[CPUFREQ] use dynamic debug instead of custom infrastructure
With dynamic debug having gained the capability to report debug messages
also during the boot process, it offers a far superior interface for
debug messages than the custom cpufreq infrastructure. As a first step,
remove the old cpufreq_debug_printk() function and replace it with a call
to the generic pr_debug() function.
How can dynamic debug be used on cpufreq? You need a kernel which has
CONFIG_DYNAMIC_DEBUG enabled.
To enabled debugging during runtime, mount debugfs and
$ echo -n 'module cpufreq +p' > /sys/kernel/debug/dynamic_debug/control
for debugging the complete "cpufreq" module. To achieve the same goal during
boot, append
ddebug_query="module cpufreq +p"
as a boot parameter to the kernel of your choice.
For more detailled instructions, please see
Documentation/dynamic-debug-howto.txt
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Dave Jones <davej@redhat.com>
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 7c10f96..1e08af4 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -32,9 +32,6 @@
#include <trace/events/power.h>
-#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_CORE, \
- "cpufreq-core", msg)
-
/**
* The "cpufreq driver" - the arch- or hardware-dependent low
* level driver of CPUFreq support, and its spinlock. This lock
@@ -181,93 +178,6 @@
/*********************************************************************
- * UNIFIED DEBUG HELPERS *
- *********************************************************************/
-#ifdef CONFIG_CPU_FREQ_DEBUG
-
-/* what part(s) of the CPUfreq subsystem are debugged? */
-static unsigned int debug;
-
-/* is the debug output ratelimit'ed using printk_ratelimit? User can
- * set or modify this value.
- */
-static unsigned int debug_ratelimit = 1;
-
-/* is the printk_ratelimit'ing enabled? It's enabled after a successful
- * loading of a cpufreq driver, temporarily disabled when a new policy
- * is set, and disabled upon cpufreq driver removal
- */
-static unsigned int disable_ratelimit = 1;
-static DEFINE_SPINLOCK(disable_ratelimit_lock);
-
-static void cpufreq_debug_enable_ratelimit(void)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&disable_ratelimit_lock, flags);
- if (disable_ratelimit)
- disable_ratelimit--;
- spin_unlock_irqrestore(&disable_ratelimit_lock, flags);
-}
-
-static void cpufreq_debug_disable_ratelimit(void)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&disable_ratelimit_lock, flags);
- disable_ratelimit++;
- spin_unlock_irqrestore(&disable_ratelimit_lock, flags);
-}
-
-void cpufreq_debug_printk(unsigned int type, const char *prefix,
- const char *fmt, ...)
-{
- char s[256];
- va_list args;
- unsigned int len;
- unsigned long flags;
-
- WARN_ON(!prefix);
- if (type & debug) {
- spin_lock_irqsave(&disable_ratelimit_lock, flags);
- if (!disable_ratelimit && debug_ratelimit
- && !printk_ratelimit()) {
- spin_unlock_irqrestore(&disable_ratelimit_lock, flags);
- return;
- }
- spin_unlock_irqrestore(&disable_ratelimit_lock, flags);
-
- len = snprintf(s, 256, KERN_DEBUG "%s: ", prefix);
-
- va_start(args, fmt);
- len += vsnprintf(&s[len], (256 - len), fmt, args);
- va_end(args);
-
- printk(s);
-
- WARN_ON(len < 5);
- }
-}
-EXPORT_SYMBOL(cpufreq_debug_printk);
-
-
-module_param(debug, uint, 0644);
-MODULE_PARM_DESC(debug, "CPUfreq debugging: add 1 to debug core,"
- " 2 to debug drivers, and 4 to debug governors.");
-
-module_param(debug_ratelimit, uint, 0644);
-MODULE_PARM_DESC(debug_ratelimit, "CPUfreq debugging:"
- " set to 0 to disable ratelimiting.");
-
-#else /* !CONFIG_CPU_FREQ_DEBUG */
-
