[dm-devel] [PATCH 0/2] multipath: Stop extra scans on stacked devices

[Benjamin Marzinski]

Whenever there is a DM_DEVICE_RESUME ioctl, a uevent is generated. Right now,
when multipath is reloading existing devices do to paths going or coming,
lvmetad will rescan those devices. This is unnecessary, and can cause a lot
of overhead. Also, multipath devices with no working paths will get scanned.
These patches make multipath set a new flag, DM_SUBSYSTEM_UDEV_FLAG0, when it
is reloading devices due to path changes, and lvmetad can safely ignore it.
They also add a new udev rules file, 11-dm-mpath.rules, to disable scanning
when it would not be useful.

Benjamin Marzinski (2):
  New udev rules to deal with stacked devices
  Mark reloads with udev flag

 Makefile.inc                |  1 +
 kpartx/devmapper.c          |  4 ++--
 kpartx/devmapper.h          |  8 +++++++-
 kpartx/kpartx.c             |  8 ++++----
 libmultipath/configure.c    |  4 ++--
 libmultipath/devmapper.c    | 26 ++++++++++++++------------
 libmultipath/devmapper.h    | 10 ++++++++--
 multipath/11-dm-mpath.rules | 34 ++++++++++++++++++++++++++++++++++
 multipath/Makefile          |  3 +++
 multipathd/cli_handlers.c   |  4 ++--
 10 files changed, 77 insertions(+), 25 deletions(-)
 create mode 100644 multipath/11-dm-mpath.rules

-- 
1.8.4.2