diff options
author | Michal Hocko <mhocko@suse.com> | 2017-07-06 15:37:45 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-07-06 16:24:32 -0700 |
commit | 1b862aecfbd419cdc4553645bf86d07554279bed (patch) | |
tree | c219675bc522f504b83ffaa522eb2ed4292961b9 /drivers | |
parent | bfe63d3beabfac93521c8b7ccd40befd7a90148e (diff) | |
download | linux-1b862aecfbd419cdc4553645bf86d07554279bed.tar.bz2 |
mm, memory_hotplug: get rid of is_zone_device_section
Device memory hotplug hooks into regular memory hotplug only half way.
It needs memory sections to track struct pages but there is no
need/desire to associate those sections with memory blocks and export
them to the userspace via sysfs because they cannot be onlined anyway.
This is currently expressed by for_device argument to arch_add_memory
which then makes sure to associate the given memory range with
ZONE_DEVICE. register_new_memory then relies on is_zone_device_section
to distinguish special memory hotplug from the regular one. While this
works now, later patches in this series want to move __add_zone outside
of arch_add_memory path so we have to come up with something else.
Add want_memblock down the __add_pages path and use it to control
whether the section->memblock association should be done.
arch_add_memory then just trivially want memblock for everything but
for_device hotplug.
remove_memory_section doesn't need is_zone_device_section either. We
can simply skip all the memblock specific cleanup if there is no
memblock for the given section.
This shouldn't introduce any functional change.
Link: http://lkml.kernel.org/r/20170515085827.16474-5-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Daniel Kiper <daniel.kiper@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Tobias Regnery <tobias.regnery@gmail.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/base/memory.c | 23 |
1 files changed, 9 insertions, 14 deletions
diff --git a/drivers/base/memory.c b/drivers/base/memory.c index 90225ffee501..f8fd562c3f18 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -685,14 +685,6 @@ static int add_memory_block(int base_section_nr) return 0; } -static bool is_zone_device_section(struct mem_section *ms) -{ - struct page *page; - - page = sparse_decode_mem_map(ms->section_mem_map, __section_nr(ms)); - return is_zone_device_page(page); -} - /* * need an interface for the VM to add new memory regions, * but without onlining it. @@ -702,9 +694,6 @@ int register_new_memory(int nid, struct mem_section *section) int ret = 0; struct memory_block *mem; - if (is_zone_device_section(section)) - return 0; - mutex_lock(&mem_sysfs_mutex); mem = find_memory_block(section); @@ -741,11 +730,16 @@ static int remove_memory_section(unsigned long node_id, { struct memory_block *mem; - if (is_zone_device_section(section)) - return 0; - mutex_lock(&mem_sysfs_mutex); + + /* + * Some users of the memory hotplug do not want/need memblock to + * track all sections. Skip over those. + */ mem = find_memory_block(section); + if (!mem) + goto out_unlock; + unregister_mem_sect_under_nodes(mem, __section_nr(section)); mem->section_count--; @@ -754,6 +748,7 @@ static int remove_memory_section(unsigned long node_id, else put_device(&mem->dev); +out_unlock: mutex_unlock(&mem_sysfs_mutex); return 0; } |