X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=liblttng-ht%2Frculfhash-mm-chunk.c;fp=liblttng-ht%2Frculfhash-mm-chunk.c;h=7204831e5b12d61794b8ed5514060cf7b47b56ae;hp=0000000000000000000000000000000000000000;hb=bec399405a4667411ae06bbbcbed678e42e93a30;hpb=67cea2c94b841ee9b38ba80ab8a9eafff5f76408

diff --git a/liblttng-ht/rculfhash-mm-chunk.c b/liblttng-ht/rculfhash-mm-chunk.c
new file mode 100644
index 000000000..7204831e5
--- /dev/null
+++ b/liblttng-ht/rculfhash-mm-chunk.c
@@ -0,0 +1,97 @@
+/*
+ * rculfhash-mm-chunk.c
+ *
+ * Chunk based memory management for Lock-Free RCU Hash Table
+ *
+ * Copyright 2011 - Lai Jiangshan <laijs@cn.fujitsu.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stddef.h>
+#include "rculfhash-internal.h"
+
+static
+void cds_lfht_alloc_bucket_table(struct cds_lfht *ht, unsigned long order)
+{
+	if (order == 0) {
+		ht->tbl_chunk[0] = calloc(ht->min_nr_alloc_buckets,
+			sizeof(struct cds_lfht_node));
+		assert(ht->tbl_chunk[0]);
+	} else if (order > ht->min_alloc_buckets_order) {
+		unsigned long i, len = 1UL << (order - 1 - ht->min_alloc_buckets_order);
+
+		for (i = len; i < 2 * len; i++) {
+			ht->tbl_chunk[i] = calloc(ht->min_nr_alloc_buckets,
+				sizeof(struct cds_lfht_node));
+			assert(ht->tbl_chunk[i]);
+		}
+	}
+	/* Nothing to do for 0 < order && order <= ht->min_alloc_buckets_order */
+}
+
+/*
+ * cds_lfht_free_bucket_table() should be called with decreasing order.
+ * When cds_lfht_free_bucket_table(0) is called, it means the whole
+ * lfht is destroyed.
+ */
+static
+void cds_lfht_free_bucket_table(struct cds_lfht *ht, unsigned long order)
+{
+	if (order == 0)
+		poison_free(ht->tbl_chunk[0]);
+	else if (order > ht->min_alloc_buckets_order) {
+		unsigned long i, len = 1UL << (order - 1 - ht->min_alloc_buckets_order);
+
+		for (i = len; i < 2 * len; i++)
+			poison_free(ht->tbl_chunk[i]);
+	}
+	/* Nothing to do for 0 < order && order <= ht->min_alloc_buckets_order */
+}
+
+static
+struct cds_lfht_node *bucket_at(struct cds_lfht *ht, unsigned long index)
+{
+	unsigned long chunk, offset;
+
+	chunk = index >> ht->min_alloc_buckets_order;
+	offset = index & (ht->min_nr_alloc_buckets - 1);
+	return &ht->tbl_chunk[chunk][offset];
+}
+
+static
+struct cds_lfht *alloc_cds_lfht(unsigned long min_nr_alloc_buckets,
+		unsigned long max_nr_buckets)
+{
+	unsigned long nr_chunks, cds_lfht_size;
+
+	min_nr_alloc_buckets = max(min_nr_alloc_buckets,
+				max_nr_buckets / MAX_CHUNK_TABLE);
+	nr_chunks = max_nr_buckets / min_nr_alloc_buckets;
+	cds_lfht_size = offsetof(struct cds_lfht, tbl_chunk) +
+			sizeof(struct cds_lfht_node *) * nr_chunks;
+	cds_lfht_size = max(cds_lfht_size, sizeof(struct cds_lfht));
+
+	return __default_alloc_cds_lfht(
+			&cds_lfht_mm_chunk, cds_lfht_size,
+			min_nr_alloc_buckets, max_nr_buckets);
+}
+
+const struct cds_lfht_mm_type cds_lfht_mm_chunk = {
+	.alloc_cds_lfht = alloc_cds_lfht,
+	.alloc_bucket_table = cds_lfht_alloc_bucket_table,
+	.free_bucket_table = cds_lfht_free_bucket_table,
+	.bucket_at = bucket_at,
+};