thread: Optionally allow the current time to be passed to

spdk_thread_poll()

This is an optimization if the calling function already knows the
current time.

Change-Id: I1645e08e7475ba6345a44e0f9d4b297a79f6c3c2
Signed-off-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-on: https://review.gerrithub.io/c/443634
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Darek Stojaczyk <dariusz.stojaczyk@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>

examples/bdev/fio_plugin/fio_plugin.c

@@ -649,7 +649,7 @@ spdk_fio_event(struct thread_data *td, int event)
 static size_t
 spdk_fio_poll_thread(struct spdk_fio_thread *fio_thread)
 {
-	return spdk_thread_poll(fio_thread->thread, 0);
+	return spdk_thread_poll(fio_thread->thread, 0, 0);
 }
 
 static int

include/spdk/thread.h

@@ -216,10 +216,12 @@ void spdk_thread_exit(struct spdk_thread *thread);
  * \param thread The thread to process
  * \param max_msgs The maximum number of messages that will be processed.
  *                 Use 0 to process the default number of messages (8).
+ * \param now The current time, in ticks. Optional. If 0 is passed, this
+ *            function may call spdk_get_ticks() to get the current time.
  *
  * \return 1 if work was done. 0 if no work was done. -1 if unknown.
  */
-int spdk_thread_poll(struct spdk_thread *thread, uint32_t max_msgs);
+int spdk_thread_poll(struct spdk_thread *thread, uint32_t max_msgs, uint64_t now);
 
 /**
  * Return the number of ticks until the next timed poller

lib/event/reactor.c

@@ -262,7 +262,7 @@ _spdk_reactor_run(void *arg)
 	while (1) {
 		_spdk_event_queue_run_batch(reactor, thread);
 
-		rc = spdk_thread_poll(thread, 0);
+		rc = spdk_thread_poll(thread, 0, 0);
 
 		/* Determine if the thread can sleep */
 		if (sleep_cycles && rc == 0) {

lib/thread/thread.c

@@ -372,17 +372,20 @@ _spdk_poller_insert_timer(struct spdk_thread *thread, struct spdk_poller *poller
 }
 
 int
-spdk_thread_poll(struct spdk_thread *thread, uint32_t max_msgs)
+spdk_thread_poll(struct spdk_thread *thread, uint32_t max_msgs, uint64_t now)
 {
 	uint32_t msg_count;
 	struct spdk_thread *orig_thread;
 	struct spdk_poller *poller;
 	int rc = 0;
-	uint64_t now;
 
 	orig_thread = _get_thread();
 	tls_thread = thread;
 
+	if (now == 0) {
+		now = spdk_get_ticks();
+	}
+
 	msg_count = _spdk_msg_queue_run_batch(thread, max_msgs);
 	if (msg_count) {
 		rc = 1;
@@ -415,8 +418,6 @@ spdk_thread_poll(struct spdk_thread *thread, uint32_t max_msgs)
 
 	poller = TAILQ_FIRST(&thread->timer_pollers);
 	if (poller) {
-		uint64_t now = spdk_get_ticks();
-
 		if (now >= poller->next_run_tick) {
 			int timer_rc = 0;
 
@@ -443,7 +444,6 @@ spdk_thread_poll(struct spdk_thread *thread, uint32_t max_msgs)
 		}
 	}
 
-	now = spdk_get_ticks();
 	if (rc == 0) {
 		/* Poller status idle */
 		thread->stats.idle_tsc += now - thread->tsc_last;

test/common/lib/ut_multithread.c

@@ -125,7 +125,7 @@ poll_thread(uintptr_t thread_id)
 	original_thread_id = g_thread_id;
 	set_thread(INVALID_THREAD);
 
-	while (spdk_thread_poll(thread->thread, 0) > 0) {
+	while (spdk_thread_poll(thread->thread, 0, 0) > 0) {
 		busy = true;
 	}
 

test/unit/lib/blob/blob.c/blob_ut.c

@@ -779,9 +779,9 @@ blob_snapshot_freeze_io(void)
 	 * Flag 'frozen_io' is set in _spdk_bs_snapshot_freeze_cpl callback.
 	 * Four async I/O operations happen before that. */
 	thread = spdk_get_thread();
-	spdk_thread_poll(thread, 1);
+	spdk_thread_poll(thread, 1, 0);
-	spdk_thread_poll(thread, 1);
+	spdk_thread_poll(thread, 1, 0);
-	spdk_thread_poll(thread, 1);
+	spdk_thread_poll(thread, 1, 0);
 
 	CU_ASSERT(TAILQ_EMPTY(&bs_channel->queued_io));
 

test/unit/lib/blobfs/blobfs_sync_ut/blobfs_sync_ut.c

@@ -146,7 +146,7 @@ _fs_init(void *arg)
 	dev = init_dev();
 	spdk_fs_init(dev, NULL, send_request, fs_op_with_handle_complete, NULL);
 	thread = spdk_get_thread();
-	while (spdk_thread_poll(thread, 0) > 0) {}
+	while (spdk_thread_poll(thread, 0, 0) > 0) {}
 
 	SPDK_CU_ASSERT_FATAL(g_fs != NULL);
 	SPDK_CU_ASSERT_FATAL(g_fs->bdev == dev);
@@ -161,7 +161,7 @@ _fs_unload(void *arg)
 	g_fserrno = -1;
 	spdk_fs_unload(g_fs, fs_op_complete, NULL);
 	thread = spdk_get_thread();
-	while (spdk_thread_poll(thread, 0) > 0) {}
+	while (spdk_thread_poll(thread, 0, 0) > 0) {}
 	CU_ASSERT(g_fserrno == 0);
 	g_fs = NULL;
 }
@@ -235,7 +235,7 @@ cache_write_null_buffer(void)
 	spdk_fs_free_io_channel(channel);
 
 	thread = spdk_get_thread();
-	while (spdk_thread_poll(thread, 0) > 0) {}
+	while (spdk_thread_poll(thread, 0, 0) > 0) {}
 
 	ut_send_request(_fs_unload, NULL);
 }
@@ -265,7 +265,7 @@ fs_create_sync(void)
 	spdk_fs_free_io_channel(channel);
 
 	thread = spdk_get_thread();
-	while (spdk_thread_poll(thread, 0) > 0) {}
+	while (spdk_thread_poll(thread, 0, 0) > 0) {}
 
 	ut_send_request(_fs_unload, NULL);
 }
@@ -306,7 +306,7 @@ cache_append_no_cache(void)
 	spdk_fs_free_io_channel(channel);
 
 	thread = spdk_get_thread();
-	while (spdk_thread_poll(thread, 0) > 0) {}
+	while (spdk_thread_poll(thread, 0, 0) > 0) {}
 
 	ut_send_request(_fs_unload, NULL);
 }
@@ -343,7 +343,7 @@ fs_delete_file_without_close(void)
 	spdk_fs_free_io_channel(channel);
 
 	thread = spdk_get_thread();
-	while (spdk_thread_poll(thread, 0) > 0) {}
+	while (spdk_thread_poll(thread, 0, 0) > 0) {}
 
 	ut_send_request(_fs_unload, NULL);
 
@@ -378,7 +378,7 @@ spdk_thread(void *arg)
 		}
 		pthread_mutex_unlock(&g_mutex);
 
-		spdk_thread_poll(thread, 0);
+		spdk_thread_poll(thread, 0, 0);
 	}
 
 	return NULL;