Simplification and optimisation of jobs

It comes from the use of this module that it can
be simplified to only get 1 argument. It reduces
either the complexity of the code and the time spent
in job management.

It optimise how normal jobs are called (not intermediate
function).

Also factorisation and simplification of synchronous
enter/call.

Change-Id: Id60dd2363fee2b007b4557430659faf733d2179d
Signed-off-by: José Bollo <jose.bollo@iot.bzh>

2 files changed, 80 insertions, 168 deletions

diff --git a/src/jobs.c b/src/jobs.c
index 8f51cc99..8725d00e 100644
--- a/src/jobs.c
+++ b/src/jobs.c
@@ -44,7 +44,7 @@
 #define EVENT_TIMEOUT_CHILD	((uint64_t)10000)
 
 /** Internal shortcut for callback */
-typedef void (*job_cb_t)(int, void*, void *, void*);
+typedef void (*job_cb_t)(int, void*);
 
 /** Description of a pending job */
 struct job
@@ -52,9 +52,7 @@ struct job
 	struct job *next;    /**< link to the next job enqueued */
 	void *group;         /**< group of the request */
 	job_cb_t callback;   /**< processing callback */
-	void *arg1;          /**< first arg */
-	void *arg2;          /**< second arg */
-	void *arg3;          /**< third arg */
+	void *arg;           /**< argument */
 	int timeout;         /**< timeout in second for processing the request */
 	unsigned blocked: 1; /**< is an other request blocking this one ? */
 	unsigned dropped: 1; /**< is removed ? */
@@ -87,10 +85,16 @@ struct thread
  */
 struct sync
 {
-	void (*callback)(int, void*);	/**< the synchrnous callback */
-	void *arg;			/**< the argument of the callback */
+	struct thread thread;	/**< thread loop data */
+	union {
+		void (*callback)(int, void*);	/**< the synchronous callback */
+		void (*enter)(int signum, void *closure, struct jobloop *jobloop);
+				/**< the entering synchronous routine */
+	};
+	void *arg;		/**< the argument of the callback */
 };
 
+
 /* synchronisation of threads */
 static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
 static pthread_cond_t  cond = PTHREAD_COND_INITIALIZER;
@@ -116,18 +120,14 @@ static struct job *free_jobs;
  * @param group    the group of the job
  * @param timeout  the timeout of the job (0 if none)
  * @param callback the function that achieves the job
- * @param arg1     the first argument of the callback
- * @param arg2     the second argument of the callback
- * @param arg3     the third argument of the callback
+ * @param arg      the argument of the callback
  * @return the created job unblock or NULL when no more memory
  */
 static struct job *job_create(
 		void *group,
 		int timeout,
 		job_cb_t callback,
-		void *arg1,
-		void *arg2,
-		void *arg3)
+		void *arg)
 {
 	struct job *job;
 
@@ -149,9 +149,7 @@ static struct job *job_create(
 	job->group = group;
 	job->timeout = timeout;
 	job->callback = callback;
-	job->arg1 = arg1;
-	job->arg2 = arg2;
-	job->arg3 = arg3;
+	job->arg = arg;
 	job->blocked = 0;
 	job->dropped = 0;
 end:
@@ -246,22 +244,6 @@ static inline void job_release(struct job *job)
 }
 
 /**
- * Monitored normal callback for a job.
- * This function is called by the monitor
- * to run the job when the safe environment
- * is set.
- * @param signum 0 on normal flow or the number
- *               of the signal that interrupted the normal
- *               flow
- * @param arg     the job to run
- */
-static void job_call(int signum, void *arg)
-{
-	struct job *job = arg;
-	job->callback(signum, job->arg1, job->arg2, job->arg3);
-}
-
-/**
  * Monitored cancel callback for a job.
  * This function is called by the monitor
  * to cancel the job when the safe environment
@@ -273,7 +255,8 @@ static void job_call(int signum, void *arg)
  */
 static void job_cancel(int signum, void *arg)
 {
-	job_call(SIGABRT, arg);
+	struct job *job = arg;
+	job->callback(SIGABRT, job->arg);
 }
 
 /**
@@ -338,7 +321,7 @@ static void thread_run(volatile struct thread *me)
 
 			/* run the job */
 			pthread_mutex_unlock(&mutex);
-			sig_monitor(job->timeout, job_call, job);
+			sig_monitor(job->timeout, job->callback, job->arg);
 			pthread_mutex_lock(&mutex);
 
