From eaf270c6489ff9b4b61d55e5d2ee1255941d9aee Mon Sep 17 00:00:00 2001
From: Christian Schwarz <christian@neon.tech>
Date: Thu, 25 May 2023 14:57:41 +0200
Subject: [PATCH] Revert "use tokio::sync::watch::Receiver::wait_for"

This reverts commit fe4ef121b6c4ffeaf9175001c463cfdc598164d1.
---
 pageserver/src/tenant.rs | 23 +++++++++++++----------
 1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/pageserver/src/tenant.rs b/pageserver/src/tenant.rs
index 5fba3026cd..f58fc138ee 100644
--- a/pageserver/src/tenant.rs
+++ b/pageserver/src/tenant.rs
@@ -1704,12 +1704,15 @@ impl Tenant {
     ///
     /// This function is not cancel-safe!
     pub async fn set_stopping(&self) {
-        // `Activating` is a transient state during which no external state transitions are supported.
+        // Get the rx before checking state inside send_if_modified.
+        // This way, when we later rx.changed().await, we won't have missed
+        // any state changes.
         let mut rx = self.state.subscribe();
-        rx.wait_for(|state| state != TenantState::Activating)
-            .await
-            .expect("cannot drop self.state while on a &self method");
-
+        while *rx.borrow() == TenantState::Activating {
+            rx.changed()
+                .await
+                .expect("we're a method on Tenant, so, we're keeping self.state alive here");
+        }
         let mut stopping = false;
         self.state.send_modify(|current_state| {
             match current_state {
@@ -1747,12 +1750,12 @@ impl Tenant {
     }
 
     pub async fn set_broken(&self, reason: String) {
-        // `Activating` is a transient state during which no external state transitions are supported.
         let mut rx = self.state.subscribe();
-        rx.wait_for(|state| state != TenantState::Activating)
-            .await
-            .expect("cannot drop self.state while on a &self method");
-
+        while *rx.borrow() == TenantState::Activating {
+            rx.changed()
+                .await
+                .expect("we're a method on Tenant, so, we're keeping self.state alive here");
+        }
         self.state.send_modify(|current_state| {
             match *current_state {
                 TenantState::Activating => {