The patch titled Subject: mm, pcp: share common code between memory hotplug and percpu sysctl handler has been added to the -mm tree. Its filename is mm-pcp-share-common-code-between-memory-hotplug-and-percpu-sysctl-handler.patch

This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-pcp-share-common-code-between-me... and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-pcp-share-common-code-between-me...

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------------------------------------------------------ From: Mel Gorman mgorman@techsingularity.net Subject: mm, pcp: share common code between memory hotplug and percpu sysctl handler

Both the percpu_pagelist_fraction sysctl handler and memory hotplug have a common requirement of updating the pcpu page allocation batch and high values. Split the relevant helper to share common code.

No functional change.

Link: http://lkml.kernel.org/r/20191018105606.3249-2-mgorman@techsingularity.net Signed-off-by: Mel Gorman mgorman@techsingularity.net Tested-by: Matt Fleming matt@codeblueprint.co.uk Acked-by: Michal Hocko mhocko@suse.com Cc: Vlastimil Babka vbabka@suse.cz Cc: Thomas Gleixner tglx@linutronix.de Cc: Borislav Petkov bp@alien8.de Cc: stable@vger.kernel.org [4.1+] Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

mm/page_alloc.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-)

--- a/mm/page_alloc.c~mm-pcp-share-common-code-between-memory-hotplug-and-percpu-sysctl-handler +++ a/mm/page_alloc.c @@ -7985,6 +7985,15 @@ int lowmem_reserve_ratio_sysctl_handler( 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 @@ -8016,13 +8025,8 @@ int percpu_pagelist_fraction_sysctl_hand if (percpu_pagelist_fraction == old_percpu_pagelist_fraction) goto out;

- for_each_populated_zone(zone) { - unsigned int cpu; - - for_each_possible_cpu(cpu) - pageset_set_high_and_batch(zone, - per_cpu_ptr(zone->pageset, cpu)); - } + for_each_populated_zone(zone) + __zone_pcp_update(zone); out: mutex_unlock(&pcp_batch_high_lock); return ret; @@ -8521,11 +8525,8 @@ void free_contig_range(unsigned long pfn */ void __meminit zone_pcp_update(struct zone *zone) { - unsigned cpu; mutex_lock(&pcp_batch_high_lock); - for_each_possible_cpu(cpu) - pageset_set_high_and_batch(zone, - per_cpu_ptr(zone->pageset, cpu)); + __zone_pcp_update(zone); mutex_unlock(&pcp_batch_high_lock); } #endif _

Patches currently in -mm which might be from mgorman@techsingularity.net are

mm-pcp-share-common-code-between-memory-hotplug-and-percpu-sysctl-handler.patch mm-meminit-recalculate-pcpu-batch-and-high-limits-after-init-completes.patch mm-pcpu-make-zone-pcp-updates-and-reset-internal-to-the-mm.patch