Label all iomgr objects

This allows a list of them to be dumped to isolate where memory leaks
are occuring.

9 files changed, 117 insertions, 45 deletions

diff --git a/src/core/iomgr/endpoint_pair.h b/src/core/iomgr/endpoint_pair.h
index dffbd36d4c..25087be0c7 100644
--- a/src/core/iomgr/endpoint_pair.h
+++ b/src/core/iomgr/endpoint_pair.h
@@ -41,6 +41,7 @@ typedef struct {
   grpc_endpoint *server;
 } grpc_endpoint_pair;
 
-grpc_endpoint_pair grpc_iomgr_create_endpoint_pair(size_t read_slice_size);
+grpc_endpoint_pair grpc_iomgr_create_endpoint_pair(const char *name,
+                                                   size_t read_slice_size);
 
 #endif  /* GRPC_INTERNAL_CORE_IOMGR_ENDPOINT_PAIR_H */
diff --git a/src/core/iomgr/endpoint_pair_posix.c b/src/core/iomgr/endpoint_pair_posix.c
index ac511b97b2..9b3b63f1e7 100644
--- a/src/core/iomgr/endpoint_pair_posix.c
+++ b/src/core/iomgr/endpoint_pair_posix.c
@@ -44,6 +44,8 @@
 #include <sys/socket.h>
 
 #include "src/core/iomgr/tcp_posix.h"
+#include "src/core/support/string.h"
+#include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
 
 static void create_sockets(int sv[2]) {
@@ -55,12 +57,21 @@ static void create_sockets(int sv[2]) {
   GPR_ASSERT(fcntl(sv[1], F_SETFL, flags | O_NONBLOCK) == 0);
 }
 
-grpc_endpoint_pair grpc_iomgr_create_endpoint_pair(size_t read_slice_size) {
+grpc_endpoint_pair grpc_iomgr_create_endpoint_pair(const char *name,
+                                                   size_t read_slice_size) {
   int sv[2];
   grpc_endpoint_pair p;
+  char *final_name;
   create_sockets(sv);
-  p.client = grpc_tcp_create(grpc_fd_create(sv[1]), read_slice_size);
-  p.server = grpc_tcp_create(grpc_fd_create(sv[0]), read_slice_size);
+
+  gpr_asprintf(&final_name, "%s:client", name);
+  p.client =
+      grpc_tcp_create(grpc_fd_create(sv[1], final_name), read_slice_size);
+  gpr_free(final_name);
+  gpr_asprintf(&final_name, "%s:server", name);
+  p.server =
+      grpc_tcp_create(grpc_fd_create(sv[0], final_name), read_slice_size);
+  gpr_free(final_name);
   return p;
 }
 
diff --git a/src/core/iomgr/fd_posix.c b/src/core/iomgr/fd_posix.c
index b697fcc64a..4ba06676ab 100644
--- a/src/core/iomgr/fd_posix.c
+++ b/src/core/iomgr/fd_posix.c
@@ -41,7 +41,6 @@
 #include <sys/socket.h>
 #include <unistd.h>
 
-#include "src/core/iomgr/iomgr_internal.h"
 #include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
 #include <grpc/support/useful.h>
@@ -119,7 +118,7 @@ static void unref_by(grpc_fd *fd, int n) {
     close(fd->fd);
     grpc_iomgr_add_callback(fd->on_done, fd->on_done_user_data);
     freelist_fd(fd);
-    grpc_iomgr_unref();
+    grpc_iomgr_unregister_object(&fd->iomgr_object);
   } else {
     GPR_ASSERT(old > n);
   }
@@ -138,9 +137,9 @@ void grpc_fd_global_shutdown(void) {
 
