buflib: update first_free_handle in handle_alloc

Since we're scanning the handle table for the first free slot,
we know none of the scanned slots are free. Use that knowledge
to update first_free_handle and avoid rescanning filled slots
again when the next handle is allocated.

Change-Id: I457372f66c231168cfffa7e905d1e9fb80002f5f

1 files changed, 9 insertions, 0 deletions

diff --git a/firmware/buflib.c b/firmware/buflib.c
index 05e489ea14..4b557eb59d 100644
--- a/firmware/buflib.c
+++ b/firmware/buflib.c
@@ -196,8 +196,17 @@ union buflib_data* handle_alloc(struct buflib_context *ctx)
         if (handle >= ctx->alloc_end)
             ctx->last_handle--;
         else
+        {
+            /* We know the table is full, so update first_free_handle */
+            ctx->first_free_handle = ctx->last_handle - 1;
             return NULL;
+        }
     }
+
+    /* We know there are no free handles between the old first_free_handle
+     * and the found handle, therefore we can update first_free_handle */
+    ctx->first_free_handle = handle - 1;
+
     handle->val = -1;
     return handle;
 }