@@ -319,8 +319,6 @@ static void setup_p6_watchdog(unsigned counter)
{
unsigned int evntsel;
- nmi_perfctr_msr = MSR_P6_PERFCTR(0);
-
if ( !nmi_p6_event_width && current_cpu_data.cpuid_level >= 0xa )
nmi_p6_event_width = MASK_EXTR(cpuid_eax(0xa), P6_EVENT_WIDTH_MASK);
if ( !nmi_p6_event_width )
@@ -330,6 +328,8 @@ static void setup_p6_watchdog(unsigned counter)
nmi_p6_event_width > BITS_PER_LONG )
return;
+ nmi_perfctr_msr = MSR_P6_PERFCTR(0);
+
clear_msr_range(MSR_P6_EVNTSEL(0), 2);
clear_msr_range(MSR_P6_PERFCTR(0), 2);
@@ -345,13 +345,13 @@ static void setup_p6_watchdog(unsigned counter)
wrmsr(MSR_P6_EVNTSEL(0), evntsel, 0);
}
-static int setup_p4_watchdog(void)
+static void setup_p4_watchdog(void)
{
uint64_t misc_enable;
rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
if (!(misc_enable & MSR_IA32_MISC_ENABLE_PERF_AVAIL))
- return 0;
+ return;
nmi_perfctr_msr = MSR_P4_IQ_PERFCTR0;
nmi_p4_cccr_val = P4_NMI_IQ_CCCR0;
@@ -374,13 +374,12 @@ static int setup_p4_watchdog(void)
clear_msr_range(0x3E0, 2);
clear_msr_range(MSR_P4_BPU_CCCR0, 18);
clear_msr_range(MSR_P4_BPU_PERFCTR0, 18);
-
+
wrmsrl(MSR_P4_CRU_ESCR0, P4_NMI_CRU_ESCR0);
wrmsrl(MSR_P4_IQ_CCCR0, P4_NMI_IQ_CCCR0 & ~P4_CCCR_ENABLE);
write_watchdog_counter("P4_IQ_COUNTER0");
apic_write(APIC_LVTPC, APIC_DM_NMI);
wrmsrl(MSR_P4_IQ_CCCR0, nmi_p4_cccr_val);
- return 1;
}
void setup_apic_nmi_watchdog(void)
@@ -395,8 +394,6 @@ void setup_apic_nmi_watchdog(void)
case 0xf ... 0x19:
setup_k7_watchdog();
break;
- default:
- return;
}
break;
case X86_VENDOR_INTEL:
@@ -407,14 +404,16 @@ void setup_apic_nmi_watchdog(void)
: CORE_EVENT_CPU_CLOCKS_NOT_HALTED);
break;
case 15:
- if (!setup_p4_watchdog())
- return;
+ setup_p4_watchdog();
break;
- default:
- return;
}
break;
- default:
+ }
+
+ if ( nmi_perfctr_msr == 0 )
+ {
+ printk(XENLOG_WARNING "Failed to configure NMI watchdog\n");
+ nmi_watchdog = NMI_NONE;
return;
}
Right now, if the user requests the watchdog on the command line, setup_apic_nmi_watchdog() will blindly assume that setting up the watchdog worked. Reuse nmi_perfctr_msr to identify when the watchdog has been set up. Rearrange setup_p6_watchdog() to not set nmi_perfctr_msr until the sanity checks are performed. Turn setup_p4_watchdog() into a void function, matching the others. If the watchdog isn't set up, inform the user and override to NMI_NONE, which will prevent check_nmi_watchdog() from claiming that all CPUs are stuck. e.g.: (XEN) alt table ffff82d040697c38 -> ffff82d0406a97f0 (XEN) Failed to configure NMI watchdog (XEN) Brought up 512 CPUs (XEN) Scheduling granularity: cpu, 1 CPU per sched-resource Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> --- CC: Jan Beulich <JBeulich@suse.com> CC: Roger Pau Monné <roger.pau@citrix.com> This is all horrible code. --- xen/arch/x86/nmi.c | 25 ++++++++++++------------- 1 file changed, 12 insertions(+), 13 deletions(-)