On Wed, May 17, 2023 at 06:10:19PM -0400, Stefan Hajnoczi wrote:
Stop using the .bdrv_co_io_plug() API because it is not multi-queue
block layer friendly. Use the new blk_io_plug_call() API to batch I/O
submission instead.
Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com>
---
block/blkio.c | 40 +++++++++++++++++++++-------------------
1 file changed, 21 insertions(+), 19 deletions(-)
With this patch, the build fails in several places, maybe it's an old
version:
../block/blkio.c:347:5: error: implicit declaration of function
‘blk_io_plug_call’ [-Werror=implicit-function-declaration]
347 | blk_io_plug_call(blkio_unplug_fn, bs);
../block/blkio.c:348:22: error: passing argument 1 of ‘blk_io_plug_call’
from incompatible pointer type [-Werror=incompatible-pointer-types]
348 | blk_io_plug_call(blkio_unplug_fn, bs);
Thanks,
Stefano
diff --git a/block/blkio.c b/block/blkio.c
index 0cdc99a729..f2a1dc1fb2 100644
--- a/block/blkio.c
+++ b/block/blkio.c
@@ -325,16 +325,28 @@ static void blkio_detach_aio_context(BlockDriverState *bs)
false, NULL, NULL, NULL, NULL, NULL);
}
-/* Call with s->blkio_lock held to submit I/O after enqueuing a new request */
-static void blkio_submit_io(BlockDriverState *bs)
+/*
+ * Called by blk_io_unplug() or immediately if not plugged. Called without
+ * blkio_lock.
+ */
+static void blkio_unplug_fn(BlockDriverState *bs)
{
- if (qatomic_read(&bs->io_plugged) == 0) {
- BDRVBlkioState *s = bs->opaque;
+ BDRVBlkioState *s = bs->opaque;
+ WITH_QEMU_LOCK_GUARD(&s->blkio_lock) {
blkioq_do_io(s->blkioq, NULL, 0, 0, NULL);
}
}
+/*
+ * Schedule I/O submission after enqueuing a new request. Called without
+ * blkio_lock.
+ */
+static void blkio_submit_io(BlockDriverState *bs)
+{
+ blk_io_plug_call(blkio_unplug_fn, bs);
+}
+
static int coroutine_fn
blkio_co_pdiscard(BlockDriverState *bs, int64_t offset, int64_t bytes)
{
@@ -345,9 +357,9 @@ blkio_co_pdiscard(BlockDriverState *bs, int64_t offset,
int64_t bytes)
WITH_QEMU_LOCK_GUARD(&s->blkio_lock) {
blkioq_discard(s->blkioq, offset, bytes, &cod, 0);
- blkio_submit_io(bs);
}
+ blkio_submit_io(bs);
qemu_coroutine_yield();
return cod.ret;
}
@@ -378,9 +390,9 @@ blkio_co_preadv(BlockDriverState *bs, int64_t offset,
int64_t bytes,
WITH_QEMU_LOCK_GUARD(&s->blkio_lock) {
blkioq_readv(s->blkioq, offset, iov, iovcnt, &cod, 0);
- blkio_submit_io(bs);
}
+ blkio_submit_io(bs);
qemu_coroutine_yield();
if (use_bounce_buffer) {
@@ -423,9 +435,9 @@ static int coroutine_fn blkio_co_pwritev(BlockDriverState
*bs, int64_t offset,
WITH_QEMU_LOCK_GUARD(&s->blkio_lock) {
blkioq_writev(s->blkioq, offset, iov, iovcnt, &cod, blkio_flags);
- blkio_submit_io(bs);
}
+ blkio_submit_io(bs);
qemu_coroutine_yield();
if (use_bounce_buffer) {
@@ -444,9 +456,9 @@ static int coroutine_fn blkio_co_flush(BlockDriverState *bs)
WITH_QEMU_LOCK_GUARD(&s->blkio_lock) {
blkioq_flush(s->blkioq, &cod, 0);
- blkio_submit_io(bs);
}
+ blkio_submit_io(bs);
qemu_coroutine_yield();
return cod.ret;
}
@@ -472,22 +484,13 @@ static int coroutine_fn
blkio_co_pwrite_zeroes(BlockDriverState *bs,
WITH_QEMU_LOCK_GUARD(&s->blkio_lock) {
blkioq_write_zeroes(s->blkioq, offset, bytes, &cod, blkio_flags);
- blkio_submit_io(bs);
}
+ blkio_submit_io(bs);
qemu_coroutine_yield();
return cod.ret;
}
-static void coroutine_fn blkio_co_io_unplug(BlockDriverState *bs)
-{
- BDRVBlkioState *s = bs->opaque;
-
- WITH_QEMU_LOCK_GUARD(&s->blkio_lock) {
- blkio_submit_io(bs);
- }
-}
-
typedef enum {
BMRR_OK,
BMRR_SKIP,
@@ -1009,7 +1012,6 @@ static void blkio_refresh_limits(BlockDriverState *bs,
Error **errp)
.bdrv_co_pwritev = blkio_co_pwritev, \
.bdrv_co_flush_to_disk = blkio_co_flush, \
.bdrv_co_pwrite_zeroes = blkio_co_pwrite_zeroes, \
- .bdrv_co_io_unplug = blkio_co_io_unplug, \
.bdrv_refresh_limits = blkio_refresh_limits, \
.bdrv_register_buf = blkio_register_buf, \
.bdrv_unregister_buf = blkio_unregister_buf, \
--
2.40.1
