tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Copyright (C) 2016 Red Hat
3 * Author: Rob Clark <robdclark@gmail.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 as published by
7 * the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program. If not, see <http://www.gnu.org/licenses/>.
16 */
17
18#include "msm_drv.h"
19#include "msm_gem.h"
20
21static bool msm_gem_shrinker_lock(struct drm_device *dev, bool *unlock)
22{
23 switch (mutex_trylock_recursive(&dev->struct_mutex)) {
24 case MUTEX_TRYLOCK_FAILED:
25 return false;
26
27 case MUTEX_TRYLOCK_SUCCESS:
28 *unlock = true;
29 return true;
30
31 case MUTEX_TRYLOCK_RECURSIVE:
32 *unlock = false;
33 return true;
34 }
35
36 BUG();
37}
38
39static unsigned long
40msm_gem_shrinker_count(struct shrinker *shrinker, struct shrink_control *sc)
41{
42 struct msm_drm_private *priv =
43 container_of(shrinker, struct msm_drm_private, shrinker);
44 struct drm_device *dev = priv->dev;
45 struct msm_gem_object *msm_obj;
46 unsigned long count = 0;
47 bool unlock;
48
49 if (!msm_gem_shrinker_lock(dev, &unlock))
50 return 0;
51
52 list_for_each_entry(msm_obj, &priv->inactive_list, mm_list) {
53 if (is_purgeable(msm_obj))
54 count += msm_obj->base.size >> PAGE_SHIFT;
55 }
56
57 if (unlock)
58 mutex_unlock(&dev->struct_mutex);
59
60 return count;
61}
62
63static unsigned long
64msm_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc)
65{
66 struct msm_drm_private *priv =
67 container_of(shrinker, struct msm_drm_private, shrinker);
68 struct drm_device *dev = priv->dev;
69 struct msm_gem_object *msm_obj;
70 unsigned long freed = 0;
71 bool unlock;
72
73 if (!msm_gem_shrinker_lock(dev, &unlock))
74 return SHRINK_STOP;
75
76 list_for_each_entry(msm_obj, &priv->inactive_list, mm_list) {
77 if (freed >= sc->nr_to_scan)
78 break;
79 if (is_purgeable(msm_obj)) {
80 msm_gem_purge(&msm_obj->base);
81 freed += msm_obj->base.size >> PAGE_SHIFT;
82 }
83 }
84
85 if (unlock)
86 mutex_unlock(&dev->struct_mutex);
87
88 if (freed > 0)
89 pr_info_ratelimited("Purging %lu bytes\n", freed << PAGE_SHIFT);
90
91 return freed;
92}
93
94static int
95msm_gem_shrinker_vmap(struct notifier_block *nb, unsigned long event, void *ptr)
96{
97 struct msm_drm_private *priv =
98 container_of(nb, struct msm_drm_private, vmap_notifier);
99 struct drm_device *dev = priv->dev;
100 struct msm_gem_object *msm_obj;
101 unsigned unmapped = 0;
102 bool unlock;
103
104 if (!msm_gem_shrinker_lock(dev, &unlock))
105 return NOTIFY_DONE;
106
107 list_for_each_entry(msm_obj, &priv->inactive_list, mm_list) {
108 if (is_vunmapable(msm_obj)) {
109 msm_gem_vunmap(&msm_obj->base);
110 /* since we don't know any better, lets bail after a few
111 * and if necessary the shrinker will be invoked again.
112 * Seems better than unmapping *everything*
113 */
114 if (++unmapped >= 15)
115 break;
116 }
117 }
118
119 if (unlock)
120 mutex_unlock(&dev->struct_mutex);
121
122 *(unsigned long *)ptr += unmapped;
123
124 if (unmapped > 0)
125 pr_info_ratelimited("Purging %u vmaps\n", unmapped);
126
127 return NOTIFY_DONE;
128}
129
130/**
131 * msm_gem_shrinker_init - Initialize msm shrinker
132 * @dev_priv: msm device
133 *
134 * This function registers and sets up the msm shrinker.
135 */
136void msm_gem_shrinker_init(struct drm_device *dev)
137{
138 struct msm_drm_private *priv = dev->dev_private;
139 priv->shrinker.count_objects = msm_gem_shrinker_count;
140 priv->shrinker.scan_objects = msm_gem_shrinker_scan;
141 priv->shrinker.seeks = DEFAULT_SEEKS;
142 WARN_ON(register_shrinker(&priv->shrinker));
143
144 priv->vmap_notifier.notifier_call = msm_gem_shrinker_vmap;
145 WARN_ON(register_vmap_purge_notifier(&priv->vmap_notifier));
146}
147
148/**
149 * msm_gem_shrinker_cleanup - Clean up msm shrinker
150 * @dev_priv: msm device
151 *
152 * This function unregisters the msm shrinker.
153 */
154void msm_gem_shrinker_cleanup(struct drm_device *dev)
155{
156 struct msm_drm_private *priv = dev->dev_private;
157
158 if (priv->shrinker.nr_deferred) {
159 WARN_ON(unregister_vmap_purge_notifier(&priv->vmap_notifier));
160 unregister_shrinker(&priv->shrinker);
161 }
162}