[ltt-dev] [PATCH 04/10 round10] remove struct rcu_level

Mathieu Desnoyers mathieu.desnoyers at efficios.com
Tue Nov 22 05:08:25 EST 2011


* Lai Jiangshan (laijs at cn.fujitsu.com) wrote:
> Signed-off-by: Lai Jiangshan <laijs at cn.fujitsu.com>

This change looks fine. Please resubmit along with the other patches, as
they need to be applied before.

Acked-by: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>

> ---
>  rculfhash.c |   28 ++++++++++++----------------
>  1 files changed, 12 insertions(+), 16 deletions(-)
> 
> diff --git a/rculfhash.c b/rculfhash.c
> index a72e1a5..2df133c 100644
> --- a/rculfhash.c
> +++ b/rculfhash.c
> @@ -238,27 +238,23 @@ struct ht_items_count {
>  } __attribute__((aligned(CAA_CACHE_LINE_SIZE)));
>  
>  /*
> - * rcu_level: Contains the per order-index-level bucket node table. The
> - * size of each bucket node table is half the number of hashes contained
> - * in this order (except for order 0). The minimum allocation size
> - * parameter allows combining the bucket node arrays of the lowermost
> - * levels to improve cache locality for small index orders.
> - */
> -struct rcu_level {
> -	/* Note: manually update allocation length when adding a field */
> -	struct cds_lfht_node nodes[0];
> -};
> -
> -/*
>   * rcu_table: Contains the size and desired new size if a resize
>   * operation is in progress, as well as the statically-sized array of
> - * rcu_level pointers.
> + * bucket table pointers.
>   */
>  struct rcu_table {
>  	unsigned long size;	/* always a power of 2, shared (RCU) */
>  	unsigned long resize_target;
>  	int resize_initiated;
> -	struct rcu_level *tbl[MAX_TABLE_ORDER];
> +
> +	/*
> +	 * Contains the per order-index-level bucket node table. The size
> +	 * of each bucket node table is half the number of hashes contained
> +	 * in this order (except for order 0). The minimum allocation size
> +	 * parameter allows combining the bucket node arrays of the lowermost
> +	 * levels to improve cache locality for small index orders.
> +	 */
> +	struct cds_lfht_node *tbl[MAX_TABLE_ORDER];
>  };
>  
>  /*
> @@ -794,7 +790,7 @@ struct cds_lfht_node *bucket_at(struct cds_lfht *ht, unsigned long index)
>  	if ((__builtin_constant_p(index) && index == 0)
>  			|| index < ht->min_alloc_size) {
>  		dbg_printf("bucket index %lu order 0 aridx 0\n", index);
> -		return &ht->t.tbl[0]->nodes[index];
> +		return &ht->t.tbl[0][index];
>  	}
>  	/*
>  	 * equivalent to get_count_order_ulong(index + 1), but optimizes
> @@ -804,7 +800,7 @@ struct cds_lfht_node *bucket_at(struct cds_lfht *ht, unsigned long index)
>  	order = fls_ulong(index);
>  	dbg_printf("bucket index %lu order %lu aridx %lu\n",
>  		   index, order, index & ((1UL << (order - 1)) - 1));
> -	return &ht->t.tbl[order]->nodes[index & ((1UL << (order - 1)) - 1)];
> +	return &ht->t.tbl[order][index & ((1UL << (order - 1)) - 1)];
>  }
>  
>  static inline
> -- 
> 1.7.4.4
> 

-- 
Mathieu Desnoyers
Operating System Efficiency R&D Consultant
EfficiOS Inc.
http://www.efficios.com




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