We want the BDS event loop to run exclusively in the iothread that
owns the BDS's AioContext. This macro will provide the synchronization
between the two event loops; for now it just wraps the common idiom
of a while loop around aio_poll.
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
v1->v2: make macro name uppercase [Fam]
leave bdrv_wakeup for later [Stefan]
block/block-backend.c | 7 +------
block/io.c | 42 ++++++------------------------------------
block/qed-table.c | 16 ++++------------
include/block/block.h | 9 +++++++++
4 files changed, 20 insertions(+), 54 deletions(-)
diff --git a/block/block-backend.c b/block/block-backend.c
index 234df1e..27cb030 100644
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -878,7 +878,6 @@ static int blk_prw(BlockBackend *blk, int64_t offset,
uint8_t *buf,
int64_t bytes, CoroutineEntry co_entry,
BdrvRequestFlags flags)
{
- AioContext *aio_context;
QEMUIOVector qiov;
struct iovec iov;
Coroutine *co;
@@ -900,11 +899,7 @@ static int blk_prw(BlockBackend *blk, int64_t offset,
uint8_t *buf,
co = qemu_coroutine_create(co_entry, &rwco);
qemu_coroutine_enter(co);
-
- aio_context = blk_get_aio_context(blk);
- while (rwco.ret == NOT_DONE) {
- aio_poll(aio_context, true);
- }
+ BDRV_POLL_WHILE(blk_bs(blk), rwco.ret == NOT_DONE);
return rwco.ret;
}
diff --git a/block/io.c b/block/io.c
index afec968..f0682dd 100644
--- a/block/io.c
+++ b/block/io.c
@@ -156,23 +156,12 @@ bool bdrv_requests_pending(BlockDriverState *bs)
return false;
}
-static bool bdrv_drain_poll(BlockDriverState *bs)
-{
- bool waited = false;
-
- while (atomic_read(&bs->in_flight) > 0) {
- aio_poll(bdrv_get_aio_context(bs), true);
- waited = true;
- }
- return waited;
-}
-
static bool bdrv_drain_recurse(BlockDriverState *bs)
{
BdrvChild *child;
bool waited;
- waited = bdrv_drain_poll(bs);
+ waited = BDRV_POLL_WHILE(bs, atomic_read(&bs->in_flight) > 0);
if (bs->drv && bs->drv->bdrv_drain) {
bs->drv->bdrv_drain(bs);
@@ -597,13 +586,9 @@ static int bdrv_prwv_co(BdrvChild *child, int64_t offset,
/* Fast-path if already in coroutine context */
bdrv_rw_co_entry(&rwco);
} else {
- AioContext *aio_context = bdrv_get_aio_context(child->bs);
-
co = qemu_coroutine_create(bdrv_rw_co_entry, &rwco);
qemu_coroutine_enter(co);
- while (rwco.ret == NOT_DONE) {
- aio_poll(aio_context, true);
- }
+ BDRV_POLL_WHILE(child->bs, rwco.ret == NOT_DONE);
}
return rwco.ret;
}
@@ -1845,14 +1830,10 @@ int64_t bdrv_get_block_status_above(BlockDriverState
*bs,
/* Fast-path if already in coroutine context */
bdrv_get_block_status_above_co_entry(&data);
} else {
- AioContext *aio_context = bdrv_get_aio_context(bs);
-
co = qemu_coroutine_create(bdrv_get_block_status_above_co_entry,
&data);
qemu_coroutine_enter(co);
- while (!data.done) {
- aio_poll(aio_context, true);
- }
+ BDRV_POLL_WHILE(bs, !data.done);
}
return data.ret;
}
@@ -2411,13 +2392,9 @@ int bdrv_flush(BlockDriverState *bs)
/* Fast-path if already in coroutine context */
bdrv_flush_co_entry(&flush_co);
} else {
- AioContext *aio_context = bdrv_get_aio_context(bs);
-
