blob: b72d8e6cd51d76b7f3824c6586d95e88f3b39f62 [file] [log] [blame]
/*
* Copyright (C) 2016 Red Hat
* Author: Rob Clark <robdclark@gmail.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "msm_drv.h"
#include "msm_gem.h"
static bool msm_gem_shrinker_lock(struct drm_device *dev, bool *unlock)
{
/* NOTE: we are *closer* to being able to get rid of
* mutex_trylock_recursive().. the msm_gem code itself does
* not need struct_mutex, although codepaths that can trigger
* shrinker are still called in code-paths that hold the
* struct_mutex.
*
* Also, msm_obj->madv is protected by struct_mutex.
*
* The next step is probably split out a seperate lock for
* protecting inactive_list, so that shrinker does not need
* struct_mutex.
*/
switch (mutex_trylock_recursive(&dev->struct_mutex)) {
case MUTEX_TRYLOCK_FAILED:
return false;
case MUTEX_TRYLOCK_SUCCESS:
*unlock = true;
return true;
case MUTEX_TRYLOCK_RECURSIVE:
*unlock = false;
return true;
}
BUG();
}
static unsigned long
msm_gem_shrinker_count(struct shrinker *shrinker, struct shrink_control *sc)
{
struct msm_drm_private *priv =
container_of(shrinker, struct msm_drm_private, shrinker);
struct drm_device *dev = priv->dev;
struct msm_gem_object *msm_obj;
unsigned long count = 0;
bool unlock;
if (!msm_gem_shrinker_lock(dev, &unlock))
return 0;
list_for_each_entry(msm_obj, &priv->inactive_list, mm_list) {
if (is_purgeable(msm_obj))
count += msm_obj->base.size >> PAGE_SHIFT;
}
if (unlock)
mutex_unlock(&dev->struct_mutex);
return count;
}
static unsigned long
msm_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc)
{
struct msm_drm_private *priv =
container_of(shrinker, struct msm_drm_private, shrinker);
struct drm_device *dev = priv->dev;
struct msm_gem_object *msm_obj;
unsigned long freed = 0;
bool unlock;
if (!msm_gem_shrinker_lock(dev, &unlock))
return SHRINK_STOP;
list_for_each_entry(msm_obj, &priv->inactive_list, mm_list) {
if (freed >= sc->nr_to_scan)
break;
if (is_purgeable(msm_obj)) {
msm_gem_purge(&msm_obj->base, OBJ_LOCK_SHRINKER);
freed += msm_obj->base.size >> PAGE_SHIFT;
}
}
if (unlock)
mutex_unlock(&dev->struct_mutex);
if (freed > 0)
pr_info_ratelimited("Purging %lu bytes\n", freed << PAGE_SHIFT);
return freed;
}
static int
msm_gem_shrinker_vmap(struct notifier_block *nb, unsigned long event, void *ptr)
{
struct msm_drm_private *priv =
container_of(nb, struct msm_drm_private, vmap_notifier);
struct drm_device *dev = priv->dev;
struct msm_gem_object *msm_obj;
unsigned unmapped = 0;
bool unlock;
if (!msm_gem_shrinker_lock(dev, &unlock))
return NOTIFY_DONE;
list_for_each_entry(msm_obj, &priv->inactive_list, mm_list) {
if (is_vunmapable(msm_obj)) {
msm_gem_vunmap(&msm_obj->base, OBJ_LOCK_SHRINKER);
/* since we don't know any better, lets bail after a few
* and if necessary the shrinker will be invoked again.
* Seems better than unmapping *everything*
*/
if (++unmapped >= 15)
break;
}
}
if (unlock)
mutex_unlock(&dev->struct_mutex);
*(unsigned long *)ptr += unmapped;
if (unmapped > 0)
pr_info_ratelimited("Purging %u vmaps\n", unmapped);
return NOTIFY_DONE;
}
/**
* msm_gem_shrinker_init - Initialize msm shrinker
* @dev_priv: msm device
*
* This function registers and sets up the msm shrinker.
*/
void msm_gem_shrinker_init(struct drm_device *dev)
{
struct msm_drm_private *priv = dev->dev_private;
priv->shrinker.count_objects = msm_gem_shrinker_count;
priv->shrinker.scan_objects = msm_gem_shrinker_scan;
priv->shrinker.seeks = DEFAULT_SEEKS;
WARN_ON(register_shrinker(&priv->shrinker));
priv->vmap_notifier.notifier_call = msm_gem_shrinker_vmap;
WARN_ON(register_vmap_purge_notifier(&priv->vmap_notifier));
}
/**
* msm_gem_shrinker_cleanup - Clean up msm shrinker
* @dev_priv: msm device
*
* This function unregisters the msm shrinker.
*/
void msm_gem_shrinker_cleanup(struct drm_device *dev)
{
struct msm_drm_private *priv = dev->dev_private;
if (priv->shrinker.nr_deferred) {
WARN_ON(unregister_vmap_purge_notifier(&priv->vmap_notifier));
unregister_shrinker(&priv->shrinker);
}
}