[Xen-devel] [PATCH] Fix xenoprof counter overflow check

[Niraj Tolia <ntolia@xxxxxxxxx>]

# HG changeset patch
# User Niraj Tolia <ntolia@xxxxxxxxx>
# Date 1231217146 28800
# Node ID eb1ad7bbdaf3ae553a6bf319180b5880f5ac4307
# Parent  8417ddc981b407753f966c568ef8c7b673d8d22a
Xenoprof patch to fix the counter overflow check for CPUs with counter
width > 32

I had to port this patch from mainline Linux where it can be found at
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=7c64ade53a6f977d73f16243865c42ceae999aea

Signed-off-by: Niraj Tolia <ntolia@xxxxxxxxx>

diff -r 8417ddc981b4 -r eb1ad7bbdaf3 xen/arch/x86/oprofile/op_model_ppro.c
--- a/xen/arch/x86/oprofile/op_model_ppro.c     Mon Jan 05 11:10:54 2009 +0000
+++ b/xen/arch/x86/oprofile/op_model_ppro.c     Mon Jan 05 20:45:46 2009 -0800
@@ -25,9 +25,8 @@
 #define NUM_COUNTERS 2
 #define NUM_CONTROLS 2
 
-#define CTR_READ(l,h,msrs,c) do {rdmsr(msrs->counters[(c)].addr, (l), (h));} 
while (0)
 #define CTR_WRITE(l,msrs,c) do {wrmsr(msrs->counters[(c)].addr, -(u32)(l), 
-1);} while (0)
-#define CTR_OVERFLOWED(n) (!((n) & (1U<<31)))
+#define CTR_OVERFLOWED(n) (!((n) & (1ULL<<31)))
 
 #define CTRL_READ(l,h,msrs,c) do {rdmsr((msrs->controls[(c)].addr), (l), 
(h));} while (0)
 #define CTRL_WRITE(l,h,msrs,c) do {wrmsr((msrs->controls[(c)].addr), (l), 
(h));} while (0)
@@ -98,7 +97,7 @@ static int ppro_check_ctrs(unsigned int 
                            struct op_msrs const * const msrs,
                            struct cpu_user_regs * const regs)
 {
-       unsigned int low, high;
+       u64 val;
        int i;
        int ovf = 0;
        unsigned long eip = regs->eip;
@@ -107,8 +106,8 @@ static int ppro_check_ctrs(unsigned int 
        for (i = 0 ; i < NUM_COUNTERS; ++i) {
                if (!reset_value[i])
                        continue;
-               CTR_READ(low, high, msrs, i);
-               if (CTR_OVERFLOWED(low)) {
+               rdmsrl(msrs->counters[i].addr, val);
+               if (CTR_OVERFLOWED(val)) {
                        xenoprof_log_event(current, regs, eip, mode, i);
                        CTR_WRITE(reset_value[i], msrs, i);
                        ovf = 1;

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel