source: mainline/uspace/lib/c/generic/private/fibril.h@ 05208d9

lfn serial ticket/834-toolchain-update topic/msim-upgrade topic/simplify-dev-export
Last change on this file since 05208d9 was 514d561, checked in by Jiří Zárevúcky <jiri.zarevucky@…>, 7 years ago

Fibril/async implementation overhaul.

This commit marks the move towards treating the fibril library as a mere
implementation of a generic threading interface. Understood as a layer that
wraps the kernel threads, we not only have to wrap threading itself, but also
every syscall that blocks the kernel thread (by blocking, we mean thread not
doing useful work until an external event happens — e.g. locking a kernel
mutex or thread sleep is understood as blocking, but an as_area_create() is not,
despite potentially taking a long time to complete).

Consequently, we implement fibril_ipc_wait() as a fibril-native wrapper for
kernel's ipc_wait(), and also implement timer functionality like timeouts
as part of the fibril library. This removes the interdependency between fibril
implementation and the async framework — in theory, the fibril API could be
reimplemented as a simple 1:1 shim, and the async framework would continue
working normally (note that the current implementation of loader complicates
this).

To better isolate the fibril internals from the implementation of high-level
synchronization, a fibril_event_t is added. This object conceptually acts
like a single slot wait queue. All other synchronization is implemented in
terms of this primitive.
  • Property mode set to 100644
File size: 2.3 KB
Line 
1/*
2 * Copyright (c) 2006 Ondrej Palkovsky
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * - Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * - 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.
14 * - The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#ifndef LIBC_PRIVATE_FIBRIL_H_
30#define LIBC_PRIVATE_FIBRIL_H_
31
32#include <adt/list.h>
33#include <context.h>
34#include <tls.h>
35#include <abi/proc/uarg.h>
36#include <atomic.h>
37#include <futex.h>
38
39struct fibril {
40 // XXX: The first two fields must not move (for taskdump).
41 link_t all_link;
42 context_t ctx;
43
44 uspace_arg_t uarg;
45 link_t link;
46 void *stack;
47 size_t stack_size;
48 void *arg;
49 errno_t (*func)(void *);
50 tcb_t *tcb;
51
52 fibril_t *clean_after_me;
53 errno_t retval;
54
55 fibril_t *thread_ctx;
56
57 bool is_running : 1;
58 bool is_writer : 1;
59 /* In some places, we use fibril structs that can't be freed. */
60 bool is_freeable : 1;
61
62 /* Debugging stuff. */
63 atomic_t futex_locks;
64 fibril_owner_info_t *waits_for;
65 fibril_event_t *sleep_event;
66};
67
68extern fibril_t *fibril_alloc(void);
69extern void fibril_setup(fibril_t *);
70extern void fibril_teardown(fibril_t *f);
71extern fibril_t *fibril_self(void);
72
73extern void __fibrils_init(void);
74
75#endif
Note: See TracBrowser for help on using the repository browser.