diff --git a/include/haproxy/shctx-t.h b/include/haproxy/shctx-t.h
index 9d23d69d0..da241a9ac 100644
--- a/include/haproxy/shctx-t.h
+++ b/include/haproxy/shctx-t.h
@@ -51,6 +51,7 @@ struct shared_context {
 	unsigned int nbav;  /* number of available blocks */
 	unsigned int max_obj_size;   /* maximum object size (in bytes). */
 	void (*free_block)(struct shared_block *first, struct shared_block *block, void *data);
+	void (*reserve_finish)(struct shared_context *shctx);
 	void *cb_data;
 	short int block_size;
 	unsigned char data[VAR_ARRAY];
diff --git a/src/shctx.c b/src/shctx.c
index daf7866c9..299f57f2a 100644
--- a/src/shctx.c
+++ b/src/shctx.c
@@ -110,6 +110,9 @@ struct shared_block *shctx_row_reserve_hot(struct shared_context *shctx,
 
 	shctx_wrunlock(shctx);
 
+	if (shctx->reserve_finish)
+		shctx->reserve_finish(shctx);
+
 out:
 	return ret;
 }