| Message ID | 154703595509.13472.7357387659078524086.stgit@pasha-VirtualBox |
|---|---|
| State | New |
| Headers | show |
| Series | Fixing record/replay and adding reverse debugging | expand |
Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru> writes: > This patch adds hmp/qmp commands replay_seek/replay-seek that proceed > the execution to the specified step. > The command automatically loads nearest snapshot and replay the execution > to find the desired step. "step" again. > > Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru> > > -- > > 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) > --- > hmp-commands.hx | 19 +++++++++ > hmp.h | 1 > qapi/replay.json | 20 ++++++++++ > replay/replay-debugging.c | 91 +++++++++++++++++++++++++++++++++++++++++++++ > 4 files changed, 131 insertions(+) > > diff --git a/hmp-commands.hx b/hmp-commands.hx > index 6d04c02..2839acc 100644 > --- a/hmp-commands.hx > +++ b/hmp-commands.hx > @@ -1924,6 +1924,25 @@ The command is ignored when there are no replay breakpoints. > ETEXI > > { > + .name = "replay_seek", > + .args_type = "icount:i", > + .params = "icount", > + .help = "rewinds replay to the step specified by icount", We use imperative mood in .help: "rewind". "Rewind" suggests going backward. The command can do that. But it can also go forward. What about: "replay execution to the specified intruction count" > + .cmd = hmp_replay_seek, > + }, > + > +STEXI > +@item replay_seek @var{icount} > +@findex replay_seek > +Automatically proceeds to the step specified by @var{icount}, when > +replaying the execution. The command automatically loads nearest > +snapshot and replay the execution to find the desired step. > +When there is no preceding snapshot or the execution is not replayed, > +then the command is ignored. Uh, why isn't that an error? > +icount for the reference may be observed with 'info replay' command. This still uses both "step" and "instruction count". I'm happy to help rephrasing, but first we need to nail down the failure modes. > +ETEXI > + > + { > .name = "info", > .args_type = "item:s?", > .params = "[subcommand]", > diff --git a/hmp.h b/hmp.h > index c9b9b4f..d6e1d7e 100644 > --- a/hmp.h > +++ b/hmp.h > @@ -151,5 +151,6 @@ 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 a63219c..7390f88 100644 > --- a/qapi/replay.json > +++ b/qapi/replay.json > @@ -99,3 +99,23 @@ > # > ## > { 'command': 'replay-delete-break' } > + > +## > +# @replay-seek: > +# > +# Automatically proceeds to the step specified by @icount when replaying > +# the execution. The command automatically loads nearest > +# snapshot and replay the execution to find the desired step. > +# When there is no preceding snapshot or the execution is not replayed, > +# then the command is ignored. > +# icount for the reference may be obtained with @query-replay command. My comments on hmp-commands.hx apply. > +# > +# @icount: destination execution step s/execution step/instruction count/ Maybe s/destination/target/ > +# > +# Since: 4.0 > +# > +# Example: > +# > +# -> { "execute": "replay-seek", "data": { "icount": 220414 } } > +## > +{ 'command': 'replay-seek', 'data': { 'icount': 'int' } } [...]
