Otherwise we can encounter out of memory situations under extreme load.
v2: add documentation for the new function
Signed-off-by: Christian König deathsimple@vodafone.de --- drivers/gpu/drm/radeon/radeon.h | 2 +- drivers/gpu/drm/radeon/radeon_sa.c | 82 ++++++++++++++++++++++++++---------- 2 files changed, 61 insertions(+), 23 deletions(-)
diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h index 6715e4c..2cb355b 100644 --- a/drivers/gpu/drm/radeon/radeon.h +++ b/drivers/gpu/drm/radeon/radeon.h @@ -362,7 +362,7 @@ struct radeon_bo_list { * alignment). */ struct radeon_sa_manager { - spinlock_t lock; + wait_queue_head_t wq; struct radeon_bo *bo; struct list_head *hole; struct list_head flist[RADEON_NUM_RINGS]; diff --git a/drivers/gpu/drm/radeon/radeon_sa.c b/drivers/gpu/drm/radeon/radeon_sa.c index 81dbb5b..4e77124 100644 --- a/drivers/gpu/drm/radeon/radeon_sa.c +++ b/drivers/gpu/drm/radeon/radeon_sa.c @@ -54,7 +54,7 @@ int radeon_sa_bo_manager_init(struct radeon_device *rdev, { int i, r;
- spin_lock_init(&sa_manager->lock); + init_waitqueue_head(&sa_manager->wq); sa_manager->bo = NULL; sa_manager->size = size; sa_manager->domain = domain; @@ -211,6 +211,39 @@ static bool radeon_sa_bo_try_alloc(struct radeon_sa_manager *sa_manager, return false; }
+/** + * radeon_sa_event - Check if we can stop waiting + * + * @sa_manager: pointer to the sa_manager + * @size: number of bytes we want to allocate + * @align: alignment we need to match + * + * Check if either there is a fence we can wait for or + * enough free memory to satisfy the allocation directly + */ +static bool radeon_sa_event(struct radeon_sa_manager *sa_manager, + unsigned size, unsigned align) +{ + unsigned soffset, eoffset, wasted; + int i; + + for (i = 0; i < RADEON_NUM_RINGS; ++i) { + if (!list_empty(&sa_manager->flist[i])) { + return true; + } + } + + soffset = radeon_sa_bo_hole_soffset(sa_manager); + eoffset = radeon_sa_bo_hole_eoffset(sa_manager); + wasted = (align - (soffset % align)) % align; + + if ((eoffset - soffset) >= (size + wasted)) { + return true; + } + + return false; +} + static bool radeon_sa_bo_next_hole(struct radeon_sa_manager *sa_manager, struct radeon_fence **fences, unsigned *tries) @@ -297,8 +330,8 @@ int radeon_sa_bo_new(struct radeon_device *rdev, INIT_LIST_HEAD(&(*sa_bo)->olist); INIT_LIST_HEAD(&(*sa_bo)->flist);
- spin_lock(&sa_manager->lock); - do { + spin_lock(&sa_manager->wq.lock); + while(1) { for (i = 0; i < RADEON_NUM_RINGS; ++i) { fences[i] = NULL; tries[i] = 0; @@ -309,30 +342,34 @@ int radeon_sa_bo_new(struct radeon_device *rdev,
if (radeon_sa_bo_try_alloc(sa_manager, *sa_bo, size, align)) { - spin_unlock(&sa_manager->lock); + spin_unlock(&sa_manager->wq.lock); return 0; }
/* see if we can skip over some allocations */ } while (radeon_sa_bo_next_hole(sa_manager, fences, tries));
- if (block) { - spin_unlock(&sa_manager->lock); - r = radeon_fence_wait_any(rdev, fences, false); - spin_lock(&sa_manager->lock); - if (r) { - /* if we have nothing to wait for we - are practically out of memory */ - if (r == -ENOENT) { - r = -ENOMEM; - } - goto out_err; - } + if (!block) { + break; + } + + spin_unlock(&sa_manager->wq.lock); + r = radeon_fence_wait_any(rdev, fences, false); + spin_lock(&sa_manager->wq.lock); + /* if we have nothing to wait for block */ + if (r == -ENOENT) { + r = wait_event_interruptible_locked( + sa_manager->wq, + radeon_sa_event(sa_manager, size, align) + ); + } + if (r) { + goto out_err; } - } while (block); + };
out_err: - spin_unlock(&sa_manager->lock); + spin_unlock(&sa_manager->wq.lock); kfree(*sa_bo); *sa_bo = NULL; return r; @@ -348,7 +385,7 @@ void radeon_sa_bo_free(struct radeon_device *rdev, struct radeon_sa_bo **sa_bo, }
sa_manager = (*sa_bo)->manager; - spin_lock(&sa_manager->lock); + spin_lock(&sa_manager->wq.lock); if (fence && !radeon_fence_signaled(fence)) { (*sa_bo)->fence = radeon_fence_ref(fence); list_add_tail(&(*sa_bo)->flist, @@ -356,7 +393,8 @@ void radeon_sa_bo_free(struct radeon_device *rdev, struct radeon_sa_bo **sa_bo, } else { radeon_sa_bo_remove_locked(*sa_bo); } - spin_unlock(&sa_manager->lock); + wake_up_all_locked(&sa_manager->wq); + spin_unlock(&sa_manager->wq.lock); *sa_bo = NULL; }
@@ -366,7 +404,7 @@ void radeon_sa_bo_dump_debug_info(struct radeon_sa_manager *sa_manager, { struct radeon_sa_bo *i;
- spin_lock(&sa_manager->lock); + spin_lock(&sa_manager->wq.lock); list_for_each_entry(i, &sa_manager->olist, olist) { if (&i->olist == sa_manager->hole) { seq_printf(m, ">"); @@ -381,6 +419,6 @@ void radeon_sa_bo_dump_debug_info(struct radeon_sa_manager *sa_manager, } seq_printf(m, "\n"); } - spin_unlock(&sa_manager->lock); + spin_unlock(&sa_manager->wq.lock); } #endif