 static void do_nothing(void *ignored, int success) {}
 
-grpc_fd *grpc_fd_create(int fd) {
+grpc_fd *grpc_fd_create(int fd, const char *name) {
   grpc_fd *r = alloc_fd(fd);
-  grpc_iomgr_ref();
+  grpc_iomgr_register_object(&r->iomgr_object, name);
   grpc_pollset_add_fd(grpc_backup_pollset(), r);
   return r;
 }
diff --git a/src/core/iomgr/fd_posix.h b/src/core/iomgr/fd_posix.h
index cfc533b7f5..a15ed7c90d 100644
--- a/src/core/iomgr/fd_posix.h
+++ b/src/core/iomgr/fd_posix.h
@@ -34,7 +34,7 @@
 #ifndef GRPC_INTERNAL_CORE_IOMGR_FD_POSIX_H
 #define GRPC_INTERNAL_CORE_IOMGR_FD_POSIX_H
 
-#include "src/core/iomgr/iomgr.h"
+#include "src/core/iomgr/iomgr_internal.h"
 #include "src/core/iomgr/pollset.h"
 #include <grpc/support/atm.h>
 #include <grpc/support/sync.h>
@@ -99,12 +99,14 @@ struct grpc_fd {
   grpc_iomgr_cb_func on_done;
   void *on_done_user_data;
   struct grpc_fd *freelist_next;
+
+  grpc_iomgr_object iomgr_object;
 };
 
 /* Create a wrapped file descriptor.
    Requires fd is a non-blocking file descriptor.
    This takes ownership of closing fd. */
-grpc_fd *grpc_fd_create(int fd);
+grpc_fd *grpc_fd_create(int fd, const char *name);
 
 /* Releases fd to be asynchronously destroyed.
    on_done is called when the underlying file descriptor is definitely close()d.
diff --git a/src/core/iomgr/iomgr.c b/src/core/iomgr/iomgr.c
index d22542fc91..1377b6dc9e 100644
--- a/src/core/iomgr/iomgr.c
+++ b/src/core/iomgr/iomgr.c
@@ -37,6 +37,7 @@
 
 #include "src/core/iomgr/iomgr_internal.h"
 #include "src/core/iomgr/alarm_internal.h"
+#include "src/core/support/string.h"
 #include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
 #include <grpc/support/thd.h>
@@ -54,8 +55,8 @@ static gpr_cv g_rcv;
 static delayed_callback *g_cbs_head = NULL;
 static delayed_callback *g_cbs_tail = NULL;
 static int g_shutdown;
-static int g_refs;
 static gpr_event g_background_callback_executor_done;
+static grpc_iomgr_object g_root_object;
 
 /* Execute followup callbacks continuously.
    Other threads may check in and help during pollset_work() */
@@ -96,34 +97,49 @@ void grpc_iomgr_init(void) {
   gpr_mu_init(&g_mu);
   gpr_cv_init(&g_rcv);
   grpc_alarm_list_init(gpr_now());
-  g_refs = 0;
+  g_root_object.next = g_root_object.prev = &g_root_object;
+  g_root_object.name = "root";
   grpc_iomgr_platform_init();
   gpr_event_init(&g_background_callback_executor_done);
   gpr_thd_new(&id, background_callback_executor, NULL, NULL);
 }
 
+static size_t count_objects(void) {
+  grpc_iomgr_object *obj;
+  size_t n = 0;
+  for (obj = g_root_object.next; obj != &g_root_object; obj = obj->next) {
+    n++;
+  }
+  return n;
+}
+
 void grpc_iomgr_shutdown(void) {
   delayed_callback *cb;
+  grpc_iomgr_object *obj;
   gpr_timespec shutdown_deadline =
       gpr_time_add(gpr_now(), gpr_time_from_seconds(10));
 
