From 9afb8e29e22a49f271f06144a1799de40c59a415 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Reynir=20Bj=C3=B6rnsson?= <reynir@reynir.dk>
Date: Tue, 29 Oct 2024 10:10:17 +0100
Subject: [PATCH] Document change_and_push_waiter details

---
 src/git_kv.ml | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/git_kv.ml b/src/git_kv.ml
index 33fa5fc..a510974 100644
--- a/src/git_kv.ml
+++ b/src/git_kv.ml
@@ -679,7 +679,11 @@ module Make (Pclock : Mirage_clock.PCLOCK) = struct
     | None ->
       (* XXX(dinosaure): serialize [change_and_push]. If we do
          [Lwt.both (change_and_push ..) (change_and_push ..)], they can not run
-         concurrently! The second will waiting the first to finish. *)
+         concurrently! The second will waiting the first to finish.
+         (reynir): Furthermore, we need to create a new task and update
+         [change_and_push_waiter] before we wait on the existing
+         [change_and_push_waiter] task without any yield point in between to
+         ensure serializability. *)
       let th, wk = Lwt.wait () in
       let th' = t.change_and_push_waiter in
       t.change_and_push_waiter <- Some th;