igt_core: Refactor igt_stop_helper() to use igt_wait_helper()

Reduce code duplication as the igt_stop_helper can reuse
igt_wait_helper() to replace its own waiting routine.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

diff --git a/lib/igt_core.c b/lib/igt_core.c
index 0a2ddad..1287ff6 100644 (file)
--- a/lib/igt_core.c
+++ b/lib/igt_core.c
@@ -843,56 +843,45 @@ bool __igt_fork_helper(struct igt_helper_process *proc)
 }
 
 /**
- * igt_stop_helper:
+ * igt_wait_helper:
  * @proc: #igt_helper_process structure
  *
- * Terminates a helper process. It is an error to call this on a helper process
- * which hasn't been spawned yet.
+ * Joins a helper process. It is an error to call this on a helper process which
+ * hasn't been spawned yet.
  */
-void igt_stop_helper(struct igt_helper_process *proc)
+int igt_wait_helper(struct igt_helper_process *proc)
 {
-       int status, ret;
+       int status = -1;
 
        assert(proc->running);
 
-       ret = kill(proc->pid,
-                  proc->use_SIGKILL ? SIGKILL : SIGTERM);
-       assert(ret == 0);
-
-       while (waitpid(proc->pid, &status, 0) == -1 &&
-              errno == EINTR)
-               ;
-       igt_assert(WIFSIGNALED(status) &&
-                  WTERMSIG(status) == (proc->use_SIGKILL ? SIGKILL : SIGTERM));
+       waitpid(proc->pid, &status, WNOHANG);
 
        proc->running = false;
 
        helper_process_pids[proc->id] = -1;
        helper_process_count--;
+
+       return status;
 }
 
 /**
- * igt_wait_helper:
+ * igt_stop_helper:
  * @proc: #igt_helper_process structure
  *
- * Joins a helper process. It is an error to call this on a helper process which
- * hasn't been spawned yet.
+ * Terminates a helper process. It is an error to call this on a helper process
+ * which hasn't been spawned yet.
  */
-void igt_wait_helper(struct igt_helper_process *proc)
+void igt_stop_helper(struct igt_helper_process *proc)
 {
        int status;
 
-       assert(proc->running);
-
-       while (waitpid(proc->pid, &status, 0) == -1 &&
-              errno == EINTR)
-               ;
-       igt_assert(WIFEXITED(status) && WEXITSTATUS(status) == 0);
-
-       proc->running = false;
+       /* failure here means the pid is already dead and so waiting is safe */
+       kill(proc->pid, proc->use_SIGKILL ? SIGKILL : SIGTERM);
 
-       helper_process_pids[proc->id] = -1;
-       helper_process_count--;
+       status = igt_wait_helper(proc);
+       assert(WIFSIGNALED(status) &&
+              WTERMSIG(status) == (proc->use_SIGKILL ? SIGKILL : SIGTERM));
 }
 
 static void children_exit_handler(int sig)

diff --git a/lib/igt_core.h b/lib/igt_core.h
index 0e84e98..2838cb1 100644 (file)
--- a/lib/igt_core.h
+++ b/lib/igt_core.h
@@ -420,7 +420,7 @@ bool __igt_fork_helper(struct igt_helper_process *proc);
  */
 #define igt_fork_helper(proc) \
        for (; __igt_fork_helper(proc); exit(0))
-void igt_wait_helper(struct igt_helper_process *proc);
+int igt_wait_helper(struct igt_helper_process *proc);
 void igt_stop_helper(struct igt_helper_process *proc);
 
 /* exit handler code */

diff --git a/tests/pm_rps.c b/tests/pm_rps.c
index 96fec99..8593e36 100644 (file)
--- a/tests/pm_rps.c
+++ b/tests/pm_rps.c
@@ -253,8 +253,12 @@ static void load_helper_run(enum load load)
 
 static void load_helper_stop(void)
 {
+       int status;
+
        kill(lh.igt_proc.pid, SIGUSR1);
-       igt_wait_helper(&lh.igt_proc);
+       status = igt_wait_helper(&lh.igt_proc);
+
+       igt_assert(WIFSIGNALED(status) && WTERMSIG(status) == SIGUSR1);
 }
 
 static void load_helper_init(void)