dcache: report a Tasks-RCU quiescent state in dentry_kill()

I am constantly seeing the following warning on Meta's fleet:

  INFO: rcu_tasks detected stalls on tasks:
    native_queued_spin_lock_slowpath
    locked_inode_to_wb_and_lock_list
    inode_io_list_del
    evict
    __dentry_kill
    shrink_dentry_list
    shrink_dcache_tree
    d_invalidate
    btrfs_delete_subvolume
    btrfs_ioctl_snap_destroy
    btrfs_ioctl
    do_syscall_64

dentry_kill() is the common funnel for dentry teardown: dput(),
shrink_dentry_list() and shrink_dcache_tree() all reach it, once per
dentry, and its cond_resched() is the only reschedule point on that path.

cond_resched() is not an RCU-tasks quiescent state.

Use cond_resched_tasks_rcu_qs() so the teardown reports an RCU-tasks
quiescent state as it proceeds.

Fixes: 9c5f1d30199d ("dcache: move cond_resched() into the end of __dentry_kill()")
Cc: stable@vger.kernel.org
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20260918-dcache-task-rcu-qa-v1-1-963ec83e6d0b@debian.org
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>

0 files changed, 0 insertions, 0 deletions