linux-stable.git/mm/memory_hotplug.c, branch v6.6.2

mm/memory_hotplug: embed vmem_altmap details in memory block

2023-08-21T20:37:49+00:00

With memmap on memory, some architecture needs more details w.r.t altmap
such as base_pfn, end_pfn, etc to unmap vmemmap memory.  Instead of
computing them again when we remove a memory block, embed vmem_altmap
details in struct memory_block if we are using memmap on memory block
feature.

[yangyingliang@huawei.com: fix error return code in add_memory_resource()]
  Link: https://lkml.kernel.org/r/20230809081552.1351184-1-yangyingliang@huawei.com
Link: https://lkml.kernel.org/r/20230808091501.287660-7-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V 
Signed-off-by: Yang Yingliang 
Acked-by: Michal Hocko 
Acked-by: David Hildenbrand 
Cc: Christophe Leroy 
Cc: Michael Ellerman 
Cc: Nicholas Piggin 
Cc: Oscar Salvador 
Cc: Vishal Verma 
Signed-off-by: Andrew Morton

mm/memory_hotplug: support memmap_on_memory when memmap is not aligned to pageblocks

2023-08-21T20:37:49+00:00

Currently, memmap_on_memory feature is only supported with memory block
sizes that result in vmemmap pages covering full page blocks.  This is
because memory onlining/offlining code requires applicable ranges to be
pageblock-aligned, for example, to set the migratetypes properly.

This patch helps to lift that restriction by reserving more pages than
required for vmemmap space.  This helps the start address to be page block
aligned with different memory block sizes.  Using this facility implies
the kernel will be reserving some pages for every memoryblock.  This
allows the memmap on memory feature to be widely useful with different
memory block size values.

For ex: with 64K page size and 256MiB memory block size, we require 4
pages to map vmemmap pages, To align things correctly we end up adding a
reserve of 28 pages.  ie, for every 4096 pages 28 pages get reserved.

Link: https://lkml.kernel.org/r/20230808091501.287660-5-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V 
Acked-by: Michal Hocko 
Acked-by: David Hildenbrand 
Cc: Christophe Leroy 
Cc: Michael Ellerman 
Cc: Nicholas Piggin 
Cc: Oscar Salvador 
Cc: Vishal Verma 
Signed-off-by: Andrew Morton

mm/memory_hotplug: allow architecture to override memmap on memory support check

2023-08-21T20:37:48+00:00

Some architectures would want different restrictions. Hence add an
architecture-specific override.

The PMD_SIZE check is moved there.

Link: https://lkml.kernel.org/r/20230808091501.287660-4-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V 
Acked-by: Michal Hocko 
Acked-by: David Hildenbrand 
Cc: Christophe Leroy 
Cc: Michael Ellerman 
Cc: Nicholas Piggin 
Cc: Oscar Salvador 
Cc: Vishal Verma 
Signed-off-by: Andrew Morton

mm/memory_hotplug: allow memmap on memory hotplug request to fallback

2023-08-21T20:37:48+00:00

If not supported, fallback to not using memap on memmory. This avoids
the need for callers to do the fallback.

Link: https://lkml.kernel.org/r/20230808091501.287660-3-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V 
Acked-by: Michal Hocko 
Acked-by: David Hildenbrand 
Cc: Christophe Leroy 
Cc: Michael Ellerman 
Cc: Nicholas Piggin 
Cc: Oscar Salvador 
Cc: Vishal Verma 
Signed-off-by: Andrew Morton

mm/memory_hotplug: document the signal_pending() check in offline_pages()

2023-08-18T17:12:19+00:00

Let's update the documentation that any signal is sufficient, and add a
comment that not only checking for fatal signals is historical baggage:
changing it now could break existing user space.  although unlikely.

For example, when an app provides a custom SIGALRM handler and triggers
memory offlining, the timeout cmd would no longer stop memory offlining,
because SIGALRM would no longer be considered a fatal signal.

Note that using signal_pending() instead of fatal_signal_pending() is
an anti-pattern, but slowly deprecating that behavior to eventually
change it in the far future is probably not worth the effort.  If this
ever becomes relevant for user-space, we might want to rethink.

Link: https://lkml.kernel.org/r/20230711174050.603820-1-david@redhat.com
Signed-off-by: David Hildenbrand 
Acked-by: Michal Hocko 
Cc: Oscar Salvador 
Cc: Jonathan Corbet 
Signed-off-by: Andrew Morton

mm: remove unnecessary pagevec includes

2023-06-23T23:59:31+00:00

These files no longer need pagevec.h, mostly due to function declarations
being moved out of it.

Link: https://lkml.kernel.org/r/20230621164557.3510324-14-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) 
Signed-off-by: Andrew Morton

mm/mm_init.c: remove reset_node_present_pages()

2023-06-19T23:19:05+00:00

reset_node_present_pages() only get called in hotadd_init_pgdat(), move
the action that clear present pages to free_area_init_core_hotplug(), so
the helper can be removed.

Link: https://lkml.kernel.org/r/20230607025056.1348-1-haifeng.xu@shopee.com
Signed-off-by: Haifeng Xu 
Suggested-by: David Hildenbrand 
Cc: Michal Hocko 
Cc: Mike Rapoport (IBM) 
Cc: Oscar Salvador 
Signed-off-by: Andrew Morton

mm/memory_hotplug: remove reset_node_managed_pages() in hotadd_init_pgdat()

2023-06-19T23:19:05+00:00

managed pages has already been set to 0 in free_area_init_core_hotplug(),
via zone_init_internals() on each zone.  It's pointless to reset again.

Furthermore, reset_node_managed_pages() no longer needs to be exposed
outside of mm/memblock.c.  Remove declaration in include/linux/memblock.h
and define it as static.

In addtion to this, the only caller of reset_node_managed_pages() is
reset_all_zones_managed_pages(), which is annotated with __init, so it
should be safe to also mark reset_node_managed_pages() as __init.

Link: https://lkml.kernel.org/r/20230607024548.1240-1-haifeng.xu@shopee.com
Signed-off-by: Haifeng Xu 
Suggested-by: David Hildenbrand 
Cc: Michal Hocko 
Cc: Mike Rapoport (IBM) 
Cc: Oscar Salvador 
Signed-off-by: Andrew Morton

mm/sparse: remove unused parameters in sparse_remove_section()

2023-06-19T23:19:04+00:00

These parameters ms and map_offset are not used in
sparse_remove_section(), so remove them.

The __remove_section() is only called by __remove_pages(), remove it.  And
put the WARN_ON_ONCE() in sparse_remove_section().

Link: https://lkml.kernel.org/r/20230607023952.2247489-1-yajun.deng@linux.dev
Signed-off-by: Yajun Deng 
Reviewed-by: David Hildenbrand 
Cc: Oscar Salvador 
Signed-off-by: Andrew Morton

mm: memory_hotplug: fix format string in warnings

2023-06-09T23:25:18+00:00

The format string in __add_pages and __remove_pages has a typo and prints
e.g., "Misaligned __add_pages start: 0xfc605 end: #fc609" instead of
"Misaligned __add_pages start: 0xfc605 end: 0xfc609" Fix "#%lx" => "%#lx"

Link: https://lkml.kernel.org/r/20230510090758.3537242-1-rick.wertenbroek@gmail.com
Signed-off-by: Rick Wertenbroek 
Reviewed-by: David Hildenbrand 
Reviewed-by: Mike Rapoport (IBM) 
Cc: Oscar Salvador 
Signed-off-by: Andrew Morton