Renato
I did what you suggested. Opreport –l
showed p2m_change_type () to be one of hot functions.
This is an AMD specific function and should
not appear when running on Intel platforms.
So I did a gdb of xen-syms and the EIP for
the p2m_change_type function shows that the actual EIP is iommu_domain_destroy
p2m_change_type is 0xffff828c801771d0 è Iommu_domain_destroy
(which again should NOT be the case)
So there is something wrong with the way
oprofile is mapping the xen symbols,
The command I use is
Opcontrol --passive-domains=1 –xen=/boot/xen-sysms
–vmlinux=/boot/vmlinux –event=CPU_CLK_UNHALTED:1000000 –start
Can you please help in determining why
oprofile is getting the symbols wrong?
Thanks
-Padma
From: Santos, Jose
Renato G [mailto:joserenato.santos@xxxxxx]
Sent: Friday, March 07, 2008 8:39
AM
To: Apparao,
Padmashree K; oprofile-list@xxxxxxxxxxxxxxxxxxxxx;
xen-users@xxxxxxxxxxxxxxxxxxx
Subject: RE: oprofile 0.9.3 xen
symbols incorrect
Padma,
You will have to debug this some more and
provide more details.
I suggest that you remove the patch and do
some more tests on the original system.
Try generating a more detailed opreport
including the EIP values in addition to the symbols, and then check what symbol
the suspicious EIP corresponds to in the xen image.
Unfortunately I will not have much time to
test this myself
Good luck
Renato
From: Apparao, Padmashree K
[mailto:padmashree.k.apparao@xxxxxxxxx]
Sent: Thursday, March 06, 2008
10:05 PM
To: Santos, Jose Renato G;
oprofile-list@xxxxxxxxxxxxxxxxxxxxx; xen-users@xxxxxxxxxxxxxxxxxxx
Subject: RE: oprofile 0.9.3 xen
symbols incorrect
Renato,
OOPs that patch kills the VM that is
running L
-Padma
From: Santos, Jose
Renato G [mailto:joserenato.santos@xxxxxx]
Sent: Thursday, March 06, 2008
9:22 PM
To: Apparao,
Padmashree K; oprofile-list@xxxxxxxxxxxxxxxxxxxxx;
xen-users@xxxxxxxxxxxxxxxxxxx
Subject: RE: oprofile 0.9.3 xen
symbols incorrect
Padma,
I received some reports in the past that
Xenoprof was generating incorrect symbols for HVM guests on Intel processors.
Here is a patch provided by Andrew
Gallagher that should fix the problem but I did not have had a chance to test
it yet. It has been sitting on my todo list for a long time.
Could you please check if this fix the
problem and let me know.
Thanks
Renato
diff -r 0164d924ceba
xen/arch/x86/hvm/vmx/vmx.c
--- a/xen/arch/x86/hvm/vmx/vmx.c Wed Feb 13 10:43:13 2008 +0000
+++ b/xen/arch/x86/hvm/vmx/vmx.c Thu Mar 06 21:08:46 2008 -0800
@@ -2511,6 +2511,7 @@ asmlinkage void vmx_vmexit_handler(struc
* (2) NMI
*/
unsigned int intr_info,
vector;
+ int saved_eip;
intr_info =
__vmread(VM_EXIT_INTR_INFO);
BUG_ON(!(intr_info &
INTR_INFO_VALID_MASK));
@@ -2565,7 +2566,10 @@ asmlinkage void vmx_vmexit_handler(struc
(X86_EVENTTYPE_NMI << 8) )
goto exit_and_crash;
HVMTRACE_0D(NMI, v);
+ saved_eip =
regs->eip;
+
regs->eip = __vmread(GUEST_RIP);
do_nmi(regs); /* Real NMI, vector 2: normal processing. */
+
regs->eip = saved_eip;
break;
case TRAP_machine_check:
HVMTRACE_0D(MCE, v);
From: Apparao, Padmashree K
[mailto:padmashree.k.apparao@xxxxxxxxx]
Sent: Thursday, March 06, 2008
3:21 PM
To: oprofile-list@xxxxxxxxxxxxxxxxxxxxx;
Santos, Jose Renato G; xen-users@xxxxxxxxxxxxxxxxxxx
Subject: FW: oprofile 0.9.3 xen
symbols incorrect
Hi
I am using oprofile 0.9.3 on xen cs 16540 on an Intel
system.
When I look at the top “hot” functions, I see
p2m_change_type being one of the top function in xen-syms. This function is
only in the svm (AMD) code and should not appear on an Intel system. I see that
this function is not being clled at all when I am running my apps as I have put
printk in the functions and they do not show up anywhere in the dmesg.
Is it possible that oprofile is picking up the symbols from
elsewhere? The /root/.profile/daemonrc file shows the correct xen-syms file, so
obviously it is not using that..
(I am profiling a HVM domain using passive-domains in the
command line for opcontrol)
Thanks
-Padma
