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* [PATCH] cpufreq: Send CPUFREQ_CREATE_POLICY notification after the perf domain creation.
@ 2023-01-15 11:02 Vincent Wang
  2023-01-17  8:43 ` kernel test robot
  0 siblings, 1 reply; 5+ messages in thread
From: Vincent Wang @ 2023-01-15 11:02 UTC (permalink / raw)
  To: rafael, viresh.kumar; +Cc: linux-pm, linux-kernel, Vincent Wang

From: Vincent Wang <vincentwang3@lenovo.com>

We found the following issue during kernel boot on android phone:

[    1.325272][    T1] cpu cpu0: EM: created perf domain
[    1.329317][    T1] cpu cpu4: EM: created perf domain
[    1.337597][   T76] pd_init: no EM found for CPU7
[    1.350849][    T1] cpu cpu7: EM: created perf domain

pd init for cluster2 is executed in a kworker thread and
is earlier than the perf domain creation for cluster2.

pd_init() is called from the cpufreq notification of
CPUFREQ_CREATE_POLICY in cpufreq_online(), which is earlier
than that cpufreq_driver->register_em() is called.

To avoid this issue, cpufreq notification should be sent after
the perf domain creation.

Signed-off-by: Vincent Wang <vincentwang3@lenovo.com>
---
 drivers/cpufreq/cpufreq.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 7e56a42750ea..9e67df4fc334 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1506,6 +1506,9 @@ static int cpufreq_online(unsigned int cpu)
 		 */
 		if (cpufreq_driver->register_em)
 			cpufreq_driver->register_em(policy);
+
+		blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
+				CPUFREQ_CREATE_POLICY, policy);
 	}
 
 	ret = cpufreq_init_policy(policy);
-- 
2.25.1


^ permalink raw reply related	[flat|nested] 5+ messages in thread
* [PATCH] cpufreq: Send CPUFREQ_CREATE_POLICY notification after the perf domain creation.
@ 2023-01-15 23:52 Vincent Wang
  2023-01-16  4:07 ` Viresh Kumar
  2023-01-17 13:30 ` Rafael J. Wysocki
  0 siblings, 2 replies; 5+ messages in thread
From: Vincent Wang @ 2023-01-15 23:52 UTC (permalink / raw)
  To: rafael, viresh.kumar; +Cc: linux-pm, linux-kernel, Vincent Wang

From: Vincent Wang <vincentwang3@lenovo.com>

We found the following issue during kernel boot on android phone:

[    1.325272][    T1] cpu cpu0: EM: created perf domain
[    1.329317][    T1] cpu cpu4: EM: created perf domain
[    1.337597][   T76] pd_init: no EM found for CPU7
[    1.350849][    T1] cpu cpu7: EM: created perf domain

pd init for cluster2 is executed in a kworker thread and
is earlier than the perf domain creation for cluster2.

pd_init() is called from the cpufreq notification of
CPUFREQ_CREATE_POLICY in cpufreq_online(), which is earlier
than that cpufreq_driver->register_em() is called.

To avoid this issue, cpufreq notification should be sent after
the perf domain creation.

Signed-off-by: Vincent Wang <vincentwang3@lenovo.com>
---
 drivers/cpufreq/cpufreq.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 7e56a42750ea..af8836069398 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1430,9 +1430,6 @@ static int cpufreq_online(unsigned int cpu)
 			policy->max_freq_req = NULL;
 			goto out_destroy_policy;
 		}
-
-		blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
-				CPUFREQ_CREATE_POLICY, policy);
 	}
 
 	if (cpufreq_driver->get && has_target()) {
@@ -1506,6 +1503,9 @@ static int cpufreq_online(unsigned int cpu)
 		 */
 		if (cpufreq_driver->register_em)
 			cpufreq_driver->register_em(policy);
+
+		blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
+				CPUFREQ_CREATE_POLICY, policy);
 	}
 
 	ret = cpufreq_init_policy(policy);
-- 
2.25.1


^ permalink raw reply related	[flat|nested] 5+ messages in thread
end of thread, other threads:[~2023-01-17 13:30 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2023-01-15 11:02 [PATCH] cpufreq: Send CPUFREQ_CREATE_POLICY notification after the perf domain creation Vincent Wang
2023-01-17  8:43 ` kernel test robot
  -- strict thread matches above, loose matches on Subject: below --
2023-01-15 23:52 Vincent Wang
2023-01-16  4:07 ` Viresh Kumar
2023-01-17 13:30 ` Rafael J. Wysocki

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