[PATCH V2] cpufreq: Fix per-policy boost behavior on SoCs using cpufreq_boost_set_sw

From: Sibi Sankar
Date: Fri Mar 08 2024 - 05:39:36 EST


In the existing code, per-policy flags doesn't have any impact i.e.
if cpufreq_driver boost is enabled and one or more of the per-policy
boost is disabled, the cpufreq driver will behave as if boost is
enabled. Fix this by incorporating per-policy boost flag in the policy->max
calculus used in cpufreq_frequency_table_cpuinfo and setting the default
per-policy boost to mirror the cpufreq_driver boost flag.

Fixes: 218a06a79d9a ("cpufreq: Support per-policy performance boost")
Reported-by: Dietmar Eggemann <dietmar.eggemann@xxxxxxx>
Signed-off-by: Sibi Sankar <quic_sibis@xxxxxxxxxxx>
---

v2:
* Enable per-policy boost flag in the core instead. [Viresh]
* Add more details regarding the bug. [Viresh]
* Drop cover-letter and patch 2.

Logs reported-by Dietmar Eggemann:
https://lore.kernel.org/lkml/265e5f2c-9b45-420f-89b1-44369aeb8418@xxxxxxx/

drivers/cpufreq/cpufreq.c | 19 +++++++++++++------
drivers/cpufreq/freq_table.c | 2 +-
2 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index f6f8d7f450e7..c04b2ba2993a 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -653,14 +653,16 @@ static ssize_t store_local_boost(struct cpufreq_policy *policy,
if (policy->boost_enabled == enable)
return count;

+ policy->boost_enabled = enable;
+
cpus_read_lock();
ret = cpufreq_driver->set_boost(policy, enable);
cpus_read_unlock();

- if (ret)
+ if (ret) {
+ policy->boost_enabled = !policy->boost_enabled;
return ret;
-
- policy->boost_enabled = enable;
+ }

return count;
}
@@ -1428,6 +1430,10 @@ static int cpufreq_online(unsigned int cpu)
goto out_free_policy;
}

+ /* Let the per-policy boost flag mirror the cpufreq_driver boost during init */
+ if (cpufreq_driver->boost_enabled)
+ policy->boost_enabled = policy_has_boost_freq(policy) ? true : false;
+
/*
* The initialization has succeeded and the policy is online.
* If there is a problem with its frequency table, take it
@@ -2769,11 +2775,12 @@ int cpufreq_boost_trigger_state(int state)

cpus_read_lock();
for_each_active_policy(policy) {
+ policy->boost_enabled = state;
ret = cpufreq_driver->set_boost(policy, state);
- if (ret)
+ if (ret) {
+ policy->boost_enabled = !policy->boost_enabled;
goto err_reset_state;
-
- policy->boost_enabled = state;
+ }
}
cpus_read_unlock();

diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c
index c4d4643b6ca6..c17dc51a5a02 100644
--- a/drivers/cpufreq/freq_table.c
+++ b/drivers/cpufreq/freq_table.c
@@ -40,7 +40,7 @@ int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
cpufreq_for_each_valid_entry(pos, table) {
freq = pos->frequency;

- if (!cpufreq_boost_enabled()
+ if ((!cpufreq_boost_enabled() || !policy->boost_enabled)
&& (pos->flags & CPUFREQ_BOOST_FREQ))
continue;

--
2.34.1