revert "[CPUFREQ] remove rwsem lock from CPUFREQ_GOV_STOP call (second call site)"

commit accd846698439ba18250e8fd5681af280446b853 upstream.

395913d0b1db37092ea3d9d69b832183b1dd84c5 ("[CPUFREQ] remove rwsem lock
from CPUFREQ_GOV_STOP call (second call site)") is not needed, because
there is no rwsem lock in cpufreq_ondemand and cpufreq_conservative
anymore.  Lock should not be released until the work done.

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=1594

Signed-off-by: Andrej Gelenberg <andrej.gelenberg@udo.edu>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 67bc2ece7b4b508da7855937a01eb388cd33ab5b..295dc63256b815ca0823ad791e7ef68eb8f3f1a4 100644 (file)
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1765,17 +1765,8 @@ static int __cpufreq_set_policy(struct cpufreq_policy *data,
                        dprintk("governor switch\n");
 
                        /* end old governor */
-                       if (data->governor) {
-                               /*
-                                * Need to release the rwsem around governor
-                                * stop due to lock dependency between
-                                * cancel_delayed_work_sync and the read lock
-                                * taken in the delayed work handler.
-                                */
-                               unlock_policy_rwsem_write(data->cpu);
+                       if (data->governor)
                                __cpufreq_governor(data, CPUFREQ_GOV_STOP);
-                               lock_policy_rwsem_write(data->cpu);
-                       }
 
                        /* start new governor */
                        data->governor = policy->governor;