aboutsummaryrefslogtreecommitdiff
path: root/docs/devel
diff options
context:
space:
mode:
authorPavel Dovgalyuk <pavel.dovgalyuk@ispras.ru>2022-05-27 13:46:30 +0300
committerPaolo Bonzini <pbonzini@redhat.com>2022-06-06 09:26:53 +0200
commit04d0583a4f5d00061bf57d17947aa0d5c6a6cecf (patch)
tree270e194c1f501b01d270e095b48b2dcd9bbaa65b /docs/devel
parent3e21408b0596aa2babe1e26996a15e7ad5eee71a (diff)
docs: convert docs/devel/replay page to rst
This patch converts prior .txt replay devel documentation to .rst. Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-Id: <165364839013.688121.11935249420738873044.stgit@pasha-ThinkPad-X280> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'docs/devel')
-rw-r--r--docs/devel/index-tcg.rst1
-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 0b0ad12c22..7b9760b26f 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 e641c35add..dd8bf3b195 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).