Hi, Peter,
On 2023/3/8 下午11:46, Peter Xu wrote:
1. squash fix into patch1 of yours.
2. introduce address_space_to_flatview_rcu()
3. add specific comment to define when to use which as_to_flat()
This can be together with 2).
We should suggest using address_space_to_flatview() by default in the
comment, and only use _rcu() with cautions e.g. we can mention commit()
hooks as example, and also mention the possibility of seeing very old (or
purely empty flatview) if during vm load. In that sense this can be the
last patch of your set so there's the vm load context to reference.
I hope there'll be no outliers that takes only RCU (no bql) but still
expect a very new flatview then it'll crash easily if called in a vm load.
But let's see.. I assume your test cases are already a much larger set so
covers a lot of code paths already.
4. Does enforce commit() need further modification or keep current status?
Looks like you have some new thoughts on it?
I don't.
PS: I do have some thoughts but I don't think I mentioned them.. My
thoughts were that we can actually avoid calling begin()/commit()/... hooks
during a nested do_commit() at all but only update current_map. That'll
further avoid the _rcu() patch to be introduced, but I think that needs
more changes and may not be necessary at all. Ignore this.
Got it.
Are there any other missing points?
No from my side.
Note that 8.0 reached soft freeze. Sorry to say so, but it seems this work
will only be possible (if no further objections coming) for 8.1 merge
windows, so the early merge will be after middle of Apirl. Thanks for
being consistent with it already so far.
I also want to thank you for your long-term guidance and suggestions for
this series.
To tell the truth, as a new comer, this is the first patch I try to send
to the community. Your active discussion in the emails makes me feel that
I am doing something really meaningful, so I am willing to continuously devote
my energy to participate in the discussion, and at the same time, I benefit
a lot from the discussion with you.
Thanks!
