diff options
| author | Chris Wilson <chris@chris-wilson.co.uk> | 2019-11-20 12:54:33 +0000 |
|---|---|---|
| committer | Chris Wilson <chris@chris-wilson.co.uk> | 2019-11-20 15:59:23 +0000 |
| commit | 07779a76ee1f93f930cf697b22be73d16e14f50c (patch) | |
| tree | 06ccd469c0fa100c2dda52a0ad99c0bce5ebe376 /drivers/gpu/drm/i915/intel_wakeref.c | |
| parent | 8a126392b7d7b95cffbf164b0f85974df7d70852 (diff) | |
drm/i915: Mark up the calling context for intel_wakeref_put()
Previously, we assumed we could use mutex_trylock() within an atomic
context, falling back to a worker if contended. However, such trickery
is illegal inside interrupt context, and so we need to always use a
worker under such circumstances. As we normally are in process context,
we can typically use a plain mutex, and only defer to a work when we
know we are being called from an interrupt path.
Fixes: 51fbd8de87dc ("drm/i915/pmu: Atomically acquire the gt_pm wakeref")
References: a0855d24fc22d ("locking/mutex: Complain upon mutex API misuse in IRQ contexts")
References: https://bugs.freedesktop.org/show_bug.cgi?id=111626
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191120125433.3767149-1-chris@chris-wilson.co.uk
Diffstat (limited to 'drivers/gpu/drm/i915/intel_wakeref.c')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_wakeref.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/gpu/drm/i915/intel_wakeref.c b/drivers/gpu/drm/i915/intel_wakeref.c index ad26d7f4ca3d..59aa1b6f1827 100644 --- a/drivers/gpu/drm/i915/intel_wakeref.c +++ b/drivers/gpu/drm/i915/intel_wakeref.c @@ -54,7 +54,8 @@ int __intel_wakeref_get_first(struct intel_wakeref *wf) static void ____intel_wakeref_put_last(struct intel_wakeref *wf) { - if (!atomic_dec_and_test(&wf->count)) + INTEL_WAKEREF_BUG_ON(atomic_read(&wf->count) <= 0); + if (unlikely(!atomic_dec_and_test(&wf->count))) goto unlock; /* ops->put() must reschedule its own release on error/deferral */ @@ -67,13 +68,12 @@ unlock: mutex_unlock(&wf->mutex); } -void __intel_wakeref_put_last(struct intel_wakeref *wf) +void __intel_wakeref_put_last(struct intel_wakeref *wf, unsigned long flags) { INTEL_WAKEREF_BUG_ON(work_pending(&wf->work)); /* Assume we are not in process context and so cannot sleep. */ - if (wf->ops->flags & INTEL_WAKEREF_PUT_ASYNC || - !mutex_trylock(&wf->mutex)) { + if (flags & INTEL_WAKEREF_PUT_ASYNC || !mutex_trylock(&wf->mutex)) { schedule_work(&wf->work); return; } |