to refresh the branch and pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge drm/drm-next into drm-xe-next

Sync to v6.8-rc1.

Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>

Merge v6.8-rc1 into drm-misc-fixes

Let's kickstart the 6.8 fix cycle.

Signed-off-by: Maxime Ripard <mripard@kernel.org>

Merge drm/drm-next into drm-intel-next

Backmerge to bring Xe driver to drm-intel-next.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>

Merge tag 'sched-core-2024-01-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler updates from Ingo Molnar:
"Energy scheduling:

- Consolidate how the max compute capacit

Merge tag 'sched-core-2024-01-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler updates from Ingo Molnar:
"Energy scheduling:

- Consolidate how the max compute capacity is used in the scheduler
and how we calculate the frequency for a level of utilization.

- Rework interface between the scheduler and the schedutil governor

- Simplify the util_est logic

Deadline scheduler:

- Work more towards reducing SCHED_DEADLINE starvation of low
priority tasks (e.g., SCHED_OTHER) tasks when higher priority tasks
monopolize CPU cycles, via the introduction of 'deadline servers'
(nested/2-level scheduling).

"Fair servers" to make use of this facility are not introduced yet.

EEVDF:

- Introduce O(1) fastpath for EEVDF task selection

NUMA balancing:

- Tune the NUMA-balancing vma scanning logic some more, to better
distribute the probability of a particular vma getting scanned.

Plus misc fixes, cleanups and updates"

* tag 'sched-core-2024-01-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
sched/fair: Fix tg->load when offlining a CPU
sched/fair: Remove unused 'next_buddy_marked' local variable in check_preempt_wakeup_fair()
sched/fair: Use all little CPUs for CPU-bound workloads
sched/fair: Simplify util_est
sched/fair: Remove SCHED_FEAT(UTIL_EST_FASTUP, true)
arm64/amu: Use capacity_ref_freq() to set AMU ratio
cpufreq/cppc: Set the frequency used for computing the capacity
cpufreq/cppc: Move and rename cppc_cpufreq_{perf_to_khz|khz_to_perf}()
energy_model: Use a fixed reference frequency
cpufreq/schedutil: Use a fixed reference frequency
cpufreq: Use the fixed and coherent frequency for scaling capacity
sched/topology: Add a new arch_scale_freq_ref() method
freezer,sched: Clean saved_state when restoring it during thaw
sched/fair: Update min_vruntime for reweight_entity() correctly
sched/doc: Update documentation after renames and synchronize Chinese version
sched/cpufreq: Rework iowait boost
sched/cpufreq: Rework schedutil governor performance estimation
sched/pelt: Avoid underestimation of task utilization
sched/timers: Explain why idle task schedules out on remote timer enqueue
sched/cpuidle: Comment about timers requirements VS idle handler
...

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sched/fair: Remove SCHED_FEAT(UTIL_EST_FASTUP, true)

sched_feat(UTIL_EST_FASTUP) has been added to easily disable the feature
in order to check for possibly related regressions. After 3 years, it ha

sched/fair: Remove SCHED_FEAT(UTIL_EST_FASTUP, true)

sched_feat(UTIL_EST_FASTUP) has been added to easily disable the feature
in order to check for possibly related regressions. After 3 years, it has
never been used and no regression has been reported. Let's remove it
and make fast increase a permanent behavior.

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Reviewed-by: Hongyan Xia <hongyan.xia2@arm.com>
Reviewed-by: Tang Yizhou <yizhou.tang@shopee.com>
Reviewed-by: Yanteng Si <siyanteng@loongson.cn> [for the Chinese translation]
Reviewed-by: Alex Shi <alexs@kernel.org>
Link: https://lore.kernel.org/r/20231201161652.1241695-2-vincent.guittot@linaro.org

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Merge remote-tracking branch 'torvalds/master' into perf-tools-next

To pick up fixes that went thru perf-tools for v6.7 and to get in sync
with upstream to check for drift in the copies of headers,

Merge remote-tracking branch 'torvalds/master' into perf-tools-next

To pick up fixes that went thru perf-tools for v6.7 and to get in sync
with upstream to check for drift in the copies of headers, etc.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

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Merge drm/drm-next into drm-misc-next

Let's kickstart the v6.8 release cycle.

Signed-off-by: Maxime Ripard <mripard@kernel.org>

Merge branch 'tip/perf/urgent'

Avoid conflicts, base on fixes.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>

Merge tag 'sched-core-2023-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler updates from Ingo Molnar:
"Fair scheduler (SCHED_OTHER) improvements:
- Remove the old a

Merge tag 'sched-core-2023-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler updates from Ingo Molnar:
"Fair scheduler (SCHED_OTHER) improvements:
- Remove the old and now unused SIS_PROP code & option
- Scan cluster before LLC in the wake-up path
- Use candidate prev/recent_used CPU if scanning failed for cluster
wakeup

NUMA scheduling improvements:
- Improve the VMA access-PID code to better skip/scan VMAs
- Extend tracing to cover VMA-skipping decisions
- Improve/fix the recently introduced sched_numa_find_nth_cpu() code
- Generalize numa_map_to_online_node()

Energy scheduling improvements:
- Remove the EM_MAX_COMPLEXITY limit
- Add tracepoints to track energy computation
- Make the behavior of the 'sched_energy_aware' sysctl more
consistent
- Consolidate and clean up access to a CPU's max compute capacity
- Fix uclamp code corner cases

RT scheduling improvements:
- Drive dl_rq->overloaded with dl_rq->pushable_dl_tasks updates
- Drive the ->rto_mask with rt_rq->pushable_tasks updates

Scheduler scalability improvements:
- Rate-limit updates to tg->load_avg
- On x86 disable IBRS when CPU is offline to improve single-threaded
performance
- Micro-optimize in_task() and in_interrupt()
- Micro-optimize the PSI code
- Avoid updating PSI triggers and ->rtpoll_total when there are no
state changes

Core scheduler infrastructure improvements:
- Use saved_state to reduce some spurious freezer wakeups
- Bring in a handful of fast-headers improvements to scheduler
headers
- Make the scheduler UAPI headers more widely usable by user-space
- Simplify the control flow of scheduler syscalls by using lock
guards
- Fix sched_setaffinity() vs. CPU hotplug race

Scheduler debuggability improvements:
- Disallow writing invalid values to sched_rt_period_us
- Fix a race in the rq-clock debugging code triggering warnings
- Fix a warning in the bandwidth distribution code
- Micro-optimize in_atomic_preempt_off() checks
- Enforce that the tasklist_lock is held in for_each_thread()
- Print the TGID in sched_show_task()
- Remove the /proc/sys/kernel/sched_child_runs_first sysctl

... and misc cleanups & fixes"

* tag 'sched-core-2023-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (82 commits)
sched/fair: Remove SIS_PROP
sched/fair: Use candidate prev/recent_used CPU if scanning failed for cluster wakeup
sched/fair: Scan cluster before scanning LLC in wake-up path
sched: Add cpus_share_resources API
sched/core: Fix RQCF_ACT_SKIP leak
sched/fair: Remove unused 'curr' argument from pick_next_entity()
sched/nohz: Update comments about NEWILB_KICK
sched/fair: Remove duplicate #include
sched/psi: Update poll => rtpoll in relevant comments
sched: Make PELT acronym definition searchable
sched: Fix stop_one_cpu_nowait() vs hotplug
sched/psi: Bail out early from irq time accounting
sched/topology: Rename 'DIE' domain to 'PKG'
sched/psi: Delete the 'update_total' function parameter from update_triggers()
sched/psi: Avoid updating PSI triggers and ->rtpoll_total when there are no state changes
sched/headers: Remove comment referring to rq::cpu_load, since this has been removed
sched/numa: Complete scanning of inactive VMAs when there is no alternative
sched/numa: Complete scanning of partial VMAs regardless of PID activity
sched/numa: Move up the access pid reset logic
sched/numa: Trace decisions related to skipping VMAs
...

