On Wed, Feb 19, 2020 at 01:59:51PM +0100, Jan Beulich wrote: > On 13.02.2020 12:32, Roger Pau Monne wrote: > > Don't allow cpu_hotplug_begin to fail by converting the trylock into a > > blocking lock acquisition. Write users of the cpu_add_remove_lock are > > limited to CPU plug/unplug operations, and cannot deadlock between > > themselves or other users taking the lock in read mode as > > cpu_add_remove_lock is always locked with interrupts enabled. There > > are also no other locks taken during the plug/unplug operations. > > I don't think the goal was deadlock avoidance, but rather limiting > of the time spent spinning while trying to acquire the lock, in > favor of having the caller retry.
Now that the contention between read-only users is reduced as those can take the lock in parallel I think it's safe to switch writers to blocking mode. Thanks, Roger. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel