From: Zhu Yangyang <zhuyangyang14@huawei.com>
Calling qmp_block_set_io_throttle() will be blocked for a long time
when a network disk is configured and the network failure is just about
to occur.
Therefore, we add a timeout parameter for qmp_block_set_io_throttle to control
its execution duration.
The default value of timeout is 0, that is infinite wait, consistent with
previous behavior.
Signed-off-by: Zhu Yangyang <zhuyangyang14@huawei.com>
---
block/block-backend.c | 14 +++++++++++++-
block/qapi-system.c | 10 +++++++++-
include/system/block-backend-global-state.h | 1 +
qapi/block-core.json | 5 ++++-
4 files changed, 27 insertions(+), 3 deletions(-)
diff --git a/block/block-backend.c b/block/block-backend.c
index a402db13f2..fc1554ea55 100644
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -2679,20 +2679,32 @@ void blk_set_io_limits(BlockBackend *blk, ThrottleConfig *cfg)
}
void blk_io_limits_disable(BlockBackend *blk)
+{
+ blk_io_limits_disable_timeout(blk, 0);
+}
+
+int blk_io_limits_disable_timeout(BlockBackend *blk, uint64_t timeout_ns)
{
BlockDriverState *bs = blk_bs(blk);
ThrottleGroupMember *tgm = &blk->public.throttle_group_member;
+ int ret = 0;
+
assert(tgm->throttle_state);
GLOBAL_STATE_CODE();
if (bs) {
bdrv_ref(bs);
- bdrv_drained_begin(bs);
+ ret = bdrv_drained_begin_timeout(bs, timeout_ns);
+ if (ret < 0) {
+ goto out;
+ }
}
throttle_group_unregister_tgm(tgm);
+out:
if (bs) {
bdrv_drained_end(bs);
bdrv_unref(bs);
}
+ return ret;
}
/* should be called before blk_set_io_limits if a limit is set */
diff --git a/block/qapi-system.c b/block/qapi-system.c
index 54b7409b2b..3b7ba0959c 100644
--- a/block/qapi-system.c
+++ b/block/qapi-system.c
@@ -423,6 +423,7 @@ void qmp_block_set_io_throttle(BlockIOThrottle *arg, Error **errp)
ThrottleConfig cfg;
BlockDriverState *bs;
BlockBackend *blk;
+ uint64_t timeout_ns;
blk = qmp_get_blk(arg->device, arg->id, errp);
if (!blk) {
@@ -444,6 +445,10 @@ void qmp_block_set_io_throttle(BlockIOThrottle *arg, Error **errp)
cfg.buckets[THROTTLE_OPS_READ].avg = arg->iops_rd;
cfg.buckets[THROTTLE_OPS_WRITE].avg = arg->iops_wr;
+ timeout_ns = 0; /* 0 means infinite */
+ if (arg->has_timeout) {
+ timeout_ns = arg->timeout * NANOSECONDS_PER_SECOND;
+ }
if (arg->has_bps_max) {
cfg.buckets[THROTTLE_BPS_TOTAL].max = arg->bps_max;
}
@@ -502,7 +507,10 @@ void qmp_block_set_io_throttle(BlockIOThrottle *arg, Error **errp)
blk_set_io_limits(blk, &cfg);
} else if (blk_get_public(blk)->throttle_group_member.throttle_state) {
/* If all throttling settings are set to 0, disable I/O limits */
- blk_io_limits_disable(blk);
+ if (blk_io_limits_disable_timeout(blk, timeout_ns) < 0) {
+ error_setg(errp, "Blk io limits disable timeout");
+ return;
+ }
}
}
diff --git a/include/system/block-backend-global-state.h b/include/system/block-backend-global-state.h
index 35b5e8380b..8a2a6cbda4 100644
--- a/include/system/block-backend-global-state.h
+++ b/include/system/block-backend-global-state.h
@@ -110,6 +110,7 @@ int blk_probe_geometry(BlockBackend *blk, HDGeometry *geo);
void blk_set_io_limits(BlockBackend *blk, ThrottleConfig *cfg);
void blk_io_limits_disable(BlockBackend *blk);
+int blk_io_limits_disable_timeout(BlockBackend *blk, uint64_t timeout_ns);
void blk_io_limits_enable(BlockBackend *blk, const char *group);
void blk_io_limits_update_group(BlockBackend *blk, const char *group);
void blk_set_force_allow_inactivate(BlockBackend *blk);
diff --git a/qapi/block-core.json b/qapi/block-core.json
index b1937780e1..88ef593efd 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -2626,6 +2626,9 @@
#
# @group: throttle group name (Since 2.4)
#
+# @timeout: In seconds. Timeout for block_set_io_throttle,
+# 0 means no limit. Defaults to 0. (Since 10.0)
