Re: [PATCH v14 082/138] mm/lru: Convert __pagevec_lru_add_fn to take a folio

From: Matthew Wilcox
Date: Sun Aug 15 2021 - 22:21:40 EST


On Tue, Aug 10, 2021 at 10:44:27PM +0100, David Howells wrote:
> Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> wrote:
>
> > * looking at the same page) and the evictable page will be stranded
> > * in an unevictable LRU.
>
> Does that need converting to say 'folio'?

Changed the parapgraph (passed it through fmt too)

* if '#1' does not observe setting of PG_lru by '#0' and
* fails isolation, the explicit barrier will make sure that
* folio_evictable check will put the folio on the correct
* LRU. Without smp_mb(), folio_set_lru() can be reordered
* after folio_test_mlocked() check and can make '#1' fail the
* isolation of the folio whose mlocked bit is cleared (#0 is
* also looking at the same folio) and the evictable folio will
* be stranded on an unevictable LRU.

> Other than that:
>
> Reviewed-by: David Howells <dhowells@xxxxxxxxxx>
>