[userspace-rcu.git] / rcuja / rcuja-range.c

/*
 * rcuja/rcuja-range.c
 *
 * Userspace RCU library - RCU Judy Array Range Support
 *
 * Copyright 2012-2013 - Mathieu Desnoyers <mathieu.desnoyers@efficios.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
 */

#define _LGPL_SOURCE
#include <stdint.h>
#include <errno.h>
#include <limits.h>
#include <string.h>
#include <assert.h>
#include <pthread.h>
#include <urcu/rcuja.h>
#include <urcu/compiler.h>
#include <urcu/arch.h>
#include <urcu-pointer.h>
#include <urcu/uatomic.h>
#include <urcu/rcuja-range.h>
#include <urcu-flavor.h>

#include "rcuja-internal.h"

/*
 * Discussion about order of lookup/lock vs allocated node deletion.
 *
 * - If node deletion returns before call to
 *   cds_ja_range_lookup(), the node will not be found by lookup.
 * - If node deletion is called after cds_ja_range_lock() returns a
 *   non-NULL range, the deletion will wait until the lock is released
 *   before it takes place.
 * - If node deletion call/return overlaps with the call to
 *   cds_ja_range_lookup() and return from cds_ja_range_lock(), the node
 *   may or may not be found by each of cds_ja_range_lookup() and
 *   cds_ja_range_lock().
 */

/*
 * Discussion about order of lookup/lock vs allocated node add. Assuming
 * no concurrent delete.
 *
 * - If node add returns before call to
 *   cds_ja_range_lookup(), the node will be found by lookup.
 * - If node add is called after cds_ja_range_lookup returns, the node
 *   will not be found by lookup.
 * - If node add call/return overlaps with the call to and return from
 *   cds_ja_range_lookup(), the node may or may not be found.
 * - If node add call/return overlaps with call to cds_ja_range_lookup()
 *   and return from cds_ja_range_lock(), in the specific case where
 *   cds_ja_range_lookup() _does_ succeed, then cds_ja_range_lock() will
 *   succeed (still assuming no concurrent deletion).
 */

/*
 * Discussion of the type state transitions.
 *
 * State transitions of "type" always go from either:
 *
 * CDS_JA_RANGE_FREE -> CDS_JA_RANGE_REMOVED
 * or
 * CDS_JA_RANGE_ALLOCATED -> CDS_JA_RANGE_REMOVED
 *
 * A range type never changes otherwise.
 */


struct cds_ja_range *cds_ja_range_lookup(struct cds_ja *ja, uint64_t key)
{
	struct cds_ja_node *node, *last_node;
	struct cds_ja_range *range;

	node = cds_ja_lookup_below_equal(ja, key, NULL);
	assert(node);
	/*
	 * Get the last of duplicate chain. Adding a node to Judy array
	 * duplicates inserts them at the end of the chain.
	 */
	cds_ja_for_each_duplicate_rcu(node)
		last_node = node;
	range = caa_container_of(last_node, struct cds_ja_range, ja_node);
	/*
	 * If last node in the duplicates is removed or free, we can
	 * consider that either a removal or add operation is in
	 * progress, or removal is the last completed operation to
	 * update this range. We can therefore consider that this area
	 * is not allocated.
	 */
	if (range->type != CDS_JA_RANGE_ALLOCATED)
		return NULL;
	/*
	 * We found an allocated range. We can return it for use with
	 * RCU read-side prototection for existence. However, we have no
	 * mutual exclusion against removal at this point.
	 */
	return range;
}

/*
 * Provide mutual exclusion against removal.
 */
struct cds_ja_range *cds_ja_range_lock(struct cds_ja_range *range)
{
	pthread_mutex_lock(&range->lock);

	if (range->type == CDS_JA_RANGE_REMOVED)
		goto removed;
	return range;

removed:
	pthread_mutex_unlock(&range->lock);
	return NULL;
}

void cds_ja_range_unlock(struct cds_ja_range *range)
{
	pthread_mutex_unlock(&range->lock);
}

static
struct cds_ja_range *range_create(
		uint64_t start,		/* inclusive */
		uint64_t end,		/* inclusive */
		enum cds_ja_range_type type)
{
	struct cds_ja_range *range;

	range = calloc(sizeof(*range), 1);
	if (!range)
		return NULL;
	range->start = start;
	range->end = end;
	range->type = type;
	pthread_mutex_init(&range->lock, NULL);
	return range;
}