+#
# Features:
#
# @deprecated: Member @device is deprecated. Use @id instead.
@@ -2642,7 +2645,7 @@
'*bps_max_length': 'int', '*bps_rd_max_length': 'int',
'*bps_wr_max_length': 'int', '*iops_max_length': 'int',
'*iops_rd_max_length': 'int', '*iops_wr_max_length': 'int',
- '*iops_size': 'int', '*group': 'str' } }
+ '*iops_size': 'int', '*group': 'str', '*timeout': 'uint32'} }
##
# @ThrottleLimits:
--
2.33.0zoudongjie via <qemu-devel@nongnu.org> writes: > From: Zhu Yangyang <zhuyangyang14@huawei.com> > > Calling qmp_block_set_io_throttle() will be blocked for a long time > when a network disk is configured and the network failure is just about > to occur. > > Therefore, we add a timeout parameter for qmp_block_set_io_throttle to control > its execution duration. What's the QMP reply when a block_set_io_throttle command times out? > > The default value of timeout is 0, that is infinite wait, consistent with > previous behavior. > > Signed-off-by: Zhu Yangyang <zhuyangyang14@huawei.com> [...] > diff --git a/qapi/block-core.json b/qapi/block-core.json > index b1937780e1..88ef593efd 100644 > --- a/qapi/block-core.json > +++ b/qapi/block-core.json > @@ -2626,6 +2626,9 @@ > # > # @group: throttle group name (Since 2.4) > # > +# @timeout: In seconds. Timeout for block_set_io_throttle, > +# 0 means no limit. Defaults to 0. (Since 10.0) Make that 10.1, since it won't make 10.0. > +# > # Features: > # > # @deprecated: Member @device is deprecated. Use @id instead. > @@ -2642,7 +2645,7 @@ > '*bps_max_length': 'int', '*bps_rd_max_length': 'int', > '*bps_wr_max_length': 'int', '*iops_max_length': 'int', > '*iops_rd_max_length': 'int', '*iops_wr_max_length': 'int', > - '*iops_size': 'int', '*group': 'str' } } > + '*iops_size': 'int', '*group': 'str', '*timeout': 'uint32'} } > > ## > # @ThrottleLimits:
On Wed, Mar 26, 2025 at 10:53:20 +0100, Markus wrote:
> zoudongjie via <qemu-devel@nongnu.org> writes:
>
> > From: Zhu Yangyang <zhuyangyang14@huawei.com>
> >
> > Calling qmp_block_set_io_throttle() will be blocked for a long time
> > when a network disk is configured and the network failure is just about
> > to occur.
> >
> > Therefore, we add a timeout parameter for qmp_block_set_io_throttle to control
> > its execution duration.
>
> What's the QMP reply when a block_set_io_throttle command times out?
The reply is:
{"id":"libvirt-484","error":{"class":"GenericError","desc":"Blk io limits disable timeout"}}
>
> >
> > The default value of timeout is 0, that is infinite wait, consistent with
> > previous behavior.
> >
> > Signed-off-by: Zhu Yangyang <zhuyangyang14@huawei.com>
>
> [...]
>
> > diff --git a/qapi/block-core.json b/qapi/block-core.json
> > index b1937780e1..88ef593efd 100644
> > --- a/qapi/block-core.json
> > +++ b/qapi/block-core.json
> > @@ -2626,6 +2626,9 @@
> > #
> > # @group: throttle group name (Since 2.4)
> > #
> > +# @timeout: In seconds. Timeout for block_set_io_throttle,
> > +# 0 means no limit. Defaults to 0. (Since 10.0)
>
> Make that 10.1, since it won't make 10.0.
Ok, I'll correct it in the next version.
>
> > +#
> > # Features:
> > #
> > # @deprecated: Member @device is deprecated. Use @id instead.
