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See http://www.infradead.org/rpr.html X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 349B140016 X-Stat-Signature: s78sekdewao4wwqdfs1htbrj1hnkpo58 X-HE-Tag: 1678980251-699570 X-HE-Meta: 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 DjS4Wo5c CPlBWgXngFz6DOJL1yh1aHV+xaSJV06EEiwnCFHM18TLo4VhL5v1zjElSy9c6CoEd2HxtoIjn5bs8FHPAuoXJ+M+ZqnyKJTHdHQWmlYPhZvs85rj+0g5C8Ijv+cB2Bs8x54hVH6Riq2y85VPJ8VENVL36S1mDQZG5FVilC8ievIad7K3vnf/bSqewranUio/ANG++5F5XVyG4GE4t1Jrnyq8F/YHhc8ULXaWeAeDuw78xchdA03huasueeLOzMBzLXD9KdtuMKWAcXkBwtfBENwIg0utBB4Llv+QC2MW9Bzcz4Sev5KQd1nLOU/f4BKLeXcfzGhzGrLEybaNZRRIPG7ErhnzP309mN3wHMDtRVB1reg3O+p/9zeIzKgMsgdYqX+HqNr6752ove1KVuACviHOM3rj4DEgS6U98UPK5liqQa60nORfDzmgXyMPj98gCYQ1KfcvDO9Znc1M= 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 Thu, Mar 16, 2023 at 11:04:54AM +0100, Pankaj Raghav wrote: > It looks like this endio function is called when alloc_page is used (for > partial IO) to trigger writeback from the user space `echo "idle" > > /sys/block/zram0/writeback`. Yes. > I don't understand when you say the harm might not be horrible if we don't > call folio_endio here. Do you think it is just safe to remove the call to > folio_endio function? I suspect so. It doesn't seem like the involved pages are ever locked or have the writeback set, so it should be fine. > + while ((folio = readahead_folio(rac))) { > + folio_clear_uptodate(folio); > + folio_set_error(folio); > + folio_unlock(folio); > + } > + return; > + } > + > + while ((folio = readahead_folio(rac))) { > + folio_mark_uptodate(folio); > + folio_unlock(folio); > } > } Looks good. > @@ -59,7 +59,8 @@ static void mpage_end_io(struct bio *bio) > static struct bio *mpage_bio_submit(struct bio *bio) > { > - bio->bi_end_io = mpage_end_io; > + bio->bi_end_io = (op_is_write(bio_op(bio))) ? mpage_write_end_io : > + mpage_read_end_io; > guard_bio_eod(bio); > submit_bio(bio); > return NULL; > And mpage_{write,read}_end_io will iterate over the folio and call the > respective functions. Yes, although I'd do it with a good old if/else and with less braces. It might make sense to split mpage_bio_submit as well, though.