static
void free_range_cb(struct rcu_head *head)
{
	struct cds_ja_range *range =
		caa_container_of(head, struct cds_ja_range, head);
	free(range);
}

static
void free_range(struct cds_ja_range *range)
{
	free(range);
}

static
void rcu_free_range(struct cds_ja *ja, struct cds_ja_range *range)
{
	cds_lfht_rcu_flavor(ja->ht)->update_call_rcu(&range->head,
			free_range_cb);
}

struct cds_ja_range *cds_ja_range_add(struct cds_ja *ja,
		uint64_t start,		/* inclusive */
		uint64_t end)		/* inclusive */
{
	struct cds_ja_node *old_node, *old_node_end;
	struct cds_ja_range *old_range, *old_range_end, *new_range, *ranges[3];
	unsigned int nr_ranges, i;
	int ret;

retry:
	/*
	 * Find if requested range is entirely contained within a single
	 * free range.
	 */
	old_node = cds_ja_lookup_below_equal(ja, start, NULL);
	assert(old_node);

	old_range = caa_container_of(old_node, struct cds_ja_range, ja_node);
	switch (CMM_LOAD_SHARED(old_range->type)) {
	case CDS_JA_RANGE_ALLOCATED:
		return NULL;
	case CDS_JA_RANGE_FREE:
		break;
	case CDS_JA_RANGE_REMOVED:
		goto retry;
	}

	old_node_end = cds_ja_lookup_below_equal(ja, end, NULL);
	assert(old_node_end);
	old_range_end = caa_container_of(old_node_end,
			struct cds_ja_range, ja_node);
	if (old_range_end != old_range) {
		switch (CMM_LOAD_SHARED(old_range->type)) {
		case CDS_JA_RANGE_ALLOCATED:
		case CDS_JA_RANGE_FREE:		/* fall-through */
			/*
			 * TODO: think about free range merge.
			 */
			return NULL;
		case CDS_JA_RANGE_REMOVED:
			goto retry;
		}
	}

	pthread_mutex_lock(&old_range->lock);

	if (old_range->type == CDS_JA_RANGE_REMOVED) {
		pthread_mutex_unlock(&old_range->lock);
		goto retry;
	}

	/* Create replacement ranges: at most 2 free and 1 allocated */
	if (start == old_range->start) {
		if (end == old_range->end) {
			/* 1 range */
			ranges[0] = new_range = range_create(start, end,
				CDS_JA_RANGE_ALLOCATED);
			nr_ranges = 1;
		} else {
			/* 2 ranges */
			ranges[0] = new_range = range_create(start, end,
				CDS_JA_RANGE_ALLOCATED);
			ranges[1] = range_create(end + 1, old_range->end,
				CDS_JA_RANGE_FREE);
			nr_ranges = 2;
		}
	} else {
		if (end == old_range->end) {
			/* 2 ranges */
			ranges[0] = range_create(old_range->start, start - 1,
				CDS_JA_RANGE_FREE);
			ranges[1] = new_range = range_create(start, end,
				CDS_JA_RANGE_ALLOCATED);
			nr_ranges = 2;
		} else {
			/* 3 ranges */
			ranges[0] = range_create(old_range->start, start - 1,
				CDS_JA_RANGE_FREE);
			ranges[1] = new_range = range_create(start, end,
				CDS_JA_RANGE_ALLOCATED);
			ranges[2] = range_create(end + 1, old_range->end,
				CDS_JA_RANGE_FREE);
			nr_ranges = 3;
		}
	}

	/* Add replacement ranges to Judy array */
	for (i = 0; i < nr_ranges; i++) {
		ret = cds_ja_add(ja, ranges[i]->start, &ranges[i]->ja_node);
		assert(!ret);
	}

	/*
	 * We add replacement ranges _before_ removing old ranges, so
	 * concurrent traversals will always see one or the other. This
	 * is OK because we temporarily have a duplicate key, and Judy
	 * arrays provide key existence guarantee for lookups performed
	 * concurrently with add followed by del of duplicate keys.
	 */