> > @@ -2642,7 +2645,7 @@
> > '*bps_max_length': 'int', '*bps_rd_max_length': 'int',
> > '*bps_wr_max_length': 'int', '*iops_max_length': 'int',
> > '*iops_rd_max_length': 'int', '*iops_wr_max_length': 'int',
> > - '*iops_size': 'int', '*group': 'str' } }
> > + '*iops_size': 'int', '*group': 'str', '*timeout': 'uint32'} }
> >
> > ##
> > # @ThrottleLimits:
zoudongjie <zoudongjie@huawei.com> writes:
> On Wed, Mar 26, 2025 at 10:53:20 +0100, Markus wrote:
>> zoudongjie via <qemu-devel@nongnu.org> writes:
>>
>> > From: Zhu Yangyang <zhuyangyang14@huawei.com>
>> >
>> > Calling qmp_block_set_io_throttle() will be blocked for a long time
>> > when a network disk is configured and the network failure is just about
>> > to occur.
What other commands could similarly block?
>> > Therefore, we add a timeout parameter for qmp_block_set_io_throttle to control
>> > its execution duration.
>>
>> What's the QMP reply when a block_set_io_throttle command times out?
>
> The reply is:
> {"id":"libvirt-484","error":{"class":"GenericError","desc":"Blk io limits disable timeout"}}
I find the error message confusing. Suggest "command timed out".
>> >
>> > The default value of timeout is 0, that is infinite wait, consistent with
>> > previous behavior.
>> >
>> > Signed-off-by: Zhu Yangyang <zhuyangyang14@huawei.com>
[...]
On Thu, 27 Mar 2025 09:04:51 +0100, Markus wrote:
> zoudongjie <zoudongjie@huawei.com> writes:
>
> > On Wed, Mar 26, 2025 at 10:53:20 +0100, Markus wrote:
> >> zoudongjie via <qemu-devel@nongnu.org> writes:
> >>
> >> > From: Zhu Yangyang <zhuyangyang14@huawei.com>
> >> >
> >> > Calling qmp_block_set_io_throttle() will be blocked for a long time
> >> > when a network disk is configured and the network failure is just about
> >> > to occur.
>
> What other commands could similarly block?
In theory, any command may be blocked if it calls bdrv_drained_begin().
I did a quick check, qmp_block_resize() could similarly block, since it called
bdrv_drained_begin(), I'm going to verify it later.
>
> >> > Therefore, we add a timeout parameter for qmp_block_set_io_throttle to control
> >> > its execution duration.
> >>
> >> What's the QMP reply when a block_set_io_throttle command times out?
> >
> > The reply is:
> > {"id":"libvirt-484","error":{"class":"GenericError","desc":"Blk io limits disable timeout"}}
>
> I find the error message confusing. Suggest "command timed out".
This message doesn't provide more details about the error, especially for developers.
How about using "command timed out: disable I/O limits"
>
> >> >
> >> > The default value of timeout is 0, that is infinite wait, consistent with
> >> > previous behavior.
> >> >
> >> > Signed-off-by: Zhu Yangyang <zhuyangyang14@huawei.com>
>
> [...]
On Thu, 27 Mar 2025 09:04:51 +0100, Markus wrote:
> zoudongjie <zoudongjie@huawei.com> writes:
>
> > On Wed, Mar 26, 2025 at 10:53:20 +0100, Markus wrote:
> >> zoudongjie via <qemu-devel@nongnu.org> writes:
> >>
> >> > From: Zhu Yangyang <zhuyangyang14@huawei.com>
> >> >
> >> > Calling qmp_block_set_io_throttle() will be blocked for a long time
> >> > when a network disk is configured and the network failure is just about
> >> > to occur.
>
> What other commands could similarly block?
In theory, any command may be blocked if it calls bdrv_drained_begin().
I did a quick check, qmp_block_resize() could similarly block, since it called
bdrv_drained_begin(), I'm going to verify it later.
>
> >> > Therefore, we add a timeout parameter for qmp_block_set_io_throttle to control
> >> > its execution duration.
> >>
> >> What's the QMP reply when a block_set_io_throttle command times out?
> >
> > The reply is:
> > {"id":"libvirt-484","error":{"class":"GenericError","desc":"Blk io limits disable timeout"}}
>
> I find the error message confusing. Suggest "command timed out".
This message doesn't provide more details about the error, especially for developers.
How about using "command timed out: disable I/O limits"
>
> >> >
> >> > The default value of timeout is 0, that is infinite wait, consistent with
> >> > previous behavior.