-static inline void cpufreq_debug_enable_ratelimit(void) { return; }
-static inline void cpufreq_debug_disable_ratelimit(void) { return; }
-
-#endif /* CONFIG_CPU_FREQ_DEBUG */
-
-
-/*********************************************************************
* EXTERNALLY AFFECTING FREQUENCY CHANGES *
*********************************************************************/
@@ -291,7 +201,7 @@
if (!l_p_j_ref_freq) {
l_p_j_ref = loops_per_jiffy;
l_p_j_ref_freq = ci->old;
- dprintk("saving %lu as reference value for loops_per_jiffy; "
+ pr_debug("saving %lu as reference value for loops_per_jiffy; "
"freq is %u kHz\n", l_p_j_ref, l_p_j_ref_freq);
}
if ((val == CPUFREQ_PRECHANGE && ci->old < ci->new) ||
@@ -299,7 +209,7 @@
(val == CPUFREQ_RESUMECHANGE || val == CPUFREQ_SUSPENDCHANGE)) {
loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq,
ci->new);
- dprintk("scaling loops_per_jiffy to %lu "
+ pr_debug("scaling loops_per_jiffy to %lu "
"for frequency %u kHz\n", loops_per_jiffy, ci->new);
}
}
@@ -326,7 +236,7 @@
BUG_ON(irqs_disabled());
freqs->flags = cpufreq_driver->flags;
- dprintk("notification %u of frequency transition to %u kHz\n",
+ pr_debug("notification %u of frequency transition to %u kHz\n",
state, freqs->new);
policy = per_cpu(cpufreq_cpu_data, freqs->cpu);
@@ -340,7 +250,7 @@
if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) {
if ((policy) && (policy->cpu == freqs->cpu) &&
(policy->cur) && (policy->cur != freqs->old)) {
- dprintk("Warning: CPU frequency is"
+ pr_debug("Warning: CPU frequency is"
" %u, cpufreq assumed %u kHz.\n",
freqs->old, policy->cur);
freqs->old = policy->cur;
@@ -353,7 +263,7 @@
case CPUFREQ_POSTCHANGE:
adjust_jiffies(CPUFREQ_POSTCHANGE, freqs);
- dprintk("FREQ: %lu - CPU: %lu", (unsigned long)freqs->new,
+ pr_debug("FREQ: %lu - CPU: %lu", (unsigned long)freqs->new,
(unsigned long)freqs->cpu);
trace_power_frequency(POWER_PSTATE, freqs->new, freqs->cpu);
trace_cpu_frequency(freqs->new, freqs->cpu);
@@ -753,7 +663,7 @@
static void cpufreq_sysfs_release(struct kobject *kobj)
{
struct cpufreq_policy *policy = to_policy(kobj);
- dprintk("last reference is dropped\n");
+ pr_debug("last reference is dropped\n");
complete(&policy->kobj_unregister);
}
@@ -788,7 +698,7 @@
gov = __find_governor(per_cpu(cpufreq_cpu_governor, cpu));
if (gov) {
policy->governor = gov;
- dprintk("Restoring governor %s for cpu %d\n",
+ pr_debug("Restoring governor %s for cpu %d\n",
policy->governor->name, cpu);
}
#endif
@@ -824,7 +734,7 @@
per_cpu(cpufreq_cpu_data, cpu) = managed_policy;
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
- dprintk("CPU already managed, adding link\n");
+ pr_debug("CPU already managed, adding link\n");
ret = sysfs_create_link(&sys_dev->kobj,
&managed_policy->kobj,
"cpufreq");
@@ -865,7 +775,7 @@
if (!cpu_online(j))
continue;
- dprintk("CPU %u already managed, adding link\n", j);
+ pr_debug("CPU %u already managed, adding link\n", j);
managed_policy = cpufreq_cpu_get(cpu);
cpu_sys_dev = get_cpu_sysdev(j);
ret = sysfs_create_link(&cpu_sys_dev->kobj, &policy->kobj,
@@ -941,7 +851,7 @@
policy->user_policy.governor = policy->governor;
if (ret) {
- dprintk("setting policy failed\n");
+ pr_debug("setting policy failed\n");
if (cpufreq_driver->exit)
cpufreq_driver->exit(policy);
}
@@ -977,8 +887,7 @@
if (cpu_is_offline(cpu))
return 0;
- cpufreq_debug_disable_ratelimit();
- dprintk("adding CPU %u\n", cpu);
+ pr_debug("adding CPU %u\n", cpu);
#ifdef CONFIG_SMP
/* check whether a different CPU already registered this
@@ -986,7 +895,6 @@
policy = cpufreq_cpu_get(cpu);
if (unlikely(policy)) {
cpufreq_cpu_put(policy);
