mm: fix polled swap page in

PATCH New Jens Axboe 1 participant 1 message Dec 5, 2018

Subsystems (2)

Memory management MM swap

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Jens Axboe

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2018-12-05 13:49 UTC #0 lore raw

PATCH 1/1 mm: fix polled swap page in

swap_readpage() wants to do polling to bring in pages if asked to, but it doesn't mark the bio as being polled. Additionally, the looping around the blk_poll() check isn't correct - if we get a zero return, we should call io_schedule(), we can't just assume that the bio has completed. The regular bio->bi_private check should be used for that.

Signed-off-by Jens Axboe <[email protected]>

---

mm/page_io.c +3 -1

index 5bdfd21c1bd9..f3455f9f8dc7 100644
@@ -401,6 +401,8 @@ int swap_readpage(struct page *page, bool synchronous)
 	get_task_struct(current);
 	bio->bi_private = current;
 	bio_set_op_attrs(bio, REQ_OP_READ, 0);
+	if (synchronous)
+		bio->bi_opf |= REQ_HIPRI;
 	count_vm_event(PSWPIN);
 	bio_get(bio);
 	qc = submit_bio(bio);

@@ -411,7 +413,7 @@ int swap_readpage(struct page *page, bool synchronous)
 			break;
 
 		if (!blk_poll(disk->queue, qc, true))
-			break;
+			io_schedule();
 	}
 	__set_current_state(TASK_RUNNING);
 	bio_put(bio);

Signature · 1 line

Jens Axboe