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linux-aio: simplify removal of completed iocbs from the list

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There is no need to do another O(n) pass on the list; the iocb to
split the list at is already available through the array we passed to
io_submit.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1418305950-30924-6-git-send-email-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Paolo Bonzini 2014-12-11 14:52:30 +01:00 committed by Stefan Hajnoczi
parent de35464461
commit 82595da8de
2 changed files with 17 additions and 6 deletions
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12
block/linux-aio.c
View File

@ -186,9 +186,10 @@ static void ioq_init(LaioQueue *io_q)
static void ioq_submit(struct qemu_laio_state *s)
{
int ret, i, len;
int ret, len;
struct qemu_laiocb *aiocb;
struct iocb *iocbs[MAX_QUEUED_IO];
QSIMPLEQ_HEAD(, qemu_laiocb) completed;
do {
len = 0;
@ -201,16 +202,15 @@ static void ioq_submit(struct qemu_laio_state *s)
ret = io_submit(s->ctx, len, iocbs);
if (ret == -EAGAIN) {
ret = 0;
break;
}
if (ret < 0) {
abort();
}
for (i = 0; i < ret; i++) {
s->io_q.n--;
QSIMPLEQ_REMOVE_HEAD(&s->io_q.pending, next);
}
s->io_q.n -= ret;
aiocb = container_of(iocbs[ret - 1], struct qemu_laiocb, iocb);
QSIMPLEQ_SPLIT_AFTER(&s->io_q.pending, aiocb, next, &completed);
} while (ret == len && !QSIMPLEQ_EMPTY(&s->io_q.pending));
s->io_q.blocked = (s->io_q.n > 0);
}

11
include/qemu/queue.h
View File

@ -268,6 +268,17 @@ struct { \
(head)->sqh_last = &(head)->sqh_first; \
} while (/*CONSTCOND*/0)
#define QSIMPLEQ_SPLIT_AFTER(head, elm, field, removed) do { \
QSIMPLEQ_INIT(removed); \
if (((removed)->sqh_first = (head)->sqh_first) != NULL) { \
if (((head)->sqh_first = (elm)->field.sqe_next) == NULL) { \
(head)->sqh_last = &(head)->sqh_first; \
} \
(removed)->sqh_last = &(elm)->field.sqe_next; \
(elm)->field.sqe_next = NULL; \
} \
} while (/*CONSTCOND*/0)
#define QSIMPLEQ_REMOVE(head, elm, type, field) do { \
if ((head)->sqh_first == (elm)) { \
QSIMPLEQ_REMOVE_HEAD((head), field); \