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charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > We currently call pageset_set_high_and_batch() for each possible cpu, which > repeats the same calculations of high and batch values. > > Instead call the function just once per zone, and make it apply the calculated > values to all per-cpu pagesets of the zone. > > This also allows removing the zone_pageset_init() and __zone_pcp_update() > wrappers. > > No functional change. > > Signed-off-by: Vlastimil Babka > Reviewed-by: Oscar Salvador > Reviewed-by: David Hildenbrand > Acked-by: Michal Hocko > --- > mm/page_alloc.c | 42 ++++++++++++++++++------------------------ > 1 file changed, 18 insertions(+), 24 deletions(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 3f1c57344e73..2fa432762908 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -6307,13 +6307,14 @@ static void setup_pageset(struct per_cpu_pageset *p) > } > > /* > - * Calculate and set new high and batch values for given per-cpu pageset of a > + * Calculate and set new high and batch values for all per-cpu pagesets of a > * zone, based on the zone's size and the percpu_pagelist_fraction sysctl. > */ > -static void pageset_set_high_and_batch(struct zone *zone, > - struct per_cpu_pageset *p) > +static void zone_set_pageset_high_and_batch(struct zone *zone) > { > unsigned long new_high, new_batch; > + struct per_cpu_pageset *p; > + int cpu; > > if (percpu_pagelist_fraction) { > new_high = zone_managed_pages(zone) / percpu_pagelist_fraction; > @@ -6325,23 +6326,25 @@ static void pageset_set_high_and_batch(struct zone *zone, > new_high = 6 * new_batch; > new_batch = max(1UL, 1 * new_batch); > } > - pageset_update(&p->pcp, new_high, new_batch); > -} > - > -static void __meminit zone_pageset_init(struct zone *zone, int cpu) > -{ > - struct per_cpu_pageset *pcp = per_cpu_ptr(zone->pageset, cpu); > > - pageset_init(pcp); > - pageset_set_high_and_batch(zone, pcp); > + for_each_possible_cpu(cpu) { > + p = per_cpu_ptr(zone->pageset, cpu); > + pageset_update(&p->pcp, new_high, new_batch); > + } > } > > void __meminit setup_zone_pageset(struct zone *zone) > { > + struct per_cpu_pageset *p; > int cpu; > + > zone->pageset = alloc_percpu(struct per_cpu_pageset); > - for_each_possible_cpu(cpu) > - zone_pageset_init(zone, cpu); > + for_each_possible_cpu(cpu) { > + p = per_cpu_ptr(zone->pageset, cpu); > + pageset_init(p); > + } > + > + zone_set_pageset_high_and_batch(zone); > } > > /* > @@ -8080,15 +8083,6 @@ int lowmem_reserve_ratio_sysctl_handler(struct ctl_table *table, int write, > return 0; > } > > -static void __zone_pcp_update(struct zone *zone) > -{ > - unsigned int cpu; > - > - for_each_possible_cpu(cpu) > - pageset_set_high_and_batch(zone, > - per_cpu_ptr(zone->pageset, cpu)); > -} > - > /* > * percpu_pagelist_fraction - changes the pcp->high for each zone on each > * cpu. It is the fraction of total pages in each zone that a hot per cpu > @@ -8121,7 +8115,7 @@ int percpu_pagelist_fraction_sysctl_handler(struct ctl_table *table, int write, > goto out; > > for_each_populated_zone(zone) > - __zone_pcp_update(zone); > + zone_set_pageset_high_and_batch(zone); > out: > mutex_unlock(&pcp_batch_high_lock); > return ret; > @@ -8746,7 +8740,7 @@ EXPORT_SYMBOL(free_contig_range); > void __meminit zone_pcp_update(struct zone *zone) > { > mutex_lock(&pcp_batch_high_lock); > - __zone_pcp_update(zone); > + zone_set_pageset_high_and_batch(zone); > mutex_unlock(&pcp_batch_high_lock); > } Acked-by: Pankaj Gupta