Hi Fan Du,
I think we should change the print in mminit_verify_zonelist too.
This patch changes the order of ZONELIST_FALLBACK, so the default numa policy can
alloc DRAM first, then PMEM, right?
Thanks,
Xishi Qiu
> On system with heterogeneous memory, reasonable fall back lists woul be:
> a. No fall back, stick to current running node.
> b. Fall back to other nodes of the same type or different type
> e.g. DRAM node 0 -> DRAM node 1 -> PMEM node 2 -> PMEM node 3
> c. Fall back to other nodes of the same type only.
> e.g. DRAM node 0 -> DRAM node 1
>
> a. is already in place, previous patch implement b. providing way to
> satisfy memory request as best effort by default. And this patch of
> writing build c. to fallback to the same node type when user specify
> GFP_SAME_NODE_TYPE only.
>
> Signed-off-by: Fan Du <fan.du@xxxxxxxxx>
> ---
> include/linux/gfp.h | 7 +++++++
> include/linux/mmzone.h | 1 +
> mm/page_alloc.c | 15 +++++++++++++++
> 3 files changed, 23 insertions(+)
>
> diff --git a/include/linux/gfp.h b/include/linux/gfp.h
> index fdab7de..ca5fdfc 100644
> --- a/include/linux/gfp.h
> +++ b/include/linux/gfp.h
> @@ -44,6 +44,8 @@
> #else
> #define ___GFP_NOLOCKDEP 0
> #endif
> +#define ___GFP_SAME_NODE_TYPE 0x1000000u
> +
> /* If the above are modified, __GFP_BITS_SHIFT may need updating */
>
> /*
> @@ -215,6 +217,7 @@
>
> /* Disable lockdep for GFP context tracking */
> #define __GFP_NOLOCKDEP ((__force gfp_t)___GFP_NOLOCKDEP)
> +#define __GFP_SAME_NODE_TYPE ((__force gfp_t)___GFP_SAME_NODE_TYPE)
>
> /* Room for N __GFP_FOO bits */
> #define __GFP_BITS_SHIFT (23 + IS_ENABLED(CONFIG_LOCKDEP))
> @@ -301,6 +304,8 @@
> __GFP_NOMEMALLOC | __GFP_NOWARN) & ~__GFP_RECLAIM)
> #define GFP_TRANSHUGE (GFP_TRANSHUGE_LIGHT | __GFP_DIRECT_RECLAIM)
>
> +#define GFP_SAME_NODE_TYPE (__GFP_SAME_NODE_TYPE)
> +
> /* Convert GFP flags to their corresponding migrate type */
> #define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE)
> #define GFP_MOVABLE_SHIFT 3
> @@ -438,6 +443,8 @@ static inline int gfp_zonelist(gfp_t flags)
> #ifdef CONFIG_NUMA
> if (unlikely(flags & __GFP_THISNODE))
> return ZONELIST_NOFALLBACK;
> + if (unlikely(flags & __GFP_SAME_NODE_TYPE))
> + return ZONELIST_FALLBACK_SAME_TYPE;
> #endif
> return ZONELIST_FALLBACK;
> }
> diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
> index 8c37e1c..2f8603e 100644
> --- a/include/linux/mmzone.h
> +++ b/include/linux/mmzone.h
> @@ -583,6 +583,7 @@ static inline bool zone_intersects(struct zone *zone,
>
> enum {
> ZONELIST_FALLBACK, /* zonelist with fallback */
> + ZONELIST_FALLBACK_SAME_TYPE, /* zonelist with fallback to the same type node */
> #ifdef CONFIG_NUMA
> /*
> * The NUMA zonelists are doubled because we need zonelists that
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index a408a91..de797921 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -5448,6 +5448,21 @@ static void build_zonelists_in_node_order(pg_data_t *pgdat, int *node_order,
> }
> zonerefs->zone = NULL;
> zonerefs->zone_idx = 0;
> +
> + zonerefs = pgdat->node_zonelists[ZONELIST_FALLBACK_SAME_TYPE]._zonerefs;
> +
> + for (i = 0; i < nr_nodes; i++) {
> + int nr_zones;
> +
> + pg_data_t *node = NODE_DATA(node_order[i]);
> +
> + if (!is_node_same_type(node->node_id, pgdat->node_id))
> + continue;
> + nr_zones = build_zonerefs_node(node, zonerefs);
> + zonerefs += nr_zones;
> + }
> + zonerefs->zone = NULL;
> + zonerefs->zone_idx = 0;
> }
>
> /*
> --
> 1.8.3.1
>
>
