util: add qemu-co-timeout

Add new API, to make a time limited call of the coroutine.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@openvz.org>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
This commit is contained in:
Vladimir Sementsov-Ogievskiy 2022-04-07 16:27:23 +03:00 committed by Vladimir Sementsov-Ogievskiy
parent dd3e97dfbe
commit e1878eb5f0
3 changed files with 103 additions and 0 deletions

View File

@ -331,6 +331,19 @@ static inline void coroutine_fn qemu_co_sleep_ns(QEMUClockType type, int64_t ns)
qemu_co_sleep_ns_wakeable(&w, type, ns);
}
typedef void CleanupFunc(void *opaque);
/**
* Run entry in a coroutine and start timer. Wait for entry to finish or for
* timer to elapse, what happen first. If entry finished, return 0, if timer
* elapsed earlier, return -ETIMEDOUT.
*
* Be careful, entry execution is not canceled, user should handle it somehow.
* If @clean is provided, it's called after coroutine finish if timeout
* happened.
*/
int coroutine_fn qemu_co_timeout(CoroutineEntry *entry, void *opaque,
uint64_t timeout_ns, CleanupFunc clean);
/**
* Wake a coroutine if it is sleeping in qemu_co_sleep_ns. The timer will be
* deleted. @sleep_state must be the variable whose address was given to

View File

@ -85,6 +85,7 @@ if have_block
util_ss.add(files('block-helpers.c'))
util_ss.add(files('qemu-coroutine-sleep.c'))
util_ss.add(files('qemu-co-shared-resource.c'))
util_ss.add(files('qemu-co-timeout.c'))
util_ss.add(files('thread-pool.c', 'qemu-timer.c'))
util_ss.add(files('readline.c'))
util_ss.add(files('throttle.c'))

89
util/qemu-co-timeout.c Normal file
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@ -0,0 +1,89 @@
/*
* Helper functionality for distributing a fixed total amount of
* an abstract resource among multiple coroutines.
*
* Copyright (c) 2022 Virtuozzo International GmbH
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu/osdep.h"
#include "qemu/coroutine.h"
#include "block/aio.h"
typedef struct QemuCoTimeoutState {
CoroutineEntry *entry;
void *opaque;
QemuCoSleep sleep_state;
bool marker;
CleanupFunc *clean;
} QemuCoTimeoutState;
static void coroutine_fn qemu_co_timeout_entry(void *opaque)
{
QemuCoTimeoutState *s = opaque;
s->entry(s->opaque);
if (s->marker) {
assert(!s->sleep_state.to_wake);
/* .marker set by qemu_co_timeout, it have been failed */
if (s->clean) {
s->clean(s->opaque);
}
g_free(s);
} else {
s->marker = true;
qemu_co_sleep_wake(&s->sleep_state);
}
}
int coroutine_fn qemu_co_timeout(CoroutineEntry *entry, void *opaque,
uint64_t timeout_ns, CleanupFunc clean)
{
QemuCoTimeoutState *s;
Coroutine *co;
if (timeout_ns == 0) {
entry(opaque);
return 0;
}
s = g_new(QemuCoTimeoutState, 1);
*s = (QemuCoTimeoutState) {
.entry = entry,
.opaque = opaque,
.clean = clean
};
co = qemu_coroutine_create(qemu_co_timeout_entry, s);
aio_co_enter(qemu_get_current_aio_context(), co);
qemu_co_sleep_ns_wakeable(&s->sleep_state, QEMU_CLOCK_REALTIME, timeout_ns);
if (s->marker) {
/* .marker set by qemu_co_timeout_entry, success */
g_free(s);
return 0;
}
/* Don't free s, as we can't cancel qemu_co_timeout_entry execution */
s->marker = true;
return -ETIMEDOUT;
}