• Tang Chen's avatar
    memblock, mem_hotplug: make memblock skip hotpluggable regions if needed · 55ac590c
    Tang Chen authored
    
    
    Linux kernel cannot migrate pages used by the kernel.  As a result,
    hotpluggable memory used by the kernel won't be able to be hot-removed.
    To solve this problem, the basic idea is to prevent memblock from
    allocating hotpluggable memory for the kernel at early time, and arrange
    all hotpluggable memory in ACPI SRAT(System Resource Affinity Table) as
    ZONE_MOVABLE when initializing zones.
    
    In the previous patches, we have marked hotpluggable memory regions with
    MEMBLOCK_HOTPLUG flag in memblock.memory.
    
    In this patch, we make memblock skip these hotpluggable memory regions
    in the default top-down allocation function if movable_node boot option
    is specified.
    
    [akpm@linux-foundation.org: coding-style fixes]
    Signed-off-by: default avatarTang Chen <tangchen@cn.fujitsu.com>
    Signed-off-by: default avatarZhang Yanfei <zhangyanfei@cn.fujitsu.com>
    Cc: "H. Peter Anvin" <hpa@zytor.com>
    Cc: "Rafael J . Wysocki" <rjw@sisk.pl>
    Cc: Chen Tang <imtangchen@gmail.com>
    Cc: Gong Chen <gong.chen@linux.intel.com>
    Cc: Ingo Molnar <mingo@elte.hu>
    Cc: Jiang Liu <jiang.liu@huawei.com>
    Cc: Johannes Weiner <hannes@cmpxchg.org>
    Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
    Cc: Larry Woodman <lwoodman@redhat.com>
    Cc: Len Brown <lenb@kernel.org>
    Cc: Liu Jiang <jiang.liu@huawei.com>
    Cc: Mel Gorman <mgorman@suse.de>
    Cc: Michal Nazarewicz <mina86@mina86.com>
    Cc: Minchan Kim <minchan@kernel.org>
    Cc: Prarit Bhargava <prarit@redhat.com>
    Cc: Rik van Riel <riel@redhat.com>
    Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
    Cc: Tejun Heo <tj@kernel.org>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: Thomas Renninger <trenn@suse.de>
    Cc: Toshi Kani <toshi.kani@hp.com>
    Cc: Vasilis Liaskovitis <vasilis.liaskovitis@profitbricks.com>
    Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
    Cc: Wen Congyang <wency@cn.fujitsu.com>
    Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
    Cc: Yinghai Lu <yinghai@kernel.org>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    55ac590c