From 4fc6441aac75893b4f32415f693d001f290d7d5b Mon Sep 17 00:00:00 2001 From: Anand Jain Date: Tue, 13 Jun 2017 17:05:41 +0800 Subject: [PATCH] btrfs: wait part of the write_dev_flush() can be separated out Submit and wait parts of write_dev_flush() can be split into two separate functions for better readability. Signed-off-by: Anand Jain Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/disk-io.c | 59 ++++++++++++++++++++++++---------------------- 1 file changed, 31 insertions(+), 28 deletions(-) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 528eef955060..2b00ebff13f8 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -3488,37 +3488,16 @@ static void btrfs_end_empty_barrier(struct bio *bio) } /* - * trigger flushes for one the devices. If you pass wait == 0, the flushes are - * sent down. With wait == 1, it waits for the previous flush. - * - * any device where the flush fails with eopnotsupp are flagged as not-barrier - * capable + * Submit a flush request to the device if it supports it. Error handling is + * done in the waiting counterpart. */ -static int write_dev_flush(struct btrfs_device *device, int wait) +static void write_dev_flush(struct btrfs_device *device) { struct request_queue *q = bdev_get_queue(device->bdev); struct bio *bio; - int ret = 0; if (!test_bit(QUEUE_FLAG_WC, &q->queue_flags)) - return 0; - - if (wait) { - bio = device->flush_bio; - wait_for_completion(&device->flush_wait); - - if (bio->bi_error) { - ret = bio->bi_error; - btrfs_dev_stat_inc_and_print(device, - BTRFS_DEV_STAT_FLUSH_ERRS); - } - - /* drop the reference from the wait == 0 run */ - bio_put(bio); - device->flush_bio = NULL; - - return ret; - } + return; /* * one reference for us, and we leave it for the @@ -3535,8 +3514,32 @@ static int write_dev_flush(struct btrfs_device *device, int wait) bio_get(bio); btrfsic_submit_bio(bio); +} - return 0; +/* + * If the flush bio has been submitted by write_dev_flush, wait for it. + */ +static int wait_dev_flush(struct btrfs_device *device) +{ + int ret = 0; + struct bio *bio = device->flush_bio; + + if (!bio) + return 0; + + wait_for_completion(&device->flush_wait); + + if (bio->bi_error) { + ret = bio->bi_error; + btrfs_dev_stat_inc_and_print(device, + BTRFS_DEV_STAT_FLUSH_ERRS); + } + + /* drop the reference from the wait == 0 run */ + bio_put(bio); + device->flush_bio = NULL; + + return ret; } static int check_barrier_error(struct btrfs_fs_devices *fsdevs) @@ -3577,7 +3580,7 @@ static int barrier_all_devices(struct btrfs_fs_info *info) if (!dev->in_fs_metadata || !dev->writeable) continue; - write_dev_flush(dev, 0); + write_dev_flush(dev); dev->last_flush_error = 0; } @@ -3592,7 +3595,7 @@ static int barrier_all_devices(struct btrfs_fs_info *info) if (!dev->in_fs_metadata || !dev->writeable) continue; - ret = write_dev_flush(dev, 1); + ret = wait_dev_flush(dev); if (ret) { dev->last_flush_error = ret; errors_wait++; -- 2.20.1