Remove useless "while" loop. If the condition ci.sector_count && !error is true, we go to a branch that ends with "break". If this condition is false, the "while" loop will not be executed again. So, the loop can't be executed more than once.
Signed-off-by: Mikulas Patocka <[email protected]> --- drivers/md/dm.c | 57 ++++++++++++++++++++++++++------------------------------ 1 file changed, 27 insertions(+), 30 deletions(-) Index: linux-2.6/drivers/md/dm.c =================================================================== --- linux-2.6.orig/drivers/md/dm.c 2021-02-23 17:18:54.000000000 +0100 +++ linux-2.6/drivers/md/dm.c 2021-02-26 19:10:31.000000000 +0100 @@ -1584,38 +1584,35 @@ static blk_qc_t __split_and_process_bio( } else { ci.bio = bio; ci.sector_count = bio_sectors(bio); - while (ci.sector_count && !error) { - error = __split_and_process_non_flush(&ci); - if (ci.sector_count && !error) { - /* - * Remainder must be passed to submit_bio_noacct() - * so that it gets handled *after* bios already submitted - * have been completely processed. - * We take a clone of the original to store in - * ci.io->orig_bio to be used by end_io_acct() and - * for dec_pending to use for completion handling. - */ - struct bio *b = bio_split(bio, bio_sectors(bio) - ci.sector_count, - GFP_NOIO, &md->queue->bio_split); - ci.io->orig_bio = b; + error = __split_and_process_non_flush(&ci); + if (ci.sector_count && !error) { + /* + * Remainder must be passed to submit_bio_noacct() + * so that it gets handled *after* bios already submitted + * have been completely processed. + * We take a clone of the original to store in + * ci.io->orig_bio to be used by end_io_acct() and + * for dec_pending to use for completion handling. + */ + struct bio *b = bio_split(bio, bio_sectors(bio) - ci.sector_count, + GFP_NOIO, &md->queue->bio_split); + ci.io->orig_bio = b; - /* - * Adjust IO stats for each split, otherwise upon queue - * reentry there will be redundant IO accounting. - * NOTE: this is a stop-gap fix, a proper fix involves - * significant refactoring of DM core's bio splitting - * (by eliminating DM's splitting and just using bio_split) - */ - part_stat_lock(); - __dm_part_stat_sub(dm_disk(md)->part0, - sectors[op_stat_group(bio_op(bio))], ci.sector_count); - part_stat_unlock(); + /* + * Adjust IO stats for each split, otherwise upon queue + * reentry there will be redundant IO accounting. + * NOTE: this is a stop-gap fix, a proper fix involves + * significant refactoring of DM core's bio splitting + * (by eliminating DM's splitting and just using bio_split) + */ + part_stat_lock(); + __dm_part_stat_sub(dm_disk(md)->part0, + sectors[op_stat_group(bio_op(bio))], ci.sector_count); + part_stat_unlock(); - bio_chain(b, bio); - trace_block_split(b, bio->bi_iter.bi_sector); - ret = submit_bio_noacct(bio); - break; - } + bio_chain(b, bio); + trace_block_split(b, bio->bi_iter.bi_sector); + ret = submit_bio_noacct(bio); } } -- dm-devel mailing list [email protected] https://listman.redhat.com/mailman/listinfo/dm-devel
