Revision - 207ee84 - target: Use system workqueue for ALUA transitions - origin: https://github.com/torvalds/linux

visit type:

https://github.com/torvalds/linux

05 April 2024, 19:05:47 UTC

Revision 207ee84133c00a8a2a5bdec94df4a5b37d78881c authored by Mike Christie on 02 March 2017, 05:13:26 UTC, committed by Nicholas Bellinger on 18 March 2017, 21:47:27 UTC

target: Use system workqueue for ALUA transitions

If tcmu-runner is processing a STPG and needs to change the kernel's
ALUA state then we cannot use the same work queue for task management
requests and ALUA transitions, because we could deadlock. The problem
occurs when a STPG times out before tcmu-runner is able to
call into target_tg_pt_gp_alua_access_state_store->
core_alua_do_port_transition -> core_alua_do_transition_tg_pt ->
queue_work. In this case, the tmr is on the work queue waiting for
the STPG to complete, but the STPG transition is now queued behind
the waiting tmr.

Note:
This bug will also be fixed by this patch:
http://www.spinics.net/lists/target-devel/msg14560.html
which switches the tmr code to use the system workqueues.

For both, I am not sure if we need a dedicated workqueue since
it is not a performance path and I do not think we need WQ_MEM_RECLAIM
to make forward progress to free up memory like the block layer does.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

1 parent 0a41457

Files
Changes

Permalinks

Tip revision: 207ee84133c00a8a2a5bdec94df4a5b37d78881c authored by Mike Christie on 02 March 2017, 05:13:26 UTC
target: Use system workqueue for ALUA transitions

Tip revision: 207ee84

File	Mode	Size
Documentation
arch
block
certs
crypto
drivers
firmware
fs
include
init
ipc
kernel
lib
mm
net
samples
scripts
security
sound
tools
usr
virt
.cocciconfig	-rw-r--r--	59 bytes
.get_maintainer.ignore	-rw-r--r--	31 bytes
.gitattributes	-rw-r--r--	30 bytes
.gitignore	-rw-r--r--	1.3 KB
.mailmap	-rw-r--r--	7.7 KB
COPYING	-rw-r--r--	18.3 KB
CREDITS	-rw-r--r--	96.0 KB
Kbuild	-rw-r--r--	2.8 KB
Kconfig	-rw-r--r--	252 bytes
MAINTAINERS	-rw-r--r--	389.3 KB
Makefile	-rw-r--r--	57.7 KB
README	-rw-r--r--	722 bytes

Showing with 0 additions and 0 deletions (0 / 0 diffs computed)

Computing file changes ...

https://github.com/torvalds/linux

target: Use system workqueue for ALUA transitions

README