	/* Remove old free range */
	ret = cds_ja_del(ja, old_range->start, &old_range->ja_node);
	assert(!ret);
	old_range->type = CDS_JA_RANGE_REMOVED;
	pthread_mutex_unlock(&old_range->lock);

	rcu_free_range(ja, old_range);

	return new_range;
}

int cds_ja_range_del(struct cds_ja *ja, struct cds_ja_range *range)
{
	struct cds_ja_node *prev_node, *next_node;
	struct cds_ja_range *prev_range, *next_range, *new_range;
	struct cds_ja_range *merge_ranges[3];
	unsigned int nr_merge, i;
	uint64_t start, end;
	int ret;

retry:
	nr_merge = 0;
	prev_node = cds_ja_lookup_below_equal(ja, range->start - 1, NULL);
	prev_range = caa_container_of(prev_node, struct cds_ja_range, ja_node);
	if (prev_node && prev_range->type != CDS_JA_RANGE_ALLOCATED)
		merge_ranges[nr_merge++] = prev_range;

	merge_ranges[nr_merge++] = range;

	next_node = cds_ja_lookup_above_equal(ja, range->end + 1, NULL);
	next_range = caa_container_of(next_node, struct cds_ja_range, ja_node);
	if (next_node && next_range->type != CDS_JA_RANGE_ALLOCATED)
		merge_ranges[nr_merge++] = next_range;

	/* Acquire locks in increasing key order for range merge */
	for (i = 0; i < nr_merge; i++)
		pthread_mutex_lock(&merge_ranges[i]->lock);
	/* Ensure they are valid */
	for (i = 0; i < nr_merge; i++) {
		if (merge_ranges[i]->type == CDS_JA_RANGE_REMOVED)
			goto unlock_retry;
	}

	/* Create new free range */
	start = merge_ranges[0]->start;
	end = merge_ranges[nr_merge - 1]->end;
	new_range = range_create(start, end, CDS_JA_RANGE_FREE);
	ret = cds_ja_add(ja, start, &new_range->ja_node);
	assert(!ret);

	/* Remove old ranges */
	for (i = 0; i < nr_merge; i++) {
		ret = cds_ja_del(ja, merge_ranges[i]->start,
				&merge_ranges[i]->ja_node);
		assert(!ret);
		merge_ranges[i]->type = CDS_JA_RANGE_REMOVED;
		pthread_mutex_unlock(&merge_ranges[i]->lock);
		rcu_free_range(ja, merge_ranges[i]);
	}

	return 0;

	/* retry paths */
unlock_retry:
	for (i = 0; i < nr_merge; i++)
		pthread_mutex_unlock(&merge_ranges[i]->lock);
	goto retry;
}

int cds_ja_range_init(struct cds_ja *ja)
{
	struct cds_ja_node *node;
	struct cds_ja_range *range;
	int ret;

	/*
	 * Sanity check: should be empty.
	 */
	node = cds_ja_lookup_above_equal(ja, 0, NULL);
	if (node)
		return -EINVAL;
	range = range_create(0, UINT64_MAX, CDS_JA_RANGE_FREE);
	if (!range)
		return -EINVAL;
	ret = cds_ja_add(ja, 0, &range->ja_node);
	return ret;
}

int cds_ja_range_fini(struct cds_ja *ja)
{
	uint64_t key;
	struct cds_ja_node *ja_node;
	int ret = 0;

	cds_ja_for_each_key_rcu(ja, key, ja_node) {
		struct cds_ja_node *tmp_node;

		cds_ja_for_each_duplicate_safe_rcu(ja_node, tmp_node) {
			struct cds_ja_range *range;

