[RFC PATCH 2/9] plugins/api: Expose virtual clock timers to plugins

[Ruslan Ruslichenko <ruslichenko.r@gmail.com>]

From: Ruslan Ruslichenko <Ruslan_Ruslichenko@epam.com>

This patch extends QEMU Plugins API to allow set timers
in guest's virtual clock (QEMU_CLOCK_VIRTUAL).

It introduces qemu_plugin_timer_virt_ns(), which allows
scheduling a one-shot callback.

The patch also adds qemu_plugin_get_virtual_clock_ns(),
which can be used to query the current virtual time.

Signed-off-by: Ruslan Ruslichenko <Ruslan_Ruslichenko@epam.com>
---
 include/plugins/qemu-plugin.h |  6 ++++++
 plugins/api.c                 | 29 +++++++++++++++++++++++++++++
 2 files changed, 35 insertions(+)

diff --git a/include/plugins/qemu-plugin.h b/include/plugins/qemu-plugin.h
index 17a834dca9..bbd21e79c5 100644
--- a/include/plugins/qemu-plugin.h
+++ b/include/plugins/qemu-plugin.h
@@ -1246,6 +1246,12 @@ void qemu_plugin_u64_set(qemu_plugin_u64 entry, unsigned int vcpu_index,
 QEMU_PLUGIN_API
 uint64_t qemu_plugin_u64_sum(qemu_plugin_u64 entry);
 
+QEMU_PLUGIN_API
+uint64_t qemu_plugin_get_virtual_clock_ns(void);
+
+QEMU_PLUGIN_API
+void qemu_plugin_timer_virt_ns(uint64_t time, void (*cb)(void*), void *opaque);
+
 #ifdef __cplusplus
 } /* extern "C" */
 #endif
diff --git a/plugins/api.c b/plugins/api.c
index 04ca7da7f1..609ea69293 100644
--- a/plugins/api.c
+++ b/plugins/api.c
@@ -39,6 +39,7 @@
 #include "qemu/main-loop.h"
 #include "qemu/plugin.h"
 #include "qemu/log.h"
+#include "qemu/timer.h"
 #include "system/memory.h"
 #include "tcg/tcg.h"
 #include "exec/gdbstub.h"
@@ -652,3 +653,31 @@ uint64_t qemu_plugin_u64_sum(qemu_plugin_u64 entry)
     return total;
 }
 
+typedef struct {
+    void (*cb)(void *opaque);
+    void* opaque;
+    QEMUTimer *timer;
+} qemu_plugin_timer_data;
+
+static void timer_cb(void* opaque)
+{
+    qemu_plugin_timer_data *data = (qemu_plugin_timer_data*)opaque;
+
+    data->cb(data->opaque);
+
+    timer_free(data->timer);
+    g_free(data);
+}
+
+QEMU_PLUGIN_API
+void qemu_plugin_timer_virt_ns(uint64_t time, void (*cb)(void*), void *opaque)
+{
+    qemu_plugin_timer_data* data = g_new0(qemu_plugin_timer_data, 1);
+
+    data->cb = cb;
+    data->opaque = opaque;
+
+    data->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, timer_cb, data);
+
+    timer_mod(data->timer, time);
+}
-- 
2.43.0