[PATCH v2 29/53] qapi: introduce x-query-registers QMP command

[Daniel P . Berrangé]

This is a counterpart to the HMP "info registers" command. It is being
added with an "x-" prefix because this QMP command is intended as an
ad hoc debugging tool and will thus not be modelled in QAPI as fully
structured data, nor will it have long term guaranteed stability.
The existing HMP command is rewritten to call the QMP command.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
 hw/core/machine-qmp-cmds.c | 30 ++++++++++++++++++++++++++++++
 monitor/misc.c             | 25 ++++++++++++++++---------
 qapi/common.json           | 11 +++++++++++
 qapi/machine.json          | 15 +++++++++++++++
 4 files changed, 72 insertions(+), 9 deletions(-)

diff --git a/hw/core/machine-qmp-cmds.c b/hw/core/machine-qmp-cmds.c
index 216fdfaf3a..c4e384f7d5 100644
--- a/hw/core/machine-qmp-cmds.c
+++ b/hw/core/machine-qmp-cmds.c
@@ -204,3 +204,33 @@ MemdevList *qmp_query_memdev(Error **errp)
     object_child_foreach(obj, query_memdev, &list);
     return list;
 }
+
+HumanReadableText *qmp_x_query_registers(bool has_cpu, int64_t cpu,
+                                         Error **errp)
+{
+    HumanReadableText *ret;
+    g_autoptr(GString) buf = g_string_new("");
+    CPUState *cs = NULL, *tmp;
+
+    if (has_cpu) {
+        CPU_FOREACH(tmp) {
+            if (cpu == tmp->cpu_index) {
+                cs = tmp;
+            }
+        }
+        if (!cs) {
+            error_setg(errp, "CPU %"PRId64" not available", cpu);
+            return NULL;
+        }
+        cpu_format_state(cs, buf, CPU_DUMP_FPU);
+    } else {
+        CPU_FOREACH(cs) {
+            g_string_append_printf(buf, "\nCPU#%d\n", cs->cpu_index);
+            cpu_format_state(cs, buf, CPU_DUMP_FPU);
+        }
+    }
+
+    ret = g_new0(HumanReadableText, 1);
+    ret->human_readable_text = g_steal_pointer(&buf->str);
+    return ret;
+}
diff --git a/monitor/misc.c b/monitor/misc.c
index ffe7966870..f25801a1a3 100644
--- a/monitor/misc.c
+++ b/monitor/misc.c
@@ -67,6 +67,7 @@
 #include "block/block-hmp-cmds.h"
 #include "qapi/qapi-commands-char.h"
 #include "qapi/qapi-commands-control.h"
+#include "qapi/qapi-commands-machine.h"
 #include "qapi/qapi-commands-migration.h"
 #include "qapi/qapi-commands-misc.h"
 #include "qapi/qapi-commands-qom.h"
@@ -301,23 +302,29 @@ int monitor_get_cpu_index(Monitor *mon)
 static void hmp_info_registers(Monitor *mon, const QDict *qdict)
 {
     bool all_cpus = qdict_get_try_bool(qdict, "cpustate_all", false);
-    CPUState *cs;
+    bool has_cpu = !all_cpus;
+    int64_t cpu = 0;
+    Error *err = NULL;
+    g_autoptr(HumanReadableText) info = NULL;
 
-    if (all_cpus) {
-        CPU_FOREACH(cs) {
-            monitor_printf(mon, "\nCPU#%d\n", cs->cpu_index);
-            cpu_dump_state(cs, NULL, CPU_DUMP_FPU);
-        }
-    } else {
-        cs = mon_get_cpu(mon);
+    if (has_cpu) {
+        CPUState *cs = mon_get_cpu(mon);
 
         if (!cs) {
             monitor_printf(mon, "No CPU available\n");
             return;
         }
 
-        cpu_dump_state(cs, NULL, CPU_DUMP_FPU);
+        cpu = cs->cpu_index;
     }
+
+    info = qmp_x_query_registers(has_cpu, cpu, &err);
+    if (err) {
+        error_report_err(err);
+        return;
+    }
+
+    monitor_printf(mon, "%s", info->human_readable_text);
 }
 
 static void hmp_info_sync_profile(Monitor *mon, const QDict *qdict)
diff --git a/qapi/common.json b/qapi/common.json
index 7c976296f0..de7614ca99 100644
--- a/qapi/common.json
+++ b/qapi/common.json
@@ -197,3 +197,14 @@
 { 'enum': 'GrabToggleKeys',
   'data': [ 'ctrl-ctrl', 'alt-alt', 'shift-shift','meta-meta', 'scrolllock',
             'ctrl-scrolllock' ] }
+
+##
+# @HumanReadableText:
+#
+# @human-readable-text: Formatted output intended for humans.
+#
+# Since: 6.2.0
+#
+##
+{ 'struct': 'HumanReadableText',
+  'data': { 'human-readable-text': 'str' } }
diff --git a/qapi/machine.json b/qapi/machine.json
index 157712f006..8737efa865 100644
--- a/qapi/machine.json
+++ b/qapi/machine.json
@@ -1312,3 +1312,18 @@
      '*cores': 'int',
      '*threads': 'int',
      '*maxcpus': 'int' } }
+
+##
+# @x-query-registers:
+#
+# @cpu: the CPU number to query. If omitted, queries all CPUs
+#
+# Query information on the CPU registers
+#
+# Returns: CPU state in an architecture-specific format
+#
+# Since: 6.2
+##
+{ 'command': 'x-query-registers',
+  'data': {'*cpu': 'int' },
+  'returns': 'HumanReadableText' }
-- 
2.31.1