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| author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2017-09-29 17:08:16 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-10-20 13:07:09 +0200 |
| commit | 83e3c48729d9ebb7af5a31a504f3fd6aff0348c4 (patch) | |
| tree | 9e42ac40f3bb837359325e0b247ec8e16c1c0b52 /mm | |
| parent | 967535223f9a8d95c187a8728480b569164cd4f4 (diff) | |
| download | linux-83e3c48729d9ebb7af5a31a504f3fd6aff0348c4.tar.gz | |
mm/sparsemem: Allocate mem_section at runtime for CONFIG_SPARSEMEM_EXTREME=y
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>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/page_alloc.c | 10 | ||||
| -rw-r--r-- | mm/sparse.c | 17 |
2 files changed, 21 insertions, 6 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 77e4d3c5c57b..8dfd13f724d9 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5646,6 +5646,16 @@ 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); } diff --git a/mm/sparse.c b/mm/sparse.c index 83b3bf6461af..b00a97398795 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -22,8 +22,7 @@ * 1) mem_section - memory sections, mem_map's for valid memory */ #ifdef CONFIG_SPARSEMEM_EXTREME -struct mem_section *mem_section[NR_SECTION_ROOTS] - ____cacheline_internodealigned_in_smp; +struct mem_section **mem_section; #else struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT] ____cacheline_internodealigned_in_smp; @@ -100,7 +99,7 @@ static inline int sparse_index_init(unsigned long section_nr, int nid) int __section_nr(struct mem_section* ms) { unsigned long root_nr; - struct mem_section* root; + struct mem_section *root = NULL; for (root_nr = 0; root_nr < NR_SECTION_ROOTS; root_nr++) { root = __nr_to_section(root_nr * SECTIONS_PER_ROOT); @@ -111,7 +110,7 @@ int __section_nr(struct mem_section* ms) break; } - VM_BUG_ON(root_nr == NR_SECTION_ROOTS); + VM_BUG_ON(!root); return (root_nr * SECTIONS_PER_ROOT) + (ms - root); } @@ -329,11 +328,17 @@ again: static void __init check_usemap_section_nr(int nid, unsigned long *usemap) { unsigned long usemap_snr, pgdat_snr; - static unsigned long old_usemap_snr = NR_MEM_SECTIONS; - static unsigned long old_pgdat_snr = NR_MEM_SECTIONS; + static unsigned long old_usemap_snr; + static unsigned long old_pgdat_snr; struct pglist_data *pgdat = NODE_DATA(nid); int usemap_nid; + /* First call */ + if (!old_usemap_snr) { + old_usemap_snr = NR_MEM_SECTIONS; + old_pgdat_snr = NR_MEM_SECTIONS; + } + usemap_snr = pfn_to_section_nr(__pa(usemap) >> PAGE_SHIFT); pgdat_snr = pfn_to_section_nr(__pa(pgdat) >> PAGE_SHIFT); if (usemap_snr == pgdat_snr) |