Brilliant way to do split-counters based on the existing hashes :) Merged, thanks !
Mathieu * Lai Jiangshan ([email protected]) wrote: > Signed-off-by: Lai Jiangshan <[email protected]> > --- > rculfhash.c | 50 ++++++++++++++++++++++++++++---------------------- > 1 files changed, 28 insertions(+), 22 deletions(-) > > diff --git a/rculfhash.c b/rculfhash.c > index d1bec03..ea6df05 100644 > --- a/rculfhash.c > +++ b/rculfhash.c > @@ -506,7 +506,7 @@ void cds_lfht_resize_lazy(struct cds_lfht *ht, unsigned > long size, int growth); > * In the unfortunate event the number of CPUs reported would be > * inaccurate, we use modulo arithmetic on the number of CPUs we got. > */ > -#if defined(HAVE_SCHED_GETCPU) && defined(HAVE_SYSCONF) > +#if defined(HAVE_SYSCONF) > > static > void cds_lfht_resize_lazy_count(struct cds_lfht *ht, unsigned long size, > @@ -554,30 +554,36 @@ void free_split_items_count(struct ht_items_count > *count) > poison_free(count); > } > > +#if defined(HAVE_SCHED_GETCPU) > static > -int ht_get_split_count_index(void) > +int ht_get_split_count_index(unsigned long hash) > { > int cpu; > > assert(split_count_mask >= 0); > cpu = sched_getcpu(); > if (unlikely(cpu < 0)) > - return cpu; > + return hash & split_count_mask; > else > return cpu & split_count_mask; > } > +#else /* #if defined(HAVE_SCHED_GETCPU) */ > +static > +int ht_get_split_count_index(unsigned long hash) > +{ > + return hash & split_count_mask; > +} > +#endif /* #else #if defined(HAVE_SCHED_GETCPU) */ > > static > -void ht_count_add(struct cds_lfht *ht, unsigned long size) > +void ht_count_add(struct cds_lfht *ht, unsigned long size, unsigned long > hash) > { > unsigned long split_count; > int index; > > if (unlikely(!ht->split_count)) > return; > - index = ht_get_split_count_index(); > - if (unlikely(index < 0)) > - return; > + index = ht_get_split_count_index(hash); > split_count = uatomic_add_return(&ht->split_count[index].add, 1); > if (unlikely(!(split_count & ((1UL << COUNT_COMMIT_ORDER) - 1)))) { > long count; > @@ -597,16 +603,14 @@ void ht_count_add(struct cds_lfht *ht, unsigned long > size) > } > > static > -void ht_count_del(struct cds_lfht *ht, unsigned long size) > +void ht_count_del(struct cds_lfht *ht, unsigned long size, unsigned long > hash) > { > unsigned long split_count; > int index; > > if (unlikely(!ht->split_count)) > return; > - index = ht_get_split_count_index(); > - if (unlikely(index < 0)) > - return; > + index = ht_get_split_count_index(hash); > split_count = uatomic_add_return(&ht->split_count[index].del, 1); > if (unlikely(!(split_count & ((1UL << COUNT_COMMIT_ORDER) - 1)))) { > long count; > @@ -631,7 +635,7 @@ void ht_count_del(struct cds_lfht *ht, unsigned long size) > } > } > > -#else /* #if defined(HAVE_SCHED_GETCPU) && defined(HAVE_SYSCONF) */ > +#else /* #if defined(HAVE_SYSCONF) */ > > static const long nr_cpus_mask = -2; > static const long split_count_mask = -2; > @@ -648,16 +652,16 @@ void free_split_items_count(struct ht_items_count > *count) > } > > static > -void ht_count_add(struct cds_lfht *ht, unsigned long size) > +void ht_count_add(struct cds_lfht *ht, unsigned long size, unsigned long > hash) > { > } > > static > -void ht_count_del(struct cds_lfht *ht, unsigned long size) > +void ht_count_del(struct cds_lfht *ht, unsigned long size, unsigned long > hash) > { > } > > -#endif /* #else #if defined(HAVE_SCHED_GETCPU) && defined(HAVE_SYSCONF) */ > +#endif /* #else #if defined(HAVE_SYSCONF) */ > > > static > @@ -1504,7 +1508,7 @@ void cds_lfht_add(struct cds_lfht *ht, struct > cds_lfht_node *node) > > size = rcu_dereference(ht->t.size); > _cds_lfht_add(ht, size, node, NULL, 0); > - ht_count_add(ht, size); > + ht_count_add(ht, size, hash); > } > > struct cds_lfht_node *cds_lfht_add_unique(struct cds_lfht *ht, > @@ -1519,7 +1523,7 @@ struct cds_lfht_node *cds_lfht_add_unique(struct > cds_lfht *ht, > size = rcu_dereference(ht->t.size); > _cds_lfht_add(ht, size, node, &iter, 0); > if (iter.node == node) > - ht_count_add(ht, size); > + ht_count_add(ht, size, hash); > return iter.node; > } > > @@ -1536,7 +1540,7 @@ struct cds_lfht_node *cds_lfht_add_replace(struct > cds_lfht *ht, > for (;;) { > _cds_lfht_add(ht, size, node, &iter, 0); > if (iter.node == node) { > - ht_count_add(ht, size); > + ht_count_add(ht, size, hash); > return NULL; > } > > @@ -1557,13 +1561,15 @@ int cds_lfht_replace(struct cds_lfht *ht, struct > cds_lfht_iter *old_iter, > > int cds_lfht_del(struct cds_lfht *ht, struct cds_lfht_iter *iter) > { > - unsigned long size; > + unsigned long size, hash; > int ret; > > size = rcu_dereference(ht->t.size); > ret = _cds_lfht_del(ht, size, iter->node, 0); > - if (!ret) > - ht_count_del(ht, size); > + if (!ret) { > + hash = bit_reverse_ulong(iter->node->p.reverse_hash); > + ht_count_del(ht, size, hash); > + } > return ret; > } > > @@ -1809,7 +1815,7 @@ void cds_lfht_resize_lazy(struct cds_lfht *ht, unsigned > long size, int growth) > } > } > > -#if defined(HAVE_SCHED_GETCPU) && defined(HAVE_SYSCONF) > +#if defined(HAVE_SYSCONF) > > static > void cds_lfht_resize_lazy_count(struct cds_lfht *ht, unsigned long size, > -- > 1.7.4.4 > -- Mathieu Desnoyers Operating System Efficiency R&D Consultant EfficiOS Inc. http://www.efficios.com _______________________________________________ ltt-dev mailing list [email protected] http://lists.casi.polymtl.ca/cgi-bin/mailman/listinfo/ltt-dev
