block: explicit I/O accounting
Decouple the I/O accounting from bdrv_aio_readv/writev/flush and
make the hardware models call directly into the accounting helpers.
This means:
- we do not count internal requests from image formats in addition
to guest originating I/O
- we do not double count I/O ops if the device model handles it
chunk wise
- we only account I/O once it actuall is done
- can extent I/O accounting to synchronous or coroutine I/O easily
- implement I/O latency tracking easily (see the next patch)
I've conveted the existing device model callers to the new model,
device models that are using synchronous I/O and weren't accounted
before haven't been updated yet. Also scsi hasn't been converted
to the end-to-end accounting as I want to defer that after the pending
scsi layer overhaul.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
diff --git a/block.c b/block.c
index 0f256f5..24fba37 100644
--- a/block.c
+++ b/block.c
@@ -1942,13 +1942,13 @@
"'wr_highest_offset': %" PRId64 ","
"'flush_operations': %" PRId64
"} }",
- bs->rd_bytes,
- bs->wr_bytes,
- bs->rd_ops,
- bs->wr_ops,
+ bs->nr_bytes[BDRV_ACCT_READ],
+ bs->nr_bytes[BDRV_ACCT_WRITE],
+ bs->nr_ops[BDRV_ACCT_READ],
+ bs->nr_ops[BDRV_ACCT_WRITE],
bs->wr_highest_sector *
(uint64_t)BDRV_SECTOR_SIZE,
- bs->flush_ops);
+ bs->nr_ops[BDRV_ACCT_FLUSH]);
dict = qobject_to_qdict(res);
if (*bs->device_name) {
@@ -2262,7 +2262,6 @@
return buf;
}
-
/**************************************************************/
/* async I/Os */
@@ -2271,7 +2270,6 @@
BlockDriverCompletionFunc *cb, void *opaque)
{
BlockDriver *drv = bs->drv;
- BlockDriverAIOCB *ret;
trace_bdrv_aio_readv(bs, sector_num, nb_sectors, opaque);
@@ -2280,16 +2278,8 @@
if (bdrv_check_request(bs, sector_num, nb_sectors))
return NULL;
- ret = drv->bdrv_aio_readv(bs, sector_num, qiov, nb_sectors,
- cb, opaque);
-
- if (ret) {
- /* Update stats even though technically transfer has not happened. */
- bs->rd_bytes += (unsigned) nb_sectors * BDRV_SECTOR_SIZE;
- bs->rd_ops++;
- }
-
- return ret;
+ return drv->bdrv_aio_readv(bs, sector_num, qiov, nb_sectors,
+ cb, opaque);
}
typedef struct BlockCompleteData {
@@ -2356,9 +2346,6 @@
cb, opaque);
if (ret) {
- /* Update stats even though technically transfer has not happened. */
- bs->wr_bytes += (unsigned) nb_sectors * BDRV_SECTOR_SIZE;
- bs->wr_ops ++;
if (bs->wr_highest_sector < sector_num + nb_sectors - 1) {
bs->wr_highest_sector = sector_num + nb_sectors - 1;
}
@@ -2612,8 +2599,6 @@
trace_bdrv_aio_flush(bs, opaque);
- bs->flush_ops++;
-
if (bs->open_flags & BDRV_O_NO_FLUSH) {
return bdrv_aio_noop_em(bs, cb, opaque);
}
@@ -3168,6 +3153,25 @@
return bs->in_use;
}
+void
+bdrv_acct_start(BlockDriverState *bs, BlockAcctCookie *cookie, int64_t bytes,
+ enum BlockAcctType type)
+{
+ assert(type < BDRV_MAX_IOTYPE);
+
+ cookie->bytes = bytes;
+ cookie->type = type;
+}
+
+void
+bdrv_acct_done(BlockDriverState *bs, BlockAcctCookie *cookie)
+{
+ assert(cookie->type < BDRV_MAX_IOTYPE);
+
+ bs->nr_bytes[cookie->type] += cookie->bytes;
+ bs->nr_ops[cookie->type]++;
+}
+
int bdrv_img_create(const char *filename, const char *fmt,
const char *base_filename, const char *base_fmt,
char *options, uint64_t img_size, int flags)
