Commit c65060ad authored by Namhyung Kim's avatar Namhyung Kim Committed by NeilBrown
Browse files

md/raid10: share pages between read and write bio's during recovery 



When performing a recovery, only first 2 slots in r10_bio are in use,
for read and write respectively. However all of pages in the write bio
are never used and just replaced to read bio's when the read completes.

Get rid of those unused pages and share read pages properly.

Signed-off-by: default avatarNamhyung Kim <namhyung@gmail.com>
Signed-off-by: default avatarNeilBrown <neilb@suse.de>
parent 778ca018

drivers/md/raid10.c

+12 −11
Original line number Diff line number Diff line
@@ -123,6 +123,13 @@ static void * r10buf_pool_alloc(gfp_t gfp_flags, void *data) 
	for (j = 0 ; j < nalloc; j++) {

		bio = r10_bio->devs[j].bio;

		for (i = 0; i < RESYNC_PAGES; i++) {

			if (j == 1 && !test_bit(MD_RECOVERY_SYNC,

						&conf->mddev->recovery)) {

				/* we can share bv_page's during recovery */

				struct bio *rbio = r10_bio->devs[0].bio;

				page = rbio->bi_io_vec[i].bv_page;

				get_page(page);

			} else

				page = alloc_page(gfp_flags);

			if (unlikely(!page))

				goto out_free_pages;
@@ -1360,20 +1367,14 @@ done: 
static void recovery_request_write(mddev_t *mddev, r10bio_t *r10_bio)

{

	conf_t *conf = mddev->private;

	int i, d;

	struct bio *bio, *wbio;



	int d;

	struct bio *wbio;



	/* move the pages across to the second bio

	/*

	 * share the pages with the first bio

	 * and submit the write request

	 */

	bio = r10_bio->devs[0].bio;

	wbio = r10_bio->devs[1].bio;

	for (i=0; i < wbio->bi_vcnt; i++) {

		struct page *p = bio->bi_io_vec[i].bv_page;

		bio->bi_io_vec[i].bv_page = wbio->bi_io_vec[i].bv_page;

		wbio->bi_io_vec[i].bv_page = p;

	}

	d = r10_bio->devs[1].devnum;



	atomic_inc(&conf->mirrors[d].rdev->nr_pending);

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