lkml.org 
[lkml]   [2021]   [Jul]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH v6 2/6] mm/memplicy: add page allocation function for MPOL_PREFERRED_MANY policy
    Date
    The semantics of MPOL_PREFERRED_MANY is similar to MPOL_PREFERRED,
    that it will first try to allocate memory from the preferred node(s),
    and fallback to all nodes in system when first try fails.

    Add a dedicated function for it just like 'interleave' policy.

    Link: https://lore.kernel.org/r/20200630212517.308045-9-ben.widawsky@intel.com
    Suggested-by: Michal Hocko <mhocko@suse.com>
    Co-developed-by: Ben Widawsky <ben.widawsky@intel.com>
    Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
    Signed-off-by: Feng Tang <feng.tang@intel.com>
    ---
    mm/mempolicy.c | 19 +++++++++++++++++++
    1 file changed, 19 insertions(+)

    diff --git a/mm/mempolicy.c b/mm/mempolicy.c
    index 17b5800b7dcc..d17bf018efcc 100644
    --- a/mm/mempolicy.c
    +++ b/mm/mempolicy.c
    @@ -2153,6 +2153,25 @@ static struct page *alloc_page_interleave(gfp_t gfp, unsigned order,
    return page;
    }

    +static struct page *alloc_page_preferred_many(gfp_t gfp, unsigned int order,
    + struct mempolicy *pol)
    +{
    + struct page *page;
    +
    + /*
    + * This is a two pass approach. The first pass will only try the
    + * preferred nodes but skip the direct reclaim and allow the
    + * allocation to fail, while the second pass will try all the
    + * nodes in system.
    + */
    + page = __alloc_pages(((gfp | __GFP_NOWARN) & ~__GFP_DIRECT_RECLAIM),
    + order, first_node(pol->nodes), &pol->nodes);
    + if (!page)
    + page = __alloc_pages(gfp, order, numa_node_id(), NULL);
    +
    + return page;
    +}
    +
    /**
    * alloc_pages_vma - Allocate a page for a VMA.
    * @gfp: GFP flags.
    --
    2.7.4
    \
     
     \ /
      Last update: 2021-07-12 11:10    [W:4.058 / U:0.052 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site