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vpc: unlock Coroutine lock to make IO submit Concurrently

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Concurrent IO becomes serial IO because of the qemu Coroutine lock,
which reduce IO performance severely.

So unlock Coroutine lock before bdrv_co_pwritev and
bdrv_co_preadv to fix it.

Signed-off-by: Zhengui li <lizhengui@huawei.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Zhengui li 2019-03-15 22:04:38 +08:00 committed by Kevin Wolf
parent 1bffe1ae7a
commit 126734c4f7
1 changed files with 4 additions and 0 deletions
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4
block/vpc.c
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@ -639,8 +639,10 @@ vpc_co_preadv(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
qemu_iovec_reset(&local_qiov);
qemu_iovec_concat(&local_qiov, qiov, bytes_done, n_bytes);
qemu_co_mutex_unlock(&s->lock);
ret = bdrv_co_preadv(bs->file, image_offset, n_bytes,
&local_qiov, 0);
qemu_co_mutex_lock(&s->lock);
if (ret < 0) {
goto fail;
}
@ -697,8 +699,10 @@ vpc_co_pwritev(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
qemu_iovec_reset(&local_qiov);
qemu_iovec_concat(&local_qiov, qiov, bytes_done, n_bytes);
qemu_co_mutex_unlock(&s->lock);
ret = bdrv_co_pwritev(bs->file, image_offset, n_bytes,
&local_qiov, 0);
qemu_co_mutex_lock(&s->lock);
if (ret < 0) {
goto fail;
}