Re: [Qemu-devel] [RFC v4 17/21] blockjobs: add PENDING status and event

2018-02-28 Thread Kevin Wolf 
Am 24.02.2018 um 00:51 hat John Snow geschrieben:
> For jobs utilizing the new manual workflow, we intend to prohibit
> them from modifying the block graph until the management layer provides
> an explicit ACK via block-job-finalize to move the process forward.
> 
> To distinguish this runstate from "ready" or "waiting," we add a new
> "pending" event.
> 
> For now, the transition from PENDING to CONCLUDED/ABORTING is automatic,
> but a future commit will add the explicit block-job-finalize step.
> 
> Transitions:
> Waiting -> Pending:   Normal transition.
> Pending -> Concluded: Normal transition.
> Pending -> Aborting:  Late transactional failures and cancellations.
> 
> Removed Transitions:
> Waiting -> Concluded: Jobs must go to PENDING first.
> 
> Verbs:
> Cancel: Can be applied to a pending job.
> 
>  +-+
>  |UNDEFINED|
>  +--+--+
> |
>  +--v+
>  |CREATED+-+
>  +--++ |
> |  |
>  +--++ +--+|
>+-+RUNNING<->PAUSED||
>| +--+-+--+ +--+|
>|| ||
>|| +--+ |
>||| |
>| +--v--+   +---+ | |
>+-+READY<--->STANDBY| | |
>| +--+--+   +---+ | |
>||| |
>| +--v+   | |
>+-+WAITING+---+ |
>| +--++ |
>||  |
>| +--v+ |
>+-+PENDING| |
>| +--++ |
>||  |
> +--v-+   +--v--+   |
> |ABORTING+--->CONCLUDED|   |
> ++   +--+--+   |
> |  |
>  +--v-+|
>  |NULL++
>  ++
> 
> Signed-off-by: John Snow 

Your diagram lost two arrow heads in this commit. :-)

Reviewed-by: Kevin Wolf

Re: [Qemu-devel] [RFC v4 17/21] blockjobs: add PENDING status and event

2018-02-27 Thread John Snow 


On 02/27/2018 03:05 PM, Eric Blake wrote:
> On 02/23/2018 05:51 PM, John Snow wrote:
>> For jobs utilizing the new manual workflow, we intend to prohibit
>> them from modifying the block graph until the management layer provides
>> an explicit ACK via block-job-finalize to move the process forward.
>>
>> To distinguish this runstate from "ready" or "waiting," we add a new
>> "pending" event.
>>
>> For now, the transition from PENDING to CONCLUDED/ABORTING is automatic,
>> but a future commit will add the explicit block-job-finalize step.
>>
>> Transitions:
>> Waiting -> Pending:   Normal transition.
>> Pending -> Concluded: Normal transition.
>> Pending -> Aborting:  Late transactional failures and cancellations.
>>
>> Removed Transitions:
>> Waiting -> Concluded: Jobs must go to PENDING first.
>>
>> Verbs:
>> Cancel: Can be applied to a pending job.
>>
> 
>> +##
>> +# @BLOCK_JOB_PENDING:
>> +#
>> +# Emitted when a block job is awaiting explicit authorization to
>> finalize graph
>> +# changes via @block-job-finalize. If this job is part of a
>> transaction, it will
>> +# not emit this event until the transaction has converged first.
> 
> Same question of whether this new event is always emitted (and older
> clients presumably ignore it), or only emitted for clients that
> requested new-style state management.
> 

Old style jobs will skip the broadcast of the event, but will still
transition to the state. However, since transition is synchronous, you
likely won't see this state show up in a query for old style jobs.

That was the intent, anyway.

I wanted to be nonintrusive, and felt that this event was likely not
useful in any way unless we were using the new state management scheme.
In the old style, this event will be fully synchronous with COMPLETED or
CANCELLED, for instance.

--js

Re: [Qemu-devel] [RFC v4 17/21] blockjobs: add PENDING status and event

2018-02-27 Thread Eric Blake 

On 02/23/2018 05:51 PM, John Snow wrote:

For jobs utilizing the new manual workflow, we intend to prohibit
them from modifying the block graph until the management layer provides
an explicit ACK via block-job-finalize to move the process forward.

To distinguish this runstate from "ready" or "waiting," we add a new
"pending" event.

For now, the transition from PENDING to CONCLUDED/ABORTING is automatic,
but a future commit will add the explicit block-job-finalize step.

Transitions:
Waiting -> Pending:   Normal transition.
Pending -> Concluded: Normal transition.
Pending -> Aborting:  Late transactional failures and cancellations.

Removed Transitions:
Waiting -> Concluded: Jobs must go to PENDING first.

Verbs:
Cancel: Can be applied to a pending job.




+##
+# @BLOCK_JOB_PENDING:
+#
+# Emitted when a block job is awaiting explicit authorization to finalize graph
+# changes via @block-job-finalize. If this job is part of a transaction, it 
will
+# not emit this event until the transaction has converged first.


Same question of whether this new event is always emitted (and older 
clients presumably ignore it), or only emitted for clients that 
requested new-style state management.


--
Eric Blake, Principal Software Engineer
Red Hat, Inc.   +1-919-301-3266
Virtualization:  qemu.org | libvirt.org

[Qemu-devel] [RFC v4 17/21] blockjobs: add PENDING status and event

2018-02-23 Thread John Snow 
For jobs utilizing the new manual workflow, we intend to prohibit
them from modifying the block graph until the management layer provides
an explicit ACK via block-job-finalize to move the process forward.

To distinguish this runstate from "ready" or "waiting," we add a new
"pending" event.

