kpriv/linux-hardened
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

tracing/ftrace: change the type of the init() callback

Browse source 
Impact: extend the ->init() method with the ability to fail

This bring a way to know if the initialization of a tracer successed.
A tracer must return 0 on success and a traditional error (ie:
-ENOMEM) if it fails.

If a tracer fails to init, it is free to print a detailed warn. The
tracing api will not and switch to a new tracer will just return the
error from the init callback.

Note: this will be used for the return tracer.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Frederic Weisbecker 2008-11-16 05:57:26 +01:00 committed by Ingo Molnar
parent e6e7a65aab
commit 1c80025a49
13 changed files with 88 additions and 24 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

7
kernel/trace/trace.c
View file

@ -2638,8 +2638,11 @@ static int tracing_set_tracer(char *buf)
current_trace->reset(tr);
current_trace = t;
if (t->init)
t->init(tr);
if (t->init) {
ret = t->init(tr);
if (ret)
goto out;
}
trace_branch_enable(tr);
out:

3
kernel/trace/trace.h
View file

@ -264,7 +264,8 @@ enum print_line_t {
*/
struct tracer {
const char *name;
void (*init)(struct trace_array *tr);
/* Your tracer should raise a warning if init fails */
int (*init)(struct trace_array *tr);
void (*reset)(struct trace_array *tr);
void (*start)(struct trace_array *tr);
void (*stop)(struct trace_array *tr);

3
kernel/trace/trace_boot.c
View file

@ -47,7 +47,7 @@ static void reset_boot_trace(struct trace_array *tr)
tracing_reset(tr, cpu);
}
static void boot_trace_init(struct trace_array *tr)
static int boot_trace_init(struct trace_array *tr)
{
int cpu;
boot_trace = tr;
@ -56,6 +56,7 @@ static void boot_trace_init(struct trace_array *tr)
tracing_reset(tr, cpu);
tracing_sched_switch_assign_trace(tr);
return 0;
}
static enum print_line_t

3
kernel/trace/trace_branch.c
View file

@ -125,7 +125,7 @@ static void stop_branch_trace(struct trace_array *tr)
disable_branch_tracing();
}
static void branch_trace_init(struct trace_array *tr)
static int branch_trace_init(struct trace_array *tr)
{
int cpu;
@ -133,6 +133,7 @@ static void branch_trace_init(struct trace_array *tr)
tracing_reset(tr, cpu);
start_branch_trace(tr);
return 0;
}
static void branch_trace_reset(struct trace_array *tr)

3
kernel/trace/trace_functions.c
View file

@ -42,9 +42,10 @@ static void stop_function_trace(struct trace_array *tr)
tracing_stop_cmdline_record();
}
static void function_trace_init(struct trace_array *tr)
static int function_trace_init(struct trace_array *tr)
{
start_function_trace(tr);
return 0;
}
static void function_trace_reset(struct trace_array *tr)

3
kernel/trace/trace_functions_return.c
View file

@ -24,13 +24,14 @@ static void stop_return_trace(struct trace_array *tr)
unregister_ftrace_return();
}
static void return_trace_init(struct trace_array *tr)
static int return_trace_init(struct trace_array *tr)
{
int cpu;
for_each_online_cpu(cpu)
tracing_reset(tr, cpu);
start_return_trace(tr);
return 0;
}
static void return_trace_reset(struct trace_array *tr)

9
kernel/trace/trace_irqsoff.c
View file

@ -416,11 +416,12 @@ static void irqsoff_tracer_close(struct trace_iterator *iter)
}
#ifdef CONFIG_IRQSOFF_TRACER
static void irqsoff_tracer_init(struct trace_array *tr)
static int irqsoff_tracer_init(struct trace_array *tr)
{
trace_type = TRACER_IRQS_OFF;
__irqsoff_tracer_init(tr);
return 0;
}
static struct tracer irqsoff_tracer __read_mostly =
{
@ -442,11 +443,12 @@ static struct tracer irqsoff_tracer __read_mostly =
#endif
#ifdef CONFIG_PREEMPT_TRACER
static void preemptoff_tracer_init(struct trace_array *tr)
static int preemptoff_tracer_init(struct trace_array *tr)
{
trace_type = TRACER_PREEMPT_OFF;
__irqsoff_tracer_init(tr);
return 0;
}
static struct tracer preemptoff_tracer __read_mostly =
@ -471,11 +473,12 @@ static struct tracer preemptoff_tracer __read_mostly =
#if defined(CONFIG_IRQSOFF_TRACER) && \
defined(CONFIG_PREEMPT_TRACER)
static void preemptirqsoff_tracer_init(struct trace_array *tr)
static int preemptirqsoff_tracer_init(struct trace_array *tr)
{
trace_type = TRACER_IRQS_OFF | TRACER_PREEMPT_OFF;
__irqsoff_tracer_init(tr);
return 0;
}
static struct tracer preemptirqsoff_tracer __read_mostly =

3
kernel/trace/trace_mmiotrace.c
View file

@ -30,13 +30,14 @@ static void mmio_reset_data(struct trace_array *tr)
tracing_reset(tr, cpu);
}
static void mmio_trace_init(struct trace_array *tr)
static int mmio_trace_init(struct trace_array *tr)
{
pr_debug("in %s\n", __func__);
mmio_trace_array = tr;
mmio_reset_data(tr);
enable_mmiotrace();
return 0;
}
static void mmio_trace_reset(struct trace_array *tr)

3
kernel/trace/trace_nop.c
View file

@ -24,7 +24,7 @@ static void stop_nop_trace(struct trace_array *tr)
/* Nothing to do! */
}
static void nop_trace_init(struct trace_array *tr)
static int nop_trace_init(struct trace_array *tr)
{
int cpu;
ctx_trace = tr;
@ -33,6 +33,7 @@ static void nop_trace_init(struct trace_array *tr)
tracing_reset(tr, cpu);
start_nop_trace(tr);
return 0;
}
static void nop_trace_reset(struct trace_array *tr)

3
kernel/trace/trace_sched_switch.c
View file

@ -206,10 +206,11 @@ static void stop_sched_trace(struct trace_array *tr)
tracing_stop_sched_switch_record();
}
static void sched_switch_trace_init(struct trace_array *tr)
static int sched_switch_trace_init(struct trace_array *tr)
{
ctx_