The patch titled ZVC: Overstep counters has been removed from the -mm tree. Its filename is zvc-overstep-counters.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ Subject: ZVC: Overstep counters From: Christoph Lameter <clameter@xxxxxxx> Increments and decrements are usually grouped rather than mixed. We can optimize the inc and dec functions for that case. Increment and decrement the counters by 50% more than the threshold in those cases and set the differential accordingly. This decreases the need to update the atomic counters. The idea came originally from Andrew Morton. The overstepping alone was sufficient to address the contention issue found when updating the global and the per zone counters from 160 processors. Also remove some code in dec_zone_page_state. Signed-off-by: Christoph Lameter <clameter@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxx> --- mm/vmstat.c | 20 +++++--------------- 1 file changed, 5 insertions(+), 15 deletions(-) diff -puN mm/vmstat.c~zvc-overstep-counters mm/vmstat.c --- a/mm/vmstat.c~zvc-overstep-counters +++ a/mm/vmstat.c @@ -190,8 +190,8 @@ static void __inc_zone_state(struct zone (*p)++; if (unlikely(*p > STAT_THRESHOLD)) { - zone_page_state_add(*p, zone, item); - *p = 0; + zone_page_state_add(*p + STAT_THRESHOLD / 2, zone, item); + *p = -STAT_THRESHOLD / 2; } } @@ -209,8 +209,8 @@ void __dec_zone_page_state(struct page * (*p)--; if (unlikely(*p < -STAT_THRESHOLD)) { - zone_page_state_add(*p, zone, item); - *p = 0; + zone_page_state_add(*p - STAT_THRESHOLD / 2, zone, item); + *p = STAT_THRESHOLD /2; } } EXPORT_SYMBOL(__dec_zone_page_state); @@ -239,19 +239,9 @@ EXPORT_SYMBOL(inc_zone_page_state); void dec_zone_page_state(struct page *page, enum zone_stat_item item) { unsigned long flags; - struct zone *zone; - s8 *p; - zone = page_zone(page); local_irq_save(flags); - p = diff_pointer(zone, item); - - (*p)--; - - if (unlikely(*p < -STAT_THRESHOLD)) { - zone_page_state_add(*p, zone, item); - *p = 0; - } + __dec_zone_page_state(page, item); local_irq_restore(flags); } EXPORT_SYMBOL(dec_zone_page_state); _ Patches currently in -mm which might be from clameter@xxxxxxx are origin.patch page-migration-replace-radix_tree_lookup_slot-with-radix_tree_lockup.patch reduce-max_nr_zones-remove-two-strange-uses-of-max_nr_zones.patch reduce-max_nr_zones-fix-max_nr_zones-array-initializations.patch reduce-max_nr_zones-make-display-of-highmem-counters-conditional-on-config_highmem.patch reduce-max_nr_zones-make-display-of-highmem-counters-conditional-on-config_highmem-tidy.patch reduce-max_nr_zones-move-highmem-counters-into-highmemc-h.patch reduce-max_nr_zones-move-highmem-counters-into-highmemc-h-fix.patch reduce-max_nr_zones-page-allocator-zone_highmem-cleanup.patch reduce-max_nr_zones-use-enum-to-define-zones-reformat-and-comment.patch reduce-max_nr_zones-use-enum-to-define-zones-reformat-and-comment-cleanup.patch reduce-max_nr_zones-make-zone_dma32-optional.patch reduce-max_nr_zones-make-zone_highmem-optional.patch reduce-max_nr_zones-make-zone_highmem-optional-fix.patch reduce-max_nr_zones-make-zone_highmem-optional-fix-fix.patch reduce-max_nr_zones-remove-display-of-counters-for-unconfigured-zones.patch reduce-max_nr_zones-fix-i386-srat-check-for-max_nr_zones.patch mempolicies-fix-policy_zone-check.patch apply-type-enum-zone_type.patch apply-type-enum-zone_type-fix.patch linearly-index-zone-node_zonelists.patch slab-respect-architecture-and-caller-mandated-alignment.patch slab-optimize-kmalloc_node-the-same-way-as-kmalloc.patch slab-optimize-kmalloc_node-the-same-way-as-kmalloc-fix.patch slab-extract-__kmem_cache_destroy-from-kmem_cache_destroy.patch slab-do-not-panic-when-alloc_kmemlist-fails-and-slab-is-up.patch add-__gfp_thisnode-to-avoid-fallback-to-other-nodes-and-ignore.patch add-__gfp_thisnode-to-avoid-fallback-to-other-nodes-and-ignore-fix.patch sys_move_pages-do-not-fall-back-to-other-nodes.patch guarantee-that-the-uncached-allocator-gets-pages-on-the-correct.patch cleanup-add-zone-pointer-to-get_page_from_freelist.patch profiling-require-buffer-allocation-on-the-correct-node.patch define-easier-to-handle-gfp_thisnode.patch optimize-free_one_page.patch do-not-check-unpopulated-zones-for-draining-and-counter.patch extract-the-allocpercpu-functions-from-the-slab-allocator.patch replace-min_unmapped_ratio-by-min_unmapped_pages-in-struct-zone.patch zvc-support-nr_slab_reclaimable--nr_slab_unreclaimable.patch zone_reclaim-dynamic-slab-reclaim.patch zone_reclaim-dynamic-slab-reclaim-tidy.patch zone-reclaim-with-slab-avoid-unecessary-off-node-allocations.patch x86-implement-always-locked-bit-ops-for-memory-shared-with-an-smp-hypervisor.patch zvc-support-nr_slab_reclaimable--nr_slab_unreclaimable-swap_prefetch.patch reduce-max_nr_zones-swap_prefetch-remove-incorrect-use-of-zone_highmem.patch readahead-state-based-method-aging-accounting-apply-type-enum-zone_type-readahead.patch -- VGER BF report: U 0.5 - To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html