Re: [RFC PATCH 5/5] mm, page_alloc: Introduce ZONELIST_FALLBACK_SAME_TYPE fallback list

[Xishi Qiu]

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
>     OnÂsystemÂwithÂheterogeneousÂmemory,ÂreasonableÂfallÂbackÂlistsÂwoulÂbe:
>     a.ÂNoÂfallÂback,ÂstickÂtoÂcurrentÂrunningÂnode.
>     b.ÂFallÂbackÂtoÂotherÂnodesÂofÂtheÂsameÂtypeÂorÂdifferentÂtype
>     ÂÂÂe.g.ÂDRAMÂnodeÂ0Â->ÂDRAMÂnodeÂ1Â->ÂPMEMÂnodeÂ2Â->ÂPMEMÂnodeÂ3
>     c.ÂFallÂbackÂtoÂotherÂnodesÂofÂtheÂsameÂtypeÂonly.
>     ÂÂÂe.g.ÂDRAMÂnodeÂ0Â->ÂDRAMÂnodeÂ1
> 
>     a.ÂisÂalreadyÂinÂplace,ÂpreviousÂpatchÂimplementÂb.ÂprovidingÂwayÂto
>     satisfyÂmemoryÂrequestÂasÂbestÂeffortÂbyÂdefault.ÂAndÂthisÂpatchÂof
>     writingÂbuildÂc.ÂtoÂfallbackÂtoÂtheÂsameÂnodeÂtypeÂwhenÂuserÂspecify
>     GFP_SAME_NODE_TYPEÂonly.
> 
>     Signed-off-by:ÂFanÂDuÂ<fan.du@xxxxxxxxx>
>     ---
>     Âinclude/linux/gfp.hÂÂÂÂ|ÂÂ7Â+++++++
>     Âinclude/linux/mmzone.hÂ|ÂÂ1Â+
>     Âmm/page_alloc.cÂÂÂÂÂÂÂÂ|Â15Â+++++++++++++++
>     Â3ÂfilesÂchanged,Â23Âinsertions(+)
> 
>     diffÂ--gitÂa/include/linux/gfp.hÂb/include/linux/gfp.h
>     indexÂfdab7de..ca5fdfcÂ100644
>     ---Âa/include/linux/gfp.h
>     +++Âb/include/linux/gfp.h
>     @@Â-44,6Â+44,8Â@@
>     Â#else
>     Â#defineÂ___GFP_NOLOCKDEPÂ0
>     Â#endif
>     +#defineÂ___GFP_SAME_NODE_TYPEÂ0x1000000u
>     +
>     Â/*ÂIfÂtheÂaboveÂareÂmodified,Â__GFP_BITS_SHIFTÂmayÂneedÂupdatingÂ*/
>     Â
>     Â/*
>     @@Â-215,6Â+217,7Â@@
>     Â
>     Â/*ÂDisableÂlockdepÂforÂGFPÂcontextÂtrackingÂ*/
>     Â#defineÂ__GFP_NOLOCKDEPÂ((__forceÂgfp_t)___GFP_NOLOCKDEP)
>     +#defineÂ__GFP_SAME_NODE_TYPEÂ((__forceÂgfp_t)___GFP_SAME_NODE_TYPE)
>     Â
>     Â/*ÂRoomÂforÂNÂ__GFP_FOOÂbitsÂ*/
>     Â#defineÂ__GFP_BITS_SHIFTÂ(23Â+ÂIS_ENABLED(CONFIG_LOCKDEP))
>     @@Â-301,6Â+304,8Â@@
>     ÂÂÂÂÂ__GFP_NOMEMALLOCÂ|Â__GFP_NOWARN)Â&Â~__GFP_RECLAIM)
>     Â#defineÂGFP_TRANSHUGEÂ(GFP_TRANSHUGE_LIGHTÂ|Â__GFP_DIRECT_RECLAIM)
>     Â
>     +#defineÂGFP_SAME_NODE_TYPEÂ(__GFP_SAME_NODE_TYPE)
>     +
>     Â/*ÂConvertÂGFPÂflagsÂtoÂtheirÂcorrespondingÂmigrateÂtypeÂ*/
>     Â#defineÂGFP_MOVABLE_MASKÂ(__GFP_RECLAIMABLE|__GFP_MOVABLE)
>     Â#defineÂGFP_MOVABLE_SHIFTÂ3
>     @@Â-438,6Â+443,8Â@@ÂstaticÂinlineÂintÂgfp_zonelist(gfp_tÂflags)
>     Â#ifdefÂCONFIG_NUMA
>     ÂÂifÂ(unlikely(flagsÂ&Â__GFP_THISNODE))
>     ÂÂÂreturnÂZONELIST_NOFALLBACK;
>     +ÂifÂ(unlikely(flagsÂ&Â__GFP_SAME_NODE_TYPE))
>     +ÂÂreturnÂZONELIST_FALLBACK_SAME_TYPE;
>     Â#endif
>     ÂÂreturnÂZONELIST_FALLBACK;
>     Â}
>     diffÂ--gitÂa/include/linux/mmzone.hÂb/include/linux/mmzone.h
>     indexÂ8c37e1c..2f8603eÂ100644
>     ---Âa/include/linux/mmzone.h
>     +++Âb/include/linux/mmzone.h
>     @@Â-583,6Â+583,7Â@@ÂstaticÂinlineÂboolÂzone_intersects(structÂzoneÂ*zone,
>     Â
>     ÂenumÂ{
>     ÂÂZONELIST_FALLBACK,Â/*ÂzonelistÂwithÂfallbackÂ*/
>     +ÂZONELIST_FALLBACK_SAME_TYPE,Â/*ÂzonelistÂwithÂfallbackÂtoÂtheÂsameÂtypeÂnodeÂ*/
>     Â#ifdefÂCONFIG_NUMA
>     ÂÂ/*
>     ÂÂÂ*ÂTheÂNUMAÂzonelistsÂareÂdoubledÂbecauseÂweÂneedÂzonelistsÂthat
>     diffÂ--gitÂa/mm/page_alloc.cÂb/mm/page_alloc.c
>     indexÂa408a91..de797921Â100644
>     ---Âa/mm/page_alloc.c
>     +++Âb/mm/page_alloc.c
>     @@Â-5448,6Â+5448,21Â@@ÂstaticÂvoidÂbuild_zonelists_in_node_order(pg_data_tÂ*pgdat,ÂintÂ*node_order,
>     ÂÂ}
>     ÂÂzonerefs->zoneÂ=ÂNULL;
>     ÂÂzonerefs->zone_idxÂ=Â0;
>     +
>     +ÂzonerefsÂ=Âpgdat->node_zonelists[ZONELIST_FALLBACK_SAME_TYPE]._zonerefs;
>     +
>     +ÂforÂ(iÂ=Â0;ÂiÂ<Ânr_nodes;Âi++)Â{
>     +ÂÂintÂnr_zones;
>     +
>     +ÂÂpg_data_tÂ*nodeÂ=ÂNODE_DATA(node_order[i]);
>     +
>     +ÂÂifÂ(!is_node_same_type(node->node_id,Âpgdat->node_id))
>     +ÂÂÂcontinue;
>     +ÂÂnr_zonesÂ=Âbuild_zonerefs_node(node,Âzonerefs);
>     +ÂÂzonerefsÂ+=Ânr_zones;
>     +Â}
>     +Âzonerefs->zoneÂ=ÂNULL;
>     +Âzonerefs->zone_idxÂ=Â0;
>     Â}
>     Â
>     Â/*
>     --Â
>     1.8.3.1
> 
>