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author | Mel Gorman <mgorman@suse.de> | 2015-06-30 14:56:55 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-06-30 19:44:56 -0700 |
commit | 8a942fdea560d4ac0e9d9fabcd5201ad20e0c382 (patch) | |
tree | 452c0f5acccf96ffc54748a44ab5bc788f7dbffc /arch/ia64 | |
parent | d70ddd7a5d9aa335f9b4b0c3d879e1e70ee1e4e3 (diff) | |
download | linux-8a942fdea560d4ac0e9d9fabcd5201ad20e0c382.tar.bz2 |
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 <mgorman@suse.de>
Tested-by: Nate Zimmer <nzimmer@sgi.com>
Tested-by: Waiman Long <waiman.long@hp.com>
Tested-by: Daniel J Blueman <daniel@numascale.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Robin Holt <robinmholt@gmail.com>
Cc: Nate Zimmer <nzimmer@sgi.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Waiman Long <waiman.long@hp.com>
Cc: Scott Norton <scott.norton@hp.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/ia64')
-rw-r--r-- | arch/ia64/mm/numa.c | 19 |
1 files changed, 7 insertions, 12 deletions
diff --git a/arch/ia64/mm/numa.c b/arch/ia64/mm/numa.c index ea21d4cad540..aa19b7ac8222 100644 --- a/arch/ia64/mm/numa.c +++ b/arch/ia64/mm/numa.c @@ -58,27 +58,22 @@ paddr_to_nid(unsigned long paddr) * SPARSEMEM to allocate the SPARSEMEM sectionmap on the NUMA node where * the section resides. */ -int __meminit __early_pfn_to_nid(unsigned long pfn) +int __meminit __early_pfn_to_nid(unsigned long pfn, + struct mminit_pfnnid_cache *state) { int i, section = pfn >> PFN_SECTION_SHIFT, ssec, esec; - /* - * NOTE: The following SMP-unsafe globals are only used early in boot - * when the kernel is running single-threaded. - */ - static int __meminitdata last_ssec, last_esec; - static int __meminitdata last_nid; - if (section >= last_ssec && section < last_esec) - return last_nid; + if (section >= state->last_start && section < state->last_end) + return state->last_nid; for (i = 0; i < num_node_memblks; i++) { ssec = node_memblk[i].start_paddr >> PA_SECTION_SHIFT; esec = (node_memblk[i].start_paddr + node_memblk[i].size + ((1L << PA_SECTION_SHIFT) - 1)) >> PA_SECTION_SHIFT; if (section >= ssec && section < esec) { - last_ssec = ssec; - last_esec = esec; - last_nid = node_memblk[i].nid; + state->last_start = ssec; + state->last_end = esec; + state->last_nid = node_memblk[i].nid; return node_memblk[i].nid; } } |