On 01.02.24 11:21, Kevin Wolf wrote:
Am 01.02.2024 um 10:43 hat Hanna Czenczek geschrieben:
On 31.01.24 11:17, Kevin Wolf wrote:
Am 29.01.2024 um 17:30 hat Hanna Czenczek geschrieben:
I don’t like using drain as a form of lock specifically against AioContext
changes, but maybe Stefan is right, and we should use it in this specific
case to get just the single problem fixed. (Though it’s not quite trivial
either. We’d probably still want to remove the assertion from
blk_get_aio_context(), so we don’t have to require all of its callers to
hold a count in the in-flight counter.)
Okay, fair, maybe fixing the specific problem is more important that
solving the more generic blk_get_aio_context() race.
In this case, wouldn't it be enough to increase the in-flight counter so
that the drain before switching AioContexts would run the BH before
anything bad can happen? Does the following work?
Yes, that’s what I had in mind (Stefan, too, I think), and in testing,
it looks good.
Oh, sorry, I completely misunderstood then. I thought you were talking
about adding a new drained section somewhere and that sounded a bit more
complicated. :-)
If it works, let's do this. Would you like to pick this up and send it
as a formal patch (possibly in a more polished form), or should I do
that?
Sure, I can do it.
Hanna
