Btrfs: use fastpath in extent state ops as much as possible

Fully utilize our extent state's new helper functions to use
fastpath as much as possible.

Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@redhat.com>

1 files changed, 18 insertions, 26 deletions

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 7af93435cee0..69a527c7a0b3 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -569,10 +569,8 @@ hit_next:
                 if (err)
                         goto out;
                 if (state->end <= end) {
-                        clear_state_bit(tree, state, &bits, wake);
-                        if (last_end == (u64)-1)
-                                goto out;
-                        start = last_end + 1;
+                        state = clear_state_bit(tree, state, &bits, wake);
+                        goto next;
                 }
                 goto search_again;
         }
@@ -780,7 +778,6 @@ hit_next:
          * Just lock what we found and keep going
          */
         if (state->start == start && state->end <= end) {
-                struct rb_node *next_node;
                 if (state->state & exclusive_bits) {
                         *failed_start = state->start;
                         err = -EEXIST;
@@ -788,20 +785,15 @@ hit_next:
                 }
 
                 set_state_bits(tree, state, &bits);
-
                 cache_state(state, cached_state);
                 merge_state(tree, state);
                 if (last_end == (u64)-1)
                         goto out;
-
                 start = last_end + 1;
-                next_node = rb_next(&state->rb_node);
-                if (next_node && start < end && prealloc && !need_resched()) {
-                        state = rb_entry(next_node, struct extent_state,
-                                         rb_node);
-                        if (state->start == start)
-                                goto hit_next;
-                }
+                state = next_state(state);
+                if (start < end && state && state->start == start &&
+                    !need_resched())
+                        goto hit_next;
                 goto search_again;
         }
 
@@ -844,6 +836,10 @@ hit_next:
                         if (last_end == (u64)-1)
                                 goto out;
                         start = last_end + 1;
+                        state = next_state(state);
+                        if (start < end && state && state->start == start &&
+                            !need_resched())
+                                goto hit_next;
                 }
                 goto search_again;
         }
@@ -993,21 +989,14 @@ hit_next:
          * Just lock what we found and keep going
          */
         if (state->start == start && state->end <= end) {
-                struct rb_node *next_node;
-
                 set_state_bits(tree, state, &bits);
-                clear_state_bit(tree, state, &clear_bits, 0);
+                state = clear_state_bit(tree, state, &clear_bits, 0);
                 if (last_end == (u64)-1)
                         goto out;
-
                 start = last_end + 1;
-                next_node = rb_next(&state->rb_node);
-                if (next_node && start < end && prealloc && !need_resched()) {
-                        state = rb_entry(next_node, struct extent_state,
-                                         rb_node);
-                        if (state->start == start)
-                                goto hit_next;
-                }
+                if (start < end && state && state->start == start &&
+                    !need_resched())
+                        goto hit_next;
                 goto search_again;
         }
 
@@ -1041,10 +1030,13 @@ hit_next:
                         goto out;
                 if (state->end <= end) {
                         set_state_bits(tree, state, &bits);
-                        clear_state_bit(tree, state, &clear_bits, 0);
+                        state = clear_state_bit(tree, state, &clear_bits, 0);
                         if (last_end == (u64)-1)
                                 goto out;
                         start = last_end + 1;
+                        if (start < end && state && state->start == start &&
+                            !need_resched())
+                                goto hit_next;
                 }
                 goto search_again;
         }