From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Date: Thu, 21 Mar 2024 19:29:43 +0000 (+0100)
Subject: cpufreq: intel_pstate: Drop redundant locking from intel_pstate_driver_cleanup()
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=f186b2dace86f36cc08872b693185eaf71128898;p=linux.git

cpufreq: intel_pstate: Drop redundant locking from intel_pstate_driver_cleanup()

Remove the spinlock locking from intel_pstate_driver_cleanup() as it is
not necessary because no other code accessing all_cpu_data[] can run in
parallel with that function.

Had the locking been necessary, though, it would have been incorrect
because the lock in question is acquired from a hardirq handler and
it cannot be acquired from thread context without disabling interrupts.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index dbbf299f42197..bcbeed92458d4 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -3135,10 +3135,8 @@ static void intel_pstate_driver_cleanup(void)
 			if (intel_pstate_driver == &intel_pstate)
 				intel_pstate_clear_update_util_hook(cpu);
 
-			spin_lock(&hwp_notify_lock);
 			kfree(all_cpu_data[cpu]);
 			WRITE_ONCE(all_cpu_data[cpu], NULL);
-			spin_unlock(&hwp_notify_lock);
 		}
 	}
 	cpus_read_unlock();