			range = caa_container_of(ja_node,
					struct cds_ja_range, ja_node);
			ret = cds_ja_del(ja, key, &range->ja_node);
			if (ret) {
				goto end;
			}
			/* Alone using Judy array, OK to free now */
			free_range(range);
		}
	}
end:
	return ret;
}
Commit	Line	Data
b45a45b9 MD	1	/*
	2	* rcuja/rcuja-range.c
	3	*
	4	* Userspace RCU library - RCU Judy Array Range Support
	5	*
	6	* Copyright 2012-2013 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	7	*
	8	* This library is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU Lesser General Public
	10	* License as published by the Free Software Foundation; either
	11	* version 2.1 of the License, or (at your option) any later version.
	12	*
	13	* This library is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	16	* Lesser General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU Lesser General Public
	19	* License along with this library; if not, write to the Free Software
	20	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	21	*/
	22
	23	#define _LGPL_SOURCE
	24	#include <stdint.h>
	25	#include <errno.h>
	26	#include <limits.h>
	27	#include <string.h>
	28	#include <assert.h>
	29	#include <pthread.h>
	30	#include <urcu/rcuja.h>
	31	#include <urcu/compiler.h>
	32	#include <urcu/arch.h>
	33	#include <urcu-pointer.h>
	34	#include <urcu/uatomic.h>
	35	#include <urcu/rcuja-range.h>
	36	#include <urcu-flavor.h>
	37
	38	#include "rcuja-internal.h"
	39
	40	/*
	41	* Discussion about order of lookup/lock vs allocated node deletion.
	42	*
	43	* - If node deletion returns before call to
	44	* cds_ja_range_lookup(), the node will not be found by lookup.
	45	* - If node deletion is called after cds_ja_range_lock() returns a
	46	* non-NULL range, the deletion will wait until the lock is released
	47	* before it takes place.
	48	* - If node deletion call/return overlaps with the call to
	49	* cds_ja_range_lookup() and return from cds_ja_range_lock(), the node
	50	* may or may not be found by each of cds_ja_range_lookup() and
	51	* cds_ja_range_lock().
	52	*/
	53
	54	/*
	55	* Discussion about order of lookup/lock vs allocated node add. Assuming
	56	* no concurrent delete.
	57	*
	58	* - If node add returns before call to
	59	* cds_ja_range_lookup(), the node will be found by lookup.
	60	* - If node add is called after cds_ja_range_lookup returns, the node
	61	* will not be found by lookup.
	62	* - If node add call/return overlaps with the call to and return from
	63	* cds_ja_range_lookup(), the node may or may not be found.
	64	* - If node add call/return overlaps with call to cds_ja_range_lookup()
65	* and return from cds_ja_range_lock(), in the specific case where
66	* cds_ja_range_lookup() _does_ succeed, then cds_ja_range_lock() will
67	* succeed (still assuming no concurrent deletion).
68	*/
69
70	/*
71	* Discussion of the type state transitions.
72	*
73	* State transitions of "type" always go from either:
74	*
75	* CDS_JA_RANGE_FREE -> CDS_JA_RANGE_REMOVED
76	* or
77	* CDS_JA_RANGE_ALLOCATED -> CDS_JA_RANGE_REMOVED
78	*
79	* A range type never changes otherwise.
80	*/
81
82
83	struct cds_ja_range cds_ja_range_lookup(struct cds_ja ja, uint64_t key)
84	{
85	struct cds_ja_node node, last_node;
86	struct cds_ja_range *range;
87
88	node = cds_ja_lookup_below_equal(ja, key, NULL);
89	assert(node);
90	/*
91	* Get the last of duplicate chain. Adding a node to Judy array
92	* duplicates inserts them at the end of the chain.
93	*/
94	cds_ja_for_each_duplicate_rcu(node)
95	last_node = node;
96	range = caa_container_of(last_node, struct cds_ja_range, ja_node);
97	/*
98	* If last node in the duplicates is removed or free, we can
99	* consider that either a removal or add operation is in
100	* progress, or removal is the last completed operation to
101	* update this range. We can therefore consider that this area
102	* is not allocated.
103	*/
