If no reservation ticket is given to the execbuf reservation utilities,
try reservation with non-blocking semantics.
This is intended for eviction paths that use the execbuf reservation
utilities for convenience rather than for deadlock avoidance.
Signed-off-by: Thomas Hellstrom <thellstrom at vmware.com>
---
drivers/gpu/drm/ttm/ttm_execbuf_util.c | 32 +++++++++++++++++++-------------
include/drm/ttm/ttm_execbuf_util.h | 3 ++-
2 files changed, 21 insertions(+), 14 deletions(-)
diff --git a/drivers/gpu/drm/ttm/ttm_execbuf_util.c
b/drivers/gpu/drm/ttm/ttm_execbuf_util.c
index 6c91178..479e941 100644
--- a/drivers/gpu/drm/ttm/ttm_execbuf_util.c
+++ b/drivers/gpu/drm/ttm/ttm_execbuf_util.c
@@ -32,8 +32,7 @@
#include <linux/sched.h>
#include <linux/module.h>
-static void ttm_eu_backoff_reservation_locked(struct list_head *list,
- struct ww_acquire_ctx *ticket)
+static void ttm_eu_backoff_reservation_locked(struct list_head *list)
{
struct ttm_validate_buffer *entry;
@@ -93,8 +92,9 @@ void ttm_eu_backoff_reservation(struct ww_acquire_ctx *ticket,
entry = list_first_entry(list, struct ttm_validate_buffer, head);
glob = entry->bo->glob;
spin_lock(&glob->lru_lock);
- ttm_eu_backoff_reservation_locked(list, ticket);
- ww_acquire_fini(ticket);
+ ttm_eu_backoff_reservation_locked(list);
+ if (ticket)
+ ww_acquire_fini(ticket);
spin_unlock(&glob->lru_lock);
}
EXPORT_SYMBOL(ttm_eu_backoff_reservation);
@@ -130,7 +130,8 @@ int ttm_eu_reserve_buffers(struct ww_acquire_ctx *ticket,
entry = list_first_entry(list, struct ttm_validate_buffer, head);
glob = entry->bo->glob;
- ww_acquire_init(ticket, &reservation_ww_class);
+ if (ticket)
+ ww_acquire_init(ticket, &reservation_ww_class);
retry:
list_for_each_entry(entry, list, head) {
struct ttm_buffer_object *bo = entry->bo;
@@ -139,16 +140,17 @@ retry:
if (entry->reserved)
continue;
-
- ret = ttm_bo_reserve_nolru(bo, true, false, true, ticket);
+ ret = ttm_bo_reserve_nolru(bo, true, (ticket == NULL), true,
+ ticket);
if (ret == -EDEADLK) {
/* uh oh, we lost out, drop every reservation and try
* to only reserve this buffer, then start over if
* this succeeds.
*/
+ BUG_ON(ticket == NULL);
spin_lock(&glob->lru_lock);
- ttm_eu_backoff_reservation_locked(list, ticket);
+ ttm_eu_backoff_reservation_locked(list);
spin_unlock(&glob->lru_lock);
ttm_eu_list_ref_sub(list);
ret = ww_mutex_lock_slow_interruptible(&bo->resv->lock,
@@ -175,7 +177,8 @@ retry:
}
}
- ww_acquire_done(ticket);
+ if (ticket)
+ ww_acquire_done(ticket);
spin_lock(&glob->lru_lock);
ttm_eu_del_from_lru_locked(list);
spin_unlock(&glob->lru_lock);
@@ -184,12 +187,14 @@ retry:
err:
spin_lock(&glob->lru_lock);
- ttm_eu_backoff_reservation_locked(list, ticket);
+ ttm_eu_backoff_reservation_locked(list);
spin_unlock(&glob->lru_lock);
ttm_eu_list_ref_sub(list);
err_fini:
- ww_acquire_done(ticket);
- ww_acquire_fini(ticket);
+ if (ticket) {
+ ww_acquire_done(ticket);
+ ww_acquire_fini(ticket);
+ }
return ret;
}
EXPORT_SYMBOL(ttm_eu_reserve_buffers);
@@ -224,7 +229,8 @@ void ttm_eu_fence_buffer_objects(struct ww_acquire_ctx
*ticket,
}
spin_unlock(&bdev->fence_lock);
spin_unlock(&glob->lru_lock);
- ww_acquire_fini(ticket);
+ if (ticket)
+ ww_acquire_fini(ticket);
list_for_each_entry(entry, list, head) {
if (entry->old_sync_obj)
diff --git a/include/drm/ttm/ttm_execbuf_util.h
b/include/drm/ttm/ttm_execbuf_util.h
index ec8a1d3..16db7d0 100644
--- a/include/drm/ttm/ttm_execbuf_util.h
+++ b/include/drm/ttm/ttm_execbuf_util.h
@@ -70,7 +70,8 @@ extern void ttm_eu_backoff_reservation(struct ww_acquire_ctx
*ticket,
/**
* function ttm_eu_reserve_buffers
*
- * @ticket: [out] ww_acquire_ctx returned by call.
+ * @ticket: [out] ww_acquire_ctx filled in by call, or NULL if only
+ * non-blocking reserves should be tried.
* @list: thread private list of ttm_validate_buffer structs.
*
* Tries to reserve bos pointed to by the list entries for validation.
--
1.7.10.4