 			/* release the run job */
@@ -422,29 +405,7 @@ static int start_one_thread()
 }
 
 /**
- * Queues a new asynchronous job represented by 'callback'
- * for the 'group' and the 'timeout'.
- * Jobs are queued FIFO and are possibly executed in parallel
- * concurrently except for job of the same group that are
- * executed sequentially in FIFO order.
- * @param group    The group of the job or NULL when no group.
- * @param timeout  The maximum execution time in seconds of the job
- *                 or 0 for unlimited time.
- * @param callback The function to execute for achieving the job.
- *                 Its first parameter is either 0 on normal flow
- *                 or the signal number that broke the normal flow.
- * @return 0 in case of success or -1 in case of error
- */
-int jobs_queue0(
-		void *group,
-		int timeout,
-		void (*callback)(int signum))
-{
-	return jobs_queue3(group, timeout, (job_cb_t)callback, NULL, NULL, NULL);
-}
-
-/**
- * Queues a new asynchronous job represented by 'callback' and 'arg1'
+ * Queues a new asynchronous job represented by 'callback' and 'arg'
  * for the 'group' and the 'timeout'.
  * Jobs are queued FIFO and are possibly executed in parallel
  * concurrently except for job of the same group that are
@@ -466,64 +427,6 @@ int jobs_queue(
 		void (*callback)(int, void*),
 		void *arg)
 {
-	return jobs_queue3(group, timeout, (job_cb_t)callback, arg, NULL, NULL);
-}
-
-/**
- * Queues a new asynchronous job represented by 'callback' and 'arg[12]'
- * for the 'group' and the 'timeout'.
- * Jobs are queued FIFO and are possibly executed in parallel
- * concurrently except for job of the same group that are
- * executed sequentially in FIFO order.
- * @param group    The group of the job or NULL when no group.
- * @param timeout  The maximum execution time in seconds of the job
- *                 or 0 for unlimited time.
- * @param callback The function to execute for achieving the job.
- *                 Its first parameter is either 0 on normal flow
- *                 or the signal number that broke the normal flow.
- *                 The remaining parameters are the parameters 'arg[12]'
- *                 given here.
- * @param arg1     The second argument for 'callback'
- * @param arg2     The third argument for 'callback'
- * @return 0 in case of success or -1 in case of error
- */
-int jobs_queue2(
-		void *group,
-		int timeout,
-		void (*callback)(int, void*, void*),
-		void *arg1,
-		void *arg2)
-{
-	return jobs_queue3(group, timeout, (job_cb_t)callback, arg1, arg2, NULL);
-}
-
-/**
- * Queues a new asynchronous job represented by 'callback' and 'arg[123]'
- * for the 'group' and the 'timeout'.
- * Jobs are queued FIFO and are possibly executed in parallel
- * concurrently except for job of the same group that are
- * executed sequentially in FIFO order.
- * @param group    The group of the job or NULL when no group.
- * @param timeout  The maximum execution time in seconds of the job
- *                 or 0 for unlimited time.
- * @param callback The function to execute for achieving the job.
- *                 Its first parameter is either 0 on normal flow
- *                 or the signal number that broke the normal flow.
- *                 The remaining parameters are the parameters 'arg[123]'
- *                 given here.
- * @param arg1     The second argument for 'callback'
- * @param arg2     The third argument for 'callback'
- * @param arg3     The forth argument for 'callback'
- * @return 0 in case of success or -1 in case of error
- */
-int jobs_queue3(
-		void *group,
-		int timeout,
-		void (*callback)(int, void*, void *, void*),
-		void *arg1,
-		void *arg2,
-		void *arg3)
-{
 	const char *info;
 	struct job *job;
 	int rc;
@@ -531,7 +434,7 @@ int jobs_queue3(
 	pthread_mutex_lock(&mutex);
 
 	/* allocates the job */
-	job = job_create(group, timeout, callback, arg1, arg2, arg3);
+	job = job_create(group, timeout, callback, arg);
 	if (!job) {
 		errno = ENOMEM;
 		info = "out of memory";
@@ -574,35 +477,45 @@ error:
 }
 
 /**
- * Enter a synchronisation point: activates the job given by 'callback'
- * and 'closure' using 'group' and 'timeout' to control sequencing and
- * execution time.
- * @param group the group for sequencing jobs
- * @param timeout the time in seconds allocated to the job
- * @param callback the callback that will handle the job.
- *                 it receives 3 parameters: 'signum' that will be 0
- *                 on normal flow or the catched signal number in case
- *                 of interrupted flow, the context 'closure' as given and
- *                 a 'jobloop' reference that must be used when the job is
- *                 terminated to unlock the current execution flow.
- * @param closure the context completion closure for the callback
- * @return 0 on success or -1 in case of error
+ * Internal helper function for 'jobs_enter'.
+ * @see jobs_enter, jobs_leave
  */
-int jobs_enter(
+static void enter_cb(int signum, void *closure)
+{
+	struct sync *sync = closure;
+	sync->enter(signum, sync->arg, (void*)&sync->thread);
+}
+
+/**
+ * Internal helper function for 'jobs_call'.
+ * @see jobs_call
+ */
+static void call_cb(int signum, void *closure)
+{
+	struct sync *sync = closure;
+	sync->callback(signum, sync->arg);
+	jobs_leave((void*)&sync->thread);
+}
+
+/**
+ * Internal helper for synchronous jobs. It enters
+ * a new thread loop for evaluating the given job
+ * as recorded by the couple 'sync_cb' and 'sync'.
+ * @see jobs_call, jobs_enter, jobs_leave
+ */
+static int do_sync(
 		void *group,
 		int timeout,
-		void (*callback)(int signum, void *closure, struct jobloop *jobloop),
-		void *closure
+		void (*sync_cb)(int signum, void *closure),
+		struct sync *sync
 )
 {
-	
 	struct job *job;
-	struct thread me;
 
