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Diffstat (limited to 'arch/x86/oprofile/nmi_int.c')
-rw-r--r--arch/x86/oprofile/nmi_int.c199
1 files changed, 123 insertions, 76 deletions
diff --git a/arch/x86/oprofile/nmi_int.c b/arch/x86/oprofile/nmi_int.c
index 2c505ee..b28d2f1 100644
--- a/arch/x86/oprofile/nmi_int.c
+++ b/arch/x86/oprofile/nmi_int.c
@@ -31,8 +31,9 @@ static struct op_x86_model_spec *model;
static DEFINE_PER_CPU(struct op_msrs, cpu_msrs);
static DEFINE_PER_CPU(unsigned long, saved_lvtpc);
-/* 0 == registered but off, 1 == registered and on */
-static int nmi_enabled = 0;
+/* must be protected with get_online_cpus()/put_online_cpus(): */
+static int nmi_enabled;
+static int ctr_running;
struct op_counter_config counter_config[OP_MAX_COUNTER];
@@ -61,12 +62,16 @@ static int profile_exceptions_notify(struct notifier_block *self,
{
struct die_args *args = (struct die_args *)data;
int ret = NOTIFY_DONE;
- int cpu = smp_processor_id();
switch (val) {
case DIE_NMI:
case DIE_NMI_IPI:
- model->check_ctrs(args->regs, &per_cpu(cpu_msrs, cpu));
+ if (ctr_running)
+ model->check_ctrs(args->regs, &__get_cpu_var(cpu_msrs));
+ else if (!nmi_enabled)
+ break;
+ else
+ model->stop(&__get_cpu_var(cpu_msrs));
ret = NOTIFY_STOP;
break;
default:
@@ -95,24 +100,36 @@ static void nmi_cpu_save_registers(struct op_msrs *msrs)
static void nmi_cpu_start(void *dummy)
{
struct op_msrs const *msrs = &__get_cpu_var(cpu_msrs);
- model->start(msrs);
+ if (!msrs->controls)
+ WARN_ON_ONCE(1);
+ else
+ model->start(msrs);
}
static int nmi_start(void)
{
+ get_online_cpus();
on_each_cpu(nmi_cpu_start, NULL, 1);
+ ctr_running = 1;
+ put_online_cpus();
return 0;
}
static void nmi_cpu_stop(void *dummy)
{
struct op_msrs const *msrs = &__get_cpu_var(cpu_msrs);
- model->stop(msrs);
+ if (!msrs->controls)
+ WARN_ON_ONCE(1);
+ else
+ model->stop(msrs);
}
static void nmi_stop(void)
{
+ get_online_cpus();
on_each_cpu(nmi_cpu_stop, NULL, 1);
+ ctr_running = 0;
+ put_online_cpus();
}
#ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
@@ -252,7 +269,10 @@ static int nmi_switch_event(void)
if (nmi_multiplex_on() < 0)
return -EINVAL; /* not necessary */
- on_each_cpu(nmi_cpu_switch, NULL, 1);
+ get_online_cpus();
+ if (ctr_running)
+ on_each_cpu(nmi_cpu_switch, NULL, 1);
+ put_online_cpus();
return 0;
}
@@ -295,6 +315,7 @@ static void free_msrs(void)
kfree(per_cpu(cpu_msrs, i).controls);
per_cpu(cpu_msrs, i).controls = NULL;
}
+ nmi_shutdown_mux();
}
static int allocate_msrs(void)
@@ -307,14 +328,21 @@ static int allocate_msrs(void)
per_cpu(cpu_msrs, i).counters = kzalloc(counters_size,
GFP_KERNEL);
if (!per_cpu(cpu_msrs, i).counters)
- return 0;
+ goto fail;
per_cpu(cpu_msrs, i).controls = kzalloc(controls_size,
GFP_KERNEL);
if (!per_cpu(cpu_msrs, i).controls)
- return 0;
+ goto fail;
}
+ if (!nmi_setup_mux())
+ goto fail;
+
return 1;
+
+fail:
+ free_msrs();
+ return 0;
}
static void nmi_cpu_setup(void *dummy)
@@ -336,49 +364,6 @@ static struct notifier_block profile_exceptions_nb = {
.priority = 2
};
-static int nmi_setup(void)
-{
- int err = 0;
- int cpu;
-
- if (!allocate_msrs())
- err = -ENOMEM;
- else if (!nmi_setup_mux())
- err = -ENOMEM;
- else
- err = register_die_notifier(&profile_exceptions_nb);
-
- if (err) {
- free_msrs();
- nmi_shutdown_mux();
- return err;
- }
-
- /* We need to serialize save and setup for HT because the subset
- * of msrs are distinct for save and setup operations
- */
-
- /* Assume saved/restored counters are the same on all CPUs */
- model->fill_in_addresses(&per_cpu(cpu_msrs, 0));
- for_each_possible_cpu(cpu) {
- if (!cpu)
- continue;
-
- memcpy(per_cpu(cpu_msrs, cpu).counters,
- per_cpu(cpu_msrs, 0).counters,
- sizeof(struct op_msr) * model->num_counters);
-
- memcpy(per_cpu(cpu_msrs, cpu).controls,
- per_cpu(cpu_msrs, 0).controls,
- sizeof(struct op_msr) * model->num_controls);
-
- mux_clone(cpu);
- }
- on_each_cpu(nmi_cpu_setup, NULL, 1);
