[PATCH v3 09/23] drm/msm/gem: Switch over to obj->resv for locking

Rob Clark
2020-10-19T20:47:08Z

This also converts the special msm_gem_get_vaddr_active() to expect the
lock to already be held. There are two call-sites for this, one already
has the lock held, so it is more straightforward to just open-code the
locking for the other caller.

Signed-off-by: Rob Clark <robdclark@chromium.org>
---
drivers/gpu/drm/msm/msm_gem.c | 12 ++----------
drivers/gpu/drm/msm/msm_gem.h | 16 +++++-----------
drivers/gpu/drm/msm/msm_gem_submit.c | 8 ++++----
drivers/gpu/drm/msm/msm_gpu.c | 14 ++++++++++++--
drivers/gpu/drm/msm/msm_rd.c | 2 +-
5 files changed, 24 insertions(+), 28 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
index 1195847714ba..6abcf9fe480d 100644
--- a/drivers/gpu/drm/msm/msm_gem.c
+++ b/drivers/gpu/drm/msm/msm_gem.c
@@ -644,13 +644,7 @@ void *msm_gem_get_vaddr(struct drm_gem_object *obj)
*/
void *msm_gem_get_vaddr_active(struct drm_gem_object *obj)
{
- void *ret;
-
- msm_gem_lock(obj);
- ret = get_vaddr(obj, __MSM_MADV_PURGED);
- msm_gem_unlock(obj);
-
- return ret;
+ return get_vaddr(obj, __MSM_MADV_PURGED);
}

void msm_gem_put_vaddr_locked(struct drm_gem_object *obj)
@@ -976,9 +970,9 @@ static void free_object(struct msm_gem_object *msm_obj)
put_pages(obj);
}

+ msm_gem_unlock(obj);
drm_gem_object_release(obj);

- msm_gem_unlock(obj);
kfree(msm_obj);
}

@@ -1050,8 +1044,6 @@ static int msm_gem_new_impl(struct drm_device *dev,
if (!msm_obj)
return -ENOMEM;

- mutex_init(&msm_obj->lock);
-
msm_obj->flags = flags;
msm_obj->madv = MSM_MADV_WILLNEED;

diff --git a/drivers/gpu/drm/msm/msm_gem.h b/drivers/gpu/drm/msm/msm_gem.h
index 0b7dda312992..f0608d96ef03 100644
--- a/drivers/gpu/drm/msm/msm_gem.h
+++ b/drivers/gpu/drm/msm/msm_gem.h
@@ -85,7 +85,6 @@ struct msm_gem_object {
* an IOMMU. Also used for stolen/splashscreen buffer.
*/
struct drm_mm_node *vram_node;
- struct mutex lock; /* Protects resources associated with bo */

char name[32]; /* Identifier to print for the debugfs files */

@@ -158,36 +157,31 @@ void msm_gem_describe_objects(struct list_head *list, struct seq_file *m);
static inline void
msm_gem_lock(struct drm_gem_object *obj)
{
- struct msm_gem_object *msm_obj = to_msm_bo(obj);
- mutex_lock(&msm_obj->lock);
+ dma_resv_lock(obj->resv, NULL);
}

static inline bool __must_check
msm_gem_trylock(struct drm_gem_object *obj)
{
- struct msm_gem_object *msm_obj = to_msm_bo(obj);
- return mutex_trylock_recursive(&msm_obj->lock) == MUTEX_TRYLOCK_SUCCESS;
+ return dma_resv_trylock(obj->resv);
}

static inline int
msm_gem_lock_interruptible(struct drm_gem_object *obj)
{
- struct msm_gem_object *msm_obj = to_msm_bo(obj);
- return mutex_lock_interruptible(&msm_obj->lock);
+ return dma_resv_lock_interruptible(obj->resv, NULL);
}

static inline void
msm_gem_unlock(struct drm_gem_object *obj)
{
- struct msm_gem_object *msm_obj = to_msm_bo(obj);
- mutex_unlock(&msm_obj->lock);
+ dma_resv_unlock(obj->resv);
}

static inline bool
msm_gem_is_locked(struct drm_gem_object *obj)
{
- struct msm_gem_object *msm_obj = to_msm_bo(obj);
- return mutex_is_locked(&msm_obj->lock);
+ return dma_resv_is_locked(obj->resv);
}

