1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
|
From 84a8cbf64731568c0750137ec38091a46b81d502 Mon Sep 17 00:00:00 2001
From: Viresh Kumar <viresh.kumar@linaro.org>
Date: Fri, 4 Jan 2019 15:14:33 +0530
Subject: [PATCH] cpufreq: scpi/scmi: Fix freeing of dynamic OPPs
Commit 1690d8bb91e370ab772062b79bd434ce815c4729 upstream
Since the commit 2a4eb7358aba "OPP: Don't remove dynamic OPPs from
_dev_pm_opp_remove_table()", dynamically created OPP aren't
automatically removed anymore by dev_pm_opp_cpumask_remove_table(). This
affects the scpi and scmi cpufreq drivers which no longer free OPPs on
failures or on invocations of the policy->exit() callback.
Create a generic OPP helper dev_pm_opp_remove_all_dynamic() which can be
called from these drivers instead of dev_pm_opp_cpumask_remove_table().
In dev_pm_opp_remove_all_dynamic(), we need to make sure that the
opp_list isn't getting accessed simultaneously from other parts of the
OPP core while the helper is freeing dynamic OPPs, i.e. we can't drop
the opp_table->lock while traversing through the OPP list. And to
accomplish that, this patch also creates _opp_kref_release_unlocked()
which can be called from this new helper with the opp_table lock already
held.
Cc: 4.20 <stable@vger.kernel.org> # v4.20
Reported-by: Valentin Schneider <valentin.schneider@arm.com>
Fixes: 2a4eb7358aba "OPP: Don't remove dynamic OPPs from _dev_pm_opp_remove_table()"
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
drivers/cpufreq/scmi-cpufreq.c | 4 +--
drivers/cpufreq/scpi-cpufreq.c | 4 +--
drivers/opp/core.c | 63 +++++++++++++++++++++++++++++++---
include/linux/pm_opp.h | 5 +++
4 files changed, 67 insertions(+), 9 deletions(-)
--- a/drivers/cpufreq/scmi-cpufreq.c
+++ b/drivers/cpufreq/scmi-cpufreq.c
@@ -176,7 +176,7 @@ static int scmi_cpufreq_init(struct cpuf
out_free_priv:
kfree(priv);
out_free_opp:
- dev_pm_opp_cpumask_remove_table(policy->cpus);
+ dev_pm_opp_remove_all_dynamic(cpu_dev);
return ret;
}
@@ -188,7 +188,7 @@ static int scmi_cpufreq_exit(struct cpuf
cpufreq_cooling_unregister(priv->cdev);
dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table);
kfree(priv);
- dev_pm_opp_cpumask_remove_table(policy->related_cpus);
+ dev_pm_opp_remove_all_dynamic(priv->cpu_dev);
return 0;
}
--- a/drivers/cpufreq/scpi-cpufreq.c
+++ b/drivers/cpufreq/scpi-cpufreq.c
@@ -177,7 +177,7 @@ out_free_cpufreq_table:
out_free_priv:
kfree(priv);
out_free_opp:
- dev_pm_opp_cpumask_remove_table(policy->cpus);
+ dev_pm_opp_remove_all_dynamic(cpu_dev);
return ret;
}
@@ -190,7 +190,7 @@ static int scpi_cpufreq_exit(struct cpuf
clk_put(priv->clk);
dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table);
kfree(priv);
- dev_pm_opp_cpumask_remove_table(policy->related_cpus);
+ dev_pm_opp_remove_all_dynamic(priv->cpu_dev);
return 0;
}
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -884,11 +884,9 @@ void _opp_free(struct dev_pm_opp *opp)
kfree(opp);
}
-static void _opp_kref_release(struct kref *kref)
+static void _opp_kref_release(struct dev_pm_opp *opp,
+ struct opp_table *opp_table)
{
- struct dev_pm_opp *opp = container_of(kref, struct dev_pm_opp, kref);
- struct opp_table *opp_table = opp->opp_table;
-
/*
* Notify the changes in the availability of the operable
* frequency/voltage list.
@@ -897,7 +895,22 @@ static void _opp_kref_release(struct kre
opp_debug_remove_one(opp);
list_del(&opp->node);
kfree(opp);
+}
+
+static void _opp_kref_release_unlocked(struct kref *kref)
+{
+ struct dev_pm_opp *opp = container_of(kref, struct dev_pm_opp, kref);
+ struct opp_table *opp_table = opp->opp_table;
+
+ _opp_kref_release(opp, opp_table);
+}
+static void _opp_kref_release_locked(struct kref *kref)
+{
+ struct dev_pm_opp *opp = container_of(kref, struct dev_pm_opp, kref);
+ struct opp_table *opp_table = opp->opp_table;
+
+ _opp_kref_release(opp, opp_table);
mutex_unlock(&opp_table->lock);
dev_pm_opp_put_opp_table(opp_table);
}
@@ -909,10 +922,16 @@ void dev_pm_opp_get(struct dev_pm_opp *o
void dev_pm_opp_put(struct dev_pm_opp *opp)
{
- kref_put_mutex(&opp->kref, _opp_kref_release, &opp->opp_table->lock);
+ kref_put_mutex(&opp->kref, _opp_kref_release_locked,
+ &opp->opp_table->lock);
}
EXPORT_SYMBOL_GPL(dev_pm_opp_put);
+static void dev_pm_opp_put_unlocked(struct dev_pm_opp *opp)
+{
+ kref_put(&opp->kref, _opp_kref_release_unlocked);
+}
+
/**
* dev_pm_opp_remove() - Remove an OPP from OPP table
* @dev: device for which we do this operation
@@ -952,6 +971,40 @@ void dev_pm_opp_remove(struct device *de
}
EXPORT_SYMBOL_GPL(dev_pm_opp_remove);
+/**
+ * dev_pm_opp_remove_all_dynamic() - Remove all dynamically created OPPs
+ * @dev: device for which we do this operation
+ *
+ * This function removes all dynamically created OPPs from the opp table.
+ */
+void dev_pm_opp_remove_all_dynamic(struct device *dev)
+{
+ struct opp_table *opp_table;
+ struct dev_pm_opp *opp, *temp;
+ int count = 0;
+
+ opp_table = _find_opp_table(dev);
+ if (IS_ERR(opp_table))
+ return;
+
+ mutex_lock(&opp_table->lock);
+ list_for_each_entry_safe(opp, temp, &opp_table->opp_list, node) {
+ if (opp->dynamic) {
+ dev_pm_opp_put_unlocked(opp);
+ count++;
+ }
+ }
+ mutex_unlock(&opp_table->lock);
+
+ /* Drop the references taken by dev_pm_opp_add() */
+ while (count--)
+ dev_pm_opp_put_opp_table(opp_table);
+
+ /* Drop the reference taken by _find_opp_table() */
+ dev_pm_opp_put_opp_table(opp_table);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_remove_all_dynamic);
+
struct dev_pm_opp *_opp_allocate(struct opp_table *table)
{
struct dev_pm_opp *opp;
--- a/include/linux/pm_opp.h
+++ b/include/linux/pm_opp.h
@@ -107,6 +107,7 @@ void dev_pm_opp_put(struct dev_pm_opp *o
int dev_pm_opp_add(struct device *dev, unsigned long freq,
unsigned long u_volt);
void dev_pm_opp_remove(struct device *dev, unsigned long freq);
+void dev_pm_opp_remove_all_dynamic(struct device *dev);
int dev_pm_opp_enable(struct device *dev, unsigned long freq);
@@ -208,6 +209,10 @@ static inline void dev_pm_opp_remove(str
{
}
+static inline void dev_pm_opp_remove_all_dynamic(struct device *dev)
+{
+}
+
static inline int dev_pm_opp_enable(struct device *dev, unsigned long freq)
{
return 0;
|
