01 May, 2013

1 commit

  • Allow Xen tmem shim to be built/loaded as a module. Xen self-ballooning
    and frontswap-selfshrinking are now also "lazily" initialized when the
    Xen tmem shim is loaded as a module, unless explicitly disabled by
    module parameters.

    Note runtime dependency disallows loading if cleancache/frontswap lazy
    initialization patches are not present.

    If built-in (not built as a module), the original mechanism of enabling
    via a kernel boot parameter is retained, but this should be considered
    deprecated.

    Note that module unload is explicitly not yet supported.

    [v1: Removed the [CLEANCACHE|FRONTSWAP]_HAS_LAZY_INIT ifdef]
    [v2: Squashed the xen/tmem: Remove the subsys call patch in]
    [akpm@linux-foundation.org: fix build (disable_frontswap_selfshrinking undeclared)]
    Signed-off-by: Dan Magenheimer
    Signed-off-by: Konrad Rzeszutek Wilk
    Signed-off-by: Bob Liu
    Cc: Wanpeng Li
    Cc: Andor Daam
    Cc: Florian Schmaus
    Cc: Minchan Kim
    Cc: Stefan Hengelein
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Dan Magenheimer
     

21 Mar, 2012

1 commit

  • Use 'bool' for boolean variables. Do proper section placement.
    Eliminate an unnecessary export.

    Signed-off-by: Jan Beulich
    Acked-by: Dan Magenheimer
    Signed-off-by: Konrad Rzeszutek Wilk

    Jan Beulich
     

09 Jul, 2011

1 commit

  • 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

    [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
    Cc: Jeremy Fitzhardinge
    Cc:

    Dan Magenheimer