Merge pull request #7615 from rjshade/rewrite_udp_server_linked_list

Rewrite udp server linked list

2 files changed, 67 insertions, 48 deletions

diff --git a/src/core/lib/iomgr/udp_server.c b/src/core/lib/iomgr/udp_server.c
index edf7b133e9..20eae7cbdd 100644
--- a/src/core/lib/iomgr/udp_server.c
+++ b/src/core/lib/iomgr/udp_server.c
@@ -64,12 +64,12 @@
 #include "src/core/lib/iomgr/resolve_address.h"
 #include "src/core/lib/iomgr/sockaddr_utils.h"
 #include "src/core/lib/iomgr/socket_utils_posix.h"
+#include "src/core/lib/iomgr/unix_sockets_posix.h"
 #include "src/core/lib/support/string.h"
 
-#define INIT_PORT_CAP 2
-
 /* one listening port */
-typedef struct {
+typedef struct grpc_udp_listener grpc_udp_listener;
+struct grpc_udp_listener {
   int fd;
   grpc_fd *emfd;
   grpc_udp_server *server;
@@ -82,12 +82,13 @@ typedef struct {
   grpc_closure destroyed_closure;
   grpc_udp_server_read_cb read_cb;
   grpc_udp_server_orphan_cb orphan_cb;
-} server_port;
+
+  struct grpc_udp_listener *next;
+};
 
 /* the overall server */
 struct grpc_udp_server {
   gpr_mu mu;
-  gpr_cv cv;
 
   /* active port count: how many ports are actually still listening */
   size_t active_ports;
@@ -97,10 +98,10 @@ struct grpc_udp_server {
   /* is this server shutting down? (boolean) */
   int shutdown;
 
-  /* all listening ports */
-  server_port *ports;
-  size_t nports;
-  size_t port_capacity;
+  /* linked list of server ports */
+  grpc_udp_listener *head;
+  grpc_udp_listener *tail;
+  unsigned nports;
 
   /* shutdown callback */
   grpc_closure *shutdown_complete;
@@ -116,24 +117,29 @@ struct grpc_udp_server {
 grpc_udp_server *grpc_udp_server_create(void) {
   grpc_udp_server *s = gpr_malloc(sizeof(grpc_udp_server));
   gpr_mu_init(&s->mu);
-  gpr_cv_init(&s->cv);
   s->active_ports = 0;
   s->destroyed_ports = 0;
   s->shutdown = 0;
-  s->ports = gpr_malloc(sizeof(server_port) * INIT_PORT_CAP);
+  s->head = NULL;
+  s->tail = NULL;
   s->nports = 0;
-  s->port_capacity = INIT_PORT_CAP;
 
   return s;
 }
 
 static void finish_shutdown(grpc_exec_ctx *exec_ctx, grpc_udp_server *s) {
-  grpc_exec_ctx_sched(exec_ctx, s->shutdown_complete, GRPC_ERROR_NONE, NULL);
+  if (s->shutdown_complete != NULL) {
+    grpc_exec_ctx_sched(exec_ctx, s->shutdown_complete, GRPC_ERROR_NONE, NULL);
+  }
 
   gpr_mu_destroy(&s->mu);
-  gpr_cv_destroy(&s->cv);
 
-  gpr_free(s->ports);
+  while (s->head) {
+    grpc_udp_listener *sp = s->head;
+    s->head = sp->next;
+    gpr_free(sp);
+  }
+
   gpr_free(s);
 }
 
@@ -154,8 +160,6 @@ static void destroyed_port(grpc_exec_ctx *exec_ctx, void *server,
    events will be received on them - at this point it's safe to destroy
    things */
 static void deactivated_all_ports(grpc_exec_ctx *exec_ctx, grpc_udp_server *s) {
-  size_t i;
-
   /* delete ALL the things */
   gpr_mu_lock(&s->mu);
 
@@ -164,9 +168,11 @@ static void deactivated_all_ports(grpc_exec_ctx *exec_ctx, grpc_udp_server *s) {
     return;
   }
 
