devlink: Change devlink health locking mechanism
authorMoshe Shemesh <moshe@mellanox.com>
Mon, 29 Apr 2019 09:41:45 +0000 (12:41 +0300)
committerDavid S. Miller <davem@davemloft.net>
Wed, 1 May 2019 15:07:03 +0000 (11:07 -0400)
commitb587bdaf5f820cf7dac2c1b351db97bf98e1f427
tree506edca56c4af13657e8f1136b5de7e9c4784960
parent5be90f993880052d95bbf6ccdca3fa081eb9b1ff
devlink: Change devlink health locking mechanism

The devlink health reporters create/destroy and user commands currently
use the devlink->lock as a locking mechanism. Different reporters have
different rules in the driver and are being created/destroyed during
different stages of driver load/unload/running. So during execution of a
reporter recover the flow can go through another reporter's destroy and
create. Such flow leads to deadlock trying to lock a mutex already
held.

With the new locking mechanism the different reporters share mutex lock
only to protect access to shared reporters list.
Added refcount per reporter, to protect the reporters from destroy while
being used.

Signed-off-by: Moshe Shemesh <moshe@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
include/net/devlink.h
net/core/devlink.c