On 02/11/2021 13:41, Vladimir Sementsov-Ogievskiy wrote:
Hmm. subject looks like it's safe to remove aiocontext locks from any
qmp command?
For example, commit 91005a495e228eb added aiocontext locks back to qmp
bitmap add/remove commands because otherwise they crashed.
So, I'm not sure that being under BQL is enough to drop aiocontext
locking..
In this specific case the aiocontext is useless there. I am not sure
what it was used for before, but if you look at what it protects in this
patch we have:
- block_job_query: not called by anyone else, and internally calls:
* block_job_is_internal = checks struct job id, that is only written at
job initialization
* progress_get_snapshot = we made it thread safe, as you might remember
* accesses struct job fields, that we protect anyways with job_mutex.
Anyways the aiocontext is not used to protect jobs fields.
- job_query_single: same as block_job_query, calls progress_get_snapshot
and accesses job fields.
So yes, I am positive that here removing the aiocontext lock does not
break anything.
Thank you,
Emanuele
