linux-kernel - [PATCH 03/12] cpufreq/amd-pstate: Modify the min_perf calculation in adjust

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Message-ID: <20250205112523.201101-4-dhananjay.ugwekar@amd.com>
Date: Wed, 5 Feb 2025 11:25:14 +0000
From: Dhananjay Ugwekar <dhananjay.ugwekar@....com>
To: <gautham.shenoy@....com>, <mario.limonciello@....com>,
	<rafael@...nel.org>, <viresh.kumar@...aro.org>
CC: <linux-kernel@...r.kernel.org>, <linux-pm@...r.kernel.org>, "Dhananjay
 Ugwekar" <dhananjay.ugwekar@....com>
Subject: [PATCH 03/12] cpufreq/amd-pstate: Modify the min_perf calculation in adjust_perf callback

Instead of setting a fixed floor at lowest_nonlinear_perf, use the
min_limit_perf value, so that it gives the user the freedom to lower the
floor further.

There are two minimum frequency/perf limits that we need to consider in
the adjust_perf callback. One provided by schedutil i.e. the sg_cpu->bw_min
value passed in _min_perf arg, another is the effective value of
min_freq_qos request that is updated in cpudata->min_limit_perf. Modify the
code to use the bigger of these two values.

Signed-off-by: Dhananjay Ugwekar <dhananjay.ugwekar@....com>
---
 drivers/cpufreq/amd-pstate.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 9dc3933bc326..a23fb78a442b 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -672,7 +672,7 @@ static void amd_pstate_adjust_perf(unsigned int cpu,
 				   unsigned long capacity)
 {
 	unsigned long max_perf, min_perf, des_perf,
-		      cap_perf, lowest_nonlinear_perf;
+		      cap_perf, min_limit_perf;
 	struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
 	struct amd_cpudata *cpudata;
 
@@ -684,20 +684,20 @@ static void amd_pstate_adjust_perf(unsigned int cpu,
 	if (policy->min != cpudata->min_limit_freq || policy->max != cpudata->max_limit_freq)
 		amd_pstate_update_min_max_limit(policy);
 
-
 	cap_perf = READ_ONCE(cpudata->highest_perf);
-	lowest_nonlinear_perf = READ_ONCE(cpudata->lowest_nonlinear_perf);
+	min_limit_perf = READ_ONCE(cpudata->min_limit_perf);
 
 	des_perf = cap_perf;
 	if (target_perf < capacity)
 		des_perf = DIV_ROUND_UP(cap_perf * target_perf, capacity);
 
-	min_perf = READ_ONCE(cpudata->lowest_perf);
 	if (_min_perf < capacity)
 		min_perf = DIV_ROUND_UP(cap_perf * _min_perf, capacity);
+	else
+		min_perf = cap_perf;
 
-	if (min_perf < lowest_nonlinear_perf)
-		min_perf = lowest_nonlinear_perf;
+	if (min_perf < min_limit_perf)
+		min_perf = min_limit_perf;
 
 	max_perf = cpudata->max_limit_perf;
 	if (max_perf < min_perf)
-- 
2.34.1