On Thu, Jul 28, 2016 at 02:22:14PM +0800, ZhengYuan Liu wrote: > The counter conf->empty_inactive_list_nr is only used for determine if the > raid5 is congested which is deal with in function raid5_congested(). > It was increased in get_free_stripe() when conf->inactive_list got to be > empty and decreased in release_inactive_stripe_list() when splice > temp_inactive_list to conf->inactive_list. However, this may have a > problem when raid5_get_active_stripe or stripe_add_to_batch_list was called, > because these two functions may call list_del_init(&sh->lru) to delete sh from > "conf->inactive_list + hash" which may cause "conf->inactive_list + hash" to > be empty when atomic_inc_not_zero(&sh->count) got false. So a check should be > done at these two point and increase empty_inactive_list_nr accordingly. > Otherwise the counter may get to be negative number which would influence > async readahead from VFS. > > Signed-off-by: ZhengYuan Liu <liuzhengyuan@xxxxxxxxxx> Applied, thanks! -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
