From mboxrd@z Thu Jan 1 00:00:00 1970 From: NeilBrown Subject: Re: [PATCH v2 11/12] raid5-ppl: support disk add/remove with distributed PPL Date: Wed, 07 Dec 2016 12:29:52 +1100 Message-ID: <87wpfc34rz.fsf@notabene.neil.brown.name> References: <20161205153113.7268-1-artur.paszkiewicz@intel.com> <20161205153113.7268-12-artur.paszkiewicz@intel.com> Mime-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha256; protocol="application/pgp-signature" Return-path: In-Reply-To: <20161205153113.7268-12-artur.paszkiewicz@intel.com> Sender: linux-raid-owner@vger.kernel.org To: Artur Paszkiewicz , shli@kernel.org Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids --=-=-= Content-Type: text/plain On Tue, Dec 06 2016, Artur Paszkiewicz wrote: > Add a function to modify the log by adding or removing an rdev when a > drive fails or is added as a spare. > > Adding a drive to the log is as simple as initializing and adding a new > child log, removing a drive is more complicated because it requires > stopping the child log and freeing all of its resources. In order to do > that, we busy wait for any submitted log bios to complete and then > manually finish and free the io_units. No new log requests will happen > at this point. A new list is added to struct r5l_io_unit to have access > to stripes that have been written to the log but are not completely > processed yet. Busy-wait for IO to finish? Seriously? At the very very least you need to cond_resched() in there, but an actual wait would be much better. NeilBrown --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEG8Yp69OQ2HB7X0l6Oeye3VZigbkFAlhHZhAACgkQOeye3VZi gbnXog/9FoTh7rj6m0qmzksbi2tq6A3zzEe6X+Pkka/uNoqvnB1D5PMgOW4CJ1i1 2S+eufABsH3O53FOsnFFQiDQ2/ZmdWs6FDDSJy6kZFSJ37AFIVezDJjXOgNwF77T /qi4P8THshYSKoig84uHAVsPyD0l0JCelaIEfLmgC5kBwdhxO3jU55hBEtuMCzZs SqgZhM+MhfPxensXg2vauCLTWyRJNzJ+Nav1EjuEV+ZvuVY9S7agDGBN+1ma1a5G K3WJFzcg61pd2xULMkFWdNcA2cWYyXpkQFnKdy+vXY7fxJL7mRiVS5tEkXApzh2+ UeuhnIqATA+BgWnTvFC8nYvwkeOmSIhZcW+Ud9e6T/Yyk0jwKbLRi0u0bWyvhOcQ kTV1vmH/Rd8scGu2mjEylm8dZKqDZwOBRgTCiXJRz3cbEB4KEXOQSvCCHp5yGKH4 7D2gOGdoVgdDQ7lGkANCLODBnpO7f1bwrVyn2Gj9DTmxoWo3za4sxA0RFL0/QeeT iDC7HeqXA6LzEayXGijqVNKypz2KLCfy6p7G0FDqVWXEh1glbkppsWxFDi8ecbgT zicWGmyeulFWZjz77NMwGNP3TD7NRStMTO1cTA5DaBpgxZ/QLyYWjJ5M6TPf2VZ+ 4DD2o5VAd5Lsx7p1B37x2o4Nb9m2C7ah0/qA+kKbO+41TL0LdEs= =4dpa -----END PGP SIGNATURE----- --=-=-=--