History log of /include/xen/balloon.h
Revision Date Author Comments
cd9151e26d31048b2b5e00fd02e110e07d2200c9 04-Aug-2013 Stefano Stabellini <stefano.stabellini@eu.citrix.com> xen/balloon: set a mapping for ballooned out pages

Currently ballooned out pages are mapped to 0 and have INVALID_P2M_ENTRY
in the p2m. These ballooned out pages are used to map foreign grants
by gntdev and blkback (see alloc_xenballooned_pages).

Allocate a page per cpu and map all the ballooned out pages to the
corresponding mfn. Set the p2m accordingly. This way reading from a
ballooned out page won't cause a kernel crash (see
http://lists.xen.org/archives/html/xen-devel/2012-12/msg01154.html).

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
CC: alex@alex.org.uk
CC: dcrisan@flexiant.com
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
070680218379e15c1901f4bf21b98e3cbf12b527 15-Dec-2011 Kay Sievers <kay.sievers@vrfy.org> xen-balloon: convert sysdev_class to a regular subsystem

After all sysdev classes are ported to regular driver core entities, the
sysdev implementation will be entirely removed from the kernel.

Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
693394b8c3dcee1a3baa52e30fdc3323d88cd579 29-Sep-2011 Stefano Stabellini <stefano.stabellini@eu.citrix.com> xen: add an "highmem" parameter to alloc_xenballooned_pages

Add an highmem parameter to alloc_xenballooned_pages, to allow callers to
request lowmem or highmem pages.

Fix the code style of free_xenballooned_pages' prototype.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
080e2be7884322daffe75a831e879fbe7de383ab 26-Jul-2011 Daniel Kiper <dkiper@net-space.pl> xen/balloon: memory hotplug support for Xen balloon driver

Memory hotplug support for Xen balloon driver. It should be mentioned
that hotplugged memory is not onlined automatically. It should be onlined
by user through standard sysfs interface.

Memory could be hotplugged in following steps:

1) dom0: xl mem-max <domU> <maxmem>
where <maxmem> is >= requested memory size,

2) dom0: xl mem-set <domU> <memory>
where <memory> is requested memory size; alternatively memory
could be added by writing proper value to
/sys/devices/system/xen_memory/xen_memory0/target or
/sys/devices/system/xen_memory/xen_memory0/target_kb on dumU,

3) domU: for i in /sys/devices/system/memory/memory*/state; do \
[ "`cat "$i"`" = offline ] && echo online > "$i"; done

Memory could be onlined automatically on domU by adding following line to
udev rules:

SUBSYSTEM=="memory", ACTION=="add", RUN+="/bin/sh -c '[ -f /sys$devpath/state ] && echo online > /sys$devpath/state'"

In that case step 3 should be omitted.

Signed-off-by: Daniel Kiper <dkiper@net-space.pl>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
a50777c791031d7345ce95785ea6220f67339d90 08-Jul-2011 Dan Magenheimer <dan.magenheimer@oracle.com> xen: tmem: self-ballooning and frontswap-selfshrinking

This patch introduces two in-kernel drivers for Xen transcendent memory
("tmem") functionality that complement cleancache and frontswap. Both
use control theory to dynamically adjust and optimize memory utilization.
Selfballooning controls the in-kernel Xen balloon driver, targeting a goal
value (vm_committed_as), thus pushing less frequently used clean
page cache pages (through the cleancache code) into Xen tmem where
Xen can balance needs across all VMs residing on the physical machine.
Frontswap-selfshrinking controls the number of pages in frontswap,
driving it towards zero (effectively doing a partial swapoff) when
in-kernel memory pressure subsides, freeing up RAM for other VMs.

More detail is provided in the header comment of xen-selfballooning.c.

Signed-off-by: Dan Magenheimer <dan.magenheimer@oracle.com>

[v8: konrad.wilk@oracle.com: set default enablement depending on frontswap]
[v7: konrad.wilk@oracle.com: fix capitalization and punctuation in comments]
[v6: fix frontswap-selfshrinking initialization]
[v6: konrad.wilk@oracle.com: fix init pr_infos; add comments about swap]
[v5: konrad.wilk@oracle.com: add NULL to attr list; move inits up to decls]
[v4: dkiper@net-space.pl: use strict_strtoul plus a few syntactic nits]
[v3: konrad.wilk@oracle.com: fix potential divides-by-zero]
[v3: konrad.wilk@oracle.com: add many more comments, fix nits]
[v2: rebased to linux-3.0-rc1]
[v2: Ian.Campbell@citrix.com: reorganize as new file (xen-selfballoon.c)]
[v2: dkiper@net-space.pl: proper access to vm_committed_as]
[v2: dkiper@net-space.pl: accounting fixes]
Cc: Jan Beulich <JBeulich@novell.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: <xen-devel@lists.xensource.com>
b6f3067985f12d514187059fb10fe3c877f87cb2 15-Mar-2011 Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> xen-balloon: Add interface to retrieve ballooned pages

Pages that have been ballooned are useful for other Xen drivers doing
grant table actions, because these pages have valid struct page/PFNs but
have no valid MFN so are available for remapping.

Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
[v2: Deal with rebasing on top of modified balloon code]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
803eb047a28d239809fff1f87274cdaa94e0d8ea 14-Mar-2011 Daniel De Graaf <dgdegra@tycho.nsa.gov> xen-balloon: Move core balloon functionality out of module

The basic functionality of ballooning pages is useful for Xen drivers in
general. Rather than require a dependency on the balloon module, split
the functionality that is reused into the core. The balloon module is
still required to follow ballooning requests from xenstore or to view
balloon statistics in sysfs.

Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
d19c8e516e0a17e049bcfbe96f86e040254ddf14 03-Oct-2008 Jeremy Fitzhardinge <jeremy@goop.org> xen: remove unused balloon.h

The balloon driver doesn't have any externally callable functions at
the moment, so remove the (effectively empty) header. We can add it
back if we need to.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
1775826ceec51187aa868406585799b7e76ffa7d 02-Apr-2008 Jeremy Fitzhardinge <jeremy@goop.org> xen: add balloon driver

The balloon driver allows memory to be dynamically added or removed from the domain,
in order to allow host memory to be balanced between multiple domains.

This patch introduces the Xen balloon driver, though it currently only
allows a domain to be shrunk from its initial size (and re-grown back to
that size). A later patch will add the ability to grow a domain beyond
its initial size.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>