Add time validation to health check

[lttng-tools.git] / src / bin / lttng-sessiond / health.h

diff --git a/src/bin/lttng-sessiond/health.h b/src/bin/lttng-sessiond/health.h
index 9a1ef391a55b4bb00a7de30a5e867aacfbdaf2cf..b348be5f0144e85b4309624c747026c0090d5e3c 100644 (file)
--- a/src/bin/lttng-sessiond/health.h
+++ b/src/bin/lttng-sessiond/health.h
@@ -19,26 +19,44 @@
 #define _HEALTH_H
 
 #include <stdint.h>
+#include <time.h>
 #include <urcu/uatomic.h>
 
 /*
  * These are the value added to the current state depending of the position in
  * the thread where is either waiting on a poll() or running in the code.
  */
-#define HEALTH_POLL_VALUE 1
-#define HEALTH_CODE_VALUE 2
+#define HEALTH_POLL_VALUE      (1UL << 0)
+#define HEALTH_CODE_VALUE      (1UL << 1)
 
-#define HEALTH_IS_IN_POLL(x) (x % HEALTH_CODE_VALUE)
-#define HEALTH_IS_IN_CODE(x) (x % HEALTH_POLL_VALUE)
+#define HEALTH_IS_IN_POLL(x)   ((x) & HEALTH_POLL_VALUE)
+
+enum health_flags {
+       HEALTH_EXIT =  (1U << 0),
+       HEALTH_ERROR = (1U << 1),
+};
 
 struct health_state {
-       uint64_t last;
-       uint64_t current;
+       /*
+        * last counter and last_time are only read and updated by the health_check
+        * thread (single updater).
+        */
+       unsigned long last;
+       struct timespec last_time;
+
+       /*
+        * current and flags are updated by multiple threads concurrently.
+        */
+       unsigned long current;          /* progress counter, updated atomically */
+       enum health_flags flags;        /* other flags, updated atomically */
 };
 
 /* Health state counters for the client command thread */
 extern struct health_state health_thread_cmd;
 
+/* Health state counters for the application management thread */
+extern struct health_state health_thread_app_manage;
+
 /* Health state counters for the application registration thread */
 extern struct health_state health_thread_app_reg;
 
@@ -46,36 +64,41 @@ extern struct health_state health_thread_app_reg;
 extern struct health_state health_thread_kernel;
 
 /*
- * Update current counter by 1 to indicate that the thread is in a blocking
- * state cause by a poll().
+ * Update current counter by 1 to indicate that the thread entered or
+ * left a blocking state caused by a poll().
  */
 static inline void health_poll_update(struct health_state *state)
 {
        assert(state);
-
        uatomic_add(&state->current, HEALTH_POLL_VALUE);
 }
 
 /*
- * Update current counter by 2 which indicates that we are currently running in
- * a thread and NOT blocked at a poll().
+ * Update current counter by 2 indicates progress in execution of a
+ * thread.
  */
 static inline void health_code_update(struct health_state *state)
 {
        assert(state);
-
        uatomic_add(&state->current, HEALTH_CODE_VALUE);
 }
 
 /*
- * Reset health state. A value of zero indicate a bad health state.
+ * Set health "exit" flag.
  */
-static inline void health_reset(struct health_state *state)
+static inline void health_exit(struct health_state *state)
 {
        assert(state);
+       uatomic_or(&state->flags, HEALTH_EXIT);
+}
 
-       uatomic_set(&state->current, 0);
-       uatomic_set(&state->last, 0);
+/*
+ * Set health "error" flag.
+ */
+static inline void health_error(struct health_state *state)
+{
+       assert(state);
+       uatomic_or(&state->flags, HEALTH_ERROR);
 }
 
 /*
@@ -84,9 +107,11 @@ static inline void health_reset(struct health_state *state)
 static inline void health_init(struct health_state *state)
 {
        assert(state);
-
-       uatomic_set(&state->last, 0);
-       uatomic_set(&state->current, HEALTH_CODE_VALUE);
+       state->last = 0;
+       state->last_time.tv_sec = 0;
+       state->last_time.tv_nsec = 0;
+       uatomic_set(&state->current, 0);
+       uatomic_set(&state->flags, 0);
 }
 
 int health_check_state(struct health_state *state);