diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2016-10-07 17:43:51 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2016-11-15 14:19:55 +0100 |
| commit | 0f5225b024d4bffd682aab008c35862e8fdc1865 (patch) | |
| tree | a5202d5cdb071b3060975c4bd4c1c3f56c792edc /drivers/gpu/drm/msm/msm_gem_shrinker.c | |
| parent | 83f06168ef15da5dc735c7ea14fae67609ed9538 (diff) | |
locking/mutex, drm: Introduce mutex_trylock_recursive()
By popular DRM demand, introduce mutex_trylock_recursive() to fix up the
two GEM users.
Without this it is very easy for these drivers to get stuck in
low-memory situations and trigger OOM. Work is in progress to remove the
need for this in at least i915.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Ding Tianhong <dingtianhong@huawei.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Jason Low <jason.low2@hpe.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Terry Rudd <terry.rudd@hpe.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Will Deacon <Will.Deacon@arm.com>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'drivers/gpu/drm/msm/msm_gem_shrinker.c')
| -rw-r--r-- | drivers/gpu/drm/msm/msm_gem_shrinker.c | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/drivers/gpu/drm/msm/msm_gem_shrinker.c b/drivers/gpu/drm/msm/msm_gem_shrinker.c index 6d2e885bd58e..b77bca75bb5f 100644 --- a/drivers/gpu/drm/msm/msm_gem_shrinker.c +++ b/drivers/gpu/drm/msm/msm_gem_shrinker.c @@ -20,13 +20,21 @@ static bool msm_gem_shrinker_lock(struct drm_device *dev, bool *unlock) { - if (!mutex_trylock(&dev->struct_mutex)) + switch (mutex_trylock_recursive(&dev->struct_mutex)) { + case MUTEX_TRYLOCK_FAILED: return false; - *unlock = true; - return true; -} + 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) |