 
   gpr_mu_lock(&g_mu);
   g_shutdown = 1;
-  while (g_cbs_head || g_refs) {
-    gpr_log(GPR_DEBUG, "Waiting for %d iomgr objects to be destroyed%s", g_refs,
+  while (g_cbs_head || g_root_object.next != &g_root_object) {
+    size_t nobjs = count_objects();
+    gpr_log(GPR_DEBUG, "Waiting for %d iomgr objects to be destroyed%s", nobjs,
             g_cbs_head ? " and executing final callbacks" : "");
-    while (g_cbs_head) {
-      cb = g_cbs_head;
-      g_cbs_head = cb->next;
-      if (!g_cbs_head) g_cbs_tail = NULL;
-      gpr_mu_unlock(&g_mu);
-
-      cb->cb(cb->cb_arg, 0);
-      gpr_free(cb);
-      gpr_mu_lock(&g_mu);
+    if (g_cbs_head) {
+      do {
+        cb = g_cbs_head;
+        g_cbs_head = cb->next;
+        if (!g_cbs_head) g_cbs_tail = NULL;
+        gpr_mu_unlock(&g_mu);
+
+        cb->cb(cb->cb_arg, 0);
+        gpr_free(cb);
+        gpr_mu_lock(&g_mu);
+      } while (g_cbs_head);
+      continue;
     }
-    if (g_refs) {
+    if (nobjs > 0) {
       int timeout = 0;
       gpr_timespec short_deadline = gpr_time_add(gpr_now(),
                                                  gpr_time_from_millis(100));
@@ -137,7 +153,10 @@ void grpc_iomgr_shutdown(void) {
         gpr_log(GPR_DEBUG,
                 "Failed to free %d iomgr objects before shutdown deadline: "
                 "memory leaks are likely",
-                g_refs);
+                count_objects());
+        for (obj = g_root_object.next; obj != &g_root_object; obj = obj->next) {
+          gpr_log(GPR_DEBUG, "LEAKED OBJECT: %s", obj->name);
+        }
         break;
       }
     }
@@ -153,17 +172,21 @@ void grpc_iomgr_shutdown(void) {
   gpr_cv_destroy(&g_rcv);
 }
 
-void grpc_iomgr_ref(void) {
+void grpc_iomgr_register_object(grpc_iomgr_object *obj, const char *name) {
+  obj->name = gpr_strdup(name);
   gpr_mu_lock(&g_mu);
-  ++g_refs;
+  obj->next = &g_root_object;
+  obj->prev = obj->next->prev;
+  obj->next->prev = obj->prev->next = obj;
   gpr_mu_unlock(&g_mu);
 }
 
-void grpc_iomgr_unref(void) {
+void grpc_iomgr_unregister_object(grpc_iomgr_object *obj) {
+  gpr_free(obj->name);
   gpr_mu_lock(&g_mu);
-  if (0 == --g_refs) {
-    gpr_cv_signal(&g_rcv);
-  }
+  obj->next->prev = obj->prev;
+  obj->prev->next = obj->next;
+  gpr_cv_signal(&g_rcv);
   gpr_mu_unlock(&g_mu);
 }
 
diff --git a/src/core/iomgr/iomgr_internal.h b/src/core/iomgr/iomgr_internal.h
index 07923258b9..54eadf1edc 100644
--- a/src/core/iomgr/iomgr_internal.h
+++ b/src/core/iomgr/iomgr_internal.h
@@ -38,12 +38,18 @@
 #include "src/core/iomgr/iomgr_internal.h"
 #include <grpc/support/sync.h>
 
+typedef struct grpc_iomgr_object {
+  char *name;
+  struct grpc_iomgr_object *next;
+  struct grpc_iomgr_object *prev;
+} grpc_iomgr_object;
+
 int grpc_maybe_call_delayed_callbacks(gpr_mu *drop_mu, int success);
 void grpc_iomgr_add_delayed_callback(grpc_iomgr_cb_func cb, void *cb_arg,
                                      int success);
 
