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android / kernel / common / e8e652b8c81afc06e9bc801f6eb4896516be2d62 / . / net / unix / garbage.c
blob: 67b2c3bfa113425273a9542827997c7cd091f295 [file] [log] [blame]
Thomas Gleixnera85036f2019-05-20 09:19:03 +0200[diff] [blame]1// SPDX-License-Identifier: GPL-2.0-or-later
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]2/*
3 * NET3: Garbage Collector For AF_UNIX sockets
4 *
5 * Garbage Collector:
6 * Copyright (C) Barak A. Pearlmutter.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]7 *
8 * Chopped about by Alan Cox 22/3/96 to make it fit the AF_UNIX socket problem.
9 * If it doesn't work blame me, it worked when Barak sent it.
10 *
11 * Assumptions:
12 *
13 * - object w/ a bit
14 * - free list
15 *
16 * Current optimizations:
17 *
18 * - explicit stack instead of recursion
19 * - tail recurse on first born instead of immediate push/pop
20 * - we gather the stuff that should not be killed into tree
21 * and stack is just a path from root to the current pointer.
22 *
23 * Future optimizations:
24 *
25 * - don't just push entire root set; process in place
26 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]27 * Fixes:
28 * Alan Cox 07 Sept 1997 Vmalloc internal stack as needed.
29 * Cope with changing max_files.
30 * Al Viro 11 Oct 1998
31 * Graph may have cycles. That is, we can send the descriptor
32 * of foo to bar and vice versa. Current code chokes on that.
33 * Fix: move SCM_RIGHTS ones into the separate list and then
34 * skb_free() them all instead of doing explicit fput's.
35 * Another problem: since fput() may block somebody may
36 * create a new unix_socket when we are in the middle of sweep
37 * phase. Fix: revert the logic wrt MARKED. Mark everything
38 * upon the beginning and unmark non-junk ones.
39 *
40 * [12 Oct 1998] AAARGH! New code purges all SCM_RIGHTS
41 * sent to connect()'ed but still not accept()'ed sockets.
42 * Fixed. Old code had slightly different problem here:
43 * extra fput() in situation when we passed the descriptor via
44 * such socket and closed it (descriptor). That would happen on
45 * each unix_gc() until the accept(). Since the struct file in
46 * question would go to the free list and might be reused...
47 * That might be the reason of random oopses on filp_close()
48 * in unrelated processes.
49 *
50 * AV 28 Feb 1999
51 * Kill the explicit allocation of stack. Now we keep the tree
52 * with root in dummy + pointer (gc_current) to one of the nodes.
53 * Stack is represented as path from gc_current to dummy. Unmark
54 * now means "add to tree". Push == "make it a son of gc_current".
55 * Pop == "move gc_current to parent". We keep only pointers to
56 * parents (->gc_tree).
57 * AV 1 Mar 1999
58 * Damn. Added missing check for ->dead in listen queues scanning.
