From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Fri, 28 Apr 2023 21:53:30 +0000 (-0700)
Subject: Merge tag 'sched-core-2023-04-27' of git://git.kernel.org/pub/scm/linux/kernel/git... 
X-Git-Tag: v6.6-pxa1908~1340
X-Git-Url: https://git.dujemihanovic.xyz/?a=commitdiff_plain;h=586b222d748e91c619d68e9239654ebc7fed9b0c;p=linux.git

Merge tag 'sched-core-2023-04-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler updates from Ingo Molnar:

 - Allow unprivileged PSI poll()ing

 - Fix performance regression introduced by mm_cid

 - Improve livepatch stalls by adding livepatch task switching to
   cond_resched(). This resolves livepatching busy-loop stalls with
   certain CPU-bound kthreads

 - Improve sched_move_task() performance on autogroup configs

 - On core-scheduling CPUs, avoid selecting throttled tasks to run

 - Misc cleanups, fixes and improvements

* tag 'sched-core-2023-04-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/clock: Fix local_clock() before sched_clock_init()
  sched/rt: Fix bad task migration for rt tasks
  sched: Fix performance regression introduced by mm_cid
  sched/core: Make sched_dynamic_mutex static
  sched/psi: Allow unprivileged polling of N*2s period
  sched/psi: Extract update_triggers side effect
  sched/psi: Rename existing poll members in preparation
  sched/psi: Rearrange polling code in preparation
  sched/fair: Fix inaccurate tally of ttwu_move_affine
  vhost: Fix livepatch timeouts in vhost_worker()
  livepatch,sched: Add livepatch task switching to cond_resched()
  livepatch: Skip task_call_func() for current task
  livepatch: Convert stack entries array to percpu
  sched: Interleave cfs bandwidth timers for improved single thread performance at low utilization
  sched/core: Reduce cost of sched_move_task when config autogroup
  sched/core: Avoid selecting the task that is throttled to run when core-sched enable
  sched/topology: Make sched_energy_mutex,update static
---

586b222d748e91c619d68e9239654ebc7fed9b0c
diff --cc drivers/vhost/vhost.c
index 10bf35a3db6e,822fbdb54c4f..a92af08e7864
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@@ -358,14 -360,13 +358,13 @@@ static int vhost_worker(void *data
  		llist_for_each_entry_safe(work, work_next, node, node) {
  			clear_bit(VHOST_WORK_QUEUED, &work->flags);
  			__set_current_state(TASK_RUNNING);
 -			kcov_remote_start_common(dev->kcov_handle);
 +			kcov_remote_start_common(worker->kcov_handle);
  			work->fn(work);
  			kcov_remote_stop();
- 			if (need_resched())
- 				schedule();
+ 			cond_resched();
  		}
  	}
 -	kthread_unuse_mm(dev->mm);
 +
  	return 0;
  }
  
diff --cc kernel/fork.c
index 4342200d5e2b,ad2ee22272a3..eccb35a85216
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@@ -1308,7 -1179,8 +1313,9 @@@ static struct mm_struct *mm_init(struc
  fail_pcpu:
  	while (i > 0)
  		percpu_counter_destroy(&mm->rss_stat[--i]);
+ 	mm_destroy_cid(mm);
+ fail_cid:
 +	destroy_context(mm);
  fail_nocontext:
  	mm_free_pgd(mm);
  fail_nopgd:
diff --cc kernel/sched/core.c
index 8d2b6742d02c,898fa3bc2765..54c75af24899
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@@ -5268,10 -5284,13 +5286,13 @@@ context_switch(struct rq *rq, struct ta
  
  	/*
  	 * kernel -> kernel   lazy + transfer active
 -	 *   user -> kernel   lazy + mmgrab() active
 +	 *   user -> kernel   lazy + mmgrab_lazy_tlb() active
  	 *
 -	 * kernel ->   user   switch + mmdrop() active
 +	 * kernel ->   user   switch + mmdrop_lazy_tlb() active
  	 *   user ->   user   switch
+ 	 *
+ 	 * switch_mm_cid() needs to be updated if the barriers provided
+ 	 * by context_switch() are modified.
  	 */
  	if (!next->mm) {                                // to kernel
  		enter_lazy_tlb(prev->active_mm, next);