replay: replay blockers for devices

Some devices are not supported by record/replay subsystem.
This patch introduces replay blocker which denies starting record/replay
if such devices are included into the configuration.

Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru>
Message-Id: <20150917162512.8676.11367.stgit@PASHA-ISP.def.inno>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>

hw/bt/hci.c

@@ -23,6 +23,8 @@
 #include "hw/usb.h"
 #include "sysemu/bt.h"
 #include "hw/bt.h"
+#include "qapi/qmp/qerror.h"
+#include "sysemu/replay.h"
 
 struct bt_hci_s {
     uint8_t *(*evt_packet)(void *opaque);
@@ -72,6 +74,8 @@ struct bt_hci_s {
 
     struct HCIInfo info;
     struct bt_device_s device;
+
+    Error *replay_blocker;
 };
 
 #define DEFAULT_RSSI_DBM	20
@@ -2189,6 +2193,9 @@ struct HCIInfo *bt_new_hci(struct bt_scatternet_s *net)
 
     s->device.handle_destroy = bt_hci_destroy;
 
+    error_setg(&s->replay_blocker, QERR_REPLAY_NOT_SUPPORTED, "-bt hci");
+    replay_add_blocker(s->replay_blocker);
+
     return &s->info;
 }
 

include/qapi/qmp/qerror.h

@@ -106,4 +106,7 @@
 #define QERR_UNSUPPORTED \
     "this feature or command is not currently supported"
 
+#define QERR_REPLAY_NOT_SUPPORTED \
+    "Record/replay feature is not supported for '%s'"
+
 #endif /* QERROR_H */

include/sysemu/replay.h

@@ -15,6 +15,7 @@
 #include <stdbool.h>
 #include <stdint.h>
 #include "qapi-types.h"
+#include "qapi/error.h"
 #include "qemu/typedefs.h"
 
 /* replay clock kinds */
@@ -51,6 +52,8 @@ void replay_configure(struct QemuOpts *opts);
 void replay_start(void);
 /*! Closes replay log file and frees other resources. */
 void replay_finish(void);
+/*! Adds replay blocker with the specified error description */
+void replay_add_blocker(Error *reason);
 
 /* Processing the instructions */
 

replay/replay.c

@@ -28,6 +28,7 @@ ReplayMode replay_mode = REPLAY_MODE_NONE;
 /* Name of replay file  */
 static char *replay_filename;
 ReplayState replay_state;
+static GSList *replay_blockers;
 
 bool replay_next_event_is(int event)
 {
@@ -289,6 +290,12 @@ void replay_start(void)
         return;
     }
 
+    if (replay_blockers) {
+        error_report("Record/replay: %s",
+                     error_get_pretty(replay_blockers->data));
+        exit(1);
+    }
+
     /* Timer for snapshotting will be set up here. */
 
     replay_enable_events();
@@ -324,3 +331,8 @@ void replay_finish(void)
     replay_finish_events();
     replay_mutex_destroy();
 }
+
+void replay_add_blocker(Error *reason)
+{
+    replay_blockers = g_slist_prepend(replay_blockers, reason);
+}

vl.c

@@ -123,6 +123,7 @@ int main(int argc, char **argv)
 #include "exec/semihost.h"
 #include "crypto/init.h"
 #include "sysemu/replay.h"
+#include "qapi/qmp/qerror.h"
 
 #define MAX_VIRTIO_CONSOLES 1
 #define MAX_SCLP_CONSOLES 1
@@ -847,7 +848,11 @@ static void configure_rtc(QemuOpts *opts)
         if (!strcmp(value, "utc")) {
             rtc_utc = 1;
         } else if (!strcmp(value, "localtime")) {
+            Error *blocker = NULL;
             rtc_utc = 0;
+            error_setg(&blocker, QERR_REPLAY_NOT_SUPPORTED,
+                      "-rtc base=localtime");
+            replay_add_blocker(blocker);
         } else {
             configure_rtc_date_offset(value, 0);
         }
@@ -1256,6 +1261,11 @@ static void smp_parse(QemuOpts *opts)
         exit(1);
     }
 
+    if (smp_cpus > 1 || smp_cores > 1 || smp_threads > 1) {
+        Error *blocker = NULL;
+        error_setg(&blocker, QERR_REPLAY_NOT_SUPPORTED, "smp");
+        replay_add_blocker(blocker);
+    }
 }
 
 static void realtime_init(void)