altos: Rip out 'optimization' in ao_log_scan

Remove premature optimization to avoid re-scanning the flight logs for
the best empty entry.

Signed-off-by: Keith Packard <keithp@keithp.com>

diff --git a/src/ao_log.c b/src/ao_log.c
index 9ca033e1705d52ce6239bff20070335a57e0b5cf..00bb46d32369781b9b9bd15c0996a3e71ab6d745 100644 (file)
--- a/src/ao_log.c
+++ b/src/ao_log.c
@@ -234,9 +234,10 @@ ao_log_flight(uint8_t slot)
 }
 
 static void
 }
 
 static void

-ao_log_scan(void)
+ao_log_scan(void) __reentrant

 {
        uint8_t         log_slot;
 {
        uint8_t         log_slot;

+       uint8_t         log_slots;

        uint8_t         log_avail = 0;
        uint16_t        log_flight;
 
        uint8_t         log_avail = 0;
        uint16_t        log_flight;
 


@@ -244,7 +245,7 @@ ao_log_scan(void)
 
        ao_flight_number = 0;
 
 
        ao_flight_number = 0;
 

-       /* Scan the log space looking for an empty one, and find the biggest flight number */
+       /* Scan the log space looking for the biggest flight number */

        log_slot = 0;
        {
                log_flight = ao_log_flight(log_slot);
        log_slot = 0;
        {
                log_flight = ao_log_flight(log_slot);


@@ -256,8 +257,9 @@ ao_log_scan(void)
                                ao_flight_number = log_flight;
                        }
                } else
                                ao_flight_number = log_flight;
                        }
                } else

-                       log_avail |= 1 << log_slot;
+                       log_avail = 1;

        }
        }

+       log_slots = log_slot + 1;

 
        /* Now look through the log of flight numbers from erase operations and
         * see if the last one is bigger than what we found above
 
        /* Now look through the log of flight numbers from erase operations and
         * see if the last one is bigger than what we found above


@@ -279,25 +281,12 @@ ao_log_scan(void)
         * that we write logs to each spot about the same number of times.
         */
 
         * that we write logs to each spot about the same number of times.
         */
 

-       /* If there are no log slots available, then
-        * do not log the next flight
-        */
-       if (!log_avail) {
-               ao_log_current_pos = 0;
-               ao_log_end_pos = 0;
-       } else {
-               log_slot = ao_flight_number % log_slot;
-               while (!((log_avail & (1 << log_slot)))) {
-                       if ((1 << log_slot) > log_avail)
-                               log_slot = 0;
-                       else
-                               log_slot++;
-               }
-//             ao_log_current_pos = log_slot * ao_config.flight_log_max;
-//             ao_log_end_pos = ao_log_current_pos + ao_config.flight_log_max;
+       /* Find a log slot for the next flight, if available */
+       if (log_avail) {

                ao_log_current_pos = 0;
                ao_log_end_pos = ao_storage_config;
                ao_log_current_pos = 0;
                ao_log_end_pos = ao_storage_config;

-       }
+       } else
+               ao_log_current_pos = ao_log_end_pos = 0;

 
        ao_wakeup(&ao_flight_number);
 }
 
        ao_wakeup(&ao_flight_number);
 }