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| author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2017-09-29 17:08:16 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-12-25 16:26:15 +0300 |
| commit | 4afaf6ea65acb07e151470580d89e6a2c0268610 (patch) | |
| tree | 8202afdcd967fcb26c5547c525ac8a3b2b7cc4bd /mm/page_alloc.c | |
| parent | 36295155d8d4c3f9fb425faac9120559c051b861 (diff) | |
| download | linux-4afaf6ea65acb07e151470580d89e6a2c0268610.tar.xz | |
mm/sparsemem: Allocate mem_section at runtime for CONFIG_SPARSEMEM_EXTREME=y
commit 83e3c48729d9ebb7af5a31a504f3fd6aff0348c4 upstream.
Size of the mem_section[] array depends on the size of the physical address space.
In preparation for boot-time switching between paging modes on x86-64
we need to make the allocation of mem_section[] dynamic, because otherwise
we waste a lot of RAM: with CONFIG_NODE_SHIFT=10, mem_section[] size is 32kB
for 4-level paging and 2MB for 5-level paging mode.
The patch allocates the array on the first call to sparse_memory_present_with_active_regions().
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@suse.de>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170929140821.37654-2-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'mm/page_alloc.c')
| -rw-r--r-- | mm/page_alloc.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index d51c2087c498..02cf30bd01cd 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5651,6 +5651,16 @@ void __init sparse_memory_present_with_active_regions(int nid) unsigned long start_pfn, end_pfn; int i, this_nid; +#ifdef CONFIG_SPARSEMEM_EXTREME + if (!mem_section) { + unsigned long size, align; + + size = sizeof(struct mem_section) * NR_SECTION_ROOTS; + align = 1 << (INTERNODE_CACHE_SHIFT); + mem_section = memblock_virt_alloc(size, align); + } +#endif + for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, &this_nid) memory_present(this_nid, start_pfn, end_pfn); } |