From fd340d0f68cc87badfc9efcb226f23a5428826a0 Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Fri, 11 Jan 2019 10:21:02 -0500 Subject: [PATCH] btrfs: wakeup cleaner thread when adding delayed iput The cleaner thread usually takes care of delayed iputs, with the exception of the btrfs_end_transaction_throttle path. Delaying iputs means we are potentially delaying the eviction of an inode and it's respective space. The cleaner thread only gets woken up every 30 seconds, or when we require space. If there are a lot of inodes that need to be deleted we could induce a serious amount of latency while we wait for these inodes to be evicted. So instead wakeup the cleaner if it's not already awake to process any new delayed iputs we add to the list. If we suddenly need space we will less likely be backed up behind a bunch of inodes that are waiting to be deleted, and we could possibly free space before we need to get into the flushing logic which will save us some latency. Reviewed-by: Filipe Manana Signed-off-by: Josef Bacik Signed-off-by: David Sterba --- fs/btrfs/ctree.h | 3 +++ fs/btrfs/disk-io.c | 3 +++ fs/btrfs/inode.c | 2 ++ 3 files changed, 8 insertions(+) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 34019c8b6158..8b1d06fa222d 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -787,6 +787,9 @@ enum { * main phase. The fs_info::balance_ctl is initialized. */ BTRFS_FS_BALANCE_RUNNING, + + /* Indicate that the cleaner thread is awake and doing something. */ + BTRFS_FS_CLEANER_RUNNING, }; struct btrfs_fs_info { diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 18eefc5b2532..6a2a2a951705 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1682,6 +1682,8 @@ static int cleaner_kthread(void *arg) while (1) { again = 0; + set_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags); + /* Make the cleaner go to sleep early. */ if (btrfs_need_cleaner_sleep(fs_info)) goto sleep; @@ -1728,6 +1730,7 @@ static int cleaner_kthread(void *arg) */ btrfs_delete_unused_bgs(fs_info); sleep: + clear_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags); if (kthread_should_park()) kthread_parkme(); if (kthread_should_stop()) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index b6025b5d0b25..5c349667c761 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -3251,6 +3251,8 @@ void btrfs_add_delayed_iput(struct inode *inode) ASSERT(list_empty(&binode->delayed_iput)); list_add_tail(&binode->delayed_iput, &fs_info->delayed_iputs); spin_unlock(&fs_info->delayed_iput_lock); + if (!test_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags)) + wake_up_process(fs_info->cleaner_kthread); } void btrfs_run_delayed_iputs(struct btrfs_fs_info *fs_info)