bdrv_is_allocated can detect coroutine context and go through a fast
path, similar to other block layer functions.
Reviewed-by: Eric Blake <ebl...@redhat.com>
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
block.c | 24 +++++++++++++++---------
block/raw.c | 2 +-
block/stream.c | 4 ++--
include/block/block.h | 2 --
4 files changed, 18 insertions(+), 14 deletions(-)
diff --git a/block.c b/block.c
index ebac2fa..dd4c570 100644
--- a/block.c
+++ b/block.c
@@ -2527,7 +2527,7 @@ static int coroutine_fn bdrv_co_do_readv(BlockDriverState
*bs,
if (flags & BDRV_REQ_COPY_ON_READ) {
int pnum;
- ret = bdrv_co_is_allocated(bs, sector_num, nb_sectors, &pnum);
+ ret = bdrv_is_allocated(bs, sector_num, nb_sectors, &pnum);
if (ret < 0) {
goto out;
}
@@ -2981,8 +2981,9 @@ typedef struct BdrvCoIsAllocatedData {
* 'nb_sectors' is the max value 'pnum' should be set to. If nb_sectors goes
* beyond the end of the disk image it will be clamped.
*/
-int coroutine_fn bdrv_co_is_allocated(BlockDriverState *bs, int64_t sector_num,
- int nb_sectors, int *pnum)
+static int coroutine_fn bdrv_co_is_allocated(BlockDriverState *bs,
+ int64_t sector_num,
+ int nb_sectors, int *pnum)
{
int64_t n;
@@ -3032,10 +3033,15 @@ int bdrv_is_allocated(BlockDriverState *bs, int64_t
sector_num, int nb_sectors,
.done = false,
};
- co = qemu_coroutine_create(bdrv_is_allocated_co_entry);
- qemu_coroutine_enter(co, &data);
- while (!data.done) {
- qemu_aio_wait();
+ if (qemu_in_coroutine()) {
+ /* Fast-path if already in coroutine context */
+ bdrv_is_allocated_co_entry(&data);
+ } else {
+ co = qemu_coroutine_create(bdrv_is_allocated_co_entry);
+ qemu_coroutine_enter(co, &data);
+ while (!data.done) {
+ qemu_aio_wait();
+ }
}
return data.ret;
}
@@ -3063,8 +3069,8 @@ int coroutine_fn
bdrv_co_is_allocated_above(BlockDriverState *top,
intermediate = top;
while (intermediate && intermediate != base) {
int pnum_inter;
- ret = bdrv_co_is_allocated(intermediate, sector_num, nb_sectors,
- &pnum_inter);
+ ret = bdrv_is_allocated(intermediate, sector_num, nb_sectors,
+ &pnum_inter);
if (ret < 0) {
return ret;
} else if (ret) {
diff --git a/block/raw.c b/block/raw.c
index f1682d4..4517a81 100644
--- a/block/raw.c
+++ b/block/raw.c
@@ -39,7 +39,7 @@ static int coroutine_fn raw_co_is_allocated(BlockDriverState
*bs,
int64_t sector_num,
int nb_sectors, int *pnum)
{
- return bdrv_co_is_allocated(bs->file, sector_num, nb_sectors, pnum);
+ return bdrv_is_allocated(bs->file, sector_num, nb_sectors, pnum);
}
static int coroutine_fn raw_co_write_zeroes(BlockDriverState *bs,
diff --git a/block/stream.c b/block/stream.c
index 7fe9e48..fb1f9c3 100644
--- a/block/stream.c
+++ b/block/stream.c
@@ -115,8 +115,8 @@ wait:
break;
}
- ret = bdrv_co_is_allocated(bs, sector_num,
- STREAM_BUFFER_SIZE / BDRV_SECTOR_SIZE, &n);
+ ret = bdrv_is_allocated(bs, sector_num,
+ STREAM_BUFFER_SIZE / BDRV_SECTOR_SIZE, &n);
if (ret == 1) {
/* Allocated in the top, no need to copy. */
copy = false;
diff --git a/include/block/block.h b/include/block/block.h
index 742fce5..dde745f 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -181,8 +181,6 @@ int coroutine_fn bdrv_co_writev(BlockDriverState *bs,
int64_t sector_num,
*/
int coroutine_fn bdrv_co_write_zeroes(BlockDriverState *bs, int64_t sector_num,
int nb_sectors);
-int coroutine_fn bdrv_co_is_allocated(BlockDriverState *bs, int64_t sector_num,
- int nb_sectors, int *pnum);
int coroutine_fn bdrv_co_is_allocated_above(BlockDriverState *top,
BlockDriverState *base,
int64_t sector_num,
--
1.8.3.1
