static void p4_check_ctrs(unsigned int const cpu, struct op_msrs const * const msrs, struct pt_regs * const regs) { unsigned long ctr, low, high, stag, real; int i; stag = get_stagger(); for (i = 0; i < num_counters; ++i) { if (!sysctl.ctr[i].enabled) continue; real = VIRT_CTR(stag, i); CCCR_READ(low, high, real); CTR_READ(ctr, high, real); if (CCCR_OVF_P(low) || CTR_OVERFLOW_P(ctr)) { op_do_profile(cpu, instruction_pointer(regs), IRQ_ENABLED(regs), i); CTR_WRITE(oprof_data[cpu].ctr_count[i], real); CCCR_CLEAR_OVF(low); CCCR_WRITE(low, high, real); CTR_WRITE(oprof_data[cpu].ctr_count[i], real); } } apic_write(APIC_LVTPC, apic_read(APIC_LVTPC) & ~APIC_LVT_MASKED); }
static int p4_check_ctrs(unsigned int const cpu, struct op_msrs const * const msrs, struct pt_regs * const regs) { unsigned long ctr, low, high, stag, real; int i; unsigned long eip = instruction_pointer(regs); int is_kernel = !user_mode(regs); stag = get_stagger(); for (i = 0; i < num_counters; ++i) { if (!counter_config[i].event) continue; /* * there is some eccentricity in the hardware which * requires that we perform 2 extra corrections: * * - check both the CCCR:OVF flag for overflow and the * counter high bit for un-flagged overflows. * * - write the counter back twice to ensure it gets * updated properly. * * the former seems to be related to extra NMIs happening * during the current NMI; the latter is reported as errata * N15 in intel doc 249199-029, pentium 4 specification * update, though their suggested work-around does not * appear to solve the problem. */ real = VIRT_CTR(stag, i); CCCR_READ(low, high, real); CTR_READ(ctr, high, real); if (CCCR_OVF_P(low) || CTR_OVERFLOW_P(ctr)) { oprofile_add_sample(eip, is_kernel, i, cpu); CTR_WRITE(reset_value[i], real); CCCR_CLEAR_OVF(low); CCCR_WRITE(low, high, real); CTR_WRITE(reset_value[i], real); /* P4 quirk: you have to re-unmask the apic vector */ apic_write(APIC_LVTPC, apic_read(APIC_LVTPC) & ~APIC_LVT_MASKED); } } /* P4 quirk: you have to re-unmask the apic vector */ apic_write(APIC_LVTPC, apic_read(APIC_LVTPC) & ~APIC_LVT_MASKED); /* See op_model_ppro.c */ return 1; }