59 *
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]60 * Miklos Szeredi 25 Jun 2007
61 * Reimplement with a cycle collecting algorithm. This should
62 * solve several problems with the previous code, like being racy
63 * wrt receive and holding up unrelated socket operations.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]64 */
YOSHIFUJI Hideakiac7bfa62007-02-09 23:25:23 +0900[diff] [blame]65
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]66#include <linux/kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]67#include <linux/string.h>
68#include <linux/socket.h>
69#include <linux/un.h>
70#include <linux/net.h>
71#include <linux/fs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]72#include <linux/skbuff.h>
73#include <linux/netdevice.h>
74#include <linux/file.h>
75#include <linux/proc_fs.h>
Arjan van de Ven4a3e2f72006-03-20 22:33:17 -0800[diff] [blame]76#include <linux/mutex.h>
dann frazier5f23b732008-11-26 15:32:27 -0800[diff] [blame]77#include <linux/wait.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]78
79#include <net/sock.h>
80#include <net/af_unix.h>
81#include <net/scm.h>
Arnaldo Carvalho de Meloc752f072005-08-09 20:08:28 -0700[diff] [blame]82#include <net/tcp_states.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]83
Jens Axboef4e65872019-02-08 09:01:44 -0700[diff] [blame]84#include "scm.h"
85
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]86/* Internal data structures and random procedures: */
87
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]88static LIST_HEAD(gc_candidates);
dann frazier5f23b732008-11-26 15:32:27 -0800[diff] [blame]89static DECLARE_WAIT_QUEUE_HEAD(unix_gc_wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]90
Pavel Emelyanov5c80f1a2007-11-10 22:07:13 -0800[diff] [blame]91static void scan_inflight(struct sock *x, void (*func)(struct unix_sock *),
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]92 struct sk_buff_head *hitlist)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]93{
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]94 struct sk_buff *skb;
95 struct sk_buff *next;
96
97 spin_lock(&x->sk_receive_queue.lock);
Ilpo Järvinena2f3be12010-05-03 03:22:18 +0000[diff] [blame]98 skb_queue_walk_safe(&x->sk_receive_queue, skb, next) {
Jason Eastmand1ab39f2015-04-22 00:56:42 -0600[diff] [blame]99 /* Do we have file descriptors ? */
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]100 if (UNIXCB(skb).fp) {
101 bool hit = false;
Jason Eastmand1ab39f2015-04-22 00:56:42 -0600[diff] [blame]102 /* Process the descriptors of this socket */
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]103 int nfd = UNIXCB(skb).fp->count;
104 struct file **fp = UNIXCB(skb).fp->fp;
Jason Eastmand1ab39f2015-04-22 00:56:42 -0600[diff] [blame]105
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]106 while (nfd--) {
Jason Eastmand1ab39f2015-04-22 00:56:42 -0600[diff] [blame]107 /* Get the socket the fd matches if it indeed does so */
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]108 struct sock *sk = unix_get_socket(*fp++);
Jason Eastmand1ab39f2015-04-22 00:56:42 -0600[diff] [blame]109
Pavel Emelyanov5c80f1a2007-11-10 22:07:13 -0800[diff] [blame]110 if (sk) {
Miklos Szeredi62093442008-11-09 15:23:57 +0100[diff] [blame]111 struct unix_sock *u = unix_sk(sk);
112
Jason Eastmand1ab39f2015-04-22 00:56:42 -0600[diff] [blame]113 /* Ignore non-candidates, they could
Miklos Szeredi62093442008-11-09 15:23:57 +0100[diff] [blame]114 * have been added to the queues after
115 * starting the garbage collection
116 */
Eric Dumazet60bc8512013-05-01 05:24:03 +0000[diff] [blame]117 if (test_bit(UNIX_GC_CANDIDATE, &u->gc_flags)) {
Miklos Szeredi62093442008-11-09 15:23:57 +0100[diff] [blame]118 hit = true;
Jason Eastmand1ab39f2015-04-22 00:56:42 -0600[diff] [blame]119
Miklos Szeredi62093442008-11-09 15:23:57 +0100[diff] [blame]120 func(u);
121 }
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]122 }
123 }
124 if (hit && hitlist != NULL) {
125 __skb_unlink(skb, &x->sk_receive_queue);
126 __skb_queue_tail(hitlist, skb);
127 }
128 }
129 }
130 spin_unlock(&x->sk_receive_queue.lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]131}
132
Pavel Emelyanov5c80f1a2007-11-10 22:07:13 -0800[diff] [blame]133static void scan_children(struct sock *x, void (*func)(struct unix_sock *),
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]134 struct sk_buff_head *hitlist)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]135{
Jason Eastmand1ab39f2015-04-22 00:56:42 -0600[diff] [blame]136 if (x->sk_state != TCP_LISTEN) {
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]137 scan_inflight(x, func, hitlist);
Jason Eastmand1ab39f2015-04-22 00:56:42 -0600[diff] [blame]138 } else {
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]139 struct sk_buff *skb;
140 struct sk_buff *next;
141 struct unix_sock *u;
142 LIST_HEAD(embryos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]143
Jason Eastmand1ab39f2015-04-22 00:56:42 -0600[diff] [blame]144 /* For a listening socket collect the queued embryos
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]145 * and perform a scan on them as well.
