[PATCH 10/15] drm/msm/gem: Remove active refcnt

From: Rob Clark
Date: Sat Jun 25 2022 - 18:55:46 EST


From: Rob Clark <robdclark@xxxxxxxxxxxx>

At this point the pinned refcnt is sufficient, and the shrinker is
already prepared to encounter objects which are still active according
to fences attached to the resv.

Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>
---
drivers/gpu/drm/msm/msm_gem.c | 45 ++--------------------------
drivers/gpu/drm/msm/msm_gem.h | 14 ++-------
drivers/gpu/drm/msm/msm_gem_submit.c | 22 ++------------
3 files changed, 8 insertions(+), 73 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
index 407b18a24dc4..209438744bab 100644
--- a/drivers/gpu/drm/msm/msm_gem.c
+++ b/drivers/gpu/drm/msm/msm_gem.c
@@ -734,8 +734,7 @@ int msm_gem_madvise(struct drm_gem_object *obj, unsigned madv)
/* If the obj is inactive, we might need to move it
* between inactive lists
*/
- if (msm_obj->active_count == 0)
- update_lru(obj);
+ update_lru(obj);

msm_gem_unlock(obj);

@@ -788,7 +787,6 @@ void msm_gem_evict(struct drm_gem_object *obj)
GEM_WARN_ON(!msm_gem_is_locked(obj));
GEM_WARN_ON(is_unevictable(msm_obj));
GEM_WARN_ON(!msm_obj->evictable);
- GEM_WARN_ON(msm_obj->active_count);

/* Get rid of any iommu mapping(s): */
put_iova_spaces(obj, false);
@@ -813,37 +811,6 @@ void msm_gem_vunmap(struct drm_gem_object *obj)
msm_obj->vaddr = NULL;
}

-void msm_gem_active_get(struct drm_gem_object *obj, struct msm_gpu *gpu)
-{
- struct msm_gem_object *msm_obj = to_msm_bo(obj);
- struct msm_drm_private *priv = obj->dev->dev_private;
-
- might_sleep();
- GEM_WARN_ON(!msm_gem_is_locked(obj));
- GEM_WARN_ON(msm_obj->madv != MSM_MADV_WILLNEED);
- GEM_WARN_ON(msm_obj->dontneed);
-
- if (msm_obj->active_count++ == 0) {
- mutex_lock(&priv->mm_lock);
- if (msm_obj->evictable)
- mark_unevictable(msm_obj);
- list_move_tail(&msm_obj->mm_list, &gpu->active_list);
- mutex_unlock(&priv->mm_lock);
- }
-}
-
-void msm_gem_active_put(struct drm_gem_object *obj)
-{
- struct msm_gem_object *msm_obj = to_msm_bo(obj);
-
- might_sleep();
- GEM_WARN_ON(!msm_gem_is_locked(obj));
-
- if (--msm_obj->active_count == 0) {
- update_lru(obj);
- }
-}
-
static void update_lru(struct drm_gem_object *obj)
{
struct msm_drm_private *priv = obj->dev->dev_private;
@@ -851,9 +818,6 @@ static void update_lru(struct drm_gem_object *obj)

GEM_WARN_ON(!msm_gem_is_locked(&msm_obj->base));

- if (msm_obj->active_count != 0)
- return;
-
mutex_lock(&priv->mm_lock);

if (msm_obj->dontneed)
@@ -926,7 +890,7 @@ void msm_gem_describe(struct drm_gem_object *obj, struct seq_file *m,
stats->all.count++;
stats->all.size += obj->size;

- if (is_active(msm_obj)) {
+ if (msm_gem_active(obj)) {
stats->active.count++;
stats->active.size += obj->size;
}
@@ -954,7 +918,7 @@ void msm_gem_describe(struct drm_gem_object *obj, struct seq_file *m,
}

seq_printf(m, "%08x: %c %2d (%2d) %08llx %p",
- msm_obj->flags, is_active(msm_obj) ? 'A' : 'I',
+ msm_obj->flags, msm_gem_active(obj) ? 'A' : 'I',
obj->name, kref_read(&obj->refcount),
off, msm_obj->vaddr);

@@ -1037,9 +1001,6 @@ static void msm_gem_free_object(struct drm_gem_object *obj)
list_del(&msm_obj->mm_list);
mutex_unlock(&priv->mm_lock);

- /* object should not be on active list: */
- GEM_WARN_ON(is_active(msm_obj));
-
put_iova_spaces(obj, true);

if (obj->import_attach) {
diff --git a/drivers/gpu/drm/msm/msm_gem.h b/drivers/gpu/drm/msm/msm_gem.h
index 6fe521ccda45..420ba49bf21a 100644
--- a/drivers/gpu/drm/msm/msm_gem.h
+++ b/drivers/gpu/drm/msm/msm_gem.h
@@ -138,7 +138,6 @@ struct msm_gem_object {

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

- int active_count;
int pin_count;
};
#define to_msm_bo(x) container_of(x, struct msm_gem_object, base)
@@ -171,8 +170,6 @@ void *msm_gem_get_vaddr_active(struct drm_gem_object *obj);
void msm_gem_put_vaddr_locked(struct drm_gem_object *obj);
void msm_gem_put_vaddr(struct drm_gem_object *obj);
int msm_gem_madvise(struct drm_gem_object *obj, unsigned madv);
-void msm_gem_active_get(struct drm_gem_object *obj, struct msm_gpu *gpu);
-void msm_gem_active_put(struct drm_gem_object *obj);
bool msm_gem_active(struct drm_gem_object *obj);
int msm_gem_cpu_prep(struct drm_gem_object *obj, uint32_t op, ktime_t *timeout);
int msm_gem_cpu_fini(struct drm_gem_object *obj);
@@ -245,12 +242,6 @@ msm_gem_is_locked(struct drm_gem_object *obj)
return dma_resv_is_locked(obj->resv) || (kref_read(&obj->refcount) == 0);
}

-static inline bool is_active(struct msm_gem_object *msm_obj)
-{
- GEM_WARN_ON(!msm_gem_is_locked(&msm_obj->base));
- return msm_obj->active_count;
-}
-
/* imported/exported objects are not purgeable: */
static inline bool is_unpurgeable(struct msm_gem_object *msm_obj)
{
@@ -391,9 +382,8 @@ struct msm_gem_submit {
/* make sure these don't conflict w/ MSM_SUBMIT_BO_x */
#define BO_VALID 0x8000 /* is current addr in cmdstream correct/valid? */
#define BO_LOCKED 0x4000 /* obj lock is held */
-#define BO_ACTIVE 0x2000 /* active refcnt is held */
-#define BO_OBJ_PINNED 0x1000 /* obj (pages) is pinned and on active list */
-#define BO_VMA_PINNED 0x0800 /* vma (virtual address) is pinned */
+#define BO_OBJ_PINNED 0x2000 /* obj (pages) is pinned and on active list */
+#define BO_VMA_PINNED 0x1000 /* vma (virtual address) is pinned */
uint32_t flags;
union {
struct msm_gem_object *obj;
diff --git a/drivers/gpu/drm/msm/msm_gem_submit.c b/drivers/gpu/drm/msm/msm_gem_submit.c
index 16c662808522..adf358fb8e9d 100644
--- a/drivers/gpu/drm/msm/msm_gem_submit.c
+++ b/drivers/gpu/drm/msm/msm_gem_submit.c
@@ -243,17 +243,13 @@ static void submit_cleanup_bo(struct msm_gem_submit *submit, int i,
if (flags & BO_OBJ_PINNED)
msm_gem_unpin_locked(obj);

- if (flags & BO_ACTIVE)
- msm_gem_active_put(obj);
-
if (flags & BO_LOCKED)
dma_resv_unlock(obj->resv);
}

static void submit_unlock_unpin_bo(struct msm_gem_submit *submit, int i)
{
- unsigned cleanup_flags = BO_VMA_PINNED | BO_OBJ_PINNED |
- BO_ACTIVE | BO_LOCKED;
+ unsigned cleanup_flags = BO_VMA_PINNED | BO_OBJ_PINNED | BO_LOCKED;
submit_cleanup_bo(submit, i, cleanup_flags);

if (!(submit->bos[i].flags & BO_VALID))
@@ -358,18 +354,6 @@ static int submit_pin_objects(struct msm_gem_submit *submit)

submit->valid = true;

- /*
- * Increment active_count first, so if under memory pressure, we
- * don't inadvertently evict a bo needed by the submit in order
- * to pin an earlier bo in the same submit.
- */
- for (i = 0; i < submit->nr_bos; i++) {
- struct drm_gem_object *obj = &submit->bos[i].obj->base;
-
- msm_gem_active_get(obj, submit->gpu);
- submit->bos[i].flags |= BO_ACTIVE;
- }
-
for (i = 0; i < submit->nr_bos; i++) {
struct drm_gem_object *obj = &submit->bos[i].obj->base;
struct msm_gem_vma *vma;
@@ -521,7 +505,7 @@ static void submit_cleanup(struct msm_gem_submit *submit, bool error)
unsigned i;

if (error)
- cleanup_flags |= BO_VMA_PINNED | BO_OBJ_PINNED | BO_ACTIVE;
+ cleanup_flags |= BO_VMA_PINNED | BO_OBJ_PINNED;

for (i = 0; i < submit->nr_bos; i++) {
struct msm_gem_object *msm_obj = submit->bos[i].obj;
@@ -540,7 +524,7 @@ void msm_submit_retire(struct msm_gem_submit *submit)

msm_gem_lock(obj);
/* Note, VMA already fence-unpinned before submit: */
- submit_cleanup_bo(submit, i, BO_OBJ_PINNED | BO_ACTIVE);
+ submit_cleanup_bo(submit, i, BO_OBJ_PINNED);
msm_gem_unlock(obj);
drm_gem_object_put(obj);
}
--
2.36.1