- nmi_enabled = 1;
- return 0;
-}
-
static void nmi_cpu_restore_registers(struct op_msrs *msrs)
{
struct op_msr *counters = msrs->counters;
@@ -412,20 +397,24 @@ static void nmi_cpu_shutdown(void *dummy)
apic_write(APIC_LVTPC, per_cpu(saved_lvtpc, cpu));
apic_write(APIC_LVTERR, v);
nmi_cpu_restore_registers(msrs);
+ if (model->cpu_down)
+ model->cpu_down();
}
-static void nmi_shutdown(void)
+static void nmi_cpu_up(void *dummy)
{
- struct op_msrs *msrs;
+ if (nmi_enabled)
+ nmi_cpu_setup(dummy);
+ if (ctr_running)
+ nmi_cpu_start(dummy);
+}
- nmi_enabled = 0;
- on_each_cpu(nmi_cpu_shutdown, NULL, 1);
- unregister_die_notifier(&profile_exceptions_nb);
- nmi_shutdown_mux();
- msrs = &get_cpu_var(cpu_msrs);
- model->shutdown(msrs);
- free_msrs();
- put_cpu_var(cpu_msrs);
+static void nmi_cpu_down(void *dummy)
+{
+ if (ctr_running)
+ nmi_cpu_stop(dummy);
+ if (nmi_enabled)
+ nmi_cpu_shutdown(dummy);
}
static int nmi_create_files(struct super_block *sb, struct dentry *root)
@@ -457,7 +446,6 @@ static int nmi_create_files(struct super_block *sb, struct dentry *root)
return 0;
}
-#ifdef CONFIG_SMP
static int oprofile_cpu_notifier(struct notifier_block *b, unsigned long action,
void *data)
{
@@ -465,10 +453,10 @@ static int oprofile_cpu_notifier(struct notifier_block *b, unsigned long action,
switch (action) {
case CPU_DOWN_FAILED:
case CPU_ONLINE:
- smp_call_function_single(cpu, nmi_cpu_start, NULL, 0);
+ smp_call_function_single(cpu, nmi_cpu_up, NULL, 0);
break;
case CPU_DOWN_PREPARE:
- smp_call_function_single(cpu, nmi_cpu_stop, NULL, 1);
+ smp_call_function_single(cpu, nmi_cpu_down, NULL, 1);
break;
}
return NOTIFY_DONE;
@@ -477,7 +465,75 @@ static int oprofile_cpu_notifier(struct notifier_block *b, unsigned long action,
static struct notifier_block oprofile_cpu_nb = {
.notifier_call = oprofile_cpu_notifier
};
-#endif
+
+static int nmi_setup(void)
+{
+ int err = 0;
+ int cpu;
+
+ if (!allocate_msrs())
+ return -ENOMEM;
+
+ /* We need to serialize save and setup for HT because the subset
+ * of msrs are distinct for save and setup operations
+ */
+
+ /* Assume saved/restored counters are the same on all CPUs */
+ err = model->fill_in_addresses(&per_cpu(cpu_msrs, 0));
+ if (err)
+ goto fail;
+
+ for_each_possible_cpu(cpu) {
+ if (!cpu)
+ continue;
+
+ memcpy(per_cpu(cpu_msrs, cpu).counters,
+ per_cpu(cpu_msrs, 0).counters,
+ sizeof(struct op_msr) * model->num_counters);
+
+ memcpy(per_cpu(cpu_msrs, cpu).controls,
+ per_cpu(cpu_msrs, 0).controls,
+ sizeof(struct op_msr) * model->num_controls);
+
+ mux_clone(cpu);
+ }
+
+ nmi_enabled = 0;
+ ctr_running = 0;
+ barrier();
+ err = register_die_notifier(&profile_exceptions_nb);
+ if (err)
+ goto fail;
+
+ get_online_cpus();
+ register_cpu_notifier(&oprofile_cpu_nb);
+ on_each_cpu(nmi_cpu_setup, NULL, 1);
+ nmi_enabled = 1;
+ put_online_cpus();
+
+ return 0;
+fail:
+ free_msrs();
+ return err;
+}
+
+static void nmi_shutdown(void)
+{
+ struct op_msrs *msrs;
+
+ get_online_cpus();
+ unregister_cpu_notifier(&oprofile_cpu_nb);
+ on_each_cpu(nmi_cpu_shutdown, NULL, 1);
+ nmi_enabled = 0;
+ ctr_running = 0;
+ put_online_cpus();
+ barrier();
+ unregister_die_notifier(&profile_exceptions_nb);
+ msrs = &get_cpu_var(cpu_msrs);
+ model->shutdown(msrs);
+ free_msrs();
+ put_cpu_var(cpu_msrs);
+}
#ifdef CONFIG_PM
@@ -687,9 +743,6 @@ int __init op_nmi_init(struct oprofile_operations *ops)
return -ENODEV;
}
-#ifdef CONFIG_SMP
- register_cpu_notifier(&oprofile_cpu_nb);
-#endif
/* default values, can be overwritten by model */
ops->create_files = nmi_create_files;
ops->setup = nmi_setup;
@@ -716,12 +769,6 @@ int __init op_nmi_init(struct oprofile_operations *ops)
void op_nmi_exit(void)
{
- if (using_nmi) {
+ if (using_nmi)
exit_sysfs();
-#ifdef CONFIG_SMP
- unregister_cpu_notifier(&oprofile_cpu_nb);
-#endif
- }
- if (model->exit)
- model->exit();
}
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