From ba89b80268c162eca8f23c5d71eb710d65a132fe Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Wed, 31 Jan 2018 13:56:15 +0800 Subject: [PATCH] btrfs: volumes: Remove the meaningless condition of minimal nr_devs when allocating a chunk When checking the minimal nr_devs, there is one dead and meaningless condition: if (ndevs < devs_increment * sub_stripes || ndevs < devs_min) { ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ This condition is meaningless, @devs_increment has nothing to do with @sub_stripes. In fact, in btrfs_raid_array[], profile with sub_stripes larger than 1 (RAID10) already has the @devs_increment set to 2. So no need to multiple it by @sub_stripes. And above condition is also dead. For RAID10, @devs_increment * @sub_stripes equals 4, which is also the @devs_min of RAID10. For other profiles, @sub_stripes is always 1, and since @ndevs is rounded down to @devs_increment, the condition will always be true. Remove the meaningless condition to make later reader wander less. Signed-off-by: Qu Wenruo Reviewed-by: Nikolay Borisov Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/volumes.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 1e72357bdfa8..dcc2b486b2c5 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -4837,13 +4837,12 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans, /* round down to number of usable stripes */ ndevs = round_down(ndevs, devs_increment); - if (ndevs < devs_increment * sub_stripes || ndevs < devs_min) { + if (ndevs < devs_min) { ret = -ENOSPC; if (btrfs_test_opt(info, ENOSPC_DEBUG)) { btrfs_debug(info, "%s: not enough devices with free space: have=%d minimum required=%d", - __func__, ndevs, min(devs_min, - devs_increment * sub_stripes)); + __func__, ndevs, devs_min); } goto error; }