diff options
| author | Paolo Bonzini <pbonzini@redhat.com> | 2016-10-27 12:48:52 +0200 |
|---|---|---|
| committer | Fam Zheng <famz@redhat.com> | 2016-10-28 21:50:18 +0800 |
| commit | 99723548561978da8ef44cf804fb7912698f5d88 (patch) | |
| tree | acb3c6db77507a77a8f275747e12abc2494d6295 /block/block-backend.c | |
| parent | 9a0cec664eefed475a5954006e29f2fd7cd29d2a (diff) | |
| download | qemu-99723548561978da8ef44cf804fb7912698f5d88.tar.gz | |
block: add BDS field to count in-flight requests
Unlike tracked_requests, this field also counts throttled requests,
and remains non-zero if an AIO operation needs a BH to be "really"
completed.
With this change, it is no longer necessary to have a dummy
BdrvTrackedRequest for requests that are never serialising, and
it is no longer necessary to poll the AioContext once after
bdrv_requests_pending(bs) returns false.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-Id: <1477565348-5458-5-git-send-email-pbonzini@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Diffstat (limited to 'block/block-backend.c')
| -rw-r--r-- | block/block-backend.c | 23 |
1 files changed, 19 insertions, 4 deletions
diff --git a/block/block-backend.c b/block/block-backend.c index c53ca30000..bd6316c32a 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -799,20 +799,25 @@ int coroutine_fn blk_co_preadv(BlockBackend *blk, int64_t offset, BdrvRequestFlags flags) { int ret; + BlockDriverState *bs = blk_bs(blk); - trace_blk_co_preadv(blk, blk_bs(blk), offset, bytes, flags); + trace_blk_co_preadv(blk, bs, offset, bytes, flags); ret = blk_check_byte_request(blk, offset, bytes); if (ret < 0) { return ret; } + bdrv_inc_in_flight(bs); + /* throttling disk I/O */ if (blk->public.throttle_state) { throttle_group_co_io_limits_intercept(blk, bytes, false); } - return bdrv_co_preadv(blk->root, offset, bytes, qiov, flags); + ret = bdrv_co_preadv(blk->root, offset, bytes, qiov, flags); + bdrv_dec_in_flight(bs); + return ret; } int coroutine_fn blk_co_pwritev(BlockBackend *blk, int64_t offset, @@ -820,14 +825,17 @@ int coroutine_fn blk_co_pwritev(BlockBackend *blk, int64_t offset, BdrvRequestFlags flags) { int ret; + BlockDriverState *bs = blk_bs(blk); - trace_blk_co_pwritev(blk, blk_bs(blk), offset, bytes, flags); + trace_blk_co_pwritev(blk, bs, offset, bytes, flags); ret = blk_check_byte_request(blk, offset, bytes); if (ret < 0) { return ret; } + bdrv_inc_in_flight(bs); + /* throttling disk I/O */ if (blk->public.throttle_state) { throttle_group_co_io_limits_intercept(blk, bytes, true); @@ -837,7 +845,9 @@ int coroutine_fn blk_co_pwritev(BlockBackend *blk, int64_t offset, flags |= BDRV_REQ_FUA; } - return bdrv_co_pwritev(blk->root, offset, bytes, qiov, flags); + ret = bdrv_co_pwritev(blk->root, offset, bytes, qiov, flags); + bdrv_dec_in_flight(bs); + return ret; } typedef struct BlkRwCo { @@ -930,6 +940,8 @@ int blk_make_zero(BlockBackend *blk, BdrvRequestFlags flags) static void error_callback_bh(void *opaque) { struct BlockBackendAIOCB *acb = opaque; + + bdrv_dec_in_flight(acb->common.bs); acb->common.cb(acb->common.opaque, acb->ret); qemu_aio_unref(acb); } @@ -940,6 +952,7 @@ BlockAIOCB *blk_abort_aio_request(BlockBackend *blk, { struct BlockBackendAIOCB *acb; + bdrv_inc_in_flight(blk_bs(blk)); acb = blk_aio_get(&block_backend_aiocb_info, blk, cb, opaque); acb->blk = blk; acb->ret = ret; @@ -962,6 +975,7 @@ static const AIOCBInfo blk_aio_em_aiocb_info = { static void blk_aio_complete(BlkAioEmAIOCB *acb) { if (acb->has_returned) { + bdrv_dec_in_flight(acb->common.bs); acb->common.cb(acb->common.opaque, acb->rwco.ret); qemu_aio_unref(acb); } @@ -983,6 +997,7 @@ static BlockAIOCB *blk_aio_prwv(BlockBackend *blk, int64_t offset, int bytes, BlkAioEmAIOCB *acb; Coroutine *co; + bdrv_inc_in_flight(blk_bs(blk)); acb = blk_aio_get(&blk_aio_em_aiocb_info, blk, cb, opaque); acb->rwco = (BlkRwCo) { .blk = blk, |