linux/drivers/xen/xenbus
SeongJae Park 8a105678fb xenbus/backend: Add memory pressure handler callback
Granting pages consumes backend system memory.  In systems configured
with insufficient spare memory for those pages, it can cause a memory
pressure situation.  However, finding the optimal amount of the spare
memory is challenging for large systems having dynamic resource
utilization patterns.  Also, such a static configuration might lack
flexibility.

To mitigate such problems, this commit adds a memory reclaim callback to
'xenbus_driver'.  If a memory pressure is detected, 'xenbus' requests
every backend driver to volunarily release its memory.

Note that it would be able to improve the callback facility for more
sophisticated handlings of general pressures.  For example, it would be
possible to monitor the memory consumption of each device and issue the
release requests to only devices which causing the pressure.  Also, the
callback could be extended to handle not only memory, but general
resources.  Nevertheless, this version of the implementation defers such
sophisticated goals as a future work.

Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: SeongJae Park <sjpark@amazon.de>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-01-29 07:35:49 -06:00
..
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
xenbus_client.c xen: drop writing error messages to xenstore 2018-10-26 09:17:16 +02:00
xenbus_comms.c xenbus: track caller request id 2018-02-17 09:40:33 +01:00
xenbus_dev_backend.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
xenbus_dev_frontend.c xen/xenbus: fix self-deadlock after killing user process 2019-10-02 16:40:11 -04:00
xenbus_probe_backend.c xenbus/backend: Add memory pressure handler callback 2020-01-29 07:35:49 -06:00
xenbus_probe_frontend.c xenbus: move xenbus_dev_shutdown() into frontend code... 2019-12-20 13:44:35 +01:00
xenbus_probe.c xenbus: limit when state is forced to closed 2019-12-20 13:44:38 +01:00
xenbus_xs.c xenbus: Avoid deadlock during suspend due to open transactions 2019-05-28 17:32:15 -04:00
xenbus.h xenbus: move xenbus_dev_shutdown() into frontend code... 2019-12-20 13:44:35 +01:00