104	if (range->type != CDS_JA_RANGE_ALLOCATED)
105	return NULL;
106	/*
107	* We found an allocated range. We can return it for use with
108	* RCU read-side prototection for existence. However, we have no
109	* mutual exclusion against removal at this point.
110	*/
111	return range;
112	}
113
114	/*
115	* Provide mutual exclusion against removal.
116	*/
117	struct cds_ja_range cds_ja_range_lock(struct cds_ja_range range)
118	{
119	pthread_mutex_lock(&range->lock);
120
121	if (range->type == CDS_JA_RANGE_REMOVED)
122	goto removed;
123	return range;
124
125	removed:
126	pthread_mutex_unlock(&range->lock);
127	return NULL;
128	}
129
130	void cds_ja_range_unlock(struct cds_ja_range *range)
131	{
132	pthread_mutex_unlock(&range->lock);
133	}
134
135	static
136	struct cds_ja_range *range_create(
137	uint64_t start, /* inclusive */
138	uint64_t end, /* inclusive */
139	enum cds_ja_range_type type)
140	{
141	struct cds_ja_range *range;
142
143	range = calloc(sizeof(*range), 1);
144	if (!range)
145	return NULL;
146	range->start = start;
147	range->end = end;
148	range->type = type;
149	pthread_mutex_init(&range->lock, NULL);
150	return range;
151	}
152
153	static
154	void free_range_cb(struct rcu_head *head)
155	{
156	struct cds_ja_range *range =
157	caa_container_of(head, struct cds_ja_range, head);
158	free(range);
159	}
160
161	static
162	void free_range(struct cds_ja_range *range)
163	{
164	free(range);
165	}
166
167	static
168	void rcu_free_range(struct cds_ja ja, struct cds_ja_range range)
169	{
170	cds_lfht_rcu_flavor(ja->ht)->update_call_rcu(&range->head,
171	free_range_cb);
172	}
173
174	struct cds_ja_range cds_ja_range_add(struct cds_ja ja,
175	uint64_t start, /* inclusive */
176	uint64_t end) /* inclusive */
177	{
178	struct cds_ja_node old_node, old_node_end;
179	struct cds_ja_range old_range, old_range_end, new_range, ranges[3];
180	unsigned int nr_ranges, i;
181	int ret;
182
183	retry:
184	/*
185	* Find if requested range is entirely contained within a single
186	* free range.
187	*/
188	old_node = cds_ja_lookup_below_equal(ja, start, NULL);
189	assert(old_node);
190
191	old_range = caa_container_of(old_node, struct cds_ja_range, ja_node);
192	switch (CMM_LOAD_SHARED(old_range->type)) {
193	case CDS_JA_RANGE_ALLOCATED:
194	return NULL;
195	case CDS_JA_RANGE_FREE:
196	break;
197	case CDS_JA_RANGE_REMOVED:
198	goto retry;
199	}
200
201	old_node_end = cds_ja_lookup_below_equal(ja, end, NULL);
202	assert(old_node_end);
203	old_range_end = caa_container_of(old_node_end,
204	struct cds_ja_range, ja_node);
205	if (old_range_end != old_range) {
206	switch (CMM_LOAD_SHARED(old_range->type)) {
207	case CDS_JA_RANGE_ALLOCATED:
208	case CDS_JA_RANGE_FREE: /* fall-through */
209	/*
210	* TODO: think about free range merge.
211	*/
212	return NULL;
213	case CDS_JA_RANGE_REMOVED:
214	goto retry;
215	}
216	}
217
218	pthread_mutex_lock(&old_range->lock);
219
220	if (old_range->type == CDS_JA_RANGE_REMOVED) {
221	pthread_mutex_unlock(&old_range->lock);
222	goto retry;
223	}
224
225	/* Create replacement ranges: at most 2 free and 1 allocated */
226	if (start == old_range->start) {
227	if (end == old_range->end) {
228	/* 1 range */
229	ranges[0] = new_range = range_create(start, end,
230	CDS_JA_RANGE_ALLOCATED);
231	nr_ranges = 1;
232	} else {
233	/* 2 ranges */
234	ranges[0] = new_range = range_create(start, end,
235	CDS_JA_RANGE_ALLOCATED);
236	ranges[1] = range_create(end + 1, old_range->end,
237	CDS_JA_RANGE_FREE);
238	nr_ranges = 2;
239	}
240	} else {
241	if (end == old_range->end) {
242	/* 2 ranges */
243	ranges[0] = range_create(old_range->start, start - 1,
244	CDS_JA_RANGE_FREE);
245	ranges[1] = new_range = range_create(start, end,
246	CDS_JA_RANGE_ALLOCATED);
247	nr_ranges = 2;
248	} else {
249	/* 3 ranges */
250	ranges[0] = range_create(old_range->start, start - 1,
251	CDS_JA_RANGE_FREE);
252	ranges[1] = new_range = range_create(start, end,
