Merge branch 'backup_wrap_concurrency' into 'master'

Fix race condition in concurrent backups

Closes #238847

See merge request gitlab-org/gitlab!39894

changelogs/unreleased/backup_wrap_concurrency.yml

+---
+title: Fix race condition in concurrent backups
+merge_request: 39894
+author:
+type: fixed

lib/backup/repository.rb

@@ -26,13 +26,17 @@ module Backup
 
       threads = Gitlab.config.repositories.storages.keys.map do |storage|
         Thread.new do
+          Rails.application.executor.wrap do
             dump_storage(storage, semaphore, max_storage_concurrency: max_storage_concurrency)
           rescue => e
             errors << e
           end
         end
+      end
 
+      ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
         threads.each(&:join)
+      end
 
       raise errors.pop unless errors.empty?
     end
@@ -155,6 +159,7 @@ module Backup
 
       threads = Array.new(max_storage_concurrency) do
         Thread.new do
+          Rails.application.executor.wrap do
             while project = queue.pop
               semaphore.acquire
 
@@ -169,6 +174,7 @@ module Backup
             end
           end
         end
+      end
 
       Project.for_repository_storage(storage).find_each(batch_size: 100) do |project|
         break unless errors.empty?
@@ -177,7 +183,9 @@ module Backup
       end
 
       queue.close
+      ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
         threads.each(&:join)
+      end
 
       raise errors.pop unless errors.empty?
     end