memblock: split memblock_find_base() out of __memblock_alloc_base()

This will be used by the array resize code and might prove useful
to some arch code as well at which point it can be made non-static.

Also add comment as to why aligning size is important

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---

v2. Fix loss of size alignment
v3. Fix result code

diff --git a/mm/memblock.c b/mm/memblock.c
index ae856d4e25a37ea71fdc658a667b897508f865e4..b775fca4fba54d4fa9ce68528cb942da32607d60 100644 (file)
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -345,12 +345,15 @@ phys_addr_t __init memblock_alloc_nid(phys_addr_t size, phys_addr_t align, int n
 
        BUG_ON(0 == size);
 
+       /* We align the size to limit fragmentation. Without this, a lot of
+        * small allocs quickly eat up the whole reserve array on sparc
+        */
+       size = memblock_align_up(size, align);
+
        /* We do a bottom-up search for a region with the right
         * nid since that's easier considering how memblock_nid_range()
         * works
         */
-       size = memblock_align_up(size, align);
-
        for (i = 0; i < mem->cnt; i++) {
                phys_addr_t ret = memblock_alloc_nid_region(&mem->regions[i],
                                               size, align, nid);
@@ -366,20 +369,7 @@ phys_addr_t __init memblock_alloc(phys_addr_t size, phys_addr_t align)
        return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
 }
 
-phys_addr_t __init memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
-{
-       phys_addr_t alloc;
-
-       alloc = __memblock_alloc_base(size, align, max_addr);
-
-       if (alloc == 0)
-               panic("ERROR: Failed to allocate 0x%llx bytes below 0x%llx.\n",
-                     (unsigned long long) size, (unsigned long long) max_addr);
-
-       return alloc;
-}
-
-phys_addr_t __init __memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
+static phys_addr_t __init memblock_find_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
 {
        long i;
        phys_addr_t base = 0;
@@ -387,8 +377,6 @@ phys_addr_t __init __memblock_alloc_base(phys_addr_t size, phys_addr_t align, ph
 
        BUG_ON(0 == size);
 
-       size = memblock_align_up(size, align);
-
        /* Pump up max_addr */
        if (max_addr == MEMBLOCK_ALLOC_ACCESSIBLE)
                max_addr = memblock.current_limit;
@@ -405,13 +393,43 @@ phys_addr_t __init __memblock_alloc_base(phys_addr_t size, phys_addr_t align, ph
                        continue;
                base = min(memblockbase + memblocksize, max_addr);
                res_base = memblock_find_region(memblockbase, base, size, align);
-               if (res_base != MEMBLOCK_ERROR &&
-                   memblock_add_region(&memblock.reserved, res_base, size) >= 0)
+               if (res_base != MEMBLOCK_ERROR)
                        return res_base;
        }
+       return MEMBLOCK_ERROR;
+}
+
+phys_addr_t __init __memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
+{      
+       phys_addr_t found;
+
+       /* We align the size to limit fragmentation. Without this, a lot of
+        * small allocs quickly eat up the whole reserve array on sparc
+        */
+       size = memblock_align_up(size, align);
+
+       found = memblock_find_base(size, align, max_addr);
+       if (found != MEMBLOCK_ERROR &&
+           memblock_add_region(&memblock.reserved, found, size) >= 0)
+               return found;
+
        return 0;
 }
 
+phys_addr_t __init memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
+{
+       phys_addr_t alloc;
+
+       alloc = __memblock_alloc_base(size, align, max_addr);
+
+       if (alloc == 0)
+               panic("ERROR: Failed to allocate 0x%llx bytes below 0x%llx.\n",
+                     (unsigned long long) size, (unsigned long long) max_addr);
+
+       return alloc;
+}
+
+
 /* You must call memblock_analyze() before this. */
 phys_addr_t __init memblock_phys_mem_size(void)
 {