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

[Du, Fan]

>-----Original Message-----
>From: owner-linux-mm@xxxxxxxxx [mailto:owner-linux-mm@xxxxxxxxx] On
>Behalf Of Xishi Qiu
>Sent: Thursday, April 25, 2019 11:26 AM
>To: Wu, Fengguang <fengguang.wu@xxxxxxxxx>; Du, Fan <fan.du@xxxxxxxxx>
>Cc: akpm@xxxxxxxxxxxxxxxxxxxx; Michal Hocko <mhocko@xxxxxxxx>;
>Williams, Dan J <dan.j.williams@xxxxxxxxx>; Hansen, Dave
><dave.hansen@xxxxxxxxx>; Huang, Ying <ying.huang@xxxxxxxxx>;
>linux-mm@xxxxxxxxx; Linux Kernel Mailing List <linux-kernel@xxxxxxxxxxxxxxx>
>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
>>
>OnÂsystemÂwithÂheterogeneousÂmemory,ÂreasonableÂfallÂbackÂlistsÂwo
>ulÂbe:
>>     a.ÂNoÂfallÂback,ÂstickÂtoÂcurrentÂrunningÂnode.
>>
>b.ÂFallÂbackÂtoÂotherÂnodesÂofÂtheÂsameÂtypeÂorÂdifferentÂtype
>>     ÂÂÂe.g.ÂDRAMÂnodeÂ0Â->ÂDRAMÂnodeÂ1Â->ÂPMEMÂnodeÂ2Â->
>PMEMÂnodeÂ3
>>     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_SHIFTÂmayÂneedÂup
>datingÂ*/
>>
>>     Â/*
>>     @@Â-215,6Â+217,7Â@@
>>
>>     Â/*ÂDisableÂlockdepÂforÂGFPÂcontextÂtrackingÂ*/
>>     Â#defineÂ__GFP_NOLOCKDEPÂ((__forceÂgfp_t)___GFP_NOLOCKDEP)
>>
>+#defineÂ__GFP_SAME_NODE_TYPEÂ((__forceÂgfp_t)___GFP_SAME_NODE_T
>YPE)
>>
>>     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_RECLA
>IM)
>>     Â#defineÂGFP_TRANSHUGEÂ(GFP_TRANSHUGE_LIGHTÂ|Â__GFP_DIRE
>CT_RECLAIM)
>>
>>     +#defineÂGFP_SAME_NODE_TYPEÂ(__GFP_SAME_NODE_TYPE)
>>     +
>>     Â/*ÂConvertÂGFPÂflagsÂtoÂtheirÂcorrespondingÂmigrateÂtypeÂ*/
>>     Â#defineÂGFP_MOVABLE_MASKÂ(__GFP_RECLAIMABLE|__GFP_MOVA
>BLE)
>>     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(structÂzone
>*zone,
>>
>>     ÂenumÂ{
>>     ÂÂZONELIST_FALLBACK,Â/*ÂzonelistÂwithÂfallbackÂ*/
>>
>+ÂZONELIST_FALLBACK_SAME_TYPE,Â/*ÂzonelistÂwithÂfallbackÂtoÂtheÂsam
>eÂtypeÂnodeÂ*/
>>     Â#ifdefÂCONFIG_NUMA
>>     ÂÂ/*
>>     ÂÂÂ*ÂTheÂNUMAÂzonelistsÂareÂdoubledÂbecauseÂweÂneedÂzonel
>istsÂthat
>>     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]._zon
>erefs;
>>     +
>>     +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/*
>>     --
>>     1.8.3.1
>>
>>