 	pthread_mutex_lock(&mutex);
 
 	/* allocates the job */
-	job = job_create(group, timeout, (job_cb_t)callback, closure, &me, NULL);
+	job = job_create(group, timeout, sync_cb, sync);
 	if (!job) {
 		ERROR("out of memory");
 		errno = ENOMEM;
@@ -614,12 +527,41 @@ int jobs_enter(
 	job_add(job);
 
 	/* run until stopped */
-	thread_run(&me);
+	thread_run(&sync->thread);
 	pthread_mutex_unlock(&mutex);
 	return 0;
 }
 
 /**
+ * Enter a synchronisation point: activates the job given by 'callback'
+ * and 'closure' using 'group' and 'timeout' to control sequencing and
+ * execution time.
+ * @param group the group for sequencing jobs
+ * @param timeout the time in seconds allocated to the job
+ * @param callback the callback that will handle the job.
+ *                 it receives 3 parameters: 'signum' that will be 0
+ *                 on normal flow or the catched signal number in case
+ *                 of interrupted flow, the context 'closure' as given and
+ *                 a 'jobloop' reference that must be used when the job is
+ *                 terminated to unlock the current execution flow.
+ * @param arg the argument to the callback
+ * @return 0 on success or -1 in case of error
+ */
+int jobs_enter(
+		void *group,
+		int timeout,
+		void (*callback)(int signum, void *closure, struct jobloop *jobloop),
+		void *closure
+)
+{
+	struct sync sync;
+
+	sync.enter = callback;
+	sync.arg = closure;
+	return do_sync(group, timeout, enter_cb, &sync);
+}
+
+/**
  * Unlocks the execution flow designed by 'jobloop'.
  * @param jobloop indication of the flow to unlock
  * @return 0 in case of success of -1 on error
@@ -644,17 +586,6 @@ int jobs_leave(struct jobloop *jobloop)
 }
 
 /**
- * Internal helper function for 'jobs_call'.
- * @see jobs_call, jobs_enter, jobs_leave
- */
-static void call_cb(int signum, void *closure, struct jobloop *jobloop)
-{
-	struct sync *sync = closure;
-	sync->callback(signum, sync->arg);
-	jobs_leave(jobloop);
-}
-
-/**
  * Calls synchronously the job represented by 'callback' and 'arg1'
  * for the 'group' and the 'timeout' and waits for its completion.
  * @param group    The group of the job or NULL when no group.
@@ -678,7 +609,8 @@ int jobs_call(
 
 	sync.callback = callback;
 	sync.arg = arg;
-	return jobs_enter(group, timeout, call_cb, &sync);
+
+	return do_sync(group, timeout, call_cb, &sync);
 }
 
 /**
@@ -801,7 +733,7 @@ int jobs_start(int allowed_count, int start_count, int waiter_count, void (*star
 	}
 
 	/* queue the start job */
-	job = job_create(NULL, 0, (job_cb_t)start, NULL, NULL, NULL);
+	job = job_create(NULL, 0, (job_cb_t)start, NULL);
 	if (!job) {
 		ERROR("out of memory");
 		errno = ENOMEM;
diff --git a/src/jobs.h b/src/jobs.h
index a98b27ad..49f45dd5 100644
--- a/src/jobs.h
+++ b/src/jobs.h
@@ -20,32 +20,12 @@
 struct sd_event;
 struct jobloop;
 
-extern int jobs_queue0(
-		void *group,
-		int timeout,
-		void (*callback)(int signum));
-
 extern int jobs_queue(
 		void *group,
 		int timeout,
 		void (*callback)(int signum, void* arg),
 		void *arg);
 
-extern int jobs_queue2(
-		void *group,
-		int timeout,
-		void (*callback)(int signum, void* arg1, void *arg2),
-		void *arg1,
-		void *arg2);
-
-extern int jobs_queue3(
-		void *group,
-		int timeout,
-		void (*callback)(int signum, void* arg1, void *arg2, void *arg3),
-		void *arg1,
-		void *arg2,
-		void *arg3);
-
 extern int jobs_enter(
 		void *group,
 		int timeout,