Tim Chase 3937ab20f3 Allow for lock-free reading zfsdev_state_list. ... Restructure the zfsdev_state_list to allow for lock-free reading by converting to a simple singly-linked list from which items are never deleted and over which only forward iterations are performed. It depends on, among other things, the atomicity of accessing the zs_minor integer and zs_next pointer. This fixes a lock inversion in which the zfsdev_state_lock is used by both the sync task (txg_sync) and indirectly by any user program which uses /dev/zfs; the zfsdev_release method uses the same lock and then blocks on the sync task. The most typical failure scenerio occurs when the sync task is cleaning up a user hold while various concurrent "zfs" commands are in progress. Neither Illumos nor Solaris are affected by this issue because they use DDI interface which provides lock-free reading of device state via the ddi_get_soft_state() function. Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Closes #2301		2014-05-19 11:45:11 -07:00
..
avl	Add module versioning	2013-12-06 09:34:41 -08:00
nvpair	Fix nvlist 'Bus Error' for Sparc	2014-01-09 15:50:15 -08:00
unicode	cstyle: Resolve C style issues	2013-12-18 16:46:35 -08:00
zcommon	Check the dataset type more rigorously when fetching properties.	2014-05-06 10:41:46 -07:00
zfs	Allow for lock-free reading zfsdev_state_list.	2014-05-19 11:45:11 -07:00
zpios	cstyle: Resolve C style issues	2013-12-18 16:46:35 -08:00
.gitignore	gitignore: anchor entries at their respective directory	2013-04-02 10:50:17 -07:00
Makefile.in	Add KMODDIR to install target	2013-03-06 15:46:40 -08:00