Resolved merge conflicts

1 files changed, 41 insertions, 46 deletions

diff --git a/src/core/iomgr/fd_posix.c b/src/core/iomgr/fd_posix.c
index 4f52339bc1..41fd24e05a 100644
--- a/src/core/iomgr/fd_posix.c
+++ b/src/core/iomgr/fd_posix.c
@@ -45,7 +45,10 @@
 #include <grpc/support/log.h>
 #include <grpc/support/useful.h>
 
-enum descriptor_state { NOT_READY, READY, WAITING };
+enum descriptor_state {
+  NOT_READY = 0,
+  READY = 1
+}; /* or a pointer to a closure to call */
 
 /* We need to keep a freelist not because of any concerns of malloc performance
  * but instead so that implementations with multiple threads in (for example)
@@ -88,8 +91,8 @@ static grpc_fd *alloc_fd(int fd) {
     gpr_mu_init(&r->watcher_mu);
   }
   gpr_atm_rel_store(&r->refst, 1);
-  gpr_atm_rel_store(&r->readst.state, NOT_READY);
-  gpr_atm_rel_store(&r->writest.state, NOT_READY);
+  gpr_atm_rel_store(&r->readst, NOT_READY);
+  gpr_atm_rel_store(&r->writest, NOT_READY);
   gpr_atm_rel_store(&r->shutdown, 0);
   r->fd = fd;
   r->watcher_root.next = r->watcher_root.prev = &r->watcher_root;
@@ -166,11 +169,6 @@ void grpc_fd_ref(grpc_fd *fd) { ref_by(fd, 2); }
 
 void grpc_fd_unref(grpc_fd *fd) { unref_by(fd, 2); }
 
-typedef struct {
-  grpc_iomgr_cb_func cb;
-  void *arg;
-} callback;
-
 static void make_callback(grpc_iomgr_cb_func cb, void *arg, int success,
                           int allow_synchronous_callback) {
   if (allow_synchronous_callback) {
@@ -180,18 +178,18 @@ static void make_callback(grpc_iomgr_cb_func cb, void *arg, int success,
   }
 }
 
-static void make_callbacks(callback *callbacks, size_t n, int success,
+static void make_callbacks(grpc_iomgr_closure *callbacks, size_t n, int success,
                            int allow_synchronous_callback) {
   size_t i;
   for (i = 0; i < n; i++) {
-    make_callback(callbacks[i].cb, callbacks[i].arg, success,
+    make_callback(callbacks[i].cb, callbacks[i].cb_arg, success,
                   allow_synchronous_callback);
   }
 }
 
-static void notify_on(grpc_fd *fd, grpc_fd_state *st, grpc_iomgr_cb_func cb,
-                      void *arg, int allow_synchronous_callback) {
-  switch ((enum descriptor_state)gpr_atm_acq_load(&st->state)) {
+static void notify_on(grpc_fd *fd, gpr_atm *st, grpc_iomgr_closure *closure,
+                      int allow_synchronous_callback) {
+  switch (gpr_atm_acq_load(st)) {
     case NOT_READY:
       /* There is no race if the descriptor is already ready, so we skip
          the interlocked op in that case.  As long as the app doesn't
@@ -199,9 +197,7 @@ static void notify_on(grpc_fd *fd, grpc_fd_state *st, grpc_iomgr_cb_func cb,
          oldval should never be anything other than READY or NOT_READY.  We
          don't
          check for user error on the fast path. */
-      st->cb = cb;
-      st->cb_arg = arg;
-      if (gpr_atm_rel_cas(&st->state, NOT_READY, WAITING)) {
+      if (gpr_atm_rel_cas(st, NOT_READY, (gpr_intptr)closure)) {
         /* swap was successful -- the closure will run after the next
            set_ready call.  NOTE: we don't have an ABA problem here,
            since we should never have concurrent calls to the same
@@ -212,12 +208,13 @@ static void notify_on(grpc_fd *fd, grpc_fd_state *st, grpc_iomgr_cb_func cb,
     /* swap was unsuccessful due to an intervening set_ready call.
        Fall through to the READY code below */
     case READY:
-      assert(gpr_atm_acq_load(&st->state) == READY);
-      gpr_atm_rel_store(&st->state, NOT_READY);
-      make_callback(cb, arg, !gpr_atm_acq_load(&fd->shutdown),
+      assert(gpr_atm_acq_load(st) == READY);
+      gpr_atm_rel_store(st, NOT_READY);
+      make_callback(closure->cb, closure->cb_arg,
+                    !gpr_atm_acq_load(&fd->shutdown),
                     allow_synchronous_callback);
       return;
-    case WAITING:
+    default: /* WAITING */
       /* upcallptr was set to a different closure.  This is an error! */
       gpr_log(GPR_ERROR,
               "User called a notify_on function with a previous callback still "
@@ -228,38 +225,38 @@ static void notify_on(grpc_fd *fd, grpc_fd_state *st, grpc_iomgr_cb_func cb,
   abort();
 }
 