-void grpc_iomgr_ref(void);
-void grpc_iomgr_unref(void);
+void grpc_iomgr_register_object(grpc_iomgr_object *obj, const char *name);
+void grpc_iomgr_unregister_object(grpc_iomgr_object *obj);
 
 void grpc_iomgr_platform_init(void);
 void grpc_iomgr_platform_shutdown(void);
diff --git a/src/core/iomgr/resolve_address_posix.c b/src/core/iomgr/resolve_address_posix.c
index 9a9283c93c..fcf48fe0d7 100644
--- a/src/core/iomgr/resolve_address_posix.c
+++ b/src/core/iomgr/resolve_address_posix.c
@@ -55,6 +55,7 @@ typedef struct {
   char *default_port;
   grpc_resolve_cb cb;
   void *arg;
+  grpc_iomgr_object iomgr_object;
 } request;
 
 grpc_resolved_addresses *grpc_blocking_resolve_address(
@@ -153,9 +154,9 @@ static void do_request(void *rp) {
   grpc_resolve_cb cb = r->cb;
   gpr_free(r->name);
   gpr_free(r->default_port);
+  grpc_iomgr_unregister_object(&r->iomgr_object);
   gpr_free(r);
   cb(arg, resolved);
-  grpc_iomgr_unref();
 }
 
 void grpc_resolved_addresses_destroy(grpc_resolved_addresses *addrs) {
@@ -167,7 +168,11 @@ void grpc_resolve_address(const char *name, const char *default_port,
                           grpc_resolve_cb cb, void *arg) {
   request *r = gpr_malloc(sizeof(request));
   gpr_thd_id id;
-  grpc_iomgr_ref();
+  char *tmp;
+  gpr_asprintf(&tmp, "resolve_address:name='%s':default_port='%s'", name,
+               default_port);
+  grpc_iomgr_register_object(&r->iomgr_object, tmp);
+  gpr_free(tmp);
   r->name = gpr_strdup(name);
   r->default_port = gpr_strdup(default_port);
   r->cb = cb;
diff --git a/src/core/iomgr/tcp_client_posix.c b/src/core/iomgr/tcp_client_posix.c
index 2401fe00e4..aa21ba9b9e 100644
--- a/src/core/iomgr/tcp_client_posix.c
+++ b/src/core/iomgr/tcp_client_posix.c
@@ -48,6 +48,7 @@
 #include "src/core/iomgr/sockaddr_utils.h"
 #include "src/core/iomgr/socket_utils_posix.h"
 #include "src/core/iomgr/tcp_posix.h"
+#include "src/core/support/string.h"
 #include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
 #include <grpc/support/time.h>
@@ -185,6 +186,8 @@ void grpc_tcp_client_connect(void (*cb)(void *arg, grpc_endpoint *ep),
   async_connect *ac;
   struct sockaddr_in6 addr6_v4mapped;
   struct sockaddr_in addr4_copy;
+  char *name;
+  char *addr_str;
 
   /* Use dualstack sockets where available. */
   if (grpc_sockaddr_to_v4mapped(addr, &addr6_v4mapped)) {
@@ -211,24 +214,27 @@ void grpc_tcp_client_connect(void (*cb)(void *arg, grpc_endpoint *ep),
     err = connect(fd, addr, addr_len);
   } while (err < 0 && errno == EINTR);
 
+  grpc_sockaddr_to_string(&addr_str, addr, 1);
+  gpr_asprintf(&name, "tcp-client:%s", addr_str);
+
   if (err >= 0) {
     gpr_log(GPR_DEBUG, "instant connect");
-    cb(arg,
-       grpc_tcp_create(grpc_fd_create(fd), GRPC_TCP_DEFAULT_READ_SLICE_SIZE));
-    return;
+    cb(arg, grpc_tcp_create(grpc_fd_create(fd, name),
+                            GRPC_TCP_DEFAULT_READ_SLICE_SIZE));
+    goto done;
   }
 
   if (errno != EWOULDBLOCK && errno != EINPROGRESS) {
-    gpr_log(GPR_ERROR, "connect error: %s", strerror(errno));
+    gpr_log(GPR_ERROR, "connect error to '%s': %s", addr_str, strerror(errno));
     close(fd);
     cb(arg, NULL);
-    return;
+    goto done;
   }
 
