From 8a942fdea560d4ac0e9d9fabcd5201ad20e0c382 Mon Sep 17 00:00:00 2001 From: Mel Gorman Date: Tue, 30 Jun 2015 14:56:55 -0700 Subject: mm: meminit: make __early_pfn_to_nid SMP-safe and introduce meminit_pfn_in_nid __early_pfn_to_nid() use static variables to cache recent lookups as memblock lookups are very expensive but it assumes that memory initialisation is single-threaded. Parallel initialisation of struct pages will break that assumption so this patch makes __early_pfn_to_nid() SMP-safe by requiring the caller to cache recent search information. early_pfn_to_nid() keeps the same interface but is only safe to use early in boot due to the use of a global static variable. meminit_pfn_in_nid() is an SMP-safe version that callers must maintain their own state for. Signed-off-by: Mel Gorman Tested-by: Nate Zimmer Tested-by: Waiman Long Tested-by: Daniel J Blueman Acked-by: Pekka Enberg Cc: Robin Holt Cc: Nate Zimmer Cc: Dave Hansen Cc: Waiman Long Cc: Scott Norton Cc: "Luck, Tony" Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/mm.h | 6 ++++-- include/linux/mmzone.h | 16 +++++++++++++++- 2 files changed, 19 insertions(+), 3 deletions(-) (limited to 'include/linux') diff --git a/include/linux/mm.h b/include/linux/mm.h index d662af2d0d01..2e872f92dbac 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1726,7 +1726,8 @@ extern void sparse_memory_present_with_active_regions(int nid); #if !defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP) && \ !defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) -static inline int __early_pfn_to_nid(unsigned long pfn) +static inline int __early_pfn_to_nid(unsigned long pfn, + struct mminit_pfnnid_cache *state) { return 0; } @@ -1734,7 +1735,8 @@ static inline int __early_pfn_to_nid(unsigned long pfn) /* please see mm/page_alloc.c */ extern int __meminit early_pfn_to_nid(unsigned long pfn); /* there is a per-arch backend function. */ -extern int __meminit __early_pfn_to_nid(unsigned long pfn); +extern int __meminit __early_pfn_to_nid(unsigned long pfn, + struct mminit_pfnnid_cache *state); #endif extern void set_dma_reserve(unsigned long new_dma_reserve); diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 54d74f6eb233..b2473d822549 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -1216,10 +1216,24 @@ void sparse_init(void); #define sparse_index_init(_sec, _nid) do {} while (0) #endif /* CONFIG_SPARSEMEM */ +/* + * During memory init memblocks map pfns to nids. The search is expensive and + * this caches recent lookups. The implementation of __early_pfn_to_nid + * may treat start/end as pfns or sections. + */ +struct mminit_pfnnid_cache { + unsigned long last_start; + unsigned long last_end; + int last_nid; +}; + #ifdef CONFIG_NODES_SPAN_OTHER_NODES bool early_pfn_in_nid(unsigned long pfn, int nid); +bool meminit_pfn_in_nid(unsigned long pfn, int node, + struct mminit_pfnnid_cache *state); #else -#define early_pfn_in_nid(pfn, nid) (1) +#define early_pfn_in_nid(pfn, nid) (1) +#define meminit_pfn_in_nid(pfn, nid, state) (1) #endif #ifndef early_pfn_valid -- cgit v1.2.3