In order to give guests a hint at whether their vCPU-s are currently
scheduled (so they can e.g. adapt their behavior in spin loops), update
the run state area (if registered) also when de-scheduling a vCPU.
Also fix an oversight in the compat mode implementation of
VCPUOP_register_runstate_memory_area.
Please also consider for the 3.4 and 3.3 branches.
Signed-off-by: Jan Beulich <jbeulich@xxxxxxxxxx>
--- 2009-08-18.orig/xen/arch/x86/domain.c 2009-08-17 11:37:44.000000000
+0200
+++ 2009-08-18/xen/arch/x86/domain.c 2009-08-18 14:18:08.000000000 +0200
@@ -1265,6 +1265,26 @@ static void paravirt_ctxt_switch_to(stru
}
}
+/* Update per-VCPU guest runstate shared memory area (if registered). */
+static void update_runstate_area(struct vcpu *v)
+{
+ if ( guest_handle_is_null(runstate_guest(v)) )
+ return;
+
+#ifdef CONFIG_COMPAT
+ if ( is_pv_32on64_domain(v->domain) )
+ {
+ struct compat_vcpu_runstate_info info;
+
+ XLAT_vcpu_runstate_info(&info, &v->runstate);
+ __copy_to_guest(v->runstate_guest.compat, &info, 1);
+ return;
+ }
+#endif
+
+ __copy_to_guest(runstate_guest(v), &v->runstate, 1);
+}
+
static inline int need_full_gdt(struct vcpu *v)
{
return (!is_hvm_vcpu(v) && !is_idle_vcpu(v));
@@ -1356,6 +1376,9 @@ void context_switch(struct vcpu *prev, s
flush_tlb_mask(&dirty_mask);
}
+ if (prev != next)
+ update_runstate_area(prev);
+
if ( is_hvm_vcpu(prev) && !list_empty(&prev->arch.hvm_vcpu.tm_list) )
pt_save_timer(prev);
@@ -1395,21 +1418,8 @@ void context_switch(struct vcpu *prev, s
context_saved(prev);
- /* Update per-VCPU guest runstate shared memory area (if registered). */
- if ( !guest_handle_is_null(runstate_guest(next)) )
- {
- if ( !is_pv_32on64_domain(next->domain) )
- __copy_to_guest(runstate_guest(next), &next->runstate, 1);
-#ifdef CONFIG_COMPAT
- else
- {
- struct compat_vcpu_runstate_info info;
-
- XLAT_vcpu_runstate_info(&info, &next->runstate);
- __copy_to_guest(next->runstate_guest.compat, &info, 1);
- }
-#endif
- }
+ if (prev != next)
+ update_runstate_area(next);
schedule_tail(next);
BUG();
--- 2009-08-18.orig/xen/arch/x86/x86_64/domain.c 2008-05-13
11:02:22.000000000 +0200
+++ 2009-08-18/xen/arch/x86/x86_64/domain.c 2009-08-18 14:18:08.000000000
+0200
@@ -56,7 +56,7 @@ arch_compat_vcpu_op(
struct vcpu_runstate_info runstate;
vcpu_runstate_get(v, &runstate);
- XLAT_vcpu_runstate_info(&info, &v->runstate);
+ XLAT_vcpu_runstate_info(&info, &runstate);
}
__copy_to_guest(v->runstate_guest.compat, &info, 1);
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
|
Home