   ac = gpr_malloc(sizeof(async_connect));
   ac->cb = cb;
   ac->cb_arg = arg;
-  ac->fd = grpc_fd_create(fd);
+  ac->fd = grpc_fd_create(fd, name);
   gpr_mu_init(&ac->mu);
   ac->refs = 2;
   ac->write_closure.cb = on_writable;
@@ -236,6 +242,10 @@ void grpc_tcp_client_connect(void (*cb)(void *arg, grpc_endpoint *ep),
 
   grpc_alarm_init(&ac->alarm, deadline, on_alarm, ac, gpr_now());
   grpc_fd_notify_on_write(ac->fd, &ac->write_closure);
+
+done:
+  gpr_free(name);
+  gpr_free(addr_str);
 }
 
 #endif
diff --git a/src/core/iomgr/tcp_server_posix.c b/src/core/iomgr/tcp_server_posix.c
index d1cd8a769c..3cd40faafc 100644
--- a/src/core/iomgr/tcp_server_posix.c
+++ b/src/core/iomgr/tcp_server_posix.c
@@ -60,6 +60,7 @@
 #include "src/core/iomgr/sockaddr_utils.h"
 #include "src/core/iomgr/socket_utils_posix.h"
 #include "src/core/iomgr/tcp_posix.h"
+#include "src/core/support/string.h"
 #include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
 #include <grpc/support/sync.h>
@@ -281,6 +282,8 @@ static void on_read(void *arg, int success) {
   for (;;) {
     struct sockaddr_storage addr;
     socklen_t addrlen = sizeof(addr);
+    char *addr_str;
+    char *name;
     /* Note: If we ever decide to return this address to the user, remember to
              strip off the ::ffff:0.0.0.0/96 prefix first. */
     int fd = grpc_accept4(sp->fd, (struct sockaddr *)&addr, &addrlen, 1, 1);
@@ -299,9 +302,15 @@ static void on_read(void *arg, int success) {
 
     grpc_set_socket_no_sigpipe_if_possible(fd);
 
-    sp->server->cb(
-        sp->server->cb_arg,
-        grpc_tcp_create(grpc_fd_create(fd), GRPC_TCP_DEFAULT_READ_SLICE_SIZE));
+    grpc_sockaddr_to_string(&addr_str, (struct sockaddr *)&addr, 1);
+    gpr_asprintf(&name, "tcp-server-connection:%s", addr_str);
+
+    sp->server->cb(sp->server->cb_arg,
+                   grpc_tcp_create(grpc_fd_create(fd, name),
+                                   GRPC_TCP_DEFAULT_READ_SLICE_SIZE));
+
+    gpr_free(addr_str);
+    gpr_free(name);
   }
 
   abort();
@@ -318,9 +327,13 @@ static int add_socket_to_server(grpc_tcp_server *s, int fd,
                                 const struct sockaddr *addr, int addr_len) {
   server_port *sp;
   int port;
+  char *addr_str;
+  char *name;
 
   port = prepare_socket(fd, addr, addr_len);
   if (port >= 0) {
+    grpc_sockaddr_to_string(&addr_str, (struct sockaddr *)&addr, 1);
+    gpr_asprintf(&name, "tcp-server-listener:%s", addr_str);
     gpr_mu_lock(&s->mu);
     GPR_ASSERT(!s->cb && "must add ports before starting server");
     /* append it to the list under a lock */
@@ -331,11 +344,13 @@ static int add_socket_to_server(grpc_tcp_server *s, int fd,
     sp = &s->ports[s->nports++];
     sp->server = s;
     sp->fd = fd;
-    sp->emfd = grpc_fd_create(fd);
+    sp->emfd = grpc_fd_create(fd, name);
     memcpy(sp->addr.untyped, addr, addr_len);
     sp->addr_len = addr_len;
     GPR_ASSERT(sp->emfd);
     gpr_mu_unlock(&s->mu);
+    gpr_free(addr_str);
+    gpr_free(name);
   }
 
   return port;