On Fri, Feb 23, 2018 at 12:50:25AM +0100, John Ogness wrote: > Avoid the trylock loop by using dentry_kill(). When killing dentries > from the dispose list, it is very similar to killing a dentry in > dput(). The difference is that dput() expects to be the last user of > the dentry (refcount=1) and will deref whereas shrink_dentry_list() > expects there to be no user (refcount=0). In order to handle both > situations with the same code, move the deref code from dentry_kill() > into a new wrapper function dentry_put_kill(), which can be used > by previous dentry_kill() users. Then shrink_dentry_list() can use > the dentry_kill() to cleanup the dispose list. > > This also has the benefit that the locking order is now the same. > First the inode is locked, then the parent. Current code moves the sucker to the end of list in that case; I'm not at all sure that what you are doing will improve the situation at all... You *still* have a trylock loop there - only it keeps banging at the same dentry instead of going through the rest first...
