Hi Mike, We've been working off-list to develop a method of getting DM events that is reliable, and also can monitor events from multiple DM devices from a single thread. In short, these enable an open file descriptor to /dev/mapper/control to be polled. If the fd indicates POLLIN, some DM device has experienced an event. Figuring out which is made easier by adding event_nr in a backwards-compatible way to DM_LIST_DEVICES, so userspace can compare against previously seen per-device event_nrs. A new ioctl is also added, to rearm the fd so it may be re-poll()ed. See individual patch commitlogs for more details. Thanks to Mikulas for redeveloping earlier versions into this patchset, as well as the other RH LVM devs who provided early internal feedback! Regards -- Andy Mikulas Patocka (3): dm: a basic support for using the select or poll function dm-ioctl: add a new DM_DEV_ARM_POLL ioctl dm-ioctl: report event number in DM_LIST_DEVICES drivers/md/dm-core.h | 3 ++ drivers/md/dm-ioctl.c | 109 +++++++++++++++++++++++++++++++++--------- drivers/md/dm.c | 5 ++ include/uapi/linux/dm-ioctl.h | 6 ++- 4 files changed, 99 insertions(+), 24 deletions(-) -- 2.9.3 -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
