| Message ID | 20141107103304.6136.29222.stgit@PASHA-ISP |
|---|---|
| State | New |
| Headers | show |
On 07/11/2014 11:33, Pavel Dovgalyuk wrote: > This patch adds saving and replaying warping parameters in record and replay > modes. These parameters affect on virtual clock values and therefore should > be deterministic. Why are QEMU_CLOCK_REALTIME timers not recorded/replayed like QEMU_CLOCK_HOST is? Paolo > Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru> > --- > cpus.c | 24 +++++++++++++++++------- > 1 files changed, 17 insertions(+), 7 deletions(-) > > diff --git a/cpus.c b/cpus.c > index b41baf6..dac222b 100644 > --- a/cpus.c > +++ b/cpus.c > @@ -370,7 +370,9 @@ static void icount_warp_rt(void *opaque) > > seqlock_write_lock(&timers_state.vm_clock_seqlock); > if (runstate_is_running()) { > - int64_t clock = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); > + int64_t clock = qemu_clock_get_ns(replay_mode == REPLAY_MODE_NONE > + ? QEMU_CLOCK_REALTIME > + : QEMU_CLOCK_HOST); > int64_t warp_delta; > > warp_delta = clock - vm_clock_warp_start; > @@ -444,7 +446,9 @@ void qemu_clock_warp(QEMUClockType type) > } > > /* We want to use the earliest deadline from ALL vm_clocks */ > - clock = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); > + clock = qemu_clock_get_ns(replay_mode == REPLAY_MODE_NONE > + ? QEMU_CLOCK_REALTIME > + : QEMU_CLOCK_HOST); > deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL); > if (deadline < 0) { > return; > @@ -537,8 +541,10 @@ void configure_icount(QemuOpts *opts, Error **errp) > return; > } > icount_align_option = qemu_opt_get_bool(opts, "align", false); > - icount_warp_timer = timer_new_ns(QEMU_CLOCK_REALTIME, > - icount_warp_rt, NULL); > + icount_warp_timer = timer_new_ns(replay_mode == REPLAY_MODE_NONE > + ? QEMU_CLOCK_REALTIME > + : QEMU_CLOCK_HOST, > + icount_warp_rt, NULL); > if (strcmp(option, "auto") != 0) { > errno = 0; > icount_time_shift = strtol(option, &rem_str, 0); > @@ -562,10 +568,14 @@ void configure_icount(QemuOpts *opts, Error **errp) > the virtual time trigger catches emulated time passing too fast. > Realtime triggers occur even when idle, so use them less frequently > than VM triggers. */ > - icount_rt_timer = timer_new_ms(QEMU_CLOCK_REALTIME, > - icount_adjust_rt, NULL); > + icount_rt_timer = timer_new_ms(replay_mode == REPLAY_MODE_NONE > + ? QEMU_CLOCK_REALTIME > + : QEMU_CLOCK_HOST, > + icount_adjust_rt, NULL); > timer_mod(icount_rt_timer, > - qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + 1000); > + qemu_clock_get_ms(replay_mode == REPLAY_MODE_NONE > + ? QEMU_CLOCK_REALTIME > + : QEMU_CLOCK_HOST) + 1000); > icount_vm_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, > icount_adjust_vm, NULL); > timer_mod(icount_vm_timer, >
> From: Paolo Bonzini [mailto:pbonzini@redhat.com] > On 07/11/2014 11:33, Pavel Dovgalyuk wrote: > > This patch adds saving and replaying warping parameters in record and replay > > modes. These parameters affect on virtual clock values and therefore should > > be deterministic. > > Why are QEMU_CLOCK_REALTIME timers not recorded/replayed like > QEMU_CLOCK_HOST is? We cannot record all QEMU_CLOCK_REALTIME timers, because they are simulator-related timers, not the VM-related ones. If we'll record them then we'll have to replay simulator execution. And we want just to replay VM allowing different realtime events to be non-replayable (like screen refresh, monitor events handling, and so on). Pavel Dovgalyuk > > > Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru> > > --- > > cpus.c | 24 +++++++++++++++++------- > > 1 files changed, 17 insertions(+), 7 deletions(-) > > > > diff --git a/cpus.c b/cpus.c > > index b41baf6..dac222b 100644 > > --- a/cpus.c > > +++ b/cpus.c > > @@ -370,7 +370,9 @@ static void icount_warp_rt(void *opaque) > > > > seqlock_write_lock(&timers_state.vm_clock_seqlock); > > if (runstate_is_running()) { > > - int64_t clock = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); > > + int64_t clock = qemu_clock_get_ns(replay_mode == REPLAY_MODE_NONE > > + ? QEMU_CLOCK_REALTIME > > + : QEMU_CLOCK_HOST); > > int64_t warp_delta; > > > > warp_delta = clock - vm_clock_warp_start; > > @@ -444,7 +446,9 @@ void qemu_clock_warp(QEMUClockType type) > > } > > > > /* We want to use the earliest deadline from ALL vm_clocks */ > > - clock = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); > > + clock = qemu_clock_get_ns(replay_mode == REPLAY_MODE_NONE > > + ? QEMU_CLOCK_REALTIME > > + : QEMU_CLOCK_HOST); > > deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL); > > if (deadline < 0) { > > return; > > @@ -537,8 +541,10 @@ void configure_icount(QemuOpts *opts, Error **errp) > > return; > > } > > icount_align_option = qemu_opt_get_bool(opts, "align", false); > > - icount_warp_timer = timer_new_ns(QEMU_CLOCK_REALTIME, > > - icount_warp_rt, NULL); > > + icount_warp_timer = timer_new_ns(replay_mode == REPLAY_MODE_NONE > > + ? QEMU_CLOCK_REALTIME > > + : QEMU_CLOCK_HOST, > > + icount_warp_rt, NULL); > > if (strcmp(option, "auto") != 0) { > > errno = 0; > > icount_time_shift = strtol(option, &rem_str, 0); > > @@ -562,10 +568,14 @@ void configure_icount(QemuOpts *opts, Error **errp) > > the virtual time trigger catches emulated time passing too fast. > > Realtime triggers occur even when idle, so use them less frequently > > than VM triggers. */ > > - icount_rt_timer = timer_new_ms(QEMU_CLOCK_REALTIME, > > - icount_adjust_rt, NULL); > > + icount_rt_timer = timer_new_ms(replay_mode == REPLAY_MODE_NONE > > + ? QEMU_CLOCK_REALTIME > > + : QEMU_CLOCK_HOST, > > + icount_adjust_rt, NULL); > > timer_mod(icount_rt_timer, > > - qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + 1000); > > + qemu_clock_get_ms(replay_mode == REPLAY_MODE_NONE > > + ? QEMU_CLOCK_REALTIME > > + : QEMU_CLOCK_HOST) + 1000); > > icount_vm_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, > > icount_adjust_vm, NULL); > > timer_mod(icount_vm_timer, > >
On 07/11/2014 12:45, Pavel Dovgaluk wrote: >> From: Paolo Bonzini [mailto:pbonzini@redhat.com] >> On 07/11/2014 11:33, Pavel Dovgalyuk wrote: >>> This patch adds saving and replaying warping parameters in record and replay >>> modes. These parameters affect on virtual clock values and therefore should >>> be deterministic. >> >> Why are QEMU_CLOCK_REALTIME timers not recorded/replayed like >> QEMU_CLOCK_HOST is? > > We cannot record all QEMU_CLOCK_REALTIME timers, because they are simulator-related timers, > not the VM-related ones. If we'll record them then we'll have to replay simulator > execution. And we want just to replay VM allowing different realtime events to be > non-replayable (like screen refresh, monitor events handling, and so on). Hmm... I think you want the icount_rt timer to use what QEMU_CLOCK_VIRTUAL does in !use_icount mode. Maybe you can add a fourth clock, QEMU_CLOCK_VIRTUAL_RT and use this one independent of the replay mode. This clock can then be traced like QEMU_CLOCK_HOST. The problem is that QEMU_CLOCK_HOST can move backwards or forwards, sometimes by as much as 1 hour, so it's not the best match for this case. Paolo
diff --git a/cpus.c b/cpus.c index b41baf6..dac222b 100644 --- a/cpus.c +++ b/cpus.c @@ -370,7 +370,9 @@ static void icount_warp_rt(void *opaque) seqlock_write_lock(&timers_state.vm_clock_seqlock); if (runstate_is_running()) { - int64_t clock = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); + int64_t clock = qemu_clock_get_ns(replay_mode == REPLAY_MODE_NONE + ? QEMU_CLOCK_REALTIME + : QEMU_CLOCK_HOST); int64_t warp_delta; warp_delta = clock - vm_clock_warp_start; @@ -444,7 +446,9 @@ void qemu_clock_warp(QEMUClockType type) } /* We want to use the earliest deadline from ALL vm_clocks */ - clock = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); + clock = qemu_clock_get_ns(replay_mode == REPLAY_MODE_NONE + ? QEMU_CLOCK_REALTIME + : QEMU_CLOCK_HOST); deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL); if (deadline < 0) { return; @@ -537,8 +541,10 @@ void configure_icount(QemuOpts *opts, Error **errp) return; } icount_align_option = qemu_opt_get_bool(opts, "align", false); - icount_warp_timer = timer_new_ns(QEMU_CLOCK_REALTIME, - icount_warp_rt, NULL); + icount_warp_timer = timer_new_ns(replay_mode == REPLAY_MODE_NONE + ? QEMU_CLOCK_REALTIME + : QEMU_CLOCK_HOST, + icount_warp_rt, NULL); if (strcmp(option, "auto") != 0) { errno = 0; icount_time_shift = strtol(option, &rem_str, 0); @@ -562,10 +568,14 @@ void configure_icount(QemuOpts *opts, Error **errp) the virtual time trigger catches emulated time passing too fast. Realtime triggers occur even when idle, so use them less frequently than VM triggers. */ - icount_rt_timer = timer_new_ms(QEMU_CLOCK_REALTIME, - icount_adjust_rt, NULL); + icount_rt_timer = timer_new_ms(replay_mode == REPLAY_MODE_NONE + ? QEMU_CLOCK_REALTIME + : QEMU_CLOCK_HOST, + icount_adjust_rt, NULL); timer_mod(icount_rt_timer, - qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + 1000); + qemu_clock_get_ms(replay_mode == REPLAY_MODE_NONE + ? QEMU_CLOCK_REALTIME + : QEMU_CLOCK_HOST) + 1000); icount_vm_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, icount_adjust_vm, NULL); timer_mod(icount_vm_timer,
This patch adds saving and replaying warping parameters in record and replay modes. These parameters affect on virtual clock values and therefore should be deterministic. Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru> --- cpus.c | 24 +++++++++++++++++------- 1 files changed, 17 insertions(+), 7 deletions(-)