x86-32, numa: Remove redundant top-down alloc code from remap initialization

memblock_find_in_range() now does top-down allocation by default, so
there's no reason for its callers to explicitly implement it by
gradually lowering the start address.

Remove redundant top-down allocation logic from init_meminit() and
calculate_numa_remap_pages().

Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1301955840-7246-4-git-send-email-tj@kernel.org
Acked-by: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

1 files changed, 14 insertions, 29 deletions

diff --git a/arch/x86/mm/numa_32.c b/arch/x86/mm/numa_32.c
index 50e82507eab4..60701a5e0de0 100644
--- a/arch/x86/mm/numa_32.c
+++ b/arch/x86/mm/numa_32.c
@@ -270,8 +270,7 @@ static __init unsigned long calculate_numa_remap_pages(void)
         unsigned long size, reserve_pages = 0;
 
         for_each_online_node(nid) {
-                u64 node_kva_target;
-                u64 node_kva_final;
+                u64 node_kva;
 
                 /*
                  * The acpi/srat node info can show hot-add memroy zones
@@ -295,19 +294,11 @@ static __init unsigned long calculate_numa_remap_pages(void)
                 /* now the roundup is correct, convert to PAGE_SIZE pages */
                 size = size * PTRS_PER_PTE;
 
-                node_kva_target = round_down(node_end_pfn[nid] - size,
-                                                 PTRS_PER_PTE);
-                node_kva_target <<= PAGE_SHIFT;
-                do {
-                        node_kva_final = memblock_find_in_range(node_kva_target,
+                node_kva = memblock_find_in_range(node_start_pfn[nid] << PAGE_SHIFT,
                                         ((u64)node_end_pfn[nid])<<PAGE_SHIFT,
-                                                ((u64)size)<<PAGE_SHIFT,
-                                                LARGE_PAGE_BYTES);
-                        node_kva_target -= LARGE_PAGE_BYTES;
-                } while (node_kva_final == MEMBLOCK_ERROR &&
-                         (node_kva_target>>PAGE_SHIFT) > (node_start_pfn[nid]));
-
-                if (node_kva_final == MEMBLOCK_ERROR)
+                                        ((u64)size)<<PAGE_SHIFT,
+                                        LARGE_PAGE_BYTES);
+                if (node_kva == MEMBLOCK_ERROR)
                         panic("Can not get kva ram\n");
 
                 node_remap_size[nid] = size;
@@ -315,7 +306,7 @@ static __init unsigned long calculate_numa_remap_pages(void)
                 reserve_pages += size;
                 printk(KERN_DEBUG "Reserving %ld pages of KVA for lmem_map of"
                                   " node %d at %llx\n",
-                                size, nid, node_kva_final>>PAGE_SHIFT);
+                                size, nid, node_kva >> PAGE_SHIFT);
 
                 /*
                  *  prevent kva address below max_low_pfn want it on system
@@ -328,11 +319,11 @@ static __init unsigned long calculate_numa_remap_pages(void)
                  *  to use it as free.
                  *  So memblock_x86_reserve_range here, hope we don't run out of that array
                  */
-                memblock_x86_reserve_range(node_kva_final,
-                              node_kva_final+(((u64)size)<<PAGE_SHIFT),
-                              "KVA RAM");
+                memblock_x86_reserve_range(node_kva,
+                                           node_kva + (((u64)size)<<PAGE_SHIFT),
+                                           "KVA RAM");
 
-                node_remap_start_pfn[nid] = node_kva_final>>PAGE_SHIFT;
+                node_remap_start_pfn[nid] = node_kva >> PAGE_SHIFT;
         }
         printk(KERN_INFO "Reserving total of %lx pages for numa KVA remap\n",
                         reserve_pages);
@@ -356,7 +347,6 @@ static void init_remap_allocator(int nid)
 void __init initmem_init(void)
 {
         int nid;
-        long kva_target_pfn;
 
         /*
          * When mapping a NUMA machine we allocate the node_mem_map arrays
@@ -371,15 +361,10 @@ void __init initmem_init(void)
 
         kva_pages = roundup(calculate_numa_remap_pages(), PTRS_PER_PTE);
 
-        kva_target_pfn = round_down(max_low_pfn - kva_pages, PTRS_PER_PTE);
-        do {
-                kva_start_pfn = memblock_find_in_range(kva_target_pfn<<PAGE_SHIFT,
-                                        max_low_pfn<<PAGE_SHIFT,
-                                        kva_pages<<PAGE_SHIFT,
-                                        PTRS_PER_PTE<<PAGE_SHIFT) >> PAGE_SHIFT;
-                kva_target_pfn -= PTRS_PER_PTE;
-        } while (kva_start_pfn == MEMBLOCK_ERROR && kva_target_pfn > min_low_pfn);
-
+        kva_start_pfn = memblock_find_in_range(min_low_pfn << PAGE_SHIFT,
+                                max_low_pfn << PAGE_SHIFT,
+                                kva_pages << PAGE_SHIFT,
+                                PTRS_PER_PTE << PAGE_SHIFT) >> PAGE_SHIFT;
         if (kva_start_pfn == MEMBLOCK_ERROR)
                 panic("Can not get kva space\n");