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Merge branches 'tracing/blktrace', 'tracing/ftrace', 'tracing/urgent' and 'linus' into tracing/core

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This commit is contained in:
Ingo Molnar
2009-02-04 20:45:41 +01:00
parent 939b366977 79fb0768fb 229c4ef8ae
commit ce70a0b472
4 changed files with 70 additions and 18 deletions
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65
kernel/trace/trace.c
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@@ -53,6 +53,11 @@ unsigned long __read_mostly tracing_thresh;
*/
static bool __read_mostly tracing_selftest_running;
/*
* If a tracer is running, we do not want to run SELFTEST.
*/
static bool __read_mostly tracing_selftest_disabled;
/* For tracers that don't implement custom flags */
static struct tracer_opt dummy_tracer_opt[] = {
{ }
@@ -110,14 +115,19 @@ static cpumask_var_t __read_mostly tracing_buffer_mask;
*/
int ftrace_dump_on_oops;
static int tracing_set_tracer(char *buf);
static int tracing_set_tracer(const char *buf);
#define BOOTUP_TRACER_SIZE 100
static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata;
static char *default_bootup_tracer;
static int __init set_ftrace(char *str)
{
tracing_set_tracer(str);
strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE);
default_bootup_tracer = bootup_tracer_buf;
return 1;
}
__setup("ftrace", set_ftrace);
__setup("ftrace=", set_ftrace);
static int __init set_ftrace_dump_on_oops(char *str)
{
@@ -469,7 +479,7 @@ int register_tracer(struct tracer *type)
type->flags->opts = dummy_tracer_opt;
#ifdef CONFIG_FTRACE_STARTUP_TEST
if (type->selftest) {
if (type->selftest && !tracing_selftest_disabled) {
struct tracer *saved_tracer = current_trace;
struct trace_array *tr = &global_trace;
int i;
@@ -511,8 +521,25 @@ int register_tracer(struct tracer *type)
out:
tracing_selftest_running = false;
mutex_unlock(&trace_types_lock);
lock_kernel();
if (!ret && default_bootup_tracer) {
if (!strncmp(default_bootup_tracer, type->name,
BOOTUP_TRACER_SIZE)) {
printk(KERN_INFO "Starting tracer '%s'\n",
type->name);
/* Do we want this tracer to start on bootup? */
tracing_set_tracer(type->name);
default_bootup_tracer = NULL;
/* disable other selftests, since this will break it. */
tracing_selftest_disabled = 1;
#ifdef CONFIG_FTRACE_STARTUP_TEST
printk(KERN_INFO "Disabling FTRACE selftests due"
" to running tracer '%s'\n", type->name);
#endif
}
}
lock_kernel();
return ret;
}
@@ -2166,7 +2193,7 @@ tracing_set_trace_read(struct file *filp, char __user *ubuf,
return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}
static int tracing_set_tracer(char *buf)
static int tracing_set_tracer(const char *buf)
{
struct trace_array *tr = &global_trace;
struct tracer *t;
@@ -3061,12 +3088,9 @@ __init static int tracer_alloc_buffers(void)
trace_init_cmdlines();
register_tracer(&nop_trace);
current_trace = &nop_trace;
#ifdef CONFIG_BOOT_TRACER
register_tracer(&boot_tracer);
current_trace = &boot_tracer;
current_trace->init(&global_trace);
#else
current_trace = &nop_trace;
#endif
/* All seems OK, enable tracing */
tracing_disabled = 0;
@@ -3084,5 +3108,26 @@ out_free_buffer_mask:
out:
return ret;
}
__init static int clear_boot_tracer(void)
{
/*
* The default tracer at boot buffer is an init section.
* This function is called in lateinit. If we did not
* find the boot tracer, then clear it out, to prevent
* later registration from accessing the buffer that is
* about to be freed.
*/
if (!default_bootup_tracer)
return 0;
printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n",
default_bootup_tracer);
default_bootup_tracer = NULL;
return 0;
}
early_initcall(tracer_alloc_buffers);
fs_initcall(tracer_init_debugfs);
late_initcall(clear_boot_tracer);