[V6,15/27] cpr: restart HMP interfaces

Commit Message

Steven Sistare Aug. 6, 2021, 9:43 p.m. UTC

cpr-save <filename> <mode>
  mode may be "restart"

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

Signed-off-by: Steve Sistare <[e-mail]>
---
 hmp-commands.hx       | 21 ++++++++++++++++++++-
 include/monitor/hmp.h |  1 +
 monitor/hmp-cmds.c    | 11 +++++++++++
 3 files changed, 32 insertions(+), 1 deletion(-)

Patch

diff --git a/hmp-commands.hx b/hmp-commands.hx
index 0a45c59..9541871 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -353,7 +353,7 @@  ERST
     {
         .name       = "cpr-save",
         .args_type  = "filename:s,mode:s",
-        .params     = "filename 'reboot'",
+        .params     = "filename 'reboot'|'restart'",
         .help       = "create a checkpoint of the VM in file",
         .cmd        = hmp_cpr_save,
     },
@@ -366,6 +366,25 @@  If *mode* is 'reboot', the checkpoint remains valid after a host kexec
 reboot, and guest ram must be backed by persistent shared memory.  To
 resume from the checkpoint, issue the quit command, reboot the system,
 and issue the cpr-load command.
+
+If *mode* is 'restart', the checkpoint remains valid after restarting qemu
+using a subsequent cpr-exec.  All guest RAM objects must be shared.  The
+share=on property is required for memory created with an explicit -object
+option, and the memfd-alloc machine property is required for memory that is
+implicitly created.  To resume from the checkpoint, issue the cpr-load command.
+ERST
+
+    {
+        .name       = "cpr-exec",
+        .args_type  = "command:S",
+        .params     = "command",
+        .help       = "Restart qemu by directly exec'ing command",
+        .cmd        = hmp_cpr_exec,
+    },
+
+SRST
+``cpr-exec`` *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 01b5df8..90f18fd 100644
--- a/include/monitor/hmp.h
+++ b/include/monitor/hmp.h
@@ -59,6 +59,7 @@  void hmp_loadvm(Monitor *mon, const QDict *qdict);
 void hmp_savevm(Monitor *mon, const QDict *qdict);
 void hmp_delvm(Monitor *mon, const QDict *qdict);
 void hmp_cpr_save(Monitor *mon, const QDict *qdict);
+void hmp_cpr_exec(Monitor *mon, const QDict *qdict);
 void hmp_cpr_load(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 da91a0a..99f75a1 100644
--- a/monitor/hmp-cmds.c
+++ b/monitor/hmp-cmds.c
@@ -1172,6 +1172,17 @@  out:
     hmp_handle_error(mon, err);
 }
 
+void hmp_cpr_exec(Monitor *mon, const QDict *qdict)
+{
+    Error *err = NULL;
+    const char *command = qdict_get_try_str(qdict, "command");
+    strList *args = strList_from_string(command, ' ');
+
+    qmp_cpr_exec(args, &err);
+    qapi_free_strList(args);
+    hmp_handle_error(mon, err);
+}
+
 void hmp_cpr_load(Monitor *mon, const QDict *qdict)
 {
     Error *err = NULL;