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release 6.12.4 (preliminary)

This commit is contained in:
2024-12-10 06:44:25 +03:00
parent 9debc8729c
commit 407e7bac82
246 changed files with 4681 additions and 5758 deletions

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@@ -1,26 +1,35 @@
From d31e903a364802c068ff23bdd448cc70eda71a7c Mon Sep 17 00:00:00 2001
From 3d722d5259babc1650ab6cb1a8bbf27863af75f2 Mon Sep 17 00:00:00 2001
From: Christian Loehle <christian.loehle@arm.com>
Date: Thu, 5 Sep 2024 10:26:38 +0100
Subject: cpuidle: menu: Remove iowait influence
Remove CPU iowaiters influence on idle state selection.
Remove the menu notion of performance multiplier which increased with
the number of tasks that went to iowait sleep on this CPU and haven't
woken up yet.
Relying on iowait for cpuidle is problematic for a few reasons:
1. There is no guarantee that an iowaiting task will wake up on the
same CPU.
2. The task being in iowait says nothing about the idle duration, we
could be selecting shallower states for a long time.
3. The task being in iowait doesn't always imply a performance hit
with increased latency.
4. If there is such a performance hit, the number of iowaiting tasks
doesn't directly correlate.
5. The definition of iowait altogether is vague at best, it is
sprinkled across kernel code.
1. There is no guarantee that an iowaiting task will wake up on the
same CPU.
2. The task being in iowait says nothing about the idle duration, we
could be selecting shallower states for a long time.
3. The task being in iowait doesn't always imply a performance hit
with increased latency.
4. If there is such a performance hit, the number of iowaiting tasks
doesn't directly correlate.
5. The definition of iowait altogether is vague at best, it is
sprinkled across kernel code.
Signed-off-by: Christian Loehle <christian.loehle@arm.com>
Link: https://patch.msgid.link/20240905092645.2885200-2-christian.loehle@arm.com
[ rjw: Minor edits in the changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
drivers/cpuidle/governors/menu.c | 76 ++++----------------------------
1 file changed, 9 insertions(+), 67 deletions(-)