146 */
147 spin_lock(&x->sk_receive_queue.lock);
Ilpo Järvinena2f3be12010-05-03 03:22:18 +0000[diff] [blame]148 skb_queue_walk_safe(&x->sk_receive_queue, skb, next) {
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]149 u = unix_sk(skb->sk);
150
Jason Eastmand1ab39f2015-04-22 00:56:42 -0600[diff] [blame]151 /* An embryo cannot be in-flight, so it's safe
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]152 * to use the list link.
153 */
154 BUG_ON(!list_empty(&u->link));
155 list_add_tail(&u->link, &embryos);
156 }
157 spin_unlock(&x->sk_receive_queue.lock);
158
159 while (!list_empty(&embryos)) {
160 u = list_entry(embryos.next, struct unix_sock, link);
161 scan_inflight(&u->sk, func, hitlist);
162 list_del_init(&u->link);
163 }
164 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]165}
166
Pavel Emelyanov5c80f1a2007-11-10 22:07:13 -0800[diff] [blame]167static void dec_inflight(struct unix_sock *usk)
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]168{
Kuniyuki Iwashima65e0a922024-01-23 09:08:53 -0800[diff] [blame]169 usk->inflight--;
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]170}
171
Pavel Emelyanov5c80f1a2007-11-10 22:07:13 -0800[diff] [blame]172static void inc_inflight(struct unix_sock *usk)
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]173{
Kuniyuki Iwashima65e0a922024-01-23 09:08:53 -0800[diff] [blame]174 usk->inflight++;
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]175}
176
Pavel Emelyanov5c80f1a2007-11-10 22:07:13 -0800[diff] [blame]177static void inc_inflight_move_tail(struct unix_sock *u)
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]178{
Kuniyuki Iwashima65e0a922024-01-23 09:08:53 -0800[diff] [blame]179 u->inflight++;
180
Jason Eastmand1ab39f2015-04-22 00:56:42 -0600[diff] [blame]181 /* If this still might be part of a cycle, move it to the end
Miklos Szeredi62093442008-11-09 15:23:57 +0100[diff] [blame]182 * of the list, so that it's checked even if it was already
183 * passed over
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]184 */
Eric Dumazet60bc8512013-05-01 05:24:03 +0000[diff] [blame]185 if (test_bit(UNIX_GC_MAYBE_CYCLE, &u->gc_flags))
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]186 list_move_tail(&u->link, &gc_candidates);
187}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]188
Fabian Frederick505e9072014-10-07 23:02:15 +0200[diff] [blame]189static bool gc_in_progress;
Eric Dumazet99156722010-11-24 09:15:27 -0800[diff] [blame]190#define UNIX_INFLIGHT_TRIGGER_GC 16000
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]191
dann frazier5f23b732008-11-26 15:32:27 -0800[diff] [blame]192void wait_for_unix_gc(void)
193{
Jason Eastmand1ab39f2015-04-22 00:56:42 -0600[diff] [blame]194 /* If number of inflight sockets is insane,
Eric Dumazet99156722010-11-24 09:15:27 -0800[diff] [blame]195 * force a garbage collect right now.
Eric Dumazet3872d1462022-01-14 08:43:28 -0800[diff] [blame]196 * Paired with the WRITE_ONCE() in unix_inflight(),
197 * unix_notinflight() and gc_in_progress().
