>-----Original Message-----
>From: owner-linux...@kvack.org [mailto:owner-linux...@kvack.org] On
>Behalf Of Xishi Qiu
>Sent: Thursday, April 25, 2019 11:26 AM
>To: Wu, Fengguang <fengguang...@intel.com>; Du, Fan <fan...@intel.com>
>Cc: a...@linux-foundation.org; Michal Hocko <mho...@suse.com>;
>Williams, Dan J <dan.j.willi...@intel.com>; Hansen, Dave
><dave.han...@intel.com>; Huang, Ying <ying.hu...@intel.com>;
>linux...@kvack.org; Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
>Subject: Re: [RFC PATCH 5/5] mm, page_alloc: Introduce
>ZONELIST_FALLBACK_SAME_TYPE fallback list
>
>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?
Yes, you are right. :)
>Thanks,
>Xishi Qiu
>>
>On system with heterogeneous memory, reasonable fall back lists wo
>ul 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...@intel.com>
>> ---
>> 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 up
>dating */
>>
>> /*
>> @@ -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_T
>YPE)
>>
>> /* Room for N __GFP_FOO bits */
>> #define __GFP_BITS_SHIFT (23 + IS_ENABLED(CONFIG_LOCKDEP))
>> @@ -301,6 +304,8 @@
>> __GFP_NOMEMALLOC | __GFP_NOWARN) & ~__GFP_RECLA
>IM)
>> #define GFP_TRANSHUGE (GFP_TRANSHUGE_LIGHT | __GFP_DIRE
>CT_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_MOVA
>BLE)
>> #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 sam
>e type node */
>> #ifdef CONFIG_NUMA
>> /*
>> * The NUMA zonelists are doubled because we need zonel
>ists 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]._zon
>erefs;
>> +
>> + 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
>>
>>
