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See http://www.infradead.org/rpr.html X-Rspamd-Queue-Id: 02347140022 X-Rspam-User: X-Stat-Signature: mg13zwdxf3j385jfp9gjjfomqh5zajjz X-Rspamd-Server: rspam01 X-HE-Tag: 1687883309-517004 X-HE-Meta: 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 qZfg+U8o YIJrHTa2+ruEigoZg5q7CxIaXMkXF0h8JTfUa4cbZI6h3nsTIFEOmo8iKV6kXq77vgvykS2F8Es4OfqrVVXNYuFMdEuowSJSLwwukv/RUBduJOHvk02JjcGMMPe93oZBpyYeJPYXcU1F8JtH6tVs3jX4iO/TGVTCRcB0iMDS4Fj+URsKORskpp17wFxISuPvw/6EmnoVfoaqG1FHzqsXBM/Y2WUlaKDXRbj4ia7XbXL6083zvPI1w+NEQVbDQURKQVw0gQYAPBwcbtgQiLpQK+w8Ih8KUxUiyNOy1UqfH+kHMyxzYmzx95J9mmeTlVsIxd7RsIUL8DWx0yQy+k5b062XiH0OI2FUuGeRMxnym3keoOjQOPwPoOryPS7RYR+SCUYAclZf7tE/2DPqZLMHCQQYZI99u7lBPnr/qch7y76Sum1/u8erqxz41Xw== 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 Tue, Jun 27, 2023 at 04:31:17PM +0100, Matthew Wilcox wrote: > It makes the callers neater. Compare: > > if (!folio) > return writeback_finish(mapping, wbc, false); > vs > if (!folio) { > writeback_finish(mapping, wbc, false); > return NULL; > } > > Similarly for the other two callers. Not sure I agree. See my quickly cooked up patch below. But in the end this completely superficial and I won't complain, do it the way your prefer. > > > > + if (error == AOP_WRITEPAGE_ACTIVATE) { > > > + folio_unlock(folio); > > > + error = 0; > > > > Note there really shouldn't be any need for this in outside of the > > legacy >writepage case. But it might make sense to delay the removal > > until after ->writepage is gone to avoid bugs in conversions. > > ext4_journalled_writepage_callback() still returns > AOP_WRITEPAGE_ACTIVATE, and that's used by a direct call to > write_cache_pages(). Yeah. But that could trivially do the open coded unlock_page. But probably not worth mixing into this series. diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 55832679af2194..07bbbc0dec4d00 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -2360,7 +2360,7 @@ void tag_pages_for_writeback(struct address_space *mapping, } EXPORT_SYMBOL(tag_pages_for_writeback); -static struct folio *writeback_finish(struct address_space *mapping, +static void writeback_finish(struct address_space *mapping, struct writeback_control *wbc, bool done) { folio_batch_release(&wbc->fbatch); @@ -2374,8 +2374,6 @@ static struct folio *writeback_finish(struct address_space *mapping, wbc->done_index = 0; if (wbc->range_cyclic || (wbc->range_whole && wbc->nr_to_write > 0)) mapping->writeback_index = wbc->done_index; - - return NULL; } static struct folio *writeback_get_next(struct address_space *mapping, @@ -2435,20 +2433,19 @@ static struct folio *writeback_get_folio(struct address_space *mapping, { struct folio *folio; - for (;;) { - folio = writeback_get_next(mapping, wbc); - if (!folio) - return writeback_finish(mapping, wbc, false); + while ((folio = writeback_get_next(mapping, wbc))) { wbc->done_index = folio->index; folio_lock(folio); - if (likely(should_writeback_folio(mapping, wbc, folio))) - break; + if (likely(should_writeback_folio(mapping, wbc, folio))) { + trace_wbc_writepage(wbc, inode_to_bdi(mapping->host)); + return folio; + } folio_unlock(folio); } - trace_wbc_writepage(wbc, inode_to_bdi(mapping->host)); - return folio; + writeback_finish(mapping, wbc, false); + return NULL; } struct folio *writeback_iter_init(struct address_space *mapping, @@ -2494,7 +2491,7 @@ struct folio *writeback_iter_next(struct address_space *mapping, wbc->err = error; wbc->done_index = folio->index + folio_nr_pages(folio); - return writeback_finish(mapping, wbc, true); + goto done; } if (!wbc->err) wbc->err = error; @@ -2507,9 +2504,12 @@ struct folio *writeback_iter_next(struct address_space *mapping, * to entering this loop. */ if (--wbc->nr_to_write <= 0 && wbc->sync_mode == WB_SYNC_NONE) - return writeback_finish(mapping, wbc, true); + goto done; return writeback_get_folio(mapping, wbc); +done: + writeback_finish(mapping, wbc, true); + return NULL; } /**