-  if (s->nports) {
-    for (i = 0; i < s->nports; i++) {
-      server_port *sp = &s->ports[i];
+  if (s->head) {
+    grpc_udp_listener *sp;
+    for (sp = s->head; sp; sp = sp->next) {
+      grpc_unlink_if_unix_domain_socket(&sp->addr.sockaddr);
+
       sp->destroyed_closure.cb = destroyed_port;
       sp->destroyed_closure.cb_arg = s;
 
@@ -187,7 +193,7 @@ static void deactivated_all_ports(grpc_exec_ctx *exec_ctx, grpc_udp_server *s) {
 
 void grpc_udp_server_destroy(grpc_exec_ctx *exec_ctx, grpc_udp_server *s,
                              grpc_closure *on_done) {
-  size_t i;
+  grpc_udp_listener *sp;
   gpr_mu_lock(&s->mu);
 
   GPR_ASSERT(!s->shutdown);
@@ -197,14 +203,10 @@ void grpc_udp_server_destroy(grpc_exec_ctx *exec_ctx, grpc_udp_server *s,
 
   /* shutdown all fd's */
   if (s->active_ports) {
-    for (i = 0; i < s->nports; i++) {
-      server_port *sp = &s->ports[i];
-      /* Call the orphan_cb to signal that the FD is about to be closed and
-       * should no longer be used. */
+    for (sp = s->head; sp; sp = sp->next) {
       GPR_ASSERT(sp->orphan_cb);
       sp->orphan_cb(sp->emfd);
-
-      grpc_fd_shutdown(exec_ctx, s->ports[i].emfd);
+      grpc_fd_shutdown(exec_ctx, sp->emfd);
     }
     gpr_mu_unlock(&s->mu);
   } else {
@@ -281,10 +283,10 @@ error:
 
 /* event manager callback when reads are ready */
 static void on_read(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
-  server_port *sp = arg;
+  grpc_udp_listener *sp = arg;
 
+  gpr_mu_lock(&sp->server->mu);
   if (error != GRPC_ERROR_NONE) {
-    gpr_mu_lock(&sp->server->mu);
     if (0 == --sp->server->active_ports) {
       gpr_mu_unlock(&sp->server->mu);
       deactivated_all_ports(exec_ctx, sp->server);
@@ -300,13 +302,14 @@ static void on_read(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
 
   /* Re-arm the notification event so we get another chance to read. */
   grpc_fd_notify_on_read(exec_ctx, sp->emfd, &sp->read_closure);
+  gpr_mu_unlock(&sp->server->mu);
 }
 
 static int add_socket_to_server(grpc_udp_server *s, int fd,
                                 const struct sockaddr *addr, size_t addr_len,
                                 grpc_udp_server_read_cb read_cb,
                                 grpc_udp_server_orphan_cb orphan_cb) {
-  server_port *sp;
+  grpc_udp_listener *sp;
   int port;
   char *addr_str;
   char *name;
@@ -317,12 +320,15 @@ static int add_socket_to_server(grpc_udp_server *s, int fd,
     gpr_asprintf(&name, "udp-server-listener:%s", addr_str);
     gpr_free(addr_str);
     gpr_mu_lock(&s->mu);
-    /* append it to the list under a lock */
-    if (s->nports == s->port_capacity) {
-      s->port_capacity *= 2;
-      s->ports = gpr_realloc(s->ports, sizeof(server_port) * s->port_capacity);
+    s->nports++;
+    sp = gpr_malloc(sizeof(grpc_udp_listener));
+    sp->next = NULL;
+    if (s->head == NULL) {
+      s->head = sp;
+    } else {
+      s->tail->next = sp;
     }
-    sp = &s->ports[s->nports++];
+    s->tail = sp;
     sp->server = s;
     sp->fd = fd;
     sp->emfd = grpc_fd_create(fd, name);
@@ -341,9 +347,9 @@ static int add_socket_to_server(grpc_udp_server *s, int fd,
 int grpc_udp_server_add_port(grpc_udp_server *s, const void *addr,
                              size_t addr_len, grpc_udp_server_read_cb read_cb,
                              grpc_udp_server_orphan_cb orphan_cb) {
+  grpc_udp_listener *sp;
   int allocated_port1 = -1;
   int allocated_port2 = -1;
-  unsigned i;
   int fd;
   grpc_dualstack_mode dsmode;
   struct sockaddr_in6 addr6_v4mapped;
@@ -358,9 +364,9 @@ int grpc_udp_server_add_port(grpc_udp_server *s, const void *addr,
   /* Check if this is a wildcard port, and if so, try to keep the port the same
      as some previously created listener. */
   if (grpc_sockaddr_get_port(addr) == 0) {
-    for (i = 0; i < s->nports; i++) {
+    for (sp = s->head; sp; sp = sp->next) {
       sockname_len = sizeof(sockname_temp);
-      if (0 == getsockname(s->ports[i].fd, (struct sockaddr *)&sockname_temp,
+      if (0 == getsockname(sp->fd, (struct sockaddr *)&sockname_temp,
                            &sockname_len)) {
         port = grpc_sockaddr_get_port((struct sockaddr *)&sockname_temp);
         if (port > 0) {
@@ -421,27 +427,40 @@ done:
 }
 
