On Wed, Feb 10, 2021 at 05:08:05AM +0100, Michał Mirosław wrote: > On Tue, Feb 09, 2021 at 09:30:38PM +0100, Michal Rostecki wrote: > > From: Michal Rostecki <mroste...@suse.com> > > > > Add the btrfs_check_mixed() function which checks if the filesystem has > > the mixed type of devices (non-rotational and rotational). This > > information is going to be used in roundrobin raid1 read policy.a > [...] > > @@ -669,8 +699,12 @@ static int btrfs_open_one_device(struct > > btrfs_fs_devices *fs_devices, > > } > > > > q = bdev_get_queue(bdev); > > - if (!blk_queue_nonrot(q)) > > + rotating = !blk_queue_nonrot(q); > > + device->rotating = rotating; > > + if (rotating) > > fs_devices->rotating = true; > > + if (!fs_devices->mixed) > > + fs_devices->mixed = btrfs_check_mixed(fs_devices, rotating); > [...] > > Since this is adding to a set, a faster way is: > > if (fs_devices->rotating != rotating) > fs_devices->mixed = true; >
Good idea. > The scan might be necessary on device removal, though. > And good point. I didn't address the case of device removal at all. > > - if (!blk_queue_nonrot(q)) > > + rotating = !blk_queue_nonrot(q); > > + device->rotating = rotating; > > + if (rotating) > > fs_devices->rotating = true; > > + if (!fs_devices->mixed) > > + fs_devices->mixed = btrfs_check_mixed(fs_devices, rotating); > > Duplication. Maybe pull all this into a function? > Will do that as well. > Best Regards, > Michał Mirosław Regards, Michal