*: remove THREAD_ON macros, add nullity check

The way thread.c is written, a caller who wishes to be able to cancel a
thread or avoid scheduling it twice must keep a reference to the thread.
Typically this is done with a long lived pointer whose value is checked
for null in order to know if the thread is currently scheduled.  The
check-and-schedule idiom is so common that several wrapper macros in
thread.h existed solely to provide it.

This patch removes those macros and adds a new parameter to all
thread_add_* functions which is a pointer to the struct thread * to
store the result of a scheduling call. If the value passed is non-null,
the thread will only be scheduled if the value is null. This helps with
consistency.

A Coccinelle spatch has been used to transform code of the form:

  if (t == NULL)
    t = thread_add_* (...)

to the form

  thread_add_* (..., &t)

The THREAD_ON macros have also been transformed to the underlying
thread.c calls.

Signed-off-by: Quentin Young <qlyoung@cumulusnetworks.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/tests/lib/test_timer_performance.c b/tests/lib/test_timer_performance.c
index a7d09beecc..d1db4fd1bf 100644
--- a/tests/lib/test_timer_performance.c
+++ b/tests/lib/test_timer_performance.c
@@ -57,7 +57,7 @@ int main(int argc, char **argv)
   /* create thread structures so they won't be allocated during the
    * time measurement */
   for (i = 0; i < SCHEDULE_TIMERS; i++)
-    timers[i] = thread_add_timer_msec(master, dummy_func, NULL, 0);
+    timers[i] = thread_add_timer_msec(master, dummy_func, NULL, 0, NULL);
   for (i = 0; i < SCHEDULE_TIMERS; i++)
     thread_cancel(timers[i]);
 
@@ -68,8 +68,8 @@ int main(int argc, char **argv)
       long interval_msec;
 
       interval_msec = prng_rand(prng) % (100 * SCHEDULE_TIMERS);
-      timers[i] = thread_add_timer_msec(master, dummy_func,
-                                        NULL, interval_msec);
+      timers[i] = thread_add_timer_msec(master, dummy_func, NULL,
+                                        interval_msec, NULL);
     }
 
   monotime(&tv_lap);