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src/core/iomgr/pollset_posix.c

@@ -106,8 +106,11 @@ void grpc_pollset_init(grpc_pollset *pollset) {
 void grpc_pollset_add_fd(grpc_pollset *pollset, grpc_fd *fd) {
   gpr_mu_lock(&pollset->mu);
   pollset->vtable->add_fd(pollset, fd, 1);
+  /* the following (enabled only in debug) will reacquire and then releast
+     our lock - meaning that if the unlocking flag passed to del_fd above is
+     not respected, the code will deadlock (in a way that we have a chance of
+     debugging) */
 #ifndef NDEBUG
-  /* this will deadlock if the unlocking rules aren't correctly implemented */
   gpr_mu_lock(&pollset->mu);
   gpr_mu_unlock(&pollset->mu);
 #endif
@@ -116,8 +119,11 @@ void grpc_pollset_add_fd(grpc_pollset *pollset, grpc_fd *fd) {
 void grpc_pollset_del_fd(grpc_pollset *pollset, grpc_fd *fd) {
   gpr_mu_lock(&pollset->mu);
   pollset->vtable->del_fd(pollset, fd, 1);
+  /* the following (enabled only in debug) will reacquire and then releast
+     our lock - meaning that if the unlocking flag passed to del_fd above is
+     not respected, the code will deadlock (in a way that we have a chance of
+     debugging) */
 #ifndef NDEBUG
-  /* this will deadlock if the unlocking rules aren't correctly implemented */
   gpr_mu_lock(&pollset->mu);
   gpr_mu_unlock(&pollset->mu);
 #endif