From d2a82d9da7dbe2759d7bdd400cc835229e904c07 Mon Sep 17 00:00:00 2001
From: Vijay Pai <vpai@google.com>
Date: Wed, 17 Jun 2015 13:42:46 -0700
Subject: [PATCH] Added comments to describe nesting of mutexes
---
src/core/surface/server.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/src/core/surface/server.c b/src/core/surface/server.c
index dac374b7d4..bb510b9ebf 100644
--- a/src/core/surface/server.c
+++ b/src/core/surface/server.c
@@ -141,8 +141,15 @@ struct grpc_server {
grpc_pollset **pollsets;
size_t cq_count;
- gpr_mu mu_global;
- gpr_mu mu_call;
+ /* The two following mutexes control access to server-state
+ mu_global controls access to non-call-related state (e.g., channel state)
+ mu_call controls access to call-related state (e.g., the call lists)
+
+ If they are ever required to be nested, you must lock mu_global
+ before mu_call. This is currently used in shutdown processing
+ (grpc_server_shutdown_and_notify and maybe_finish_shutdown) */
+ gpr_mu mu_global; /* mutex for server and channel state */
+ gpr_mu mu_call; /* mutex for call-specific state */
registered_method *registered_methods;
requested_call_array requested_calls;
--
GitLab