253	CDS_JA_RANGE_ALLOCATED);
254	ranges[2] = range_create(end + 1, old_range->end,
255	CDS_JA_RANGE_FREE);
256	nr_ranges = 3;
257	}
258	}
259
260	/* Add replacement ranges to Judy array */
261	for (i = 0; i < nr_ranges; i++) {
262	ret = cds_ja_add(ja, ranges[i]->start, &ranges[i]->ja_node);
263	assert(!ret);
264	}
265
266	/*
267	* We add replacement ranges _before_ removing old ranges, so
268	* concurrent traversals will always see one or the other. This
269	* is OK because we temporarily have a duplicate key, and Judy
270	* arrays provide key existence guarantee for lookups performed
271	* concurrently with add followed by del of duplicate keys.
272	*/
273
274	/* Remove old free range */
275	ret = cds_ja_del(ja, old_range->start, &old_range->ja_node);
276	assert(!ret);
277	old_range->type = CDS_JA_RANGE_REMOVED;
278	pthread_mutex_unlock(&old_range->lock);
279
280	rcu_free_range(ja, old_range);
281
282	return new_range;
283	}
284
285	int cds_ja_range_del(struct cds_ja ja, struct cds_ja_range range)
286	{
287	struct cds_ja_node prev_node, next_node;
288	struct cds_ja_range prev_range, next_range, *new_range;
289	struct cds_ja_range *merge_ranges[3];
290	unsigned int nr_merge, i;
291	uint64_t start, end;
292	int ret;
293
294	retry:
295	nr_merge = 0;
296	prev_node = cds_ja_lookup_below_equal(ja, range->start - 1, NULL);
297	prev_range = caa_container_of(prev_node, struct cds_ja_range, ja_node);
298	if (prev_node && prev_range->type != CDS_JA_RANGE_ALLOCATED)
299	merge_ranges[nr_merge++] = prev_range;
300
301	merge_ranges[nr_merge++] = range;
302
303	next_node = cds_ja_lookup_above_equal(ja, range->end + 1, NULL);
304	next_range = caa_container_of(next_node, struct cds_ja_range, ja_node);
305	if (next_node && next_range->type != CDS_JA_RANGE_ALLOCATED)
306	merge_ranges[nr_merge++] = next_range;
307
308	/* Acquire locks in increasing key order for range merge */
309	for (i = 0; i < nr_merge; i++)
310	pthread_mutex_lock(&merge_ranges[i]->lock);
311	/* Ensure they are valid */
312	for (i = 0; i < nr_merge; i++) {
313	if (merge_ranges[i]->type == CDS_JA_RANGE_REMOVED)
314	goto unlock_retry;
315	}
316
317	/* Create new free range */
318	start = merge_ranges[0]->start;
319	end = merge_ranges[nr_merge - 1]->end;
320	new_range = range_create(start, end, CDS_JA_RANGE_FREE);
321	ret = cds_ja_add(ja, start, &new_range->ja_node);
322	assert(!ret);
323
324	/* Remove old ranges */
325	for (i = 0; i < nr_merge; i++) {
326	ret = cds_ja_del(ja, merge_ranges[i]->start,
327	&merge_ranges[i]->ja_node);
328	assert(!ret);
329	merge_ranges[i]->type = CDS_JA_RANGE_REMOVED;
330	pthread_mutex_unlock(&merge_ranges[i]->lock);
331	rcu_free_range(ja, merge_ranges[i]);
332	}
333
334	return 0;
335
336	/* retry paths */
337	unlock_retry:
338	for (i = 0; i < nr_merge; i++)
339	pthread_mutex_unlock(&merge_ranges[i]->lock);
340	goto retry;
341	}
342
343	int cds_ja_range_init(struct cds_ja *ja)
344	{
345	struct cds_ja_node *node;
346	struct cds_ja_range *range;
347	int ret;
348
349	/*
350	* Sanity check: should be empty.
351	*/
352	node = cds_ja_lookup_above_equal(ja, 0, NULL);
353	if (node)
354	return -EINVAL;
355	range = range_create(0, UINT64_MAX, CDS_JA_RANGE_FREE);
356	if (!range)
357	return -EINVAL;
358	ret = cds_ja_add(ja, 0, &range->ja_node);
359	return ret;
360	}
361
362	int cds_ja_range_fini(struct cds_ja *ja)
363	{
364	uint64_t key;
365	struct cds_ja_node *ja_node;
366	int ret = 0;
367
368	cds_ja_for_each_key_rcu(ja, key, ja_node) {
369	struct cds_ja_node *tmp_node;
370
371	cds_ja_for_each_duplicate_safe_rcu(ja_node, tmp_node) {
372	struct cds_ja_range *range;
373
374	range = caa_container_of(ja_node,
375	struct cds_ja_range, ja_node);
376	ret = cds_ja_del(ja, key, &range->ja_node);
377	if (ret) {
378	goto end;
379	}
380	/* Alone using Judy array, OK to free now */
381	free_range(range);
382	}
383	}
384	end:
385	return ret;
386	}