Merge remote-tracking branch 'origin/master' into perf/core

Further perf/core patches will depend on:

  d3f7b1bb2040 ("mm/gup: fix gup_fast with dynamic page table folding")

which is already in Linus' tree.

1 files changed, 24 insertions, 12 deletions

diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index 01e2858b5fe3..c73f2e295167 100644
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -226,6 +226,7 @@ struct hib_bio_batch {
 	atomic_t		count;
 	wait_queue_head_t	wait;
 	blk_status_t		error;
+	struct blk_plug		plug;
 };
 
 static void hib_init_batch(struct hib_bio_batch *hb)
@@ -233,6 +234,12 @@ static void hib_init_batch(struct hib_bio_batch *hb)
 	atomic_set(&hb->count, 0);
 	init_waitqueue_head(&hb->wait);
 	hb->error = BLK_STS_OK;
+	blk_start_plug(&hb->plug);
+}
+
+static void hib_finish_batch(struct hib_bio_batch *hb)
+{
+	blk_finish_plug(&hb->plug);
 }
 
 static void hib_end_io(struct bio *bio)
@@ -294,6 +301,10 @@ static int hib_submit_io(int op, int op_flags, pgoff_t page_off, void *addr,
 
 static blk_status_t hib_wait_io(struct hib_bio_batch *hb)
 {
+	/*
+	 * We are relying on the behavior of blk_plug that a thread with
+	 * a plug will flush the plug list before sleeping.
+	 */
 	wait_event(hb->wait, atomic_read(&hb->count) == 0);
 	return blk_status_to_errno(hb->error);
 }
@@ -335,26 +346,23 @@ static int swsusp_swap_check(void)
 {
 	int res;
 
-	res = swap_type_of(swsusp_resume_device, swsusp_resume_block,
-			&hib_resume_bdev);
+	if (swsusp_resume_device)
+		res = swap_type_of(swsusp_resume_device, swsusp_resume_block);
+	else
+		res = find_first_swap(&swsusp_resume_device);
 	if (res < 0)
 		return res;
-
 	root_swap = res;
-	res = blkdev_get(hib_resume_bdev, FMODE_WRITE, NULL);
-	if (res)
-		return res;
+
+	hib_resume_bdev = blkdev_get_by_dev(swsusp_resume_device, FMODE_WRITE,
+			NULL);
+	if (IS_ERR(hib_resume_bdev))
+		return PTR_ERR(hib_resume_bdev);
 
 	res = set_blocksize(hib_resume_bdev, PAGE_SIZE);
 	if (res < 0)
 		blkdev_put(hib_resume_bdev, FMODE_WRITE);
 
-	/*
-	 * Update the resume device to the one actually used,
-	 * so the test_resume mode can use it in case it is
-	 * invoked from hibernate() to test the snapshot.
-	 */
-	swsusp_resume_device = hib_resume_bdev->bd_dev;
 	return res;
 }
 
@@ -561,6 +569,7 @@ static int save_image(struct swap_map_handle *handle,
 		nr_pages++;
 	}
 	err2 = hib_wait_io(&hb);
+	hib_finish_batch(&hb);
 	stop = ktime_get();
 	if (!ret)
 		ret = err2;
@@ -854,6 +863,7 @@ out_finish:
 		pr_info("Image saving done\n");
 	swsusp_show_speed(start, stop, nr_to_write, "Wrote");
 out_clean:
+	hib_finish_batch(&hb);
 	if (crc) {
 		if (crc->thr)
 			kthread_stop(crc->thr);
@@ -1084,6 +1094,7 @@ static int load_image(struct swap_map_handle *handle,
 		nr_pages++;
 	}
 	err2 = hib_wait_io(&hb);
+	hib_finish_batch(&hb);
 	stop = ktime_get();
 	if (!ret)
 		ret = err2;
@@ -1447,6 +1458,7 @@ out_finish:
 	}
 	swsusp_show_speed(start, stop, nr_to_read, "Read");
 out_clean:
+	hib_finish_batch(&hb);
 	for (i = 0; i < ring_size; i++)
 		free_page((unsigned long)page[i]);
 	if (crc) {