Eric W. Biederman wrote: > Tejun Heo <htejun@xxxxxxxxx> writes: > >> Hmmm... I think we can live with a bit of complexity in >> sysfs_get_dentry(). It's very well localized and not even long. I have >> been trying hard to untangle sysfs internals from vfs and have a bit of >> resistance against going back. But, then again, if we can achieve >> something better and simpler, why not? > > Right now my real challenge is untangling sysfs_move_dir. In the > case of multiple mounts of the sysfs tree. OIC. Yeah, I guess moving a sd with multiple dentries attached could be pretty difficult. > My practical problem is that I need to hold a lock for the sysfs > dirents and while that lock is held I need to call sysfs_get_dentry > for the destination directory once for each superblock. > > It might be that some kind of reader-writer lock strategy is what > I need to untangle this mess. Rather then making changing to i_mutex. > All I know is at the moment it is taking a lot of code reading and > brain storm to come of with something that is easy to maintain. Just in case, sysfs used to have sysfs_rename_rwsem to protect move/rename against tree walking, which became unnecessary after i_mutex -> sysfs_mutex conversion. Move/rename can use stupid big fat locks if that helps. Good luck. -- tejun _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers