From 7e6246670add62116729bd93811e41eb60f66b77 Mon Sep 17 00:00:00 2001
From: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Date: Wed, 18 Jan 2012 14:40:40 +0000
Subject: [PATCH] coroutine: add co_sleep_ns() coroutine sleep function
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
Makefile.objs | 1 +
qemu-coroutine-sleep.c | 38 ++++++++++++++++++++++++++++++++++++++
qemu-coroutine.h | 9 +++++++++
3 files changed, 48 insertions(+)
create mode 100644 qemu-coroutine-sleep.c
diff --git a/Makefile.objs b/Makefile.objs
index 9ca606356f..48d14777a0 100644
--- a/Makefile.objs
+++ b/Makefile.objs
@@ -13,6 +13,7 @@ oslib-obj-$(CONFIG_POSIX) += oslib-posix.o qemu-thread-posix.o
#######################################################################
# coroutines
coroutine-obj-y = qemu-coroutine.o qemu-coroutine-lock.o qemu-coroutine-io.o
+coroutine-obj-y += qemu-coroutine-sleep.o
ifeq ($(CONFIG_UCONTEXT_COROUTINE),y)
coroutine-obj-$(CONFIG_POSIX) += coroutine-ucontext.o
else
diff --git a/qemu-coroutine-sleep.c b/qemu-coroutine-sleep.c
new file mode 100644
index 0000000000..fd65274446
--- /dev/null
+++ b/qemu-coroutine-sleep.c
@@ -0,0 +1,38 @@
+/*
+ * QEMU coroutine sleep
+ *
+ * Copyright IBM, Corp. 2011
+ *
+ * Authors:
+ * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2 or later.
+ * See the COPYING.LIB file in the top-level directory.
+ *
+ */
+
+#include "qemu-coroutine.h"
+#include "qemu-timer.h"
+
+typedef struct CoSleepCB {
+ QEMUTimer *ts;
+ Coroutine *co;
+} CoSleepCB;
+
+static void co_sleep_cb(void *opaque)
+{
+ CoSleepCB *sleep_cb = opaque;
+
+ qemu_free_timer(sleep_cb->ts);
+ qemu_coroutine_enter(sleep_cb->co, NULL);
+}
+
+void coroutine_fn co_sleep_ns(QEMUClock *clock, int64_t ns)
+{
+ CoSleepCB sleep_cb = {
+ .co = qemu_coroutine_self(),
+ };
+ sleep_cb.ts = qemu_new_timer(clock, SCALE_NS, co_sleep_cb, &sleep_cb);
+ qemu_mod_timer(sleep_cb.ts, qemu_get_clock_ns(clock) + ns);
+ qemu_coroutine_yield();
+}
diff --git a/qemu-coroutine.h b/qemu-coroutine.h
index 8a55fe125e..34c15d4116 100644
--- a/qemu-coroutine.h
+++ b/qemu-coroutine.h
@@ -17,6 +17,7 @@
#include <stdbool.h>
#include "qemu-queue.h"
+#include "qemu-timer.h"
/**
* Coroutines are a mechanism for stack switching and can be used for
@@ -199,4 +200,12 @@ void qemu_co_rwlock_wrlock(CoRwlock *lock);
*/
void qemu_co_rwlock_unlock(CoRwlock *lock);
+/**
+ * Yield the coroutine for a given duration
+ *
+ * Note this function uses timers and hence only works when a main loop is in
+ * use. See main-loop.h and do not use from qemu-tool programs.
+ */
+void coroutine_fn co_sleep_ns(QEMUClock *clock, int64_t ns);
+
#endif /* QEMU_COROUTINE_H */