From: Vlastimil Babka <vbabka@xxxxxxx> Subject: mm, page_alloc: remove setup_pageset() We initialize boot-time pagesets with setup_pageset(), which sets high and batch values that effectively disable pcplists. We can remove this wrapper if we just set these values for all pagesets in pageset_init(). Non-boot pagesets then subsequently update them to the proper values. No functional change. Link: https://lkml.kernel.org/r/20201111092812.11329-4-vbabka@xxxxxxx Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx> Reviewed-by: David Hildenbrand <david@xxxxxxxxxx> Reviewed-by: Oscar Salvador <osalvador@xxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Acked-by: Pankaj Gupta <pankaj.gupta@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/page_alloc.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) --- a/mm/page_alloc.c~mm-page_alloc-remove-setup_pageset +++ a/mm/page_alloc.c @@ -5919,7 +5919,7 @@ static void build_zonelists(pg_data_t *p * not check if the processor is online before following the pageset pointer. * Other parts of the kernel may not check if the zone is available. */ -static void setup_pageset(struct per_cpu_pageset *p); +static void pageset_init(struct per_cpu_pageset *p); static DEFINE_PER_CPU(struct per_cpu_pageset, boot_pageset); static DEFINE_PER_CPU(struct per_cpu_nodestat, boot_nodestats); @@ -5987,7 +5987,7 @@ build_all_zonelists_init(void) * (a chicken-egg dilemma). */ for_each_possible_cpu(cpu) - setup_pageset(&per_cpu(boot_pageset, cpu)); + pageset_init(&per_cpu(boot_pageset, cpu)); mminit_verify_zonelist(); cpuset_init_current_mems_allowed(); @@ -6306,12 +6306,15 @@ static void pageset_init(struct per_cpu_ pcp = &p->pcp; for (migratetype = 0; migratetype < MIGRATE_PCPTYPES; migratetype++) INIT_LIST_HEAD(&pcp->lists[migratetype]); -} -static void setup_pageset(struct per_cpu_pageset *p) -{ - pageset_init(p); - pageset_update(&p->pcp, 0, 1); + /* + * Set batch and high values safe for a boot pageset. A true percpu + * pageset's initialization will update them subsequently. Here we don't + * need to be as careful as pageset_update() as nobody can access the + * pageset yet. + */ + pcp->high = 0; + pcp->batch = 1; } /* _
