Fix the UMA reclaim worker

[markj]

Summary

atomic_set_* ORs its arguments together, but the intention here was
obviously to clear the flag.

[kib]

Plain store is enough, _rel does not add any functionality there. Or the load in the while() loop above should become _acq(), but I do not see a need.

[markj]

In D13412#280192, @kib wrote:

Plain store is enough, _rel does not add any functionality there. Or the load in the while() loop above should become _acq(), but I do not see a need.

Indeed, but there is no plain atomic_store_int().

[kib]

In D13412#280195, @markj wrote:

In D13412#280192, @kib wrote:

Plain store is enough, _rel does not add any functionality there. Or the load in the while() loop above should become _acq(), but I do not see a need.

Indeed, but there is no plain atomic_store_int().

Plain assignment to volatile does it. Explanation was added to atomic(9) not too long time ago.

[markj]

• Use a plain store to the volatile uma_reclaim_needed.