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Further > > work should be done in order to re-add more fine grained locking to > > the domain destruction path once a proper solution to avoid the > > heap_lock contention is found. > > --- > ... > > Since this is a revert and not new code I think the risk is lower. > > There's however some risk, as the original commit was from 2017, and > > hence the surrounding code has changed a bit. It's also a possibility > > that some other parts of the domain destruction code now rely on this > > more fine grained locking. Local tests however haven't shown issues. > > From a release management point of view I don't regard this as the > kind of "revert" that ought to get any kind of special consideration. > The tree has been like this since 2017 and Xen 4.11 and many changes > have been happened since. > > So I am going to treat this as an effectively new change. > > AIUI it is a proposal to improve performance, not a bugfix. Was this > change posted (or, proposed on-list) before the Xen 4.16 Last Posting > Date (24th of September) ? Even if it was, it would need a freeze > exception. It was posted here: https://lore.kernel.org/xen-devel/de46590ad566d9be55b26eaca0bc4dc7fbbada59.1585063311.git.hongyxia@amazon.com/ Which was missing a spin_barrier, and in a different form here: https://lore.kernel.org/xen-devel/2e7044de3cd8a6768a20250e61fe262f3a018724.1631790362.git.isaikin-dmitry@yandex.ru/ Thanks, Roger.