On 11/22/2011 06:06 PM, Mathieu Desnoyers wrote: > * Lai Jiangshan ([email protected]) wrote: >> Thanks to the wrappers of bucket table alloc/free. > > Sorry, I don't understand this change, and I don't see how the patch > below matches the patch title. This patch does not touch ht->t.size at > all, and seems to use MIN_TABLE_SIZE to replace ht->min_table_size, but > does not explain why this is possible. >
Original code always ensure ht->t.size >= ht->min_table_size. It is not good, ht->min_table_size should be used for allocation, not for the bucket size in used. Thanks, Lai Add: Original code don't do special alloc/free when ht->t.size < ht->min_table_size in init_table()/fini_table(), so we have to force ht->t.size >= ht->min_table_size. New code use the wrappers, they handle the special cases. > More below, > >> >> Signed-off-by: Lai Jiangshan <[email protected]> >> --- >> rculfhash.c | 19 ++++++++++--------- >> tests/test_urcu_hash.c | 2 +- >> 2 files changed, 11 insertions(+), 10 deletions(-) >> >> diff --git a/rculfhash.c b/rculfhash.c >> index c7f993f..a72e1a5 100644 >> --- a/rculfhash.c >> +++ b/rculfhash.c >> @@ -186,7 +186,8 @@ >> /* >> * Define the minimum table size. >> */ >> -#define MIN_TABLE_SIZE 1 >> +#define MIN_TABLE_ORDER 0 >> +#define MIN_TABLE_SIZE (1UL << MIN_TABLE_ORDER) >> >> #if (CAA_BITS_PER_LONG == 32) >> #define MAX_TABLE_ORDER 32 >> @@ -1141,7 +1142,7 @@ void init_table_populate_partition(struct cds_lfht >> *ht, unsigned long i, >> { >> unsigned long j, size = 1UL << (i - 1); >> >> - assert(i > ht->min_alloc_order); >> + assert(i > MIN_TABLE_ORDER); > > Here, all this does is change the min_alloc_order > >> ht->cds_lfht_rcu_read_lock(); >> for (j = start + size; j < size + start + len; j++) { >> struct cds_lfht_node *new_node = bucket_at(ht, j); >> @@ -1177,7 +1178,7 @@ void init_table(struct cds_lfht *ht, >> >> dbg_printf("init table: first_order %lu last_order %lu\n", >> first_order, last_order); >> - assert(first_order > ht->min_alloc_order); >> + assert(first_order > MIN_TABLE_ORDER); >> for (i = first_order; i <= last_order; i++) { >> unsigned long len; >> >> @@ -1239,7 +1240,7 @@ void remove_table_partition(struct cds_lfht *ht, >> unsigned long i, >> { >> unsigned long j, size = 1UL << (i - 1); >> >> - assert(i > ht->min_alloc_order); >> + assert(i > MIN_TABLE_ORDER); >> ht->cds_lfht_rcu_read_lock(); >> for (j = size + start; j < size + start + len; j++) { >> struct cds_lfht_node *fini_node = bucket_at(ht, j); >> @@ -1276,7 +1277,7 @@ void fini_table(struct cds_lfht *ht, >> >> dbg_printf("fini table: first_order %lu last_order %lu\n", >> first_order, last_order); >> - assert(first_order > ht->min_alloc_order); >> + assert(first_order > MIN_TABLE_ORDER); >> for (i = last_order; i >= first_order; i--) { >> unsigned long len; >> >> @@ -1376,7 +1377,7 @@ struct cds_lfht *_cds_lfht_new(unsigned long init_size, >> if (!init_size || (init_size & (init_size - 1))) >> return NULL; >> min_alloc_size = max(min_alloc_size, MIN_TABLE_SIZE); >> - init_size = max(init_size, min_alloc_size); >> + init_size = max(init_size, MIN_TABLE_SIZE); >> ht = calloc(1, sizeof(struct cds_lfht)); >> assert(ht); >> ht->flags = flags; >> @@ -1706,7 +1707,7 @@ void _do_cds_lfht_shrink(struct cds_lfht *ht, >> { >> unsigned long old_order, new_order; >> >> - new_size = max(new_size, ht->min_alloc_size); >> + new_size = max(new_size, MIN_TABLE_SIZE); >> old_order = get_count_order_ulong(old_size); >> new_order = get_count_order_ulong(new_size); >> dbg_printf("resize from %lu (order %lu) to %lu (order %lu) buckets\n", >> @@ -1754,7 +1755,7 @@ static >> void resize_target_update_count(struct cds_lfht *ht, >> unsigned long count) >> { >> - count = max(count, ht->min_alloc_size); >> + count = max(count, MIN_TABLE_SIZE); >> uatomic_set(&ht->t.resize_target, count); >> } >> >> @@ -1829,7 +1830,7 @@ void cds_lfht_resize_lazy_count(struct cds_lfht *ht, >> unsigned long size, >> { >> if (!(ht->flags & CDS_LFHT_AUTO_RESIZE)) >> return; >> - count = max(count, ht->min_alloc_size); >> + count = max(count, MIN_TABLE_SIZE); >> if (count == size) >> return; /* Already the right size, no resize needed */ >> if (count > size) { /* lazy grow */ >> diff --git a/tests/test_urcu_hash.c b/tests/test_urcu_hash.c >> index 509767c..b9e3e81 100644 >> --- a/tests/test_urcu_hash.c >> +++ b/tests/test_urcu_hash.c >> @@ -896,7 +896,7 @@ int main(int argc, char **argv) >> return -1; >> } >> >> - if (min_hash_alloc_size && min_hash_alloc_size * (min_hash_alloc_size - >> 1)) { >> + if (min_hash_alloc_size && min_hash_alloc_size & (min_hash_alloc_size - >> 1)) { > > This seems to fix a bug in the test program, but it's not documented. > Maybe this should go in as a separate patch ? > > Thanks, > > Mathieu > >> printf("Error: Min hash alloc size %lu is not a power of 2.\n", >> min_hash_alloc_size); >> return -1; >> -- >> 1.7.4.4 >> > _______________________________________________ ltt-dev mailing list [email protected] http://lists.casi.polymtl.ca/cgi-bin/mailman/listinfo/ltt-dev