-static void set_ready_locked(grpc_fd_state *st, callback *callbacks,
+static void set_ready_locked(gpr_atm *st, grpc_iomgr_closure *callbacks,
                              size_t *ncallbacks) {
-  callback *c;
+  gpr_intptr state = gpr_atm_acq_load(st);
 
-  switch ((enum descriptor_state)gpr_atm_acq_load(&st->state)) {
+  switch (state) {
+    case READY:
+      /* duplicate ready, ignore */
+      return;
     case NOT_READY:
-      if (gpr_atm_rel_cas(&st->state, NOT_READY, READY)) {
+      if (gpr_atm_rel_cas(st, NOT_READY, READY)) {
         /* swap was successful -- the closure will run after the next
            notify_on call. */
         return;
       }
-    /* swap was unsuccessful due to an intervening set_ready call.
-       Fall through to the WAITING code below */
-    case WAITING:
-      assert(gpr_atm_acq_load(&st->state) == WAITING);
-      c = &callbacks[(*ncallbacks)++];
-      c->cb = st->cb;
-      c->arg = st->cb_arg;
-      gpr_atm_rel_store(&st->state, NOT_READY);
-      return;
-    case READY:
-      /* duplicate ready, ignore */
+      /* swap was unsuccessful due to an intervening set_ready call.
+         Fall through to the WAITING code below */
+      state = gpr_atm_acq_load(st);
+    default: /* waiting */
+      assert(gpr_atm_acq_load(st) != READY &&
+             gpr_atm_acq_load(st) != NOT_READY);
+      callbacks[(*ncallbacks)++] = *(grpc_iomgr_closure *)state;
+      gpr_atm_rel_store(st, NOT_READY);
       return;
   }
 }
 
-static void set_ready(grpc_fd *fd, grpc_fd_state *st,
+static void set_ready(grpc_fd *fd, gpr_atm *st,
                       int allow_synchronous_callback) {
   /* only one set_ready can be active at once (but there may be a racing
      notify_on) */
   int success;
-  callback cb;
+  grpc_iomgr_closure cb;
   size_t ncb = 0;
   gpr_mu_lock(&fd->set_state_mu);
   set_ready_locked(st, &cb, &ncb);
@@ -269,7 +266,7 @@ static void set_ready(grpc_fd *fd, grpc_fd_state *st,
 }
 
 void grpc_fd_shutdown(grpc_fd *fd) {
-  callback cb[2];
+  grpc_iomgr_closure cb[2];
   size_t ncb = 0;
   gpr_mu_lock(&fd->set_state_mu);
   GPR_ASSERT(!gpr_atm_acq_load(&fd->shutdown));
@@ -280,14 +277,12 @@ void grpc_fd_shutdown(grpc_fd *fd) {
   make_callbacks(cb, ncb, 0, 0);
 }
 
-void grpc_fd_notify_on_read(grpc_fd *fd, grpc_iomgr_cb_func read_cb,
-                            void *read_cb_arg) {
-  notify_on(fd, &fd->readst, read_cb, read_cb_arg, 0);
+void grpc_fd_notify_on_read(grpc_fd *fd, grpc_iomgr_closure *closure) {
+  notify_on(fd, &fd->readst, closure, 0);
 }
 
-void grpc_fd_notify_on_write(grpc_fd *fd, grpc_iomgr_cb_func write_cb,
-                             void *write_cb_arg) {
-  notify_on(fd, &fd->writest, write_cb, write_cb_arg, 0);
+void grpc_fd_notify_on_write(grpc_fd *fd, grpc_iomgr_closure *closure) {
+  notify_on(fd, &fd->writest, closure, 0);
 }
 
 gpr_uint32 grpc_fd_begin_poll(grpc_fd *fd, grpc_pollset *pollset,
@@ -305,8 +300,8 @@ gpr_uint32 grpc_fd_begin_poll(grpc_fd *fd, grpc_pollset *pollset,
   watcher->fd = fd;
   gpr_mu_unlock(&fd->watcher_mu);
 
-  return (gpr_atm_acq_load(&fd->readst.state) != READY ? read_mask : 0) |
-         (gpr_atm_acq_load(&fd->writest.state) != READY ? write_mask : 0);
+  return (gpr_atm_acq_load(&fd->readst) != READY ? read_mask : 0) |
+         (gpr_atm_acq_load(&fd->writest) != READY ? write_mask : 0);
 }
 
 void grpc_fd_end_poll(grpc_fd_watcher *watcher) {