> From: Markus Armbruster [mailto:armbru@redhat.com] > Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru> writes: > > > This patch adds hmp/qmp commands replay_seek/replay-seek that proceed > > the execution to the specified step. > > The command automatically loads nearest snapshot and replay the execution > > to find the desired step. > > "step" again. > > > > > Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru> > > > > -- > > > > 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) > > --- > > hmp-commands.hx | 19 +++++++++ > > hmp.h | 1 > > qapi/replay.json | 20 ++++++++++ > > replay/replay-debugging.c | 91 +++++++++++++++++++++++++++++++++++++++++++++ > > 4 files changed, 131 insertions(+) > > > > diff --git a/hmp-commands.hx b/hmp-commands.hx > > index 6d04c02..2839acc 100644 > > --- a/hmp-commands.hx > > +++ b/hmp-commands.hx > > @@ -1924,6 +1924,25 @@ The command is ignored when there are no replay breakpoints. > > ETEXI > > > > { > > + .name = "replay_seek", > > + .args_type = "icount:i", > > + .params = "icount", > > + .help = "rewinds replay to the step specified by icount", > > We use imperative mood in .help: "rewind". > > "Rewind" suggests going backward. The command can do that. But it can > also go forward. What about: > > "replay execution to the specified intruction count" > > > + .cmd = hmp_replay_seek, > > + }, > > + > > +STEXI > > +@item replay_seek @var{icount} > > +@findex replay_seek > > +Automatically proceeds to the step specified by @var{icount}, when > > +replaying the execution. The command automatically loads nearest > > +snapshot and replay the execution to find the desired step. > > +When there is no preceding snapshot or the execution is not replayed, > > +then the command is ignored. > > Uh, why isn't that an error? What about this one? Automatically proceeds 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 is ignored and error message is displayed. icount for the reference may be observed with 'info replay' command. Pavel Dovgalyuk
diff --git a/hmp-commands.hx b/hmp-commands.hx index 6d04c02..2839acc 100644 --- a/hmp-commands.hx +++ b/hmp-commands.hx @@ -1924,6 +1924,25 @@ The command is ignored when there are no replay breakpoints. ETEXI { + .name = "replay_seek", + .args_type = "icount:i", + .params = "icount", + .help = "rewinds replay to the step specified by icount", + .cmd = hmp_replay_seek, + }, + +STEXI +@item replay_seek @var{icount} +@findex replay_seek +Automatically proceeds to the step specified by @var{icount}, when +replaying the execution. The command automatically loads nearest +snapshot and replay the execution to find the desired step. +When there is no preceding snapshot or the execution is not replayed, +then the command is ignored. +icount for the reference may be observed with 'info replay' command. +ETEXI + + { .name = "info", .args_type = "item:s?", .params = "[subcommand]", diff --git a/hmp.h b/hmp.h index c9b9b4f..d6e1d7e 100644 --- a/hmp.h +++ b/hmp.h @@ -151,5 +151,6 @@ 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 a63219c..7390f88 100644 --- a/qapi/replay.json +++ b/qapi/replay.json @@ -99,3 +99,23 @@ # ## { 'command': 'replay-delete-break' } + +## +# @replay-seek: +# +# Automatically proceeds to the step specified by @icount when replaying +# the execution. The command automatically loads nearest +# snapshot and replay the execution to find the desired step. +# When there is no preceding snapshot or the execution is not replayed, +# then the command is ignored. +# icount for the reference may be obtained with @query-replay command. +# +# @icount: destination execution step +# +# Since: 4.0 +# +# 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 8ee64b2..39848dc 100644 --- a/replay/replay-debugging.c +++ b/replay/replay-debugging.c @@ -18,6 +18,8 @@ #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) { @@ -125,3 +127,92 @@ void hmp_replay_delete_break(Monitor *mon, const QDict *qdict) return; } } + +static char *replay_find_nearest_snapshot(int64_t step, int64_t* snapshot_step) +{ + BlockDriverState *bs; + QEMUSnapshotInfo *sn_tab; + QEMUSnapshotInfo *nearest = NULL; + char *ret = NULL; + int nb_sns, i; + AioContext *aio_context; + + *snapshot_step = -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 <= step + && (!nearest || nearest->icount < sn_tab[i].icount)) { + nearest = &sn_tab[i]; + } + } + } + if (nearest) { + ret = g_strdup(nearest->name); + *snapshot_step = nearest->icount; + } + g_free(sn_tab); + +fail: + return ret; +} + +static void replay_seek(int64_t step, QEMUTimerCB callback, Error **errp) +{ + char *snapshot = NULL; + int64_t snapshot_step; + + 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(step, &snapshot_step); + if (snapshot) { + if (step < replay_get_current_step() + || replay_get_current_step() < snapshot_step) { + vm_stop(RUN_STATE_RESTORE_VM); + load_snapshot(snapshot, errp); + } + g_free(snapshot); + } + if (replay_get_current_step() <= step) { + replay_break(step, callback, NULL); + vm_start(); + } else { + error_setg(errp, "cannot seek to the specified step"); + } +} + +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 step = qdict_get_try_int(qdict, "icount", -1LL); + Error *err = NULL; + + qmp_replay_seek(step, &err); + if (err) { + error_report_err(err); + error_free(err); + return; + } +}
This patch adds hmp/qmp commands replay_seek/replay-seek that proceed the execution to the specified step. The command automatically loads nearest snapshot and replay the execution to find the desired step. Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru> -- 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) --- hmp-commands.hx | 19 +++++++++ hmp.h | 1 qapi/replay.json | 20 ++++++++++ replay/replay-debugging.c | 91 +++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 131 insertions(+)