static inline bool is_active(struct msm_gem_object *msm_obj)
diff --git a/drivers/gpu/drm/msm/msm_gem_submit.c b/drivers/gpu/drm/msm/msm_gem_submit.c
index a9422d043bfe..50ecc8455197 100644
--- a/drivers/gpu/drm/msm/msm_gem_submit.c
+++ b/drivers/gpu/drm/msm/msm_gem_submit.c
@@ -215,7 +215,7 @@ static void submit_unlock_unpin_bo(struct msm_gem_submit *submit,
struct msm_gem_object *msm_obj = submit->bos[i].obj;

if (submit->bos[i].flags & BO_PINNED)
- msm_gem_unpin_iova(&msm_obj->base, submit->aspace);
+ msm_gem_unpin_iova_locked(&msm_obj->base, submit->aspace);

if (submit->bos[i].flags & BO_LOCKED)
dma_resv_unlock(msm_obj->base.resv);
@@ -318,7 +318,7 @@ static int submit_pin_objects(struct msm_gem_submit *submit)
uint64_t iova;

/* if locking succeeded, pin bo: */
- ret = msm_gem_get_and_pin_iova(&msm_obj->base,
+ ret = msm_gem_get_and_pin_iova_locked(&msm_obj->base,
submit->aspace, &iova);

if (ret)
@@ -377,7 +377,7 @@ static int submit_reloc(struct msm_gem_submit *submit, struct msm_gem_object *ob
/* For now, just map the entire thing. Eventually we probably
* to do it page-by-page, w/ kmap() if not vmap()d..
*/
- ptr = msm_gem_get_vaddr(&obj->base);
+ ptr = msm_gem_get_vaddr_locked(&obj->base);

if (IS_ERR(ptr)) {
ret = PTR_ERR(ptr);
@@ -428,7 +428,7 @@ static int submit_reloc(struct msm_gem_submit *submit, struct msm_gem_object *ob
}

out:
- msm_gem_put_vaddr(&obj->base);
+ msm_gem_put_vaddr_locked(&obj->base);

return ret;
}
diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
index 55d16489d0f3..015f6b884e2e 100644
--- a/drivers/gpu/drm/msm/msm_gpu.c
+++ b/drivers/gpu/drm/msm/msm_gpu.c
@@ -326,7 +326,9 @@ static void msm_gpu_crashstate_get_bo(struct msm_gpu_state *state,
if (!state_bo->data)
goto out;

+ msm_gem_lock(&obj->base);
ptr = msm_gem_get_vaddr_active(&obj->base);
+ msm_gem_unlock(&obj->base);
if (IS_ERR(ptr)) {
kvfree(state_bo->data);
state_bo->data = NULL;
@@ -470,14 +472,22 @@ static void recover_worker(struct work_struct *work)
put_task_struct(task);
}

+ /* msm_rd_dump_submit() needs bo locked to dump: */
+ for (i = 0; i < submit->nr_bos; i++)
+ msm_gem_lock(&submit->bos[i].obj->base);
+
if (comm && cmd) {
DRM_DEV_ERROR(dev->dev, "%s: offending task: %s (%s)\n",
gpu->name, comm, cmd);

msm_rd_dump_submit(priv->hangrd, submit,
"offending task: %s (%s)", comm, cmd);
- } else
+ } else {
msm_rd_dump_submit(priv->hangrd, submit, NULL);
+ }
+
+ for (i = 0; i < submit->nr_bos; i++)
+ msm_gem_unlock(&submit->bos[i].obj->base);
}

/* Record the crash state */
@@ -784,7 +794,7 @@ void msm_gpu_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)

/* submit takes a reference to the bo and iova until retired: */
drm_gem_object_get(&msm_obj->base);
- msm_gem_get_and_pin_iova(&msm_obj->base, submit->aspace, &iova);
+ msm_gem_get_and_pin_iova_locked(&msm_obj->base, submit->aspace, &iova);

if (submit->bos[i].flags & MSM_SUBMIT_BO_WRITE)
dma_resv_add_excl_fence(drm_obj->resv, submit->fence);
diff --git a/drivers/gpu/drm/msm/msm_rd.c b/drivers/gpu/drm/msm/msm_rd.c
index fea30e7aa9e8..659e5cc4b40a 100644
--- a/drivers/gpu/drm/msm/msm_rd.c
+++ b/drivers/gpu/drm/msm/msm_rd.c
@@ -333,7 +333,7 @@ static void snapshot_buf(struct msm_rd_state *rd,

rd_write_section(rd, RD_BUFFER_CONTENTS, buf, size);

- msm_gem_put_vaddr(&obj->base);
+ msm_gem_put_vaddr_locked(&obj->base);
}

/* called under struct_mutex */
--
2.26.2