x86/pv: Improve dom0_update_physmap() with CONFIG_SPECULATIVE_HARDEN_BRANCH
dom0_update_physmap() is mostly called in two tight loops, where the lfences
hidden in is_pv_32bit_domain() have a substantial impact.
None of the boot time construction needs protection against malicious
speculation, so use a local variable and calculate is_pv_32bit_domain() just
once.
Reformat the some of the code for legibility, now that the volume has reduced,
and removal of some gratuitous negations.
No functional change.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
projects / xen.git / commit