[V4,13/25] cpr: HMP interfaces for restart

Commit Message

Steven Sistare July 6, 2021, 4:45 p.m. UTC

cprsave <file> <mode>
  mode may be "restart"

cprexec <command>
  Call cprexec().
  Arguments:
    command : command line to execute, with space-separated arguments

Signed-off-by: Steve Sistare <[e-mail]>
---
 hmp-commands.hx       | 20 +++++++++++++++++++-
 include/monitor/hmp.h |  1 +
 monitor/hmp-cmds.c    | 11 +++++++++++
 3 files changed, 31 insertions(+), 1 deletion(-)

Patch

diff --git a/hmp-commands.hx b/hmp-commands.hx
index 015faae..1066fe7 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -366,7 +366,7 @@  ERST
     {
         .name       = "cprsave",
         .args_type  = "file:s,mode:s",
-        .params     = "file 'reboot'",
+        .params     = "file 'restart'|'reboot'",
         .help       = "create a checkpoint of the VM in file",
         .cmd        = hmp_cprsave,
     },
@@ -379,6 +379,24 @@  If *mode* is 'reboot', the checkpoint remains valid after a host kexec
 reboot, and guest ram must be backed by persistant shared memory.  To
 resume from the checkpoint, issue the quit command, reboot the system,
 and issue the cprload command.
+
+If *mode* is 'restart', the checkpoint remains valid after restarting qemu,
+and guest ram must be allocated with the memfd-alloc machine option.  To
+resume from the checkpoint, issue the cprexec command to restart, and issue
+the cprload command.
+ERST
+
+    {
+        .name       = "cprexec",
+        .args_type  = "command:S",
+        .params     = "command",
+        .help       = "Restart qemu by directly exec'ing command",
+        .cmd        = hmp_cprexec,
+    },
+
+SRST
+``cprexec`` *command*
+Restart qemu by directly exec'ing *command*, replacing the qemu process.
 ERST
 
     {
diff --git a/include/monitor/hmp.h b/include/monitor/hmp.h
index e4ebdf1..c26d0d7 100644
--- a/include/monitor/hmp.h
+++ b/include/monitor/hmp.h
@@ -60,6 +60,7 @@  void hmp_savevm(Monitor *mon, const QDict *qdict);
 void hmp_delvm(Monitor *mon, const QDict *qdict);
 void hmp_cprinfo(Monitor *mon, const QDict *qdict);
 void hmp_cprsave(Monitor *mon, const QDict *qdict);
+void hmp_cprexec(Monitor *mon, const QDict *qdict);
 void hmp_cprload(Monitor *mon, const QDict *qdict);
 void hmp_migrate_cancel(Monitor *mon, const QDict *qdict);
 void hmp_migrate_continue(Monitor *mon, const QDict *qdict);
diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c
index f902dcf..adffe80 100644
--- a/monitor/hmp-cmds.c
+++ b/monitor/hmp-cmds.c
@@ -1213,6 +1213,17 @@  out:
     hmp_handle_error(mon, err);
 }
 
+void hmp_cprexec(Monitor *mon, const QDict *qdict)
+{
+    Error *err = NULL;
+    const char *command = qdict_get_try_str(qdict, "command");
+    strList *args = strList_from_string(command, ' ');
+
+    qmp_cprexec(args, &err);
+    qapi_free_strList(args);
+    hmp_handle_error(mon, err);
+}
+
 void hmp_cprload(Monitor *mon, const QDict *qdict)
 {
     Error *err = NULL;