linux-kernel - [PATCH 0/3] sched/fair: Sort out 'blocked

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Message-ID: <20251202081304.3103393-1-mingo@kernel.org>
Date: Tue,  2 Dec 2025 09:13:01 +0100
From: Ingo Molnar <mingo@...nel.org>
To: linux-kernel@...r.kernel.org
Cc: Peter Zijlstra <peterz@...radead.org>,
	Frederic Weisbecker <frederic@...nel.org>,
	Shrikanth Hegde <sshegde@...ux.ibm.com>,
	Juri Lelli <juri.lelli@...hat.com>,
	Dietmar Eggemann <dietmar.eggemann@....com>,
	Valentin Schneider <vschneid@...hat.com>,
	Vincent Guittot <vincent.guittot@...aro.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Mel Gorman <mgorman@...e.de>,
	Steven Rostedt <rostedt@...dmis.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	Ingo Molnar <mingo@...nel.org>
Subject: [PATCH 0/3] sched/fair: Sort out 'blocked_load*' namespace confusion

There's three separate, independent pieces of logic in the
scheduler that are named 'has_blocked':

   1) nohz.has_blocked,
   2) rq->has_blocked_load - both of these relate to NOHZ balancing,

   3) and cfs_rq_has_blocked(), which operates on SMP load-balancing
      averages.

While reviewing this code I noticed a couple of inconsistencies:

  - nohz.has_blocked sometimes gets handled via a local variable
    that is named 'has_blocked_load' - but it's the runqueue
    that has the has_blocked_load field, not the nohz structure ...

  - The cfs_rq_has_blocked() function does SMP load-balancing and
    has no relation to NOHZ has_blocked logic.

  - The update_blocked_load_status() function, which sets the
    rq->has_blocked_load field, has a parameter named 'has_blocked',
    but that's the field name of the nohz structure.

To sort all of this out, standardize on 3 distinct patterns:

  (1) nohz.has_blocked related functions and variables use the
      'has_blocked' nomenclature,

  (2) rq->has_blocked_load related functions and variables use
      'has_blocked_load',

  (3) and cfs_rq_has_blocked() uses 'has_blocked_load_avg'.

This series implements (1), (2) and (3) via three patches.

The end result becomes a lot more greppable, as the following
'git grep' commands:

  git grep 'has_blocked\>'                kernel/sched/
  git grep 'has_blocked_load\>'           kernel/sched/
  git grep 'has_blocked_load_avg\>'       kernel/sched/

... will now output only the respective relevant lines.

No change in functionality.

Thanks,

	Ingo

================

Ingo Molnar (3):
  sched/fair: Rename the 'has_blocked_load' local variable to 'has_blocked' in _nohz_idle_balance()
  sched/fair: Rename the 'has_blocked' parameter in update_blocked_load_status() to 'has_blocked_load'
  sched/fair: Rename cfs_rq_has_blocked() => cfs_rq_has_blocked_load_avg()

 kernel/sched/fair.c | 22 +++++++++++-----------
 1 file changed, 11 insertions(+), 11 deletions(-)