On Thu, Dec 17, 2020 at 07:05:37PM +0000, Joao Martins wrote:
> > No reason not to fix set_page_dirty_lock() too while you are here.
>
> The wack of atomics you mentioned earlier you referred to, I suppose it
> ends being account_page_dirtied(). See partial diff at the end.
Well, even just eliminating the lock_page, page_mapping, PageDirty,
etc is already a big win.
If mapping->a_ops->set_page_dirty() needs to be called multiple times
on the head page I'd probably just suggest:
while (ntails--)
rc |= (*spd)(head);
At least as a start.
If you have workloads that have page_mapping != NULL then look at
another series to optimze that. Looks a bit large though given the
number of places implementing set_page_dirty
I think the current reality is calling set_page_dirty on an actual
file system is busted anyhow, so I think mapping is generally going to
be NULL here?
Jason
