From: Aristeu Rozanski Date: Thu, 14 Aug 2008 20:32:15 +0000 (-0400) Subject: x86, perfctr: don't use CCCR_OVF_PMI1 on Pentium 4Ds X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=dcc984166870150709f0c645b521a47becd9a047;p=deliverable%2Flinux.git x86, perfctr: don't use CCCR_OVF_PMI1 on Pentium 4Ds Currently, setup_p4_watchdog() use CCCR_OVF_PMI1 to enable the counter overflow interrupts to the second logical core. But this bit doesn't work on Pentium 4 Ds (model 4, stepping 4) and this patch avoids its use on these processors. Tested on 4 different machines that have this specific model with success. Signed-off-by: Aristeu Rozanski Cc: jvillalovos@redhat.com Signed-off-by: Ingo Molnar --- diff --git a/arch/x86/kernel/cpu/perfctr-watchdog.c b/arch/x86/kernel/cpu/perfctr-watchdog.c index de7439f82b92..05cc22dbd4ff 100644 --- a/arch/x86/kernel/cpu/perfctr-watchdog.c +++ b/arch/x86/kernel/cpu/perfctr-watchdog.c @@ -478,7 +478,13 @@ static int setup_p4_watchdog(unsigned nmi_hz) perfctr_msr = MSR_P4_IQ_PERFCTR1; evntsel_msr = MSR_P4_CRU_ESCR0; cccr_msr = MSR_P4_IQ_CCCR1; - cccr_val = P4_CCCR_OVF_PMI1 | P4_CCCR_ESCR_SELECT(4); + + /* Pentium 4 D processors don't support P4_CCCR_OVF_PMI1 */ + if (boot_cpu_data.x86_model == 4 && boot_cpu_data.x86_mask == 4) + cccr_val = P4_CCCR_OVF_PMI0; + else + cccr_val = P4_CCCR_OVF_PMI1; + cccr_val |= P4_CCCR_ESCR_SELECT(4); } evntsel = P4_ESCR_EVENT_SELECT(0x3F)