From: Pavel Dovgalyuk <pavel.dovga...@ispras.ru>
This patch adds hmp/qmp commands replay_seek/replay-seek that proceed
the execution to the specified instruction count.
The command automatically loads nearest snapshot and replays the execution
to find the desired instruction count.
Signed-off-by: Pavel Dovgalyuk <pavel.dovga...@ispras.ru>
Acked-by: Markus Armbruster <arm...@redhat.com>
--
v2:
- renamed replay_seek qmp command into replay-seek
(suggested by Eric Blake)
v7:
- small fixes related to Markus Armbruster's review
v9:
- changed 'step' parameter name to 'icount'
- moved json stuff to replay.json and updated the description
(suggested by Markus Armbruster)
v10:
- updated the descriptions
---
hmp-commands.hx | 19 +++++++++
include/monitor/hmp.h | 1
qapi/replay.json | 20 ++++++++++
replay/replay-debugging.c | 92 +++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 132 insertions(+)
diff --git a/hmp-commands.hx b/hmp-commands.hx
index 3704294da8..420565c7f8 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -1964,6 +1964,25 @@ STEXI
@findex replay_delete_break
Remove replay breakpoint which was previously set with replay_break.
The command is ignored when there are no replay breakpoints.
+ETEXI
+
+ {
+ .name = "replay_seek",
+ .args_type = "icount:i",
+ .params = "icount",
+ .help = "replay execution to the specified instruction count",
+ .cmd = hmp_replay_seek,
+ },
+
+STEXI
+@item replay_seek @var{icount}
+@findex replay_seek
+Automatically proceed to the instruction count @var{icount}, when
+replaying the execution. The command automatically loads nearest
+snapshot and replays the execution to find the desired instruction.
+When there is no preceding snapshot or the execution is not replayed,
+then the command fails.
+icount for the reference may be observed with 'info replay' command.
ETEXI
{
diff --git a/include/monitor/hmp.h b/include/monitor/hmp.h
index 0fd477aa13..bd97d4a8c6 100644
--- a/include/monitor/hmp.h
+++ b/include/monitor/hmp.h
@@ -156,5 +156,6 @@ void hmp_info_sev(Monitor *mon, const QDict *qdict);
void hmp_info_replay(Monitor *mon, const QDict *qdict);
void hmp_replay_break(Monitor *mon, const QDict *qdict);
void hmp_replay_delete_break(Monitor *mon, const QDict *qdict);
+void hmp_replay_seek(Monitor *mon, const QDict *qdict);
#endif
diff --git a/qapi/replay.json b/qapi/replay.json
index e3266ef3a9..5d24cdc680 100644
--- a/qapi/replay.json
+++ b/qapi/replay.json
@@ -99,3 +99,23 @@
#
##
{ 'command': 'replay-delete-break' }
+
+##
+# @replay-seek:
+#
+# Automatically proceed to the instruction count @icount, when
+# replaying the execution. The command automatically loads nearest
+# snapshot and replays the execution to find the desired instruction.
+# When there is no preceding snapshot or the execution is not replayed,
+# then the command fails.
+# icount for the reference may be obtained with @query-replay command.
+#
+# @icount: target instruction count
+#
+# Since: 5.0
+#
+# Example:
+#
+# -> { "execute": "replay-seek", "data": { "icount": 220414 } }
+##
+{ 'command': 'replay-seek', 'data': { 'icount': 'int' } }
diff --git a/replay/replay-debugging.c b/replay/replay-debugging.c
index 166ba10d2c..f5a02a5aa1 100644
--- a/replay/replay-debugging.c
+++ b/replay/replay-debugging.c
@@ -19,6 +19,8 @@
#include "qapi/qapi-commands-replay.h"
#include "qapi/qmp/qdict.h"
#include "qemu/timer.h"
+#include "block/snapshot.h"
+#include "migration/snapshot.h"
void hmp_info_replay(Monitor *mon, const QDict *qdict)
{
@@ -127,3 +129,93 @@ void hmp_replay_delete_break(Monitor *mon, const QDict
*qdict)
return;
}
}
+
+static char *replay_find_nearest_snapshot(int64_t icount,
+ int64_t *snapshot_icount)
+{
+ BlockDriverState *bs;
+ QEMUSnapshotInfo *sn_tab;
+ QEMUSnapshotInfo *nearest = NULL;
+ char *ret = NULL;
+ int nb_sns, i;
+ AioContext *aio_context;
+
+ *snapshot_icount = -1;
+
+ bs = bdrv_all_find_vmstate_bs();
+ if (!bs) {
+ goto fail;
+ }
+ aio_context = bdrv_get_aio_context(bs);
+
+ aio_context_acquire(aio_context);
+ nb_sns = bdrv_snapshot_list(bs, &sn_tab);
+ aio_context_release(aio_context);
+
+ for (i = 0; i < nb_sns; i++) {
+ if (bdrv_all_find_snapshot(sn_tab[i].name, &bs) == 0) {
+ if (sn_tab[i].icount != -1ULL
+ && sn_tab[i].icount <= icount
+ && (!nearest || nearest->icount < sn_tab[i].icount)) {
+ nearest = &sn_tab[i];
+ }
+ }
+ }
+ if (nearest) {
+ ret = g_strdup(nearest->name);
+ *snapshot_icount = nearest->icount;
+ }
+ g_free(sn_tab);
+
+fail:
+ return ret;
+}
+
+static void replay_seek(int64_t icount, QEMUTimerCB callback, Error **errp)
+{
+ char *snapshot = NULL;
+ int64_t snapshot_icount;
+
+ if (replay_mode != REPLAY_MODE_PLAY) {
+ error_setg(errp, "replay must be enabled to seek");
+ return;
+ }
+ if (!replay_snapshot) {
+ error_setg(errp, "snapshotting is disabled");
+ return;
+ }
+
+ snapshot = replay_find_nearest_snapshot(icount, &snapshot_icount);
+ if (snapshot) {
+ if (icount < replay_get_current_icount()
+ || replay_get_current_icount() < snapshot_icount) {
+ vm_stop(RUN_STATE_RESTORE_VM);
+ load_snapshot(snapshot, errp);
+ }
+ g_free(snapshot);
+ }
+ if (replay_get_current_icount() <= icount) {
+ replay_break(icount, callback, NULL);
+ vm_start();
+ } else {
+ error_setg(errp, "cannot seek to the specified instruction count");
+ }
+}
+
+void qmp_replay_seek(int64_t icount, Error **errp)
+{
+ replay_seek(icount, replay_stop_vm, errp);
+}
+
+void hmp_replay_seek(Monitor *mon, const QDict *qdict)
+{
+ int64_t icount = qdict_get_try_int(qdict, "icount", -1LL);
+ Error *err = NULL;
+
+ qmp_replay_seek(icount, &err);
+ if (err) {
+ error_report_err(err);
+ error_free(err);
+ return;
+ }
+}
