62 lines
1.3 KiB
C
62 lines
1.3 KiB
C
/*
|
|
* SPDX-License-Identifier: MIT
|
|
*
|
|
* Copyright © 2019 Intel Corporation
|
|
*/
|
|
|
|
#include "intel_drv.h"
|
|
#include "intel_wakeref.h"
|
|
|
|
int __intel_wakeref_get_first(struct drm_i915_private *i915,
|
|
struct intel_wakeref *wf,
|
|
int (*fn)(struct intel_wakeref *wf))
|
|
{
|
|
/*
|
|
* Treat get/put as different subclasses, as we may need to run
|
|
* the put callback from under the shrinker and do not want to
|
|
* cross-contanimate that callback with any extra work performed
|
|
* upon acquiring the wakeref.
|
|
*/
|
|
mutex_lock_nested(&wf->mutex, SINGLE_DEPTH_NESTING);
|
|
if (!atomic_read(&wf->count)) {
|
|
int err;
|
|
|
|
wf->wakeref = intel_runtime_pm_get(i915);
|
|
|
|
err = fn(wf);
|
|
if (unlikely(err)) {
|
|
intel_runtime_pm_put(i915, wf->wakeref);
|
|
mutex_unlock(&wf->mutex);
|
|
return err;
|
|
}
|
|
|
|
smp_mb__before_atomic(); /* release wf->count */
|
|
}
|
|
atomic_inc(&wf->count);
|
|
mutex_unlock(&wf->mutex);
|
|
|
|
return 0;
|
|
}
|
|
|
|
int __intel_wakeref_put_last(struct drm_i915_private *i915,
|
|
struct intel_wakeref *wf,
|
|
int (*fn)(struct intel_wakeref *wf))
|
|
{
|
|
int err;
|
|
|
|
err = fn(wf);
|
|
if (likely(!err))
|
|
intel_runtime_pm_put(i915, wf->wakeref);
|
|
else
|
|
atomic_inc(&wf->count);
|
|
mutex_unlock(&wf->mutex);
|
|
|
|
return err;
|
|
}
|
|
|
|
void __intel_wakeref_init(struct intel_wakeref *wf, struct lock_class_key *key)
|
|
{
|
|
__mutex_init(&wf->mutex, "wakeref", key);
|
|
atomic_set(&wf->count, 0);
|
|
}
|