diff mbox

[RFC,v3,47/49] replay: replay_break command

Message ID 20140731125754.1600.94323.stgit@PASHA-ISP.novsu.ac.ru
State New
Headers show

Commit Message

Pavel Dovgalyuk July 31, 2014, 12:57 p.m. UTC
This patch adds support for replay_break monitor command. This command
sets the step (measured in executed instructions) where replay should be
stopped.

Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru>
---
 hmp-commands.hx     |   14 ++++++++++++++
 monitor.c           |   20 ++++++++++++++++++++
 qapi-schema.json    |   19 ++++++++++++++++++-
 qmp-commands.hx     |   34 +++++++++++++++++++++++++++++++---
 replay/replay-qmp.c |   14 ++++++++++++++
 replay/replay.c     |   29 ++++++++++++++++++++++++++++-
 replay/replay.h     |    4 ++++
 7 files changed, 129 insertions(+), 5 deletions(-)
diff mbox

Patch

diff --git a/hmp-commands.hx b/hmp-commands.hx
index 19174f1..3eaa80e 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -1801,6 +1801,20 @@  STEXI
 Shows information about replay process.
 ETEXI
 
+    {
+        .name       = "replay_break",
+        .args_type  = "step:l",
+        .params     = "step",
+        .help       = "stop replaying at the specified replay step",
+        .mhandler.cmd = do_replay_break,
+    },
+
+STEXI
+@item replay_break @var{step}
+Stops replaying at the specified @var{step}.
+
+ETEXI
+
 STEXI
 @end table
 ETEXI
diff --git a/monitor.c b/monitor.c
index 61fb11c..1ba9096 100644
--- a/monitor.c
+++ b/monitor.c
@@ -1184,8 +1184,12 @@  static void do_replay_info(Monitor *mon, const QDict *qdict)
         monitor_printf(mon, "Replay mode: %s ",
                        ReplayMode_lookup[replay_mode]);
         if (replay_mode == REPLAY_MODE_PLAY) {
+            uint64_t bp = replay_get_break_step();
             monitor_printf(mon, "(%s)",
                            ReplaySubmode_lookup[replay_get_play_submode()]);
+            if (bp != -1ULL) {
+                monitor_printf(mon, "\n\tbreakpoint step: %" PRId64 "\n", bp);
+            }
         }
         monitor_printf(mon, "\n\tcurrent step: %" PRId64 "\n",
                        replay_get_current_step());
@@ -1193,6 +1197,22 @@  static void do_replay_info(Monitor *mon, const QDict *qdict)
     }
 }
 
+static void do_replay_break(Monitor *mon, const QDict *qdict)
+{
+    if (replay_mode == REPLAY_MODE_PLAY) {
+        uint64_t step = qdict_get_int(qdict, "step");
+        if (step >= replay_get_current_step()) {
+            monitor_printf(mon, "Setting break at step: %" PRId64 "\n", step);
+            replay_set_break(step);
+        } else {
+            monitor_printf(mon, "Cannot stop on the preceding step.\n");
+        }
+    } else {
+        monitor_printf(mon, "You can stop at the specific step "
+                            "only in PLAY mode.\n");
+    }
+}
+
 static void monitor_printc(Monitor *mon, int c)
 {
     monitor_printf(mon, "'");
diff --git a/qapi-schema.json b/qapi-schema.json
index 93a7ff7..e56e399 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -3535,10 +3535,13 @@ 
 #
 # @step: current step of record or play
 #
+# @break-step: step where execution should stop
+#
 # Since: 2.2
 ##
 { 'type': 'ReplayInfo',
-  'data': {'mode': 'ReplayMode', 'submode': 'ReplaySubmode', 'step': 'uint64'} }
+  'data': { 'mode': 'ReplayMode', 'submode': 'ReplaySubmode',
+            'step': 'uint64', 'break-step': 'uint64' } }
 
 ##
 # @replay-info
@@ -3550,3 +3553,17 @@ 
 # Since: 2.2
 ##
 { 'command': 'replay-info', 'returns': 'ReplayInfo' }
+
+##
+# @replay-break
+#
+# Sets breakpoint at the specified step of replaying.
+# This command can be used in replay to stop execution when
+# the specified step is reached.
+# Current step of the execution can be queried with replay-info command.
+#
+# @step: step where breakpoint should be set
+#
+# Since: 2.2
+##
+{ 'command': 'replay-break', 'data': { 'step': 'uint64' } }
diff --git a/qmp-commands.hx b/qmp-commands.hx
index 67dd886..712cb5b 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -3768,12 +3768,40 @@  replay-info
 
 Shows information about replay process. This information includes
 current execution step (number of executed processor instructions),
-replay mode (record, play or none), and replay submode (reverse or
-normal execution in play mode).
+replay mode (record, play or none), replay submode (reverse or
+normal execution in play mode), and breakpoint step.
 
