diff options
| -rw-r--r-- | docs/replay.txt | 16 | ||||
| -rw-r--r-- | include/sysemu/replay.h | 9 | ||||
| -rw-r--r-- | qemu-options.hx | 8 | ||||
| -rw-r--r-- | replay/replay-snapshot.c | 17 | ||||
| -rw-r--r-- | replay/replay.c | 5 | ||||
| -rw-r--r-- | vl.c | 7 |
6 files changed, 59 insertions, 3 deletions
diff --git a/docs/replay.txt b/docs/replay.txt index 347b2ff055..03e193193f 100644 --- a/docs/replay.txt +++ b/docs/replay.txt @@ -196,6 +196,22 @@ is recorded to the log. In replay phase the queue is matched with events read from the log. Therefore block devices requests are processed deterministically. +Snapshotting +------------ + +New VM snapshots may be created in replay mode. They can be used later +to recover the desired VM state. All VM states created in replay mode +are associated with the moment of time in the replay scenario. +After recovering the VM state replay will start from that position. + +Default starting snapshot name may be specified with icount field +rrsnapshot as follows: + -icount shift=7,rr=record,rrfile=replay.bin,rrsnapshot=snapshot_name + +This snapshot is created at start of recording and restored at start +of replaying. It also can be loaded while replaying to roll back +the execution. + Network devices --------------- diff --git a/include/sysemu/replay.h b/include/sysemu/replay.h index abb35ca8c9..740b425fe4 100644 --- a/include/sysemu/replay.h +++ b/include/sysemu/replay.h @@ -43,6 +43,9 @@ typedef struct ReplayNetState ReplayNetState; extern ReplayMode replay_mode; +/* Name of the initial VM snapshot */ +extern char *replay_snapshot; + /* Replay process control functions */ /*! Enables recording or saving event log with specified parameters */ @@ -149,4 +152,10 @@ void replay_unregister_net(ReplayNetState *rns); void replay_net_packet_event(ReplayNetState *rns, unsigned flags, const struct iovec *iov, int iovcnt); +/* VM state operations */ + +/*! Called at the start of execution. + Loads or saves initial vmstate depending on execution mode. */ +void replay_vmstate_init(void); + #endif diff --git a/qemu-options.hx b/qemu-options.hx index 588e5beab3..b1baa0d8f9 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -3400,12 +3400,12 @@ re-inject them. ETEXI DEF("icount", HAS_ARG, QEMU_OPTION_icount, \ - "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>]\n" \ + "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>,rrsnapshot=<snapshot>]\n" \ " enable virtual instruction counter with 2^N clock ticks per\n" \ " instruction, enable aligning the host and virtual clocks\n" \ " or disable real time cpu sleeping\n", QEMU_ARCH_ALL) STEXI -@item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename}] +@item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename},rrsnapshot=@var{snapshot}] @findex -icount Enable virtual instruction counter. The virtual cpu will execute one instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified @@ -3438,6 +3438,10 @@ when the shift value is high (how high depends on the host machine). When @option{rr} option is specified deterministic record/replay is enabled. Replay log is written into @var{filename} file in record mode and read from this file in replay mode. + +Option rrsnapshot is used to create new vm snapshot named @var{snapshot} +at the start of execution recording. In replay mode this option is used +to load the initial VM state. ETEXI DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \ diff --git a/replay/replay-snapshot.c b/replay/replay-snapshot.c index 498059734d..65e2d375c2 100644 --- a/replay/replay-snapshot.c +++ b/replay/replay-snapshot.c @@ -59,3 +59,20 @@ void replay_vmstate_register(void) { vmstate_register(NULL, 0, &vmstate_replay, &replay_state); } + +void replay_vmstate_init(void) +{ + if (replay_snapshot) { + if (replay_mode == REPLAY_MODE_RECORD) { + if (save_vmstate(cur_mon, replay_snapshot) != 0) { + error_report("Could not create snapshot for icount record"); + exit(1); + } + } else if (replay_mode == REPLAY_MODE_PLAY) { + if (load_vmstate(replay_snapshot) != 0) { + error_report("Could not load snapshot for icount replay"); + exit(1); + } + } + } +} diff --git a/replay/replay.c b/replay/replay.c index 7f27cf17b0..1835b9902e 100644 --- a/replay/replay.c +++ b/replay/replay.c @@ -26,6 +26,7 @@ #define HEADER_SIZE (sizeof(uint32_t) + sizeof(uint64_t)) ReplayMode replay_mode = REPLAY_MODE_NONE; +char *replay_snapshot; /* Name of replay file */ static char *replay_filename; @@ -292,6 +293,7 @@ void replay_configure(QemuOpts *opts) exit(1); } + replay_snapshot = g_strdup(qemu_opt_get(opts, "rrsnapshot")); replay_vmstate_register(); replay_enable(fname, mode); @@ -346,6 +348,9 @@ void replay_finish(void) replay_filename = NULL; } + g_free(replay_snapshot); + replay_snapshot = NULL; + replay_finish_events(); replay_mutex_destroy(); } @@ -465,6 +465,9 @@ static QemuOptsList qemu_icount_opts = { }, { .name = "rrfile", .type = QEMU_OPT_STRING, + }, { + .name = "rrsnapshot", + .type = QEMU_OPT_STRING, }, { /* end of list */ } }, @@ -4634,7 +4637,9 @@ int main(int argc, char **argv, char **envp) replay_checkpoint(CHECKPOINT_RESET); qemu_system_reset(VMRESET_SILENT); register_global_state(); - if (loadvm) { + if (replay_mode != REPLAY_MODE_NONE) { + replay_vmstate_init(); + } else if (loadvm) { if (load_vmstate(loadvm) < 0) { autostart = 0; } |