On 15/08/2015 12:03, Paolo Bonzini wrote: > > > On 15/08/2015 11:57, Pavel Dovgalyuk wrote: >> Hi, Paolo! >> >> Will you apply these patches to 2.5? > > Yes, I'll put them in my next pull request.
Hi Pavel, unfortunately I do have some more review comments; that can happen when going back to the code after a few months, and it's also a good thing because it means that the code _is_ actually getting cleaner. However, I am fairly sure that v17 is going to be the good one and will be in 2.5 if I get it by mid September when I'll be back from vacation. In particular: * patch 3 seems to be unnecessary (for now at least) * replay_next_event_is is modified in patch 8 ("cpu: replay instructions sequence") after it's introduced in patch 6 ("replay: introduce icount event"). Please fold the change in patch 6. * replay_add_event is not used; please remove it, rename replay_add_event_internal to replay_add_event, and add an assertion that the rr mode is the right one (e.g. RECORD only?) * a couple of comments say "grteater" instead of "greater" * the replay_save_clock and replay_read_clock stubs should abort * please inline replay_input_event into qemu_input_event_send and replay_input_sync_event into qemu_input_event_sync, so that the corresponding *_impl functions can be static; this also means moving the prototypes of replay_add_input_event and replay_add_input_sync_event to replay/replay.h (I acknowledge this might undo a request from a previous review of mine; I don't remember) * most stubs are unnecessary (replay_get_current_step, replay_checkpoint, qemu_system_shutdown_request, qemu_input_event_send_impl, qemu_input_event_sync_impl) * please squash this in "replay: checkpoints" diff --git a/vl.c b/vl.c index 5a509dc..3c69563 100644 --- a/vl.c +++ b/vl.c @@ -1662,8 +1662,11 @@ static void qemu_kill_report(void) static int qemu_reset_requested(void) { int r = reset_requested; - reset_requested = 0; - return r; + if (r && replay_checkpoint(CHECKPOINT_RESET_REQUESTED)) { + reset_requested = 0; + return r; + } + return false; } static int qemu_suspend_requested(void) @@ -1862,9 +1865,7 @@ static bool main_loop_should_exit(void) return true; } } - if (qemu_reset_requested_get() - && replay_checkpoint(CHECKPOINT_RESET_REQUESTED)) { - qemu_reset_requested(); + if (qemu_reset_requested()) { pause_all_vcpus(); cpu_synchronize_all_states(); qemu_system_reset(VMRESET_REPORT); And a few questions. The first three are the "if the answer is yes, please do this" kind to questions, the others can have more open/subjective answers: * does it make sense to call replay_check_error from replay_finish_event, and remove the call from replay_read_next_clock? * should qemu_clock_use_for_deadline always return false in replay mode? The clocks are all deterministic, so it doesn't make sense to take them into account in the poll() deadline. * now that qemu_clock_warp has to be called in main_loop_wait, should the icount_warp_timer have a dummy callback? icount_warp_rt is then only called from qemu_clock_warp. If so, this (adding the call to qemu_clock_warp in main_loop_wait, making the icount_warp_timer dummy, removing the now-unnecessary argument of icount_warp_rt) should be a separate patch before "replay: checkpoints" * can you explain why both CHECKPOINT_INIT and CHECKPOINT_RESET are needed? What events are typically found in each of them? * would it make sense to test "replay_mode != REPLAY_MODE_NONE && !runstate_is_running()" in replay_checkpoint, for all checkpoints, like if (replay_mode != REPLAY_MODE_NONE && !runstate_is_running()) { return false; } ? * do we need an event for suspend? Thanks, Paolo