macOS 10.15 introduced the more efficient hv_vcpu_run_until() function
to supersede hv_vcpu_run(). According to the documentation, there is no
longer any reason to use the latter on modern host OS versions, especially
after 11.0 added support for an indefinite deadline.
Observed behaviour of the newer function is that as documented, it exits
much less frequently - and most of the original function’s exits seem to
have been effectively pointless.
Another reason to use the new function is that it is a prerequisite for
using newer features such as in-kernel APIC support. (Not covered by
this patch.)
This change implements the upgrade by selecting one of three code paths
at compile time: two static code paths for the new and old functions
respectively, when building for targets where the new function is either
not available, or where the built executable won’t run on older
platforms lacking the new function anyway. The third code path selects
dynamically based on runtime detected availability of the weakly-linked
symbol.
Signed-off-by: Phil Dennis-Jordan <phil@philjordan.eu>
Message-ID: <20240605112556.43193-7-phil@philjordan.eu>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
a59f5b2f83