Vladimir Sementsov-Ogievskiy | e1878eb | 2022-04-07 16:27:23 +0300 | [diff] [blame] | 1 | /* |
| 2 | * Helper functionality for distributing a fixed total amount of |
| 3 | * an abstract resource among multiple coroutines. |
| 4 | * |
| 5 | * Copyright (c) 2022 Virtuozzo International GmbH |
| 6 | * |
| 7 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 8 | * of this software and associated documentation files (the "Software"), to deal |
| 9 | * in the Software without restriction, including without limitation the rights |
| 10 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 11 | * copies of the Software, and to permit persons to whom the Software is |
| 12 | * furnished to do so, subject to the following conditions: |
| 13 | * |
| 14 | * The above copyright notice and this permission notice shall be included in |
| 15 | * all copies or substantial portions of the Software. |
| 16 | * |
| 17 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 18 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 19 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| 20 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 21 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 22 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| 23 | * THE SOFTWARE. |
| 24 | */ |
| 25 | |
| 26 | #include "qemu/osdep.h" |
| 27 | #include "qemu/coroutine.h" |
| 28 | #include "block/aio.h" |
| 29 | |
| 30 | typedef struct QemuCoTimeoutState { |
| 31 | CoroutineEntry *entry; |
| 32 | void *opaque; |
| 33 | QemuCoSleep sleep_state; |
| 34 | bool marker; |
| 35 | CleanupFunc *clean; |
| 36 | } QemuCoTimeoutState; |
| 37 | |
| 38 | static void coroutine_fn qemu_co_timeout_entry(void *opaque) |
| 39 | { |
| 40 | QemuCoTimeoutState *s = opaque; |
| 41 | |
| 42 | s->entry(s->opaque); |
| 43 | |
| 44 | if (s->marker) { |
| 45 | assert(!s->sleep_state.to_wake); |
| 46 | /* .marker set by qemu_co_timeout, it have been failed */ |
| 47 | if (s->clean) { |
| 48 | s->clean(s->opaque); |
| 49 | } |
| 50 | g_free(s); |
| 51 | } else { |
| 52 | s->marker = true; |
| 53 | qemu_co_sleep_wake(&s->sleep_state); |
| 54 | } |
| 55 | } |
| 56 | |
| 57 | int coroutine_fn qemu_co_timeout(CoroutineEntry *entry, void *opaque, |
| 58 | uint64_t timeout_ns, CleanupFunc clean) |
| 59 | { |
| 60 | QemuCoTimeoutState *s; |
| 61 | Coroutine *co; |
| 62 | |
| 63 | if (timeout_ns == 0) { |
| 64 | entry(opaque); |
| 65 | return 0; |
| 66 | } |
| 67 | |
| 68 | s = g_new(QemuCoTimeoutState, 1); |
| 69 | *s = (QemuCoTimeoutState) { |
| 70 | .entry = entry, |
| 71 | .opaque = opaque, |
| 72 | .clean = clean |
| 73 | }; |
| 74 | |
| 75 | co = qemu_coroutine_create(qemu_co_timeout_entry, s); |
| 76 | |
| 77 | aio_co_enter(qemu_get_current_aio_context(), co); |
| 78 | qemu_co_sleep_ns_wakeable(&s->sleep_state, QEMU_CLOCK_REALTIME, timeout_ns); |
| 79 | |
| 80 | if (s->marker) { |
| 81 | /* .marker set by qemu_co_timeout_entry, success */ |
| 82 | g_free(s); |
| 83 | return 0; |
| 84 | } |
| 85 | |
| 86 | /* Don't free s, as we can't cancel qemu_co_timeout_entry execution */ |
| 87 | s->marker = true; |
| 88 | return -ETIMEDOUT; |
| 89 | } |