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Merge drm/drm-next into drm-intel-gt-next

Work that needs to land in drm-intel-gt-next depends on two patches only
present in drm-intel-next, absence of which is causing a merge conflict:

3b918f4

Merge drm/drm-next into drm-intel-gt-next

Work that needs to land in drm-intel-gt-next depends on two patches only
present in drm-intel-next, absence of which is causing a merge conflict:

3b918f4f0c8b ("drm/i915/pxp: Optimize GET_PARAM:PXP_STATUS")
ac765b7018f6 ("drm/i915/pxp/mtl: intel_pxp_init_hw needs runtime-pm inside pm-complete")

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

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sched/fair: Remove SIS_PROP

SIS_UTIL seems to work well, lets remove the old thing.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Vincent Guittot <vincent.guittot@linaro.or

sched/fair: Remove SIS_PROP

SIS_UTIL seems to work well, lets remove the old thing.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/20231020134337.GD33965@noisy.programming.kicks-ass.net

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Merge branch 'linus' into smp/core

Pull in upstream to get the fixes so depending changes can be applied.

Merge drm/drm-next into drm-misc-next

Updating drm-misc-next to the state of Linux v6.6-rc2.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge wireless into wireless-next

Resolve several conflicts, mostly between changes/fixes in
wireless and the locking rework in wireless-next. One of
the conflicts actually shows a bug in wireless t

Merge wireless into wireless-next

Resolve several conflicts, mostly between changes/fixes in
wireless and the locking rework in wireless-next. One of
the conflicts actually shows a bug in wireless that we'll
want to fix separately.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>

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Merge tag 'v6.6-rc2' into locking/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge drm/drm-next into drm-intel-next

Sync to v6.6-rc1.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>

Merge drm/drm-fixes into drm-misc-fixes

Forwarding to v6.6-rc1.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge tag 'sched-core-2023-08-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler updates from Ingo Molnar:

- The biggest change is introduction of a new iteration of the

Merge tag 'sched-core-2023-08-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler updates from Ingo Molnar:

- The biggest change is introduction of a new iteration of the
SCHED_FAIR interactivity code: the EEVDF ("Earliest Eligible Virtual
Deadline First") scheduler

EEVDF too is a virtual-time scheduler, with two parameters (weight
and relative deadline), compared to CFS that had weight only. It
completely reworks the base scheduler: placement, preemption, picking
-- everything

LWN.net, as usual, has a terrific writeup about EEVDF:

https://lwn.net/Articles/925371/

Preemption (both tick and wakeup) is driven by testing against a
fresh pick. Because the tree is now effectively an interval tree, and
the selection is no longer the 'leftmost' task, over-scheduling is
less of a problem. A lot of the CFS heuristics are removed or
replaced by more natural latency-space parameters & constructs

In terms of expected performance regressions: we will and can fix
everything where a 'good' workload misbehaves with the new scheduler,
but EEVDF inevitably changes workload scheduling in a binary fashion,
hopefully for the better in the overwhelming majority of cases, but
in some cases it won't, especially in adversarial loads that got
lucky with the previous code, such as some variants of hackbench. We
are trying hard to err on the side of fixing all performance
regressions, but we expect some inevitable post-release iterations of
that process

- Improve load-balancing on hybrid x86 systems: enable cluster
scheduling (again)

