• Mel Gorman's avatar
    mm: numa: Sanitize task_numa_fault() callsites · c61109e3
    Mel Gorman authored
    There are three callers of task_numa_fault():
    
     - do_huge_pmd_numa_page():
         Accounts against the current node, not the node where the
         page resides, unless we migrated, in which case it accounts
         against the node we migrated to.
    
     - do_numa_page():
         Accounts against the current node, not the node where the
         page resides, unless we migrated, in which case it accounts
         against the node we migrated to.
    
     - do_pmd_numa_page():
         Accounts not at all when the page isn't migrated, otherwise
         accounts against the node we migrated towards.
    
    This seems wrong to me; all three sites should have the same
    sementaics, furthermore we should accounts against where the page
    really is, we already know where the task is.
    
    So modify all three sites to always account; we did after all receive
    the fault; and always account to where the page is after migration,
    regardless of success.
    
    They all still differ on when they clear the PTE/PMD; ideally that
    would get sorted too.
    Signed-off-by: default avatarMel Gorman <mgorman@suse.de>
    Reviewed-by: default avatarRik van Riel <riel@redhat.com>
    Cc: Andrea Arcangeli <aarcange@redhat.com>
    Cc: Johannes Weiner <hannes@cmpxchg.org>
    Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
    Cc: <stable@kernel.org>
    Signed-off-by: default avatarPeter Zijlstra <peterz@infradead.org>
    Link: http://lkml.kernel.org/r/1381141781-10992-8-git-send-email-mgorman@suse.deSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
    c61109e3
memory.c 117 KB