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See http://www.infradead.org/rpr.html X-Rspamd-Queue-Id: D21194000B X-Rspam-User: X-Rspamd-Server: rspam02 X-Stat-Signature: z3xwnd1fz3doou71t3s7xws8zhagkh7u X-HE-Tag: 1687839374-322713 X-HE-Meta: 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 NQDfOvqQ 9QNNag7w84aptg5i/Z7b4ytm/ZOlHqyaef5zY3JhBU5UInbDsLCtTefv2FsgTCWa0NEGm5qEXDxZOlfggMKEJe0d2jiquRFUB7poZT7t6ynYwLJrdAqo21f9tbkAhIdmmm75e94z/Plmkhade/QKCzAP4150UNqlOzZVOCeshI2FKU4Tl9OcF1gYwvSg7O9YZEU9x2zEIdaOinggYOdxAdELRk4sQ0Pw70y1mvwtP0FLSvCn9e4TDfcncto03GaXoEjdIltw+9TcMCWhRY2v/55i4Y1hIiEtKWAIHkfFKBCRfxg+INv7XJBeMzj4LJromarbOM7oY7KtK4CbHE5T6B951rsiyC3hIVGyzq7eI96d+t3DbVMW4sq2Trhoe+vQVbX3FNXcN3gtOsJs/URh+kZQs7HKYedAuTdTBTSB9LOLYM4TaZvThDjL/Tw== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Jun 26, 2023 at 06:35:13PM +0100, Matthew Wilcox (Oracle) wrote: > Collapse the two nested loops into one. This is needed as a step > towards turning this into an iterator. > --- > mm/page-writeback.c | 94 ++++++++++++++++++++++----------------------- > 1 file changed, 47 insertions(+), 47 deletions(-) > > diff --git a/mm/page-writeback.c b/mm/page-writeback.c > index 54f2972dab45..68f28eeb15ed 100644 > --- a/mm/page-writeback.c > +++ b/mm/page-writeback.c > @@ -2461,6 +2461,7 @@ int write_cache_pages(struct address_space *mapping, > void *data) > { > int error; > + int i = 0; > > if (wbc->range_cyclic) { > wbc->index = mapping->writeback_index; /* prev offset */ > @@ -2478,65 +2479,64 @@ int write_cache_pages(struct address_space *mapping, > folio_batch_init(&wbc->fbatch); > wbc->err = 0; > > + for (;;) { > + struct folio *folio; > > + if (i == wbc->fbatch.nr) { > + writeback_get_batch(mapping, wbc); > + i = 0; > + } > if (wbc->fbatch.nr == 0) > break; > + folio = wbc->fbatch.folios[i++]; Did you consider moving what is currently the "i" local variable into strut writeback_control as well? Then writeback_get_batch could return the current folio, and we could hae a much nicer loop here by moving all of the above into writeback_get_batch: while ((folio = writeback_get_batch(mapping, wbc))) { (and yes, writeback_get_batch probably needs a better name with that)