For now, the transition from PENDING to CONCLUDED/ABORTING is automatic,
but a future commit will add the explicit block-job-finalize step.

Transitions:
Waiting -> Pending:   Normal transition.
Pending -> Concluded: Normal transition.
Pending -> Aborting:  Late transactional failures and cancellations.

Removed Transitions:
Waiting -> Concluded: Jobs must go to PENDING first.

Verbs:
Cancel: Can be applied to a pending job.

 +-+
 |UNDEFINED|
 +--+--+
|
 +--v+
 |CREATED+-+
 +--++ |
|  |
 +--++ +--+|
   +-+RUNNING<->PAUSED||
   | +--+-+--+ +--+|
   || ||
   || +--+ |
   ||| |
   | +--v--+   +---+ | |
   +-+READY<--->STANDBY| | |
   | +--+--+   +---+ | |
   ||| |
   | +--v+   | |
   +-+WAITING+---+ |
   | +--++ |
   ||  |
   | +--v+ |
   +-+PENDING| |
   | +--++ |
   ||  |
+--v-+   +--v--+   |
|ABORTING+--->CONCLUDED|   |
++   +--+--+   |
|  |
 +--v-+|
 |NULL++
 ++

Signed-off-by: John Snow 
---
 blockjob.c   | 66 +---
 qapi/block-core.json | 31 +++-
 2 files changed, 72 insertions(+), 25 deletions(-)

diff --git a/blockjob.c b/blockjob.c
index 4aed86fc6b..23b4b99fd4 100644
--- a/blockjob.c
+++ b/blockjob.c
@@ -44,27 +44,28 @@ static QemuMutex block_job_mutex;
 
 /* BlockJob State Transition Table */
 bool BlockJobSTT[BLOCK_JOB_STATUS__MAX][BLOCK_JOB_STATUS__MAX] = {
-  /* U, C, R, P, Y, S, W, X, E, N */
-/* U: */ [BLOCK_JOB_STATUS_UNDEFINED] = {0, 1, 0, 0, 0, 0, 0, 0, 0, 0},
-/* C: */ [BLOCK_JOB_STATUS_CREATED]   = {0, 0, 1, 0, 0, 0, 0, 0, 0, 1},
-/* R: */ [BLOCK_JOB_STATUS_RUNNING]   = {0, 0, 0, 1, 1, 0, 1, 1, 0, 0},
-/* P: */ [BLOCK_JOB_STATUS_PAUSED]= {0, 0, 1, 0, 0, 0, 0, 0, 0, 0},
-/* Y: */ [BLOCK_JOB_STATUS_READY] = {0, 0, 0, 0, 0, 1, 1, 1, 0, 0},
-/* S: */ [BLOCK_JOB_STATUS_STANDBY]   = {0, 0, 0, 0, 1, 0, 0, 0, 0, 0},
-/* W: */ [BLOCK_JOB_STATUS_WAITING]   = {0, 0, 0, 0, 0, 0, 0, 1, 1, 0},
-/* X: */ [BLOCK_JOB_STATUS_ABORTING]  = {0, 0, 0, 0, 0, 0, 0, 0, 1, 0},
-/* E: */ [BLOCK_JOB_STATUS_CONCLUDED] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
-/* N: */ [BLOCK_JOB_STATUS_NULL]  = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+  /* U, C, R, P, Y, S, W, D, X, E, N */
+/* U: */ [BLOCK_JOB_STATUS_UNDEFINED] = {0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+/* C: */ [BLOCK_JOB_STATUS_CREATED]   = {0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1},
+/* R: */ [BLOCK_JOB_STATUS_RUNNING]   = {0, 0, 0, 1, 1, 0, 1, 0, 1, 0, 0},
+/* P: */ [BLOCK_JOB_STATUS_PAUSED]= {0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0},
+/* Y: */ [BLOCK_JOB_STATUS_READY] = {0, 0, 0, 0, 0, 1, 1, 0, 1, 0, 0},
+/* S: */ [BLOCK_JOB_STATUS_STANDBY]   = {0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0},
+/* W: */ [BLOCK_JOB_STATUS_WAITING]   = {0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0},
+/* D: */ [BLOCK_JOB_STATUS_PENDING]   = {0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0},
+/* X: */ [BLOCK_JOB_STATUS_ABORTING]  = {0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0},
+/* E: */ [BLOCK_JOB_STATUS_CONCLUDED] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
+/* N: */ [BLOCK_JOB_STATUS_NULL]  = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
 };
 
 bool BlockJobVerbTable[BLOCK_JOB_VERB__MAX][BLOCK_JOB_STATUS__MAX] = {
-  /* U, C, R, P, Y, S, W, X, E, N */
-[BLOCK_JOB_VERB_CANCEL]   = {0, 1, 1, 1, 1, 1, 1, 0, 0, 0},
-[BLOCK_JOB_VERB_PAUSE]= {0, 1, 1, 1, 1, 1, 0, 0, 0, 0},
-[BLOCK_JOB_VERB_RESUME]   = {0, 1, 1, 1, 1, 1, 0, 0, 0, 0},
-[BLOCK_JOB_VERB_SET_SPEED]= {0, 1, 1, 1, 1, 1, 0, 0, 0, 0},
-[BLOCK_JOB_VERB_COMPLETE] = {0, 0, 0, 0, 1, 0, 0, 0, 0, 0},
-[BLOCK_JOB_VERB_DISMISS]  = {0, 0, 0, 0, 0, 0, 0, 0, 1, 0},
+  /* U, C, R, P, Y, S, W, D, X, E, N */
+