Hi,
  When I modprobe oprofile in domain0, the dmesg show below:
    [root@sd02138 ~]# dmesg | tail -n 3
   sha256_ssse3: Using SSSE3 optimized SHA-256 implementation
   SELinux: initialized (dev cifs, type cifs), uses genfs_contexts
   oprofile: using timer interrupt.
  But in domainU it the oprofile using the NMI interrup rightly.
 [root@Domain1 ~]# modprobe oprofile 
 [root@Domain1 ~]# dmesg | tail -n 3
 CIFS VFS: default security mechanism requested. The default security mechanism will be upgraded from ntlm to ntlmv2 in kernel release 3.3
 SELinux: initialized (dev cifs, type cifs), uses genfs_contexts
 oprofile: using NMI interrupt.


 I have patch the oprofile correctly,the opcontrol show:
[root@sd02138 ~]# opcontrol
……
--xen=file Xen image (for Xen only) 
--active-domains=id[,ids] list of domains in multiple domain profiling session (Xen)
(detailed profiling of user level and kernel modules code)
(requires running oprofile on these domains)
--passive-domains=id[,ids] list of domains to be profiled (Xen).
or --domains=id[,ids] (coarse profiling of user level and kernel modules code)
(no need to run oprofile on these domains)
--passive-images=file[,files] list of kernel images associated with each passive domain
or
--domain-images=file[,files]ll patch the oprofile correctly,the opcontrol show:

cpu flags showed the apic flag
[root@sd02138 ~]# cat /proc/cpuinfo | grep flags
flags : fpu de tsc msr pae mce cx8 apic sep mca cmov pat clflush acpi mmx fxsr sse sse2 ss ht syscall nx lm constant_tsc rep_good nopl nonstop_tsc pni pclmulqdq monitor est ssse3 cx16 sse4_1 sse4_2 popcnt aes hypervisor lahf_lm arat epb dtherm

Does xenoprof does not supprot X86_64? 
zyy9812@126.com