From: "Dennis Zhou (Facebook)" <dennisszhou@xxxxxxxxx>
With moving the base_addr in the chunks responsible for serving the
first chunk up, the use of schunk/dchunk in pcpu_setup_first_chunk no
longer makes sense. This makes the linking in the first chunk code not
rely on a ternary and renames the variables to a shared variable, chunk,
because the allocation path is sequential.
Signed-off-by: Dennis Zhou <dennisszhou@xxxxxxxxx>
---
mm/percpu.c | 96 ++++++++++++++++++++++++++++++-------------------------------
1 file changed, 48 insertions(+), 48 deletions(-)
diff --git a/mm/percpu.c b/mm/percpu.c
index c74ad68..9dd28a2 100644
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -1597,7 +1597,7 @@ int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
static int dmap[PERCPU_DYNAMIC_EARLY_SLOTS] __initdata;
size_t dyn_size = ai->dyn_size;
size_t size_sum = ai->static_size + ai->reserved_size + dyn_size;
- struct pcpu_chunk *schunk, *dchunk = NULL;
+ struct pcpu_chunk *chunk;
unsigned long *group_offsets;
size_t *group_sizes;
unsigned long *unit_off;
@@ -1709,13 +1709,13 @@ int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
INIT_LIST_HEAD(&pcpu_slot[i]);
/*
- * Initialize static chunk.
- * The static region is dropped as those addresses are already
- * allocated and do not rely on chunk->base_addr.
- * reserved_size == 0:
- * the static chunk covers the dynamic area
- * reserved_size > 0:
- * the static chunk covers the reserved area
+ * Initialize first chunk.
+ * pcpu_first_chunk will always manage the dynamic region of the
+ * first chunk. The static region is dropped as those addresses
+ * are already allocated and do not rely on chunk->base_addr.
+ *
+ * ai->reserved == 0:
+ * reserved_chunk == NULL;
*
* If the static area is not page aligned, the region adjacent
* to the static area must have its base_addr be offset into
@@ -1730,61 +1730,61 @@ int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
map_size_bytes = (ai->reserved_size ?: ai->dyn_size) +
pcpu_reserved_offset;
- /* schunk 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 = (void *)aligned_addr;
- 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;
+ /* chunk adjacent to static region allocation */
+ chunk = memblock_virt_alloc(pcpu_chunk_struct_size, 0);
+ INIT_LIST_HEAD(&chunk->list);
+ INIT_LIST_HEAD(&chunk->map_extend_list);
+ chunk->base_addr = (void *)aligned_addr;
+ chunk->map = smap;
+ chunk->map_alloc = ARRAY_SIZE(smap);
+ chunk->immutable = true;
+ bitmap_fill(chunk->populated, pcpu_unit_pages);
+ chunk->nr_populated = pcpu_unit_pages;
- schunk->nr_pages = map_size_bytes >> PAGE_SHIFT;
+ chunk->nr_pages = map_size_bytes >> PAGE_SHIFT;
if (ai->reserved_size) {
- schunk->free_size = ai->reserved_size;
- pcpu_reserved_chunk = schunk;
+ chunk->free_size = ai->reserved_size;
+ pcpu_reserved_chunk = chunk;
} else {
- schunk->free_size = dyn_size;
+ chunk->free_size = dyn_size;
dyn_size = 0; /* dynamic area covered */
}
- schunk->contig_hint = schunk->free_size;
+ chunk->contig_hint = chunk->free_size;
if (pcpu_reserved_offset) {
- schunk->has_reserved = true;
- schunk->map[0] = 1;
- schunk->map[1] = pcpu_reserved_offset;
- schunk->map_used = 1;
+ chunk->has_reserved = true;
+ chunk->map[0] = 1;
+ chunk->map[1] = pcpu_reserved_offset;
+ chunk->map_used = 1;
}
- if (schunk->free_size)
- schunk->map[++schunk->map_used] = map_size_bytes;
- schunk->map[schunk->map_used] |= 1;
+ if (chunk->free_size)
+ chunk->map[++chunk->map_used] = map_size_bytes;
+ chunk->map[chunk->map_used] |= 1;
- /* init dynamic chunk if necessary */
+ /* init dynamic region of first chunk if necessary */
if (dyn_size) {
- 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 + ai->static_size +
+ 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 + 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 = dyn_size;
- dchunk->map[0] = 0;
- dchunk->map[1] = dchunk->free_size | 1;
- dchunk->map_used = 1;
-
- dchunk->nr_pages = dyn_size >> PAGE_SHIFT;
+ chunk->map = dmap;
+ chunk->map_alloc = ARRAY_SIZE(dmap);
+ chunk->immutable = true;
+ bitmap_fill(chunk->populated, pcpu_unit_pages);
+ chunk->nr_populated = pcpu_unit_pages;
+
+ chunk->contig_hint = chunk->free_size = dyn_size;
+ chunk->map[0] = 0;
+ chunk->map[1] = chunk->free_size | 1;
+ chunk->map_used = 1;
+
+ chunk->nr_pages = dyn_size >> PAGE_SHIFT;
}
/* link the first chunk in */
- pcpu_first_chunk = dchunk ?: schunk;
+ pcpu_first_chunk = chunk;
pcpu_nr_empty_pop_pages +=
pcpu_count_occupied_pages(pcpu_first_chunk, 1);
pcpu_chunk_relocate(pcpu_first_chunk, -1);
--
2.9.3
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