qemu/util/qemu-coroutine-sleep.c
Stefan Hajnoczi 78f1d3d6a6 coroutine: simplify co_aio_sleep_ns() prototype
The AioContext pointer argument to co_aio_sleep_ns() is only used for
the sleep timer.  It does not affect where the caller coroutine is
resumed.

Due to changes to coroutine and AIO APIs it is now possible to drop the
AioContext pointer argument.  This is safe to do since no caller has
specific requirements for which AioContext the timer must run in.

This patch drops the AioContext pointer argument and renames the
function to simplify the API.

Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Reported-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20171109102652.6360-1-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-12-19 09:25:27 +00:00

54 lines
1.4 KiB
C

/*
* QEMU coroutine sleep
*
* Copyright IBM, Corp. 2011
*
* Authors:
* Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
*
* This work is licensed under the terms of the GNU LGPL, version 2 or later.
* See the COPYING.LIB file in the top-level directory.
*
*/
#include "qemu/osdep.h"
#include "qemu/coroutine.h"
#include "qemu/coroutine_int.h"
#include "qemu/timer.h"
#include "block/aio.h"
typedef struct CoSleepCB {
QEMUTimer *ts;
Coroutine *co;
} CoSleepCB;
static void co_sleep_cb(void *opaque)
{
CoSleepCB *sleep_cb = opaque;
/* Write of schedule protected by barrier write in aio_co_schedule */
atomic_set(&sleep_cb->co->scheduled, NULL);
aio_co_wake(sleep_cb->co);
}
void coroutine_fn qemu_co_sleep_ns(QEMUClockType type, int64_t ns)
{
AioContext *ctx = qemu_get_current_aio_context();
CoSleepCB sleep_cb = {
.co = qemu_coroutine_self(),
};
const char *scheduled = atomic_cmpxchg(&sleep_cb.co->scheduled, NULL,
__func__);
if (scheduled) {
fprintf(stderr,
"%s: Co-routine was already scheduled in '%s'\n",
__func__, scheduled);
abort();
}
sleep_cb.ts = aio_timer_new(ctx, type, SCALE_NS, co_sleep_cb, &sleep_cb);
timer_mod(sleep_cb.ts, qemu_clock_get_ns(type) + ns);
qemu_coroutine_yield();
timer_del(sleep_cb.ts);
timer_free(sleep_cb.ts);
}