co = qemu_coroutine_create(bdrv_flush_co_entry, &flush_co);
qemu_coroutine_enter(co);
- while (flush_co.ret == NOT_DONE) {
- aio_poll(aio_context, true);
- }
+ BDRV_POLL_WHILE(bs, flush_co.ret == NOT_DONE);
}
return flush_co.ret;
@@ -2543,13 +2520,9 @@ int bdrv_pdiscard(BlockDriverState *bs, int64_t offset,
int count)
/* Fast-path if already in coroutine context */
bdrv_pdiscard_co_entry(&rwco);
} else {
- AioContext *aio_context = bdrv_get_aio_context(bs);
-
co = qemu_coroutine_create(bdrv_pdiscard_co_entry, &rwco);
qemu_coroutine_enter(co);
- while (rwco.ret == NOT_DONE) {
- aio_poll(aio_context, true);
- }
+ BDRV_POLL_WHILE(bs, rwco.ret == NOT_DONE);
}
return rwco.ret;
@@ -2608,11 +2581,8 @@ int bdrv_ioctl(BlockDriverState *bs, unsigned long int
req, void *buf)
bdrv_co_ioctl_entry(&data);
} else {
Coroutine *co = qemu_coroutine_create(bdrv_co_ioctl_entry, &data);
-
qemu_coroutine_enter(co);
- while (data.ret == -EINPROGRESS) {
- aio_poll(bdrv_get_aio_context(bs), true);
- }
+ BDRV_POLL_WHILE(bs, data.ret == -EINPROGRESS);
}
return data.ret;
}
diff --git a/block/qed-table.c b/block/qed-table.c
index 1a731df..ed443e2 100644
--- a/block/qed-table.c
+++ b/block/qed-table.c
@@ -174,9 +174,7 @@ int qed_read_l1_table_sync(BDRVQEDState *s)
qed_read_table(s, s->header.l1_table_offset,
s->l1_table, qed_sync_cb, &ret);
- while (ret == -EINPROGRESS) {
- aio_poll(bdrv_get_aio_context(s->bs), true);
- }
+ BDRV_POLL_WHILE(s->bs, ret == -EINPROGRESS);
return ret;
}
@@ -195,9 +193,7 @@ int qed_write_l1_table_sync(BDRVQEDState *s, unsigned int
index,
int ret = -EINPROGRESS;
qed_write_l1_table(s, index, n, qed_sync_cb, &ret);
- while (ret == -EINPROGRESS) {
- aio_poll(bdrv_get_aio_context(s->bs), true);
- }
+ BDRV_POLL_WHILE(s->bs, ret == -EINPROGRESS);
return ret;
}
@@ -268,9 +264,7 @@ int qed_read_l2_table_sync(BDRVQEDState *s, QEDRequest
*request, uint64_t offset
int ret = -EINPROGRESS;
qed_read_l2_table(s, request, offset, qed_sync_cb, &ret);
- while (ret == -EINPROGRESS) {
- aio_poll(bdrv_get_aio_context(s->bs), true);
- }
+ BDRV_POLL_WHILE(s->bs, ret == -EINPROGRESS);
return ret;
}
@@ -290,9 +284,7 @@ int qed_write_l2_table_sync(BDRVQEDState *s, QEDRequest
*request,
int ret = -EINPROGRESS;
qed_write_l2_table(s, request, index, n, flush, qed_sync_cb, &ret);
- while (ret == -EINPROGRESS) {
- aio_poll(bdrv_get_aio_context(s->bs), true);
- }
+ BDRV_POLL_WHILE(s->bs, ret == -EINPROGRESS);
return ret;
}
diff --git a/include/block/block.h b/include/block/block.h
index 107c603..3ba9e34 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -340,6 +340,15 @@ void bdrv_drain(BlockDriverState *bs);
void coroutine_fn bdrv_co_drain(BlockDriverState *bs);
void bdrv_drain_all(void);
+#define BDRV_POLL_WHILE(bs, cond) ({ \
+ bool waited_ = false; \
+ BlockDriverState *bs_ = (bs); \
+ while ((cond)) { \
+ aio_poll(bdrv_get_aio_context(bs_), true); \
+ waited_ = true; \
+ } \
+ waited_; })
+
int bdrv_pdiscard(BlockDriverState *bs, int64_t offset, int count);
int bdrv_co_pdiscard(BlockDriverState *bs, int64_t offset, int count);
int bdrv_has_zero_init_1(BlockDriverState *bs);
--
2.7.4