- Improve & fix bandwidth-scheduling on nohz systems

- Improve bandwidth-throttling

- Use lock guards to simplify and de-goto-ify control flow

- Misc improvements, cleanups and fixes

* tag 'sched-core-2023-08-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (43 commits)
sched/eevdf/doc: Modify the documented knob to base_slice_ns as well
sched/eevdf: Curb wakeup-preemption
sched: Simplify sched_core_cpu_{starting,deactivate}()
sched: Simplify try_steal_cookie()
sched: Simplify sched_tick_remote()
sched: Simplify sched_exec()
sched: Simplify ttwu()
sched: Simplify wake_up_if_idle()
sched: Simplify: migrate_swap_stop()
sched: Simplify sysctl_sched_uclamp_handler()
sched: Simplify get_nohz_timer_target()
sched/rt: sysctl_sched_rr_timeslice show default timeslice after reset
sched/rt: Fix sysctl_sched_rr_timeslice intial value
sched/fair: Block nohz tick_stop when cfs bandwidth in use
sched, cgroup: Restore meaning to hierarchical_quota
MAINTAINERS: Add Peter explicitly to the psi section
sched/psi: Select KERNFS as needed
sched/topology: Align group flags when removing degenerate domain
sched/fair: remove util_est boosting
sched/fair: Propagate enqueue flags into place_entity()
...

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sched/eevdf: Curb wakeup-preemption

Mike and others noticed that EEVDF does like to over-schedule quite a
bit -- which does hurt performance of a number of benchmarks /
workloads.

In particular, wh

sched/eevdf: Curb wakeup-preemption

Mike and others noticed that EEVDF does like to over-schedule quite a
bit -- which does hurt performance of a number of benchmarks /
workloads.

In particular, what seems to cause over-scheduling is that when lag is
of the same order (or larger) than the request / slice then placement
will not only cause the task to be placed left of current, but also
with a smaller deadline than current, which causes immediate
preemption.

[ notably, lag bounds are relative to HZ ]

Mike suggested we stick to picking 'current' for as long as it's
eligible to run, giving it uninterrupted runtime until it reaches
parity with the pack.

Augment Mike's suggestion by only allowing it to exhaust it's initial
request.

One random data point:

echo NO_RUN_TO_PARITY > /debug/sched/features
perf stat -a -e context-switches --repeat 10 -- perf bench sched messaging -g 20 -t -l 5000

3,723,554 context-switches ( +- 0.56% )
9.5136 +- 0.0394 seconds time elapsed ( +- 0.41% )

echo RUN_TO_PARITY > /debug/sched/features
perf stat -a -e context-switches --repeat 10 -- perf bench sched messaging -g 20 -t -l 5000

2,556,535 context-switches ( +- 0.51% )
9.2427 +- 0.0302 seconds time elapsed ( +- 0.33% )

Suggested-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20230816134059.GC982867@hirez.programming.kicks-ass.net

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Merge branch 'sched/eevdf' into sched/core

Pick up the EEVDF work into the main branch - it's looking good so far.

Conflicts:
kernel/sched/features.h

Signed-off-by: Ingo Molnar <mingo@kernel.org>

sched/fair: Block nohz tick_stop when cfs bandwidth in use

CFS bandwidth limits and NOHZ full don't play well together. Tasks
can easily run well past their quotas before a remote tick does
account

sched/fair: Block nohz tick_stop when cfs bandwidth in use

CFS bandwidth limits and NOHZ full don't play well together. Tasks
can easily run well past their quotas before a remote tick does
accounting. This leads to long, multi-period stalls before such
tasks can run again. Currently, when presented with these conflicting
requirements the scheduler is favoring nohz_full and letting the tick
be stopped. However, nohz tick stopping is already best-effort, there
are a number of conditions that can prevent it, whereas cfs runtime
bandwidth is expected to be enforced.

Make the scheduler favor bandwidth over stopping the tick by setting
TICK_DEP_BIT_SCHED when the only running task is a cfs task with
runtime limit enabled. We use cfs_b->hierarchical_quota to
determine if the task requires the tick.

Add check in pick_next_task_fair() as well since that is where
we have a handle on the task that is actually going to be running.

Add check in sched_can_stop_tick() to cover some edge cases such
as nr_running going from 2->1 and the 1 remains the running task.

Reviewed-By: Ben Segall <bsegall@google.com>
Signed-off-by: Phil Auld <pauld@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230712133357.381137-3-pauld@redhat.com

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