This is a note to let you know that I've just added the patch titled
cpufreq: amd-pstate: Update policy->cur in amd_pstate_adjust_perf()
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
cpufreq-amd-pstate-update-policy-cur-in-amd_pstate_adjust_perf.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 3bf8c6307bad5c0cc09cde982e146d847859b651 Mon Sep 17 00:00:00 2001
From: Wyes Karny <wyes.karny@xxxxxxx>
Date: Thu, 18 May 2023 05:58:19 +0000
Subject: cpufreq: amd-pstate: Update policy->cur in amd_pstate_adjust_perf()
From: Wyes Karny <wyes.karny@xxxxxxx>
commit 3bf8c6307bad5c0cc09cde982e146d847859b651 upstream.
Driver should update policy->cur after updating the frequency.
Currently amd_pstate doesn't update policy->cur when `adjust_perf`
is used. Which causes /proc/cpuinfo to show wrong cpu frequency.
Fix this by updating policy->cur with correct frequency value in
adjust_perf function callback.
- Before the fix: (setting min freq to 1.5 MHz)
[root@amd]# cat /proc/cpuinfo | grep "cpu MHz" | sort | uniq --count
1 cpu MHz : 1777.016
1 cpu MHz : 1797.160
1 cpu MHz : 1797.270
189 cpu MHz : 400.000
- After the fix: (setting min freq to 1.5 MHz)
[root@amd]# cat /proc/cpuinfo | grep "cpu MHz" | sort | uniq --count
1 cpu MHz : 1753.353
1 cpu MHz : 1756.838
1 cpu MHz : 1776.466
1 cpu MHz : 1776.873
1 cpu MHz : 1777.308
1 cpu MHz : 1779.900
183 cpu MHz : 1805.231
1 cpu MHz : 1956.815
1 cpu MHz : 2246.203
1 cpu MHz : 2259.984
Fixes: 1d215f0319c2 ("cpufreq: amd-pstate: Add fast switch function for AMD P-State")
Signed-off-by: Wyes Karny <wyes.karny@xxxxxxx>
[ rjw: Subject edits ]
Cc: 5.17+ <stable@xxxxxxxxxxxxxxx> # 5.17+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/cpufreq/amd-pstate.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -284,12 +284,14 @@ static void amd_pstate_adjust_perf(unsig
unsigned long capacity)
{
unsigned long max_perf, min_perf, des_perf,
- cap_perf, lowest_nonlinear_perf;
+ cap_perf, lowest_nonlinear_perf, max_freq;
struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
struct amd_cpudata *cpudata = policy->driver_data;
+ unsigned int target_freq;
cap_perf = READ_ONCE(cpudata->highest_perf);
lowest_nonlinear_perf = READ_ONCE(cpudata->lowest_nonlinear_perf);
+ max_freq = READ_ONCE(cpudata->max_freq);
des_perf = cap_perf;
if (target_perf < capacity)
@@ -306,6 +308,10 @@ static void amd_pstate_adjust_perf(unsig
if (max_perf < min_perf)
max_perf = min_perf;
+ des_perf = clamp_t(unsigned long, des_perf, min_perf, max_perf);
+ target_freq = div_u64(des_perf * max_freq, max_perf);
+ policy->cur = target_freq;
+
amd_pstate_update(cpudata, min_perf, des_perf, max_perf, true);
cpufreq_cpu_put(policy);
}
Patches currently in stable-queue which might be from wyes.karny@xxxxxxx are
queue-6.1/cpufreq-amd-pstate-add-fast_switch-callback.patch
queue-6.1/cpufreq-amd-pstate-update-policy-cur-in-amd_pstate_adjust_perf.patch