> >> >
> >> > Signed-off-by: Zhu Yangyang <zhuyangyang14@huawei.com>
>
> [...]
zoudongjie <zoudongjie@huawei.com> writes:
> On Thu, 27 Mar 2025 09:04:51 +0100, Markus wrote:
>> zoudongjie <zoudongjie@huawei.com> writes:
>>
>> > On Wed, Mar 26, 2025 at 10:53:20 +0100, Markus wrote:
>> >> zoudongjie via <qemu-devel@nongnu.org> writes:
>> >>
>> >> > From: Zhu Yangyang <zhuyangyang14@huawei.com>
>> >> >
>> >> > Calling qmp_block_set_io_throttle() will be blocked for a long time
>> >> > when a network disk is configured and the network failure is just about
>> >> > to occur.
>>
>> What other commands could similarly block?
>
> In theory, any command may be blocked if it calls bdrv_drained_begin().
> I did a quick check, qmp_block_resize() could similarly block, since it called
> bdrv_drained_begin(), I'm going to verify it later.
Please do.
Should all these commands support time out?
>> >> > Therefore, we add a timeout parameter for qmp_block_set_io_throttle to control
>> >> > its execution duration.
>> >>
>> >> What's the QMP reply when a block_set_io_throttle command times out?
>> >
>> > The reply is:
>> > {"id":"libvirt-484","error":{"class":"GenericError","desc":"Blk io limits disable timeout"}}
>>
>> I find the error message confusing. Suggest "command timed out".
>
> This message doesn't provide more details about the error, especially for developers.
> How about using "command timed out: disable I/O limits"
I don't get what "disable I/O limits" is trying to tell the user. Can
you explain?
>> >> > The default value of timeout is 0, that is infinite wait, consistent with
>> >> > previous behavior.
>> >> >
>> >> > Signed-off-by: Zhu Yangyang <zhuyangyang14@huawei.com>
>>
>> [...]
I'm sorry for the delay in replying.
On Thu, 27 Mar 2025 14:43:54 +0100, Markus wrote:
> zoudongjie <zoudongjie@huawei.com> writes:
> > On Thu, 27 Mar 2025 09:04:51 +0100, Markus wrote:
> >> zoudongjie <zoudongjie@huawei.com> writes:
> >>
> >> > On Wed, Mar 26, 2025 at 10:53:20 +0100, Markus wrote:
> >> >> zoudongjie via <qemu-devel@nongnu.org> writes:
> >> >>
> >> >> > From: Zhu Yangyang <zhuyangyang14@huawei.com>
> >> >> >
> >> >> > Calling qmp_block_set_io_throttle() will be blocked for a long time
> >> >> > when a network disk is configured and the network failure is just about
> >> >> > to occur.
> >>
> >> What other commands could similarly block?
> >
> > In theory, any command may be blocked if it calls bdrv_drained_begin().
> > I did a quick check, qmp_block_resize() could similarly block, since it called
> > bdrv_drained_begin(), I'm going to verify it later.
>
> Please do.
>
> Should all these commands support time out?
Yes, I think it is.
Later in v4, I'll add timeout support for qmp_block_resize().
If I find a similar block command in the future, I'll email again.
>
> >> >> > Therefore, we add a timeout parameter for qmp_block_set_io_throttle to control
> >> >> > its execution duration.
> >> >>
> >> >> What's the QMP reply when a block_set_io_throttle command times out?
> >> >
> >> > The reply is:
> >> > {"id":"libvirt-484","error":{"class":"GenericError","desc":"Blk io limits disable timeout"}}
> >>
> >> I find the error message confusing. Suggest "command timed out".
> >
> > This message doesn't provide more details about the error, especially for developers.
> > How about using "command timed out: disable I/O limits"
>
> I don't get what "disable I/O limits" is trying to tell the user. Can
> you explain?
In fact, block_set_io_throttle() has two branches: enable io limits
and disable io limits. If there is a possibility of timeout in both
branches in command, detailed reason may be useful. But now "command timed out"
is enough and I will use it in v4.
>
> >> >> > The default value of timeout is 0, that is infinite wait, consistent with
> >> >> > previous behavior.
> >> >> >
> >> >> > Signed-off-by: Zhu Yangyang <zhuyangyang14@huawei.com>
> >>
> >> [...]
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