 Example:
 
 -> { "execute": "replay-info" }
-<- { "return": { "step": 651488674, "mode": "record", "submode": "unknown" } }
+<- { "return": { "step": 651488674,
+                 "mode": "record", "submode": "unknown"
+                 "break-step": 651490000 } }
+
+EQMP
+
+    {
+        .name       = "replay-break",
+        .args_type  = "step:l",
+        .mhandler.cmd_new = qmp_marshal_input_replay_break,
+    },
+
+SQMP
+replay-break
+------------
+
+Sets breakpoint at the specified step of replaying.
+This command can be used in replay to stop execution when
+the specified step is reached.
+Current step of the execution can be queried with replay-info command.
+
+Arguments:
+
+- "step": step where breakpoint should be set
+
+Example:
+
+-> { "execute": "replay-break", "arguments": { "step": 1024 } }
+<- { "return": {} }
 
 EQMP
diff --git a/replay/replay-qmp.c b/replay/replay-qmp.c
index 4a0017d..f48b816 100755
--- a/replay/replay-qmp.c
+++ b/replay/replay-qmp.c
@@ -24,6 +24,20 @@  ReplayInfo *qmp_replay_info(Error **errp)
     info->mode = replay_mode;
     info->submode = replay_get_play_submode();
     info->step = replay_get_current_step();
+    info->break_step = replay_get_break_step();
 
     return info;
 }
+
+void qmp_replay_break(uint64_t step, Error **errp)
+{
+    if (replay_mode == REPLAY_MODE_PLAY) {
+        if (step >= replay_get_current_step()) {
+            replay_set_break(step);
+        } else {
+            error_setg(errp, "Cannot stop on the preceding step");
+        }
+    } else {
+        error_setg(errp, "replay_break can be used only in PLAY mode");
+    }
+}
diff --git a/replay/replay.c b/replay/replay.c
index 4151330..fac5ecd 100755
--- a/replay/replay.c
+++ b/replay/replay.c
@@ -31,6 +31,8 @@  static char *replay_filename;
 char *replay_image_suffix;
 
 ReplayState replay_state;
+/*! Step for stopping execution at. */
+static uint64_t replay_break_step = -1;
 
 /*
     Auto-saving for VM states data
@@ -285,6 +287,19 @@  void replay_instruction(int process_events)
         } else if (replay_mode == REPLAY_MODE_PLAY) {
             skip_async_events_until(EVENT_INSTRUCTION);
             if (first_cpu->instructions_count >= 1) {
+                if (replay_get_current_step() == replay_break_step) {
+                    replay_break_step = -1;
+
+                    /* for stopping VM */
+                    if (play_submode == REPLAY_SUBMODE_NORMAL) {
+                        first_cpu->exception_index = EXCP_DEBUG;
+                        monitor_printf(default_mon, "Execution has stopped.\n");
+                        vm_stop(EXCP_DEBUG);
+                    }
+                    /* for breaking execution loop */
+                    cpu_exit(first_cpu);
+                    return;
+                }
                 ++replay_state.current_step;
                 --first_cpu->instructions_count;
                 if (first_cpu->instructions_count == 0) {
@@ -313,7 +328,8 @@  bool replay_has_async_request(void)
     }
 
     if (replay_mode == REPLAY_MODE_PLAY) {
-        if (skip_async_events(EVENT_ASYNC)) {
+        if (skip_async_events(EVENT_ASYNC)
+            || replay_get_current_step() == replay_break_step) {
             return true;
         }
 
@@ -471,6 +487,7 @@  static void replay_enable(const char *fname, int mode)
     replay_state.skipping_instruction = 0;
     replay_state.current_step = 0;
     current_saved_state = 0;
+    replay_break_step = -1;
 
     replay_net_init();
 
@@ -643,3 +660,13 @@  void replay_data_buffer(unsigned char *data, size_t size)
         replay_put_array(data, size);
     }
 }
+
+void replay_set_break(uint64_t step)
+{
+    replay_break_step = step;
+}
+
+uint64_t replay_get_break_step(void)
+{
+    return replay_break_step;
+}
diff --git a/replay/replay.h b/replay/replay.h
index 590f9e6..e737eba 100755
--- a/replay/replay.h
+++ b/replay/replay.h
@@ -53,6 +53,10 @@  void replay_configure(struct QemuOpts *opts, int mode);
 void replay_init_timer(void);
 /*! Closes replay log file and frees other resources. */
 void replay_finish(void);
+/*! Sets step where execution should be stopped. */
+void replay_set_break(uint64_t step);
+/*! Retrieves current breakpoint step. */
+uint64_t replay_get_break_step(void);
 
 /* Processing the instructions */