Re: [Qemu-devel] [PATCH 01/15] net/colo: Add notifier/callback related helpers for filter

[Hailiang Zhang]

On 2017/4/7 23:46, Dr. David Alan Gilbert wrote:

* zhanghailiang (zhang.zhanghaili...@huawei.com) wrote:

We will use this notifier to help COLO to notify filter object
to do something, like do checkpoint, or process failover event.

Cc: Jason Wang <jasow...@redhat.com>
Signed-off-by: zhanghailiang <zhang.zhanghaili...@huawei.com>
---
  net/colo.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  net/colo.h | 18 ++++++++++++
  2 files changed, 110 insertions(+)

<..>

+FilterNotifier *filter_noitifier_new(FilterNotifierCallback *cb,

                           ^^^^^^^^^ Typo - no*i*tifier

Good catch, will fix it in next version.

(I've not looked at this patch much, I'll leave networking stuff to Jason)

OK, thanks.

Dave

+                    void *opaque, Error **errp)
+{
+    FilterNotifier *notify;
+    int ret;
+
+    notify = (FilterNotifier *)g_source_new(&notifier_source_funcs,
+                sizeof(FilterNotifier));
+    ret = event_notifier_init(&notify->event, false);
+    if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to initialize event notifier");
+        goto fail;
+    }
+    notify->pfd.fd = event_notifier_get_fd(&notify->event);
+    notify->pfd.events = G_IO_IN | G_IO_HUP | G_IO_ERR;
+    notify->cb = cb;
+    notify->opaque = opaque;
+    g_source_add_poll(&notify->source, &notify->pfd);
+
+    return notify;
+
+fail:
+    g_source_destroy(&notify->source);
+    return NULL;
+}
+
+int filter_notifier_set(FilterNotifier *notify, uint64_t value)
+{
+    ssize_t ret;
+
+    do {
+        ret = write(notify->event.wfd, &value, sizeof(value));
+    } while (ret < 0 && errno == EINTR);
+
+    /* EAGAIN is fine, a read must be pending.  */
+    if (ret < 0 && errno != EAGAIN) {
+        return -errno;
+    }
+    return 0;
+}
diff --git a/net/colo.h b/net/colo.h
index cd9027f..00f03b5 100644
--- a/net/colo.h
+++ b/net/colo.h
@@ -19,6 +19,7 @@
  #include "qemu/jhash.h"
  #include "qemu/timer.h"
  #include "slirp/tcp.h"
+#include "qemu/event_notifier.h"

#define HASHTABLE_MAX_SIZE 16384 @@ -89,4 +90,21 @@ void connection_hashtable_reset(GHashTable *connection_track_table);

  Packet *packet_new(const void *data, int size);
  void packet_destroy(void *opaque, void *user_data);

+typedef void FilterNotifierCallback(void *opaque, int value);

+typedef struct FilterNotifier {
+    GSource source;
+    EventNotifier event;
+    GPollFD pfd;
+    FilterNotifierCallback *cb;
+    void *opaque;
+} FilterNotifier;
+
+FilterNotifier *filter_noitifier_new(FilterNotifierCallback *cb,
+                    void *opaque, Error **errp);
+int filter_notifier_set(FilterNotifier *notify, uint64_t value);
+
+enum {
+    COLO_CHECKPOINT = 2,
+    COLO_FAILOVER,
+};
  #endif /* QEMU_COLO_PROXY_H */
--
1.8.3.1

--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK

.