Hello, this patch set improves do_get_write_access(), jbd2_journal_get_undo_access(), and jbd2_journal_dirty_metadata() to be completely lockless in case buffer is already part of an appropriate journalling list. First three patches are independent small cleanups so they can go in right away I think. The other two patches *should* improve the situation for frequent bitmap or inode table block updates. But frankly, I haven't been able to come up with a load where I'd see significant contention on update of a single buffer (or it's hidden by a larger lock). Similarly we could see improvements when do_get_write_access() would be waiting for buffer lock because buffer is being written out by checkpointing code. But again I wasn't able to hit this reliably. Ted, you mentioned at Vault you had a setup where frequent do_get_write_access() calls were contending in the revoke code. What was the load exactly? These patches should improve that as well... Honza -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