Eric Dumazet99156722010-11-24 09:15:27 -0800[diff] [blame]198 */
Eric Dumazet3872d1462022-01-14 08:43:28 -0800[diff] [blame]199 if (READ_ONCE(unix_tot_inflight) > UNIX_INFLIGHT_TRIGGER_GC &&
200 !READ_ONCE(gc_in_progress))
Eric Dumazet99156722010-11-24 09:15:27 -0800[diff] [blame]201 unix_gc();
dann frazier5f23b732008-11-26 15:32:27 -0800[diff] [blame]202 wait_event(unix_gc_wait, gc_in_progress == false);
203}
204
205/* The external entry point: unix_gc() */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]206void unix_gc(void)
207{
Pavel Begunkov813d8fe2022-10-16 22:42:54 +0100[diff] [blame]208 struct sk_buff *next_skb, *skb;
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]209 struct unix_sock *u;
210 struct unix_sock *next;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]211 struct sk_buff_head hitlist;
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]212 struct list_head cursor;
Miklos Szeredi62093442008-11-09 15:23:57 +0100[diff] [blame]213 LIST_HEAD(not_cycle_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]214
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]215 spin_lock(&unix_gc_lock);
216
217 /* Avoid a recursive GC. */
218 if (gc_in_progress)
219 goto out;
220
Eric Dumazet3872d1462022-01-14 08:43:28 -0800[diff] [blame]221 /* Paired with READ_ONCE() in wait_for_unix_gc(). */
222 WRITE_ONCE(gc_in_progress, true);
223
Jason Eastmand1ab39f2015-04-22 00:56:42 -0600[diff] [blame]224 /* First, select candidates for garbage collection. Only
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]225 * in-flight sockets are considered, and from those only ones
226 * which don't have any external reference.
227 *
228 * Holding unix_gc_lock will protect these candidates from
229 * being detached, and hence from gaining an external
Miklos Szeredi62093442008-11-09 15:23:57 +0100[diff] [blame]230 * reference. Since there are no possible receivers, all
231 * buffers currently on the candidates' queues stay there
232 * during the garbage collection.
233 *
234 * We also know that no new candidate can be added onto the
235 * receive queues. Other, non candidate sockets _can_ be
236 * added to queue, so we must make sure only to touch
237 * candidates.
Michal Luczaje8e652b2024-04-09 22:09:39 +0200[diff] [blame^]238 *
239 * Embryos, though never candidates themselves, affect which
240 * candidates are reachable by the garbage collector. Before
241 * being added to a listener's queue, an embryo may already
242 * receive data carrying SCM_RIGHTS, potentially making the
243 * passed socket a candidate that is not yet reachable by the
244 * collector. It becomes reachable once the embryo is
245 * enqueued. Therefore, we must ensure that no SCM-laden
246 * embryo appears in a (candidate) listener's queue between
247 * consecutive scan_children() calls.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]248 */
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]249 list_for_each_entry_safe(u, next, &gc_inflight_list, link) {
Michal Luczaje8e652b2024-04-09 22:09:39 +0200[diff] [blame^]250 struct sock *sk = &u->sk;
Al Viro516e0cc2008-07-26 00:39:17 -0400[diff] [blame]251 long total_refs;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]252
Michal Luczaje8e652b2024-04-09 22:09:39 +0200[diff] [blame^]253 total_refs = file_count(sk->sk_socket->file);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]254
Kuniyuki Iwashima65e0a922024-01-23 09:08:53 -0800[diff] [blame]255 BUG_ON(!u->inflight);
256 BUG_ON(total_refs < u->inflight);
257 if (total_refs == u->inflight) {
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]258 list_move_tail(&u->link, &gc_candidates);
Eric Dumazet60bc8512013-05-01 05:24:03 +0000[diff] [blame]259 __set_bit(UNIX_GC_CANDIDATE, &u->gc_flags);
260 __set_bit(UNIX_GC_MAYBE_CYCLE, &u->gc_flags);
Michal Luczaje8e652b2024-04-09 22:09:39 +0200[diff] [blame^]261
262 if (sk->sk_state == TCP_LISTEN) {
263 unix_state_lock(sk);
264 unix_state_unlock(sk);
265 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]266 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]267 }
268
Jason Eastmand1ab39f2015-04-22 00:56:42 -0600[diff] [blame]269 /* Now remove all internal in-flight reference to children of
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]270 * the candidates.
271 */
272 list_for_each_entry(u, &gc_candidates, link)
273 scan_children(&u->sk, dec_inflight, NULL);
274
Jason Eastmand1ab39f2015-04-22 00:56:42 -0600[diff] [blame]275 /* Restore the references for children of all candidates,
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]276 * which have remaining references. Do this recursively, so
277 * only those remain, which form cyclic references.
