[PATCH v9 09/25] tools/libx{l, c}: introduce should_checkpoint callback

[Wen Congyang <wency@cn.fujitsu.com>]

Under COLO, we are doing checkpoint on demand, if this
callback returns 1, we will take another checkpoint.
0 indicates unexpected error.

Signed-off-by: Yang Hongyang <hongyang.yang@easystack.cn>
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
---
 tools/libxc/include/xenguest.h     | 18 ++++++++++++++++++
 tools/libxl/libxl_save_msgs_gen.pl |  7 ++++---
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/tools/libxc/include/xenguest.h b/tools/libxc/include/xenguest.h
index bd133af..88d6e13 100644
--- a/tools/libxc/include/xenguest.h
+++ b/tools/libxc/include/xenguest.h
@@ -62,6 +62,15 @@ struct save_callbacks {
      * 1: take another checkpoint */
     int (*checkpoint)(void* data);
 
+    /*
+     * Called after the checkpoint callback.
+     *
+     * returns:
+     * 0: terminate checkpointing gracefully
+     * 1: take another checkpoint
+     */
+    int (*should_checkpoint)(void* data);
+
     /* Enable qemu-dm logging dirty pages to xen */
     int (*switch_qemu_logdirty)(int domid, unsigned enable, void *data); /* HVM only */
 
@@ -93,6 +102,15 @@ struct restore_callbacks {
 #define XGR_CHECKPOINT_FAILOVER 2 /* Failover and resume VM */
     int (*checkpoint)(void* data);
 
+    /*
+     * Called after the checkpoint callback.
+     *
+     * returns:
+     * 0: terminate checkpointing gracefully
+     * 1: take another checkpoint
+     */
+    int (*should_checkpoint)(void* data);
+
     /* to be provided as the last argument to each callback function */
     void* data;
 };
diff --git a/tools/libxl/libxl_save_msgs_gen.pl b/tools/libxl/libxl_save_msgs_gen.pl
index d6d2967..9107a86 100755
--- a/tools/libxl/libxl_save_msgs_gen.pl
+++ b/tools/libxl/libxl_save_msgs_gen.pl
@@ -26,11 +26,12 @@ our @msgs = (
     [  3, 'scxA',   "suspend", [] ],
     [  4, 'scxA',   "postcopy", [] ],
     [  5, 'srcxA',  "checkpoint", [] ],
-    [  6, 'scxA',   "switch_qemu_logdirty",  [qw(int domid
+    [  6, 'srcxA',  "should_checkpoint", [] ],
+    [  7, 'scxA',   "switch_qemu_logdirty",  [qw(int domid
                                               unsigned enable)] ],
-    [  7, 'r',      "restore_results",       ['unsigned long', 'store_mfn',
+    [  8, 'r',      "restore_results",       ['unsigned long', 'store_mfn',
                                               'unsigned long', 'console_mfn'] ],
-    [  8, 'srW',    "complete",              [qw(int retval
+    [  9, 'srW',    "complete",              [qw(int retval
                                                  int errnoval)] ],
 );
 
-- 
2.5.0