diff options
Diffstat (limited to 'net/sctp/stream_sched_prio.c')
| -rw-r--r-- | net/sctp/stream_sched_prio.c | 85 |
1 files changed, 26 insertions, 59 deletions
diff --git a/net/sctp/stream_sched_prio.c b/net/sctp/stream_sched_prio.c index 2245083a98f2..fb6c55e5615d 100644 --- a/net/sctp/stream_sched_prio.c +++ b/net/sctp/stream_sched_prio.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* SCTP kernel implementation * (C) Copyright Red Hat Inc. 2017 * @@ -5,22 +6,6 @@ * * These functions manipulate sctp stream queue/scheduling. * - * This SCTP implementation is free software; - * you can redistribute it and/or modify it under the terms of - * the GNU General Public License as published by - * the Free Software Foundation; either version 2, or (at your option) - * any later version. - * - * This SCTP implementation 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 General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with GNU CC; see the file COPYING. If not, see - * <http://www.gnu.org/licenses/>. - * * Please send any bug reports or fixes you make to the * email addresched(es): * lksctp developers <linux-sctp@vger.kernel.org> @@ -40,6 +25,18 @@ static void sctp_sched_prio_unsched_all(struct sctp_stream *stream); +static struct sctp_stream_priorities *sctp_sched_prio_head_get(struct sctp_stream_priorities *p) +{ + p->users++; + return p; +} + +static void sctp_sched_prio_head_put(struct sctp_stream_priorities *p) +{ + if (p && --p->users == 0) + kfree(p); +} + static struct sctp_stream_priorities *sctp_sched_prio_new_head( struct sctp_stream *stream, int prio, gfp_t gfp) { @@ -53,6 +50,7 @@ static struct sctp_stream_priorities *sctp_sched_prio_new_head( INIT_LIST_HEAD(&p->active); p->next = NULL; p->prio = prio; + p->users = 1; return p; } @@ -68,7 +66,7 @@ static struct sctp_stream_priorities *sctp_sched_prio_get_head( */ list_for_each_entry(p, &stream->prio_list, prio_sched) { if (p->prio == prio) - return p; + return sctp_sched_prio_head_get(p); if (p->prio > prio) break; } @@ -85,7 +83,7 @@ static struct sctp_stream_priorities *sctp_sched_prio_get_head( */ break; if (p->prio == prio) - return p; + return sctp_sched_prio_head_get(p); } /* If not even there, allocate a new one. */ @@ -169,32 +167,21 @@ static int sctp_sched_prio_set(struct sctp_stream *stream, __u16 sid, struct sctp_stream_out_ext *soute = sout->ext; struct sctp_stream_priorities *prio_head, *old; bool reschedule = false; - int i; + + old = soute->prio_head; + if (old && old->prio == prio) + return 0; prio_head = sctp_sched_prio_get_head(stream, prio, gfp); if (!prio_head) return -ENOMEM; reschedule = sctp_sched_prio_unsched(soute); - old = soute->prio_head; soute->prio_head = prio_head; if (reschedule) sctp_sched_prio_sched(stream, soute); - if (!old) - /* Happens when we set the priority for the first time */ - return 0; - - for (i = 0; i < stream->outcnt; i++) { - soute = SCTP_SO(stream, i)->ext; - if (soute && soute->prio_head == old) - /* It's still in use, nothing else to do here. */ - return 0; - } - - /* No hits, we are good to free it. */ - kfree(old); - + sctp_sched_prio_head_put(old); return 0; } @@ -219,30 +206,10 @@ static int sctp_sched_prio_init_sid(struct sctp_stream *stream, __u16 sid, return sctp_sched_prio_set(stream, sid, 0, gfp); } -static void sctp_sched_prio_free(struct sctp_stream *stream) +static void sctp_sched_prio_free_sid(struct sctp_stream *stream, __u16 sid) { - struct sctp_stream_priorities *prio, *n; - LIST_HEAD(list); - int i; - - /* As we don't keep a list of priorities, to avoid multiple - * frees we have to do it in 3 steps: - * 1. unsched everyone, so the lists are free to use in 2. - * 2. build the list of the priorities - * 3. free the list - */ - sctp_sched_prio_unsched_all(stream); - for (i = 0; i < stream->outcnt; i++) { - if (!SCTP_SO(stream, i)->ext) - continue; - prio = SCTP_SO(stream, i)->ext->prio_head; - if (prio && list_empty(&prio->prio_sched)) - list_add(&prio->prio_sched, &list); - } - list_for_each_entry_safe(prio, n, &list, prio_sched) { - list_del_init(&prio->prio_sched); - kfree(prio); - } + sctp_sched_prio_head_put(SCTP_SO(stream, sid)->ext->prio_head); + SCTP_SO(stream, sid)->ext->prio_head = NULL; } static void sctp_sched_prio_enqueue(struct sctp_outq *q, @@ -333,12 +300,12 @@ static void sctp_sched_prio_unsched_all(struct sctp_stream *stream) sctp_sched_prio_unsched(soute); } -static struct sctp_sched_ops sctp_sched_prio = { +static const struct sctp_sched_ops sctp_sched_prio = { .set = sctp_sched_prio_set, .get = sctp_sched_prio_get, .init = sctp_sched_prio_init, .init_sid = sctp_sched_prio_init_sid, - .free = sctp_sched_prio_free, + .free_sid = sctp_sched_prio_free_sid, .enqueue = sctp_sched_prio_enqueue, .dequeue = sctp_sched_prio_dequeue, .dequeue_done = sctp_sched_prio_dequeue_done, |