 int grpc_udp_server_get_fd(grpc_udp_server *s, unsigned port_index) {
-  return (port_index < s->nports) ? s->ports[port_index].fd : -1;
+  grpc_udp_listener *sp;
+  if (port_index >= s->nports) {
+    return -1;
+  }
+
+  for (sp = s->head; sp && port_index != 0; sp = sp->next) {
+    --port_index;
+  }
+  return sp->fd;
 }
 
 void grpc_udp_server_start(grpc_exec_ctx *exec_ctx, grpc_udp_server *s,
                            grpc_pollset **pollsets, size_t pollset_count,
                            grpc_server *server) {
-  size_t i, j;
+  size_t i;
   gpr_mu_lock(&s->mu);
+  grpc_udp_listener *sp;
   GPR_ASSERT(s->active_ports == 0);
   s->pollsets = pollsets;
   s->grpc_server = server;
-  for (i = 0; i < s->nports; i++) {
-    for (j = 0; j < pollset_count; j++) {
-      grpc_pollset_add_fd(exec_ctx, pollsets[j], s->ports[i].emfd);
+
+  sp = s->head;
+  while (sp != NULL) {
+    for (i = 0; i < pollset_count; i++) {
+      grpc_pollset_add_fd(exec_ctx, pollsets[i], sp->emfd);
     }
-    s->ports[i].read_closure.cb = on_read;
-    s->ports[i].read_closure.cb_arg = &s->ports[i];
-    grpc_fd_notify_on_read(exec_ctx, s->ports[i].emfd,
-                           &s->ports[i].read_closure);
+    sp->read_closure.cb = on_read;
+    sp->read_closure.cb_arg = sp;
+    grpc_fd_notify_on_read(exec_ctx, sp->emfd, &sp->read_closure);
+
     s->active_ports++;
+    sp = sp->next;
   }
+
   gpr_mu_unlock(&s->mu);
 }
 
diff --git a/src/core/lib/iomgr/udp_server.h b/src/core/lib/iomgr/udp_server.h
index 33c5ce11cd..70d0f19454 100644
--- a/src/core/lib/iomgr/udp_server.h
+++ b/src/core/lib/iomgr/udp_server.h
@@ -59,7 +59,7 @@ void grpc_udp_server_start(grpc_exec_ctx *exec_ctx, grpc_udp_server *udp_server,
                            grpc_pollset **pollsets, size_t pollset_count,
                            struct grpc_server *server);
 
-int grpc_udp_server_get_fd(grpc_udp_server *s, unsigned index);
+int grpc_udp_server_get_fd(grpc_udp_server *s, unsigned port_index);
 
 /* Add a port to the server, returning port number on success, or negative
    on failure.