diff options
Diffstat (limited to 'arch/x86/oprofile/nmi_int.c')
| -rw-r--r-- | arch/x86/oprofile/nmi_int.c | 100 |
1 files changed, 92 insertions, 8 deletions
diff --git a/arch/x86/oprofile/nmi_int.c b/arch/x86/oprofile/nmi_int.c index 287513a0981..2a65fe7680a 100644 --- a/arch/x86/oprofile/nmi_int.c +++ b/arch/x86/oprofile/nmi_int.c @@ -23,12 +23,18 @@ #include "op_counter.h" #include "op_x86_model.h" +DEFINE_PER_CPU(int, switch_index); + static struct op_x86_model_spec const *model; static DEFINE_PER_CPU(struct op_msrs, cpu_msrs); static DEFINE_PER_CPU(unsigned long, saved_lvtpc); static int nmi_start(void); static void nmi_stop(void); +static void nmi_cpu_save_mpx_registers(struct op_msrs *msrs); +static void nmi_cpu_restore_mpx_registers(struct op_msrs *msrs); +static void nmi_cpu_stop(void *dummy); +static void nmi_cpu_start(void *dummy); /* 0 == registered but off, 1 == registered and on */ static int nmi_enabled = 0; @@ -81,6 +87,47 @@ static void exit_sysfs(void) #define exit_sysfs() do { } while (0) #endif /* CONFIG_PM */ +static void nmi_cpu_switch(void *dummy) +{ + int cpu = smp_processor_id(); + int si = per_cpu(switch_index, cpu); + struct op_msrs *msrs = &per_cpu(cpu_msrs, cpu); + + nmi_cpu_stop(NULL); + nmi_cpu_save_mpx_registers(msrs); + + /* move to next set */ + si += model->num_hardware_counters; + if ((si > model->num_counters) || (counter_config[si].count == 0)) + per_cpu(switch_index, smp_processor_id()) = 0; + else + per_cpu(switch_index, smp_processor_id()) = si; + + nmi_cpu_restore_mpx_registers(msrs); + model->setup_ctrs(msrs); + nmi_cpu_start(NULL); +} + +/* + * Quick check to see if multiplexing is necessary. + * The check should be sufficient since counters are used + * in ordre. + */ +static int nmi_multiplex_on(void) +{ + return counter_config[model->num_hardware_counters].count ? 0 : -EINVAL; +} + +static int nmi_switch_event(void) +{ + if (nmi_multiplex_on() < 0) + return -EINVAL; + + on_each_cpu(nmi_cpu_switch, NULL, 0, 1); + + return 0; +} + static int profile_exceptions_notify(struct notifier_block *self, unsigned long val, void *data) { @@ -144,11 +191,10 @@ static void free_msrs(void) static int allocate_msrs(void) { - int success = 1; + int i, success = 1; size_t controls_size = sizeof(struct op_msr) * model->num_controls; size_t counters_size = sizeof(struct op_msr) * model->num_counters; - int i; for_each_possible_cpu(i) { per_cpu(cpu_msrs, i).counters = kmalloc(counters_size, GFP_KERNEL); @@ -156,8 +202,8 @@ static int allocate_msrs(void) success = 0; break; } - per_cpu(cpu_msrs, i).controls = kmalloc(controls_size, - GFP_KERNEL); + per_cpu(cpu_msrs, i).controls = + kmalloc(controls_size, GFP_KERNEL); if (!per_cpu(cpu_msrs, i).controls) { success = 0; break; @@ -201,7 +247,8 @@ static int nmi_setup(void) return err; } - /* We need to serialize save and setup for HT because the subset + /* + * We need to serialize save and setup for HT because the subset * of msrs are distinct for save and setup operations */ @@ -217,7 +264,6 @@ static int nmi_setup(void) per_cpu(cpu_msrs, 0).controls, sizeof(struct op_msr) * model->num_controls); } - } on_each_cpu(nmi_save_registers, NULL, 1); on_each_cpu(nmi_cpu_setup, NULL, 1); @@ -225,7 +271,41 @@ static int nmi_setup(void) return 0; } -static void nmi_restore_registers(struct op_msrs *msrs) +static void nmi_cpu_save_mpx_registers(struct op_msrs *msrs) +{ + unsigned int si = __get_cpu_var(switch_index); + unsigned int const nr_ctrs = model->num_hardware_counters; + struct op_msr *counters = &msrs->counters[si]; + unsigned int i; + + for (i = 0; i < nr_ctrs; ++i) { + int offset = i + si; + if (counters[offset].addr) { + rdmsr(counters[offset].addr, + counters[offset].multiplex.low, + counters[offset].multiplex.high); + } + } +} + +static void nmi_cpu_restore_mpx_registers(struct op_msrs *msrs) +{ + unsigned int si = __get_cpu_var(switch_index); + unsigned int const nr_ctrs = model->num_hardware_counters; + struct op_msr *counters = &msrs->counters[si]; + unsigned int i; + + for (i = 0; i < nr_ctrs; ++i) { + int offset = i + si; + if (counters[offset].addr) { + wrmsr(counters[offset].addr, + counters[offset].multiplex.low, + counters[offset].multiplex.high); + } + } +} + +static void nmi_cpu_restore_registers(struct op_msrs *msrs) { unsigned int const nr_ctrs = model->num_counters; unsigned int const nr_ctrls = model->num_controls; @@ -265,7 +345,8 @@ static void nmi_cpu_shutdown(void *dummy) apic_write(APIC_LVTERR, v | APIC_LVT_MASKED); apic_write(APIC_LVTPC, per_cpu(saved_lvtpc, cpu)); apic_write(APIC_LVTERR, v); - nmi_restore_registers(msrs); + nmi_cpu_restore_registers(msrs); + __get_cpu_var(switch_index) = 0; } static void nmi_shutdown(void) @@ -328,6 +409,7 @@ static int nmi_create_files(struct super_block *sb, struct dentry *root) oprofilefs_create_ulong(sb, dir, "unit_mask", &counter_config[i].unit_mask); oprofilefs_create_ulong(sb, dir, "kernel", &counter_config[i].kernel); oprofilefs_create_ulong(sb, dir, "user", &counter_config[i].user); + counter_config[i].save_count_low = 0; } return 0; @@ -469,12 +551,14 @@ int __init op_nmi_init(struct oprofile_operations *ops) } /* default values, can be overwritten by model */ + __get_cpu_var(switch_index) = 0; ops->create_files = nmi_create_files; ops->setup = nmi_setup; ops->shutdown = nmi_shutdown; ops->start = nmi_start; ops->stop = nmi_stop; ops->cpu_type = cpu_type; + ops->switch_events = nmi_switch_event; if (model->init) ret = model->init(ops); |