Factor out a compat boolean to remove the lfence overhead from multiple
is_pv_32bit_domain() calls.
Signed-off-by: Andrew Cooper
---
CC: Jan Beulich
CC: Roger Pau Monné
CC: Wei Liu
v2:
* Reinstate the conditional for the start info pointer, in case Intel/AMD
can't be persuaded to adjust the architectural guarentees for upper bits in
compatibility mode transitions.
---
xen/arch/x86/pv/shim.c | 8
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/xen/arch/x86/pv/shim.c b/xen/arch/x86/pv/shim.c
index d16c0048c0..4c6f442274 100644
--- a/xen/arch/x86/pv/shim.c
+++ b/xen/arch/x86/pv/shim.c
@@ -280,12 +280,12 @@ void __init pv_shim_setup_dom(struct domain *d,
l4_pgentry_t *l4start,
static void write_start_info(struct domain *d)
{
struct cpu_user_regs *regs = guest_cpu_user_regs();
-start_info_t *si = map_domain_page(_mfn(is_pv_32bit_domain(d) ? regs->edx
- :
regs->rdx));
+bool compat = is_pv_32bit_domain(d);
+start_info_t *si = map_domain_page(_mfn(compat ? regs->edx : regs->rdx));
uint64_t param;
snprintf(si->magic, sizeof(si->magic), "xen-3.0-x86_%s",
- is_pv_32bit_domain(d) ? "32p" : "64");
+ compat ? "32p" : "64");
si->nr_pages = domain_tot_pages(d);
si->shared_info = virt_to_maddr(d->shared_info);
si->flags = 0;
@@ -300,7 +300,7 @@ static void write_start_info(struct domain *d)
>console.domU.mfn) )
BUG();
-if ( is_pv_32bit_domain(d) )
+if ( compat )
xlat_start_info(si, XLAT_start_info_console_domU);
unmap_domain_page(si);
--
2.11.0