278 *
279 * Use a "cursor" link, to make the list traversal safe, even
280 * though elements might be moved about.
281 */
282 list_add(&cursor, &gc_candidates);
283 while (cursor.next != &gc_candidates) {
284 u = list_entry(cursor.next, struct unix_sock, link);
285
286 /* Move cursor to after the current position. */
287 list_move(&cursor, &u->link);
288
Kuniyuki Iwashima65e0a922024-01-23 09:08:53 -0800[diff] [blame]289 if (u->inflight) {
Miklos Szeredi62093442008-11-09 15:23:57 +0100[diff] [blame]290 list_move_tail(&u->link, &not_cycle_list);
Eric Dumazet60bc8512013-05-01 05:24:03 +0000[diff] [blame]291 __clear_bit(UNIX_GC_MAYBE_CYCLE, &u->gc_flags);
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]292 scan_children(&u->sk, inc_inflight_move_tail, NULL);
293 }
294 }
295 list_del(&cursor);
296
Andrey Ulanov7df9c242017-03-14 20:16:42 -0700[diff] [blame]297 /* Now gc_candidates contains only garbage. Restore original
298 * inflight counters for these as well, and remove the skbuffs
299 * which are creating the cycle(s).
300 */
301 skb_queue_head_init(&hitlist);
302 list_for_each_entry(u, &gc_candidates, link)
303 scan_children(&u->sk, inc_inflight, &hitlist);
304
Jason Eastmand1ab39f2015-04-22 00:56:42 -0600[diff] [blame]305 /* not_cycle_list contains those sockets which do not make up a
Miklos Szeredi62093442008-11-09 15:23:57 +0100[diff] [blame]306 * cycle. Restore these to the inflight list.
307 */
308 while (!list_empty(&not_cycle_list)) {
309 u = list_entry(not_cycle_list.next, struct unix_sock, link);
Eric Dumazet60bc8512013-05-01 05:24:03 +0000[diff] [blame]310 __clear_bit(UNIX_GC_CANDIDATE, &u->gc_flags);
Miklos Szeredi62093442008-11-09 15:23:57 +0100[diff] [blame]311 list_move_tail(&u->link, &gc_inflight_list);
312 }
313
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]314 spin_unlock(&unix_gc_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]315
Pavel Begunkov813d8fe2022-10-16 22:42:54 +0100[diff] [blame]316 /* We need io_uring to clean its registered files, ignore all io_uring
317 * originated skbs. It's fine as io_uring doesn't keep references to
318 * other io_uring instances and so killing all other files in the cycle
319 * will put all io_uring references forcing it to go through normal
320 * release.path eventually putting registered files.
321 */
322 skb_queue_walk_safe(&hitlist, skb, next_skb) {
323 if (skb->scm_io_uring) {
324 __skb_unlink(skb, &hitlist);
325 skb_queue_tail(&skb->sk->sk_receive_queue, skb);
326 }
327 }
328
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]329 /* Here we are. Hitlist is filled. Die. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]330 __skb_queue_purge(&hitlist);
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]331
332 spin_lock(&unix_gc_lock);
333
Pavel Begunkov813d8fe2022-10-16 22:42:54 +0100[diff] [blame]334 /* There could be io_uring registered files, just push them back to
335 * the inflight list
336 */
337 list_for_each_entry_safe(u, next, &gc_candidates, link)
338 list_move_tail(&u->link, &gc_inflight_list);
339
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]340 /* All candidates should have been detached by now. */
341 BUG_ON(!list_empty(&gc_candidates));
Eric Dumazet3872d1462022-01-14 08:43:28 -0800[diff] [blame]342
343 /* Paired with READ_ONCE() in wait_for_unix_gc(). */
344 WRITE_ONCE(gc_in_progress, false);
345
dann frazier5f23b732008-11-26 15:32:27 -0800[diff] [blame]346 wake_up(&unix_gc_wait);
Miklos Szeredi1fd05ba2007-07-11 14:22:39 -0700[diff] [blame]347
348 out:
349 spin_unlock(&unix_gc_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]350}