2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 2018, Matthew Macy <mmacy@freebsd.org>
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39 typedef struct epoch *epoch_t;
41 #define EPOCH_PREEMPT 0x1
43 extern epoch_t global_epoch;
44 extern epoch_t global_epoch_preempt;
46 struct epoch_context {
48 } __aligned(sizeof(void *));
50 typedef struct epoch_context *epoch_context_t;
52 epoch_t epoch_alloc(int flags);
53 void epoch_free(epoch_t epoch);
54 void epoch_enter(epoch_t epoch);
55 void epoch_enter_preempt_internal(epoch_t epoch, struct thread *td);
56 void epoch_exit(epoch_t epoch);
57 void epoch_exit_preempt_internal(epoch_t epoch, struct thread *td);
58 void epoch_wait(epoch_t epoch);
59 void epoch_wait_preempt(epoch_t epoch);
60 void epoch_call(epoch_t epoch, epoch_context_t ctx, void (*callback) (epoch_context_t));
64 DPCPU_DECLARE(int, epoch_cb_count);
65 DPCPU_DECLARE(struct grouptask, epoch_cb_task);
68 epoch_enter_preempt(epoch_t epoch)
74 nesting = td->td_epochnest++;
78 epoch_enter_preempt_internal(epoch, td);
82 epoch_exit_preempt(epoch_t epoch)
87 MPASS(td->td_epochnest);
88 if (td->td_epochnest-- == 1)
89 epoch_exit_preempt_internal(epoch, td);