On Tue, Mar 10, 2015 at 03:45:17PM -0400, Josef Bacik wrote: > From: Dave Chinner <dchinner@xxxxxxxxxx> > > Some filesystems don't use the VFS inode hash and fake the fact they > are hashed so that all the writeback code works correctly. However, > this means the evict() path still tries to remove the inode from the > hash, meaning that the inode_hash_lock() needs to be taken > unnecessarily. Hence under certain workloads the inode_hash_lock can > be contended even if the inode is never actually hashed. > > To avoid this, add an inode opflag to allow inode_hash_remove() to > avoid taking the hash lock on inodes have never actually been > hashed. Why bother with flags, etc. when we could just do static inline bool hlist_fake(struct hlist_node *h) { return h->pprev == &h->next; } > - if (!inode_unhashed(inode)) > + if (!((inode->i_opflags & IOP_NOTHASHED) || inode_unhashed(inode))) and turn this check into if (!inode_unhashed(inode) && !hlist_fake(&inode->i_hash)) instead? -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html