- cpufreq_debug_enable_ratelimit();
return 0;
}
#endif
@@ -1037,7 +945,7 @@
*/
ret = cpufreq_driver->init(policy);
if (ret) {
- dprintk("initialization failed\n");
+ pr_debug("initialization failed\n");
goto err_unlock_policy;
}
policy->user_policy.min = policy->min;
@@ -1063,8 +971,7 @@
kobject_uevent(&policy->kobj, KOBJ_ADD);
module_put(cpufreq_driver->owner);
- dprintk("initialization complete\n");
- cpufreq_debug_enable_ratelimit();
+ pr_debug("initialization complete\n");
return 0;
@@ -1088,7 +995,6 @@
nomem_out:
module_put(cpufreq_driver->owner);
module_out:
- cpufreq_debug_enable_ratelimit();
return ret;
}
@@ -1112,15 +1018,13 @@
unsigned int j;
#endif
- cpufreq_debug_disable_ratelimit();
- dprintk("unregistering CPU %u\n", cpu);
+ pr_debug("unregistering CPU %u\n", cpu);
spin_lock_irqsave(&cpufreq_driver_lock, flags);
data = per_cpu(cpufreq_cpu_data, cpu);
if (!data) {
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
- cpufreq_debug_enable_ratelimit();
unlock_policy_rwsem_write(cpu);
return -EINVAL;
}
@@ -1132,12 +1036,11 @@
* only need to unlink, put and exit
*/
if (unlikely(cpu != data->cpu)) {
- dprintk("removing link\n");
+ pr_debug("removing link\n");
cpumask_clear_cpu(cpu, data->cpus);
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
kobj = &sys_dev->kobj;
cpufreq_cpu_put(data);
- cpufreq_debug_enable_ratelimit();
unlock_policy_rwsem_write(cpu);
sysfs_remove_link(kobj, "cpufreq");
return 0;
@@ -1170,7 +1073,7 @@
for_each_cpu(j, data->cpus) {
if (j == cpu)
continue;
- dprintk("removing link for cpu %u\n", j);
+ pr_debug("removing link for cpu %u\n", j);
#ifdef CONFIG_HOTPLUG_CPU
strncpy(per_cpu(cpufreq_cpu_governor, j),
data->governor->name, CPUFREQ_NAME_LEN);
@@ -1199,17 +1102,15 @@
* not referenced anymore by anybody before we proceed with
* unloading.
*/
- dprintk("waiting for dropping of refcount\n");
+ pr_debug("waiting for dropping of refcount\n");
wait_for_completion(cmp);
- dprintk("wait complete\n");
+ pr_debug("wait complete\n");
lock_policy_rwsem_write(cpu);
if (cpufreq_driver->exit)
cpufreq_driver->exit(data);
unlock_policy_rwsem_write(cpu);
- cpufreq_debug_enable_ratelimit();
-
#ifdef CONFIG_HOTPLUG_CPU
/* when the CPU which is the parent of the kobj is hotplugged
* offline, check for siblings, and create cpufreq sysfs interface
@@ -1255,7 +1156,7 @@
struct cpufreq_policy *policy =
container_of(work, struct cpufreq_policy, update);
unsigned int cpu = policy->cpu;
- dprintk("handle_update for cpu %u called\n", cpu);
+ pr_debug("handle_update for cpu %u called\n", cpu);
cpufreq_update_policy(cpu);
}
@@ -1273,7 +1174,7 @@
{
struct cpufreq_freqs freqs;
- dprintk("Warning: CPU frequency out of sync: cpufreq and timing "
+ pr_debug("Warning: CPU frequency out of sync: cpufreq and timing "
"core thinks of %u, is %u kHz.\n", old_freq, new_freq);
freqs.cpu = cpu;
@@ -1376,7 +1277,7 @@
int cpu = smp_processor_id();
struct cpufreq_policy *cpu_policy;
- dprintk("suspending cpu %u\n", cpu);
+ pr_debug("suspending cpu %u\n", cpu);
/* If there's no policy for the boot CPU, we have nothing to do. */
cpu_policy = cpufreq_cpu_get(cpu);
@@ -1414,7 +1315,7 @@
int cpu = smp_processor_id();
struct cpufreq_policy *cpu_policy;
- dprintk("resuming cpu %u\n", cpu);
+ pr_debug("resuming cpu %u\n", cpu);
/* If there's no policy for the boot CPU, we have nothing to do. */
cpu_policy = cpufreq_cpu_get(cpu);
@@ -1526,7 +1427,7 @@
{
int retval = -EINVAL;
- dprintk("target for CPU %u: %u kHz, relation %u\n", policy->cpu,
+ pr_debug("target for CPU %u: %u kHz, relation %u\n", policy->cpu,
target_freq, relation);
if (cpu_online(policy->cpu) && cpufreq_driver->target)
retval = cpufreq_driver->target(policy, target_freq, relation);
@@ -1612,7 +1513,7 @@
if (!try_module_get(policy->governor->owner))
return -EINVAL;
- dprintk("__cpufreq_governor for CPU %u, event %u\n",
+ pr_debug("__cpufreq_governor for CPU %u, event %u\n",
policy->cpu, event);
ret = policy->governor->governor(policy, event);
@@ -1713,8 +1614,7 @@
{
int ret = 0;
- cpufreq_debug_disable_ratelimit();
- dprintk("setting new policy for CPU %u: %u - %u kHz\n", policy->cpu,
+ pr_debug("setting new policy for CPU %u: %u - %u kHz\n", policy->cpu,
policy->min, policy->max);
memcpy(&policy->cpuinfo, &data->cpuinfo,
@@ -1751,19 +1651,19 @@
data->min = policy->min;
data->max = policy->max;
- dprintk("new min and max freqs are %u - %u kHz\n",
+ pr_debug("new min and max freqs are %u - %u kHz\n",
data->min, data->max);
if (cpufreq_driver->setpolicy) {
data->policy = policy->policy;
- dprintk("setting range\n");
+ pr_debug("setting range\n");
ret = cpufreq_driver->setpolicy(policy);
} else {
if (policy->governor != data->governor) {
/* save old, working values */
struct cpufreq_governor *old_gov = data->governor;
- dprintk("governor switch\n");
+ pr_debug("governor switch\n");
/* end old governor */
if (data->governor)
@@ -1773,7 +1673,7 @@
data->governor = policy->governor;
if (__cpufreq_governor(data, CPUFREQ_GOV_START)) {
/* new governor failed, so re-start old one */
- dprintk("starting governor %s failed\n",
+ pr_debug("starting governor %s failed\n",
data->governor->name);
if (old_gov) {
data->governor = old_gov;
@@ -1785,12 +1685,11 @@
}
/* might be a policy change, too, so fall through */
}
- dprintk("governor: change or update limits\n");
+ pr_debug("governor: change or update limits\n");
__cpufreq_governor(data, CPUFREQ_GOV_LIMITS);
}
error_out:
- cpufreq_debug_enable_ratelimit();
return ret;
}
@@ -1817,7 +1716,7 @@
goto fail;
}
- dprintk("updating policy for CPU %u\n", cpu);
+ pr_debug("updating policy for CPU %u\n", cpu);
memcpy(&policy, data, sizeof(struct cpufreq_policy));
policy.min = data->user_policy.min;
policy.max = data->user_policy.max;
@@ -1829,7 +1728,7 @@
if (cpufreq_driver->get) {
policy.cur = cpufreq_driver->get(cpu);
if (!data->cur) {
- dprintk("Driver did not initialize current freq");
+ pr_debug("Driver did not initialize current freq");
data->cur = policy.cur;
} else {
if (data->cur != policy.cur)
@@ -1905,7 +1804,7 @@
((!driver_data->setpolicy) && (!driver_data->target)))
return -EINVAL;
- dprintk("trying to register driver %s\n", driver_data->name);
+ pr_debug("trying to register driver %s\n", driver_data->name);
if (driver_data->setpolicy)
driver_data->flags |= CPUFREQ_CONST_LOOPS;
@@ -1936,15 +1835,14 @@
/* if all ->init() calls failed, unregister */
if (ret) {
- dprintk("no CPU initialized for driver %s\n",
+ pr_debug("no CPU initialized for driver %s\n",
driver_data->name);
goto err_sysdev_unreg;
}
}
register_hotcpu_notifier(&cpufreq_cpu_notifier);
- dprintk("driver %s up and running\n", driver_data->name);
- cpufreq_debug_enable_ratelimit();
+ pr_debug("driver %s up and running\n", driver_data->name);
return 0;
err_sysdev_unreg:
@@ -1971,14 +1869,10 @@
{
unsigned long flags;
- cpufreq_debug_disable_ratelimit();
-
- if (!cpufreq_driver || (driver != cpufreq_driver)) {
- cpufreq_debug_enable_ratelimit();
+ if (!cpufreq_driver || (driver != cpufreq_driver))
return -EINVAL;
- }
- dprintk("unregistering driver %s\n", driver->name);
+ pr_debug("unregistering driver %s\n", driver->name);
sysdev_driver_unregister(&cpu_sysdev_class, &cpufreq_sysdev_driver);
unregister_hotcpu_notifier(&cpufreq_cpu_notifier);