qemu-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Qemu-devel] [PATCH 4/9] runstate_set(): Check for valid transitions


From: Luiz Capitulino
Subject: [Qemu-devel] [PATCH 4/9] runstate_set(): Check for valid transitions
Date: Thu, 15 Sep 2011 17:05:44 -0300

This commit could have been folded with the previous one, however
doing it separately will allow for easy bisect and revert if needed.

Checking and testing all valid transitions wasn't trivial, chances
are this will need broader testing to become more stable.

This is a transition table as suggested by LluĂ­s Vilanova.

Signed-off-by: Luiz Capitulino <address@hidden>
---
 sysemu.h |    1 +
 vl.c     |   74 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 74 insertions(+), 1 deletions(-)

diff --git a/sysemu.h b/sysemu.h
index 19088aa..a01ddac 100644
--- a/sysemu.h
+++ b/sysemu.h
@@ -36,6 +36,7 @@ extern uint8_t qemu_uuid[];
 int qemu_uuid_parse(const char *str, uint8_t *uuid);
 #define UUID_FMT 
"%02hhx%02hhx%02hhx%02hhx-%02hhx%02hhx-%02hhx%02hhx-%02hhx%02hhx-%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx"
 
+void runstate_init(void);
 bool runstate_check(RunState state);
 void runstate_set(RunState new_state);
 typedef struct vm_change_state_entry VMChangeStateEntry;
diff --git a/vl.c b/vl.c
index 059e727..cc68fb3 100644
--- a/vl.c
+++ b/vl.c
@@ -327,14 +327,84 @@ static int default_driver_check(QemuOpts *opts, void 
*opaque)
 
 static RunState current_run_state = RSTATE_NO_STATE;
 
+typedef struct {
+    RunState from;
+    RunState to;
+} RunStateTransition;
+
+static const RunStateTransition runstate_transitions_def[] = {
+    /*     from      ->     to      */
+    { RSTATE_NO_STATE, RSTATE_RUNNING },
+    { RSTATE_NO_STATE, RSTATE_IN_MIGRATE },
+    { RSTATE_NO_STATE, RSTATE_PRE_LAUNCH },
+
+    { RSTATE_DEBUG, RSTATE_RUNNING },
+
+    { RSTATE_IN_MIGRATE, RSTATE_RUNNING },
+    { RSTATE_IN_MIGRATE, RSTATE_PRE_LAUNCH },
+
+    { RSTATE_PANICKED, RSTATE_PAUSED },
+
+    { RSTATE_IO_ERROR, RSTATE_RUNNING },
+
+    { RSTATE_PAUSED, RSTATE_RUNNING },
+
+    { RSTATE_POST_MIGRATE, RSTATE_RUNNING },
+
+    { RSTATE_PRE_LAUNCH, RSTATE_RUNNING },
+    { RSTATE_PRE_LAUNCH, RSTATE_POST_MIGRATE },
+
+    { RSTATE_PRE_MIGRATE, RSTATE_RUNNING },
+    { RSTATE_PRE_MIGRATE, RSTATE_POST_MIGRATE },
+
+    { RSTATE_RESTORE, RSTATE_RUNNING },
+
+    { RSTATE_RUNNING, RSTATE_DEBUG },
+    { RSTATE_RUNNING, RSTATE_PANICKED },
+    { RSTATE_RUNNING, RSTATE_IO_ERROR },
+    { RSTATE_RUNNING, RSTATE_PAUSED },
+    { RSTATE_RUNNING, RSTATE_PRE_MIGRATE },
+    { RSTATE_RUNNING, RSTATE_RESTORE },
+    { RSTATE_RUNNING, RSTATE_SAVEVM },
+    { RSTATE_RUNNING, RSTATE_SHUTDOWN },
+    { RSTATE_RUNNING, RSTATE_WATCHDOG },
+
+    { RSTATE_SAVEVM, RSTATE_RUNNING },
+
+    { RSTATE_SHUTDOWN, RSTATE_PAUSED },
+
+    { RSTATE_WATCHDOG, RSTATE_RUNNING },
+
+    { RSTATE_MAX, RSTATE_MAX },
+};
+
+static bool runstate_valid_transitions[RSTATE_MAX][RSTATE_MAX];
+
 bool runstate_check(RunState state)
 {
     return current_run_state == state;
 }
 
+void runstate_init(void)
+{
+    const RunStateTransition *p;
+
+    memset(&runstate_valid_transitions, 0, sizeof(runstate_valid_transitions));
+
+    for (p = &runstate_transitions_def[0]; p->from != RSTATE_MAX; p++) {
+        runstate_valid_transitions[p->from][p->to] = true;
+    }
+}
+
+/* This function will abort() on invalid state transitions */
 void runstate_set(RunState new_state)
 {
-    assert(new_state < RSTATE_MAX);
+    if (new_state >= RSTATE_MAX ||
+        !runstate_valid_transitions[current_run_state][new_state]) {
+        fprintf(stderr, "invalid runstate transition\n");
+        abort();
+    }
+
     current_run_state = new_state;
 }
 
@@ -2219,6 +2289,8 @@ int main(int argc, char **argv, char **envp)
     g_mem_set_vtable(&mem_trace);
     g_thread_init(NULL);
 
+    runstate_init();
+
     init_clocks();
 
     qemu_cache_utils_init(envp);
-- 
1.7.7.rc0.72.g4b5ea




reply via email to

[Prev in Thread] Current Thread [Next in Thread]