release/20.x: [Offload] Stop the RPC server faiilng with more than one GPU (#125982)

[llvmbot]

Backport 7a87794

Requested by: @jhuber6

[llvmbot]

@ronlieb What do you think about merging this PR to the release branch?

[llvmbot]

@llvm/pr-subscribers-offload

Author: None (llvmbot)

Changes

Backport 7a87794

Requested by: @jhuber6

---

Full diff: https://github.com/llvm/llvm-project/pull/125985.diff

1 Files Affected:

• (modified) offload/plugins-nextgen/common/src/PluginInterface.cpp (+4-3)

diff --git a/offload/plugins-nextgen/common/src/PluginInterface.cpp b/offload/plugins-nextgen/common/src/PluginInterface.cpp
index 16f510de3ecc5ca..57672b0223bec81 100644
--- a/offload/plugins-nextgen/common/src/PluginInterface.cpp
+++ b/offload/plugins-nextgen/common/src/PluginInterface.cpp
@@ -1057,8 +1057,9 @@ Error GenericDeviceTy::setupRPCServer(GenericPluginTy &Plugin,
   if (auto Err = Server.initDevice(*this, Plugin.getGlobalHandler(), Image))
     return Err;
 
-  if (auto Err = Server.startThread())
-    return Err;
+  if (!Server.Thread->Running.load(std::memory_order_acquire))
+    if (auto Err = Server.startThread())
+      return Err;
 
   RPCServer = &Server;
   DP("Running an RPC server on device %d\n", getDeviceId());
@@ -1633,7 +1634,7 @@ Error GenericPluginTy::deinit() {
   if (GlobalHandler)
     delete GlobalHandler;
 
-  if (RPCServer && RPCServer->Thread->Running.load(std::memory_order_relaxed))
+  if (RPCServer && RPCServer->Thread->Running.load(std::memory_order_acquire))
     if (Error Err = RPCServer->shutDown())
       return Err;
 

[github-actions]

@jhuber6 (or anyone else). If you would like to add a note about this fix in the release notes (completely optional). Please reply to this comment with a one or two sentence description of the fix. When you are done, please add the release:note label to this PR.