How did you tested this ? I am curious if you tried massively-parallel mkdir/rmdir for the same name. Perhaps try to ask Peter Holm to test this.

This is a bit hacky, even for my standards, so I've come up with this as an alternative: https://reviews.freebsd.org/D20411.

P_TRACED is always set or cleared with proctree_lock exclusively locked, except at the process exit. After that, the process lock in exit1() is dropped and we acquire the proctree_lock. PRS_ZOMBIE is set much later on the process.

Fix style.

I'm satisfied with the way this code looks. It will take approval from someone more senior on the project before I can check it in. You might want to provide some demonstration of performance improvement - that kind of demonstration is necessary for approval from some folks.

Thanks!

Fix locking.

Looks good to me.

I don't have any exceptionally helpful comments; the code looks fine, but I haven't given it the review it deserves.

• Fix after bogus rebase

• Rebase after rP502585

In D20394#440452, @antoine wrote:

A few questions:

• there are 0 integrity check for os ports, while all non-os ports do check the SHA-256 of their distfiles, is this intended?

Other than word-smithing the comments, I like it.

I've now tried doing this and have finally managed to get it to work. A couple of things: