percpu: unify allocation of schunk and dchunk

Create a common allocator for first chunk initialization,
pcpu_alloc_first_chunk. Comments for this function will be added in a
later patch once the bitmap allocator is added.

Signed-off-by: Dennis Zhou <dennisszhou@gmail.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

diff --git a/mm/percpu.c b/mm/percpu.c
index 851aa81097882b6c7237a8aaf5ebef91803a3329..2e785a77ce14d9a34582103384ff220840f8cefe 100644 (file)
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -708,6 +708,36 @@ static void pcpu_free_area(struct pcpu_chunk *chunk, int freeme,
        pcpu_chunk_relocate(chunk, oslot);
 }
 
+static struct pcpu_chunk * __init pcpu_alloc_first_chunk(void *base_addr,
+                                                        int start_offset,
+                                                        int map_size,
+                                                        int *map,
+                                                        int init_map_size)
+{
+       struct pcpu_chunk *chunk;
+
+       chunk = memblock_virt_alloc(pcpu_chunk_struct_size, 0);
+       INIT_LIST_HEAD(&chunk->list);
+       INIT_LIST_HEAD(&chunk->map_extend_list);
+       chunk->base_addr = base_addr;
+       chunk->start_offset = start_offset;
+       chunk->map = map;
+       chunk->map_alloc = init_map_size;
+
+       /* manage populated page bitmap */
+       chunk->immutable = true;
+       bitmap_fill(chunk->populated, pcpu_unit_pages);
+       chunk->nr_populated = pcpu_unit_pages;
+
+       chunk->contig_hint = chunk->free_size = map_size;
+       chunk->map[0] = 1;
+       chunk->map[1] = chunk->start_offset;
+       chunk->map[2] = (chunk->start_offset + chunk->free_size) | 1;
+       chunk->map_used = 2;
+
+       return chunk;
+}
+
 static struct pcpu_chunk *pcpu_alloc_chunk(void)
 {
        struct pcpu_chunk *chunk;
@@ -1570,6 +1600,7 @@ int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
        unsigned int cpu;
        int *unit_map;
        int group, unit, i;
+       int map_size, start_offset;
 
 #define PCPU_SETUP_BUG_ON(cond)        do {                                    \
        if (unlikely(cond)) {                                           \
@@ -1678,44 +1709,20 @@ int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
         * covers static area + reserved area (mostly used for module
         * static percpu allocation).
         */
-       schunk = memblock_virt_alloc(pcpu_chunk_struct_size, 0);
-       INIT_LIST_HEAD(&schunk->list);
-       INIT_LIST_HEAD(&schunk->map_extend_list);
-       schunk->base_addr = base_addr;
-       schunk->start_offset = ai->static_size;
-       schunk->map = smap;
-       schunk->map_alloc = ARRAY_SIZE(smap);
-       schunk->immutable = true;
-       bitmap_fill(schunk->populated, pcpu_unit_pages);
-       schunk->nr_populated = pcpu_unit_pages;
-
-       schunk->free_size = ai->reserved_size ?: ai->dyn_size;
-       schunk->contig_hint = schunk->free_size;
-       schunk->map[0] = 1;
-       schunk->map[1] = schunk->start_offset;
-       schunk->map[2] = (ai->static_size + schunk->free_size) | 1;
-       schunk->map_used = 2;
+       start_offset = ai->static_size;
+       map_size = ai->reserved_size ?: ai->dyn_size;
+       schunk = pcpu_alloc_first_chunk(base_addr, start_offset, map_size,
+                                       smap, ARRAY_SIZE(smap));
 
        /* init dynamic chunk if necessary */
        if (ai->reserved_size) {
                pcpu_reserved_chunk = schunk;
 
-               dchunk = memblock_virt_alloc(pcpu_chunk_struct_size, 0);
-               INIT_LIST_HEAD(&dchunk->list);
-               INIT_LIST_HEAD(&dchunk->map_extend_list);
-               dchunk->base_addr = base_addr;
-               dchunk->start_offset = ai->static_size + ai->reserved_size;
-               dchunk->map = dmap;
-               dchunk->map_alloc = ARRAY_SIZE(dmap);
-               dchunk->immutable = true;
-               bitmap_fill(dchunk->populated, pcpu_unit_pages);
-               dchunk->nr_populated = pcpu_unit_pages;
-
-               dchunk->contig_hint = dchunk->free_size = ai->dyn_size;
-               dchunk->map[0] = 1;
-               dchunk->map[1] = dchunk->start_offset;
-               dchunk->map[2] = (dchunk->start_offset + dchunk->free_size) | 1;
-               dchunk->map_used = 2;
+               start_offset = ai->static_size + ai->reserved_size;
+               map_size = ai->dyn_size;
+               dchunk = pcpu_alloc_first_chunk(base_addr, start_offset,
+                                               map_size, dmap,
+                                               ARRAY_SIZE(dmap));
        }
 
        /* link the first chunk in */