diff options
| -rw-r--r-- | kernel/trace/trace_events.c | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 6591d83e1e7..f81d6eec4e4 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -8,10 +8,14 @@ * */ +#include <linux/workqueue.h> +#include <linux/spinlock.h> +#include <linux/kthread.h> #include <linux/debugfs.h> #include <linux/uaccess.h> #include <linux/module.h> #include <linux/ctype.h> +#include <linux/delay.h> #include "trace_output.h" @@ -920,3 +924,177 @@ static __init int event_trace_init(void) return 0; } fs_initcall(event_trace_init); + +#ifdef CONFIG_FTRACE_STARTUP_TEST + +static DEFINE_SPINLOCK(test_spinlock); +static DEFINE_SPINLOCK(test_spinlock_irq); +static DEFINE_MUTEX(test_mutex); + +static __init void test_work(struct work_struct *dummy) +{ + spin_lock(&test_spinlock); + spin_lock_irq(&test_spinlock_irq); + udelay(1); + spin_unlock_irq(&test_spinlock_irq); + spin_unlock(&test_spinlock); + + mutex_lock(&test_mutex); + msleep(1); + mutex_unlock(&test_mutex); +} + +static __init int event_test_thread(void *unused) +{ + void *test_malloc; + + test_malloc = kmalloc(1234, GFP_KERNEL); + if (!test_malloc) + pr_info("failed to kmalloc\n"); + + schedule_on_each_cpu(test_work); + + kfree(test_malloc); + + set_current_state(TASK_INTERRUPTIBLE); + while (!kthread_should_stop()) + schedule(); + + return 0; +} + +/* + * Do various things that may trigger events. + */ +static __init void event_test_stuff(void) +{ + struct task_struct *test_thread; + + test_thread = kthread_run(event_test_thread, NULL, "test-events"); + msleep(1); + kthread_stop(test_thread); +} + +/* + * For every trace event defined, we will test each trace point separately, + * and then by groups, and finally all trace points. + */ +static __init int event_trace_self_tests(void) +{ + struct ftrace_event_call *call; + struct event_subsystem *system; + char *sysname; + int ret; + + pr_info("Running tests on trace events:\n"); + + list_for_each_entry(call, &ftrace_events, list) { + + /* Only test those that have a regfunc */ + if (!call->regfunc) + continue; + + pr_info("Testing event %s: ", call->name); + + /* + * If an event is already enabled, someone is using + * it and the self test should not be on. + */ + if (call->enabled) { + pr_warning("Enabled event during self test!\n"); + WARN_ON_ONCE(1); + continue; + } + + call->enabled = 1; + call->regfunc(); + + event_test_stuff(); + + call->unregfunc(); + call->enabled = 0; + + pr_cont("OK\n"); + } + + /* Now test at the sub system level */ + + pr_info("Running tests on trace event systems:\n"); + + list_for_each_entry(system, &event_subsystems, list) { + + /* the ftrace system is special, skip it */ + if (strcmp(system->name, "ftrace") == 0) + continue; + + pr_info("Testing event system %s: ", system->name); + + /* ftrace_set_clr_event can modify the name passed in. */ + sysname = kstrdup(system->name, GFP_KERNEL); + if (WARN_ON(!sysname)) { + pr_warning("Can't allocate memory, giving up!\n"); + return 0; + } + ret = ftrace_set_clr_event(sysname, 1); + kfree(sysname); + if (WARN_ON_ONCE(ret)) { + pr_warning("error enabling system %s\n", + system->name); + continue; + } + + event_test_stuff(); + + sysname = kstrdup(system->name, GFP_KERNEL); + if (WARN_ON(!sysname)) { + pr_warning("Can't allocate memory, giving up!\n"); + return 0; + } + ret = ftrace_set_clr_event(sysname, 0); + kfree(sysname); + + if (WARN_ON_ONCE(ret)) + pr_warning("error disabling system %s\n", + system->name); + + pr_cont("OK\n"); + } + + /* Test with all events enabled */ + + pr_info("Running tests on all trace events:\n"); + pr_info("Testing all events: "); + + sysname = kmalloc(4, GFP_KERNEL); + if (WARN_ON(!sysname)) { + pr_warning("Can't allocate memory, giving up!\n"); + return 0; + } + memcpy(sysname, "*:*", 4); + ret = ftrace_set_clr_event(sysname, 1); + if (WARN_ON_ONCE(ret)) { + kfree(sysname); + pr_warning("error enabling all events\n"); + return 0; + } + + event_test_stuff(); + + /* reset sysname */ + memcpy(sysname, "*:*", 4); + ret = ftrace_set_clr_event(sysname, 0); + kfree(sysname); + + if (WARN_ON_ONCE(ret)) { + pr_warning("error disabling all events\n"); + return 0; + } + + pr_cont("OK\n"); + + return 0; +} + +late_initcall(event_trace_self_tests); + +#endif |