Commit 496df3d3 authored by Ben Widawsky's avatar Ben Widawsky Committed by Linus Torvalds

mm: add comments on pglist_data zones

While making other modifications it was easy to confuse the two struct
members node_zones and node_zonelists.  For those already familiar with
the code, this might seem to be a silly patch, but it's quite helpful to
disambiguate the similar-sounding fields

While here, add a small comment on why nr_zones isn't simply MAX_NR_ZONES
Signed-off-by: default avatarBen Widawsky <ben.widawsky@intel.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200520205443.2757414-1-ben.widawsky@intel.comSigned-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent cc989e78
......@@ -660,9 +660,21 @@ struct deferred_split {
* per-zone basis.
*/
typedef struct pglist_data {
/*
* node_zones contains just the zones for THIS node. Not all of the
* zones may be populated, but it is the full list. It is referenced by
* this node's node_zonelists as well as other node's node_zonelists.
*/
struct zone node_zones[MAX_NR_ZONES];
/*
* node_zonelists contains references to all zones in all nodes.
* Generally the first zones will be references to this node's
* node_zones.
*/
struct zonelist node_zonelists[MAX_ZONELISTS];
int nr_zones;
int nr_zones; /* number of populated zones in this node */
#ifdef CONFIG_FLAT_NODE_MEM_MAP /* means !SPARSEMEM */
struct page *node_mem_map;
#ifdef CONFIG_PAGE_EXTENSION
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment