aio / timers: Convert aio_poll to use AioContext timers' deadline

Convert aio_poll to use deadline based on AioContext's timers.

aio_poll has been changed to return accurately whether progress
has occurred. Prior to this commit, aio_poll always returned
true if g_poll was entered, whether or not any progress was
made. This required a change to tests/test-aio.c where an
assert was backwards.

Signed-off-by: Alex Bligh <alex@alex.org.uk>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

aio-posix.c

@@ -165,6 +165,10 @@ static bool aio_dispatch(AioContext *ctx)
             g_free(tmp);
         }
     }
+
+    /* Run our timers */
+    progress |= timerlistgroup_run_timers(&ctx->tlg);
+
     return progress;
 }
 
@@ -219,9 +223,9 @@ bool aio_poll(AioContext *ctx, bool blocking)
     }
 
     /* wait until next event */
-    ret = g_poll((GPollFD *)ctx->pollfds->data,
-                 ctx->pollfds->len,
-                 blocking ? -1 : 0);
+    ret = qemu_poll_ns((GPollFD *)ctx->pollfds->data,
+                         ctx->pollfds->len,
+                         blocking ? timerlistgroup_deadline_ns(&ctx->tlg) : 0);
 
     /* if we have any readable fds, dispatch event */
     if (ret > 0) {
@@ -232,9 +236,11 @@ bool aio_poll(AioContext *ctx, bool blocking)
                 node->pfd.revents = pfd->revents;
             }
         }
-        if (aio_dispatch(ctx)) {
-            progress = true;
-        }
+    }
+
+    /* Run dispatch even if there were no readable fds to run timers */
+    if (aio_dispatch(ctx)) {
+        progress = true;
     }
 
     return progress;