summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorChris Wilson <chris@chris-wilson.co.uk>2017-06-30 00:12:53 +0300
committerGustavo Padovan <gustavo.padovan@collabora.com>2017-06-30 00:54:07 +0300
commitf1e8c67123cf171e2b0357e885e426328b241d7d (patch)
tree0b5b3e4c46496558bc2f20c2bf91a9f994d569a4
parentd3862e44daa7a0c94d2f6193502a8c49379acfce (diff)
downloadlinux-f1e8c67123cf171e2b0357e885e426328b241d7d.tar.xz
dma-buf/sw-sync: Use an rbtree to sort fences in the timeline
Reduce the list iteration when incrementing the timeline by storing the fences in increasing order. v2: Prevent spinlock recursion on free during create v3: Fixup rebase conflict inside comments that escaped the compiler. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Sean Paul <seanpaul@chromium.org> Cc: Gustavo Padovan <gustavo@padovan.org> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170629211253.22766-1-chris@chris-wilson.co.uk
-rw-r--r--drivers/dma-buf/sw_sync.c49
-rw-r--r--drivers/dma-buf/sync_debug.h5
2 files changed, 48 insertions, 6 deletions
diff --git a/drivers/dma-buf/sw_sync.c b/drivers/dma-buf/sw_sync.c
index f20d18c421a3..af1bc84802e5 100644
--- a/drivers/dma-buf/sw_sync.c
+++ b/drivers/dma-buf/sw_sync.c
@@ -96,6 +96,7 @@ static struct sync_timeline *sync_timeline_create(const char *name)
obj->context = dma_fence_context_alloc(1);
strlcpy(obj->name, name, sizeof(obj->name));
+ obj->pt_tree = RB_ROOT;
INIT_LIST_HEAD(&obj->pt_list);
spin_lock_init(&obj->lock);
@@ -142,9 +143,13 @@ static void sync_timeline_signal(struct sync_timeline *obj, unsigned int inc)
obj->value += inc;
- list_for_each_entry_safe(pt, next, &obj->pt_list, link)
- if (dma_fence_is_signaled_locked(&pt->base))
- list_del_init(&pt->link);
+ list_for_each_entry_safe(pt, next, &obj->pt_list, link) {
+ if (!dma_fence_is_signaled_locked(&pt->base))
+ break;
+
+ list_del_init(&pt->link);
+ rb_erase(&pt->node, &obj->pt_tree);
+ }
spin_unlock_irq(&obj->lock);
}
@@ -174,8 +179,38 @@ static struct sync_pt *sync_pt_create(struct sync_timeline *obj,
INIT_LIST_HEAD(&pt->link);
spin_lock_irq(&obj->lock);
- if (!dma_fence_is_signaled_locked(&pt->base))
- list_add_tail(&pt->link, &obj->pt_list);
+ if (!dma_fence_is_signaled_locked(&pt->base)) {
+ struct rb_node **p = &obj->pt_tree.rb_node;
+ struct rb_node *parent = NULL;
+
+ while (*p) {
+ struct sync_pt *other;
+ int cmp;
+
+ parent = *p;
+ other = rb_entry(parent, typeof(*pt), node);
+ cmp = value - other->base.seqno;
+ if (cmp > 0) {
+ p = &parent->rb_right;
+ } else if (cmp < 0) {
+ p = &parent->rb_left;
+ } else {
+ if (dma_fence_get_rcu(&other->base)) {
+ dma_fence_put(&pt->base);
+ pt = other;
+ goto unlock;
+ }
+ p = &parent->rb_left;
+ }
+ }
+ rb_link_node(&pt->node, parent, p);
+ rb_insert_color(&pt->node, &obj->pt_tree);
+
+ parent = rb_next(&pt->node);
+ list_add_tail(&pt->link,
+ parent ? &rb_entry(parent, typeof(*pt), node)->link : &obj->pt_list);
+ }
+unlock:
spin_unlock_irq(&obj->lock);
return pt;
@@ -202,8 +237,10 @@ static void timeline_fence_release(struct dma_fence *fence)
unsigned long flags;
spin_lock_irqsave(fence->lock, flags);
- if (!list_empty(&pt->link))
+ if (!list_empty(&pt->link)) {
list_del(&pt->link);
+ rb_erase(&pt->node, &parent->pt_tree);
+ }
spin_unlock_irqrestore(fence->lock, flags);
}
diff --git a/drivers/dma-buf/sync_debug.h b/drivers/dma-buf/sync_debug.h
index 6a2a8e69a7d0..d615a89f774c 100644
--- a/drivers/dma-buf/sync_debug.h
+++ b/drivers/dma-buf/sync_debug.h
@@ -14,6 +14,7 @@
#define _LINUX_SYNC_H
#include <linux/list.h>
+#include <linux/rbtree.h>
#include <linux/spinlock.h>
#include <linux/dma-fence.h>
@@ -25,6 +26,7 @@
* @kref: reference count on fence.
* @name: name of the sync_timeline. Useful for debugging
* @lock: lock protecting @pt_list and @value
+ * @pt_tree: rbtree of active (unsignaled/errored) sync_pts
* @pt_list: list of active (unsignaled/errored) sync_pts
* @sync_timeline_list: membership in global sync_timeline_list
*/
@@ -36,6 +38,7 @@ struct sync_timeline {
u64 context;
int value;
+ struct rb_root pt_tree;
struct list_head pt_list;
spinlock_t lock;
@@ -51,10 +54,12 @@ static inline struct sync_timeline *dma_fence_parent(struct dma_fence *fence)
* struct sync_pt - sync_pt object
* @base: base fence object
* @link: link on the sync timeline's list
+ * @node: node in the sync timeline's tree
*/
struct sync_pt {
struct dma_fence base;
struct list_head link;
+ struct rb_node node;
};
#ifdef CONFIG_SW_SYNC