diff options
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/devel/index-tcg.rst | 1 | ||||
| -rw-r--r-- | docs/devel/replay.rst (renamed from docs/devel/replay.txt) | 16 |
2 files changed, 13 insertions, 4 deletions
diff --git a/docs/devel/index-tcg.rst b/docs/devel/index-tcg.rst index 0b0ad12..7b9760b 100644 --- a/docs/devel/index-tcg.rst +++ b/docs/devel/index-tcg.rst @@ -13,3 +13,4 @@ are only implementing things for HW accelerated hypervisors. multi-thread-tcg tcg-icount tcg-plugins + replay diff --git a/docs/devel/replay.txt b/docs/devel/replay.rst index e641c35..dd8bf3b 100644 --- a/docs/devel/replay.txt +++ b/docs/devel/replay.rst @@ -1,3 +1,11 @@ +.. + Copyright (c) 2022, ISP RAS + Written by Pavel Dovgalyuk + +======================= +Execution Record/Replay +======================= + Record/replay mechanism, that could be enabled through icount mode, expects the virtual devices to satisfy the following requirements. @@ -5,7 +13,7 @@ The main idea behind this document is that everything that affects the guest state during execution in icount mode should be deterministic. Timers -====== +------ All virtual devices should use virtual clock for timers that change the guest state. Virtual clock is deterministic, therefore such timers are deterministic @@ -19,7 +27,7 @@ the virtual devices (e.g., slirp routing device) that lie outside the replayed guest. Bottom halves -============= +------------- Bottom half callbacks, that affect the guest state, should be invoked through replay_bh_schedule_event or replay_bh_schedule_oneshot_event functions. @@ -27,7 +35,7 @@ Their invocations are saved in record mode and synchronized with the existing log in replay mode. Saving/restoring the VM state -============================= +----------------------------- All fields in the device state structure (including virtual timers) should be restored by loadvm to the same values they had before savevm. @@ -38,7 +46,7 @@ is not defined. It means that you should not call functions like the dependencies that may make restoring the VM state non-deterministic. Stopping the VM -=============== +--------------- Stopping the guest should not interfere with its state (with the exception of the network connections, that could be broken by the remote timeouts). |