stats: add timeout for in_progress access to stat segment
add new api stat_segment_set_timeout_nsec to limit time waiting for vpp
in_progress state.
Change-Id: Ic78a97bc5013d67d7e4bbcc4a6f0ef918f9f9b33
Type: improvement
Signed-off-by: Ole Troan <ot@cisco.com>
diff --git a/src/vpp-api/client/stat_client.h b/src/vpp-api/client/stat_client.h
index 97a21dd..052d969 100644
--- a/src/vpp-api/client/stat_client.h
+++ b/src/vpp-api/client/stat_client.h
@@ -23,6 +23,7 @@
#include <stdint.h>
#include <unistd.h>
#include <vlib/counter_types.h>
+#include <time.h>
#include <stdbool.h>
#include <vpp/stats/stat_segment_shared.h>
@@ -51,6 +52,7 @@
stat_segment_shared_header_t *shared_header;
stat_segment_directory_entry_t *directory_vector;
ssize_t memory_size;
+ uint64_t timeout;
} stat_client_main_t;
extern stat_client_main_t stat_client_main;
@@ -88,17 +90,51 @@
uint64_t epoch;
} stat_segment_access_t;
-static inline void
+/*
+ * Returns 0 on success, -1 on failure (timeout)
+ */
+static inline uint64_t
+_time_now_nsec (void)
+{
+ struct timespec ts;
+ clock_gettime (CLOCK_REALTIME, &ts);
+ return 1e9 * ts.tv_sec + ts.tv_nsec;
+}
+
+static inline int
stat_segment_access_start (stat_segment_access_t * sa,
stat_client_main_t * sm)
{
stat_segment_shared_header_t *shared_header = sm->shared_header;
+ uint64_t max_time;
+
sa->epoch = shared_header->epoch;
- while (shared_header->in_progress != 0)
- ;
+ if (sm->timeout)
+ {
+ max_time = _time_now_nsec () + sm->timeout;
+ while (shared_header->in_progress != 0 && _time_now_nsec () < max_time)
+ ;
+ }
+ else
+ {
+ while (shared_header->in_progress != 0)
+ ;
+ }
sm->directory_vector = (stat_segment_directory_entry_t *)
stat_segment_pointer (sm->shared_header,
sm->shared_header->directory_offset);
+ if (sm->timeout)
+ return _time_now_nsec () < max_time ? 0 : -1;
+ return 0;
+}
+
+/*
+ * set maximum number of nano seconds to wait for in_progress state
+ */
+static inline void
+stat_segment_set_timeout_nsec (stat_client_main_t * sm, uint64_t timeout)
+{
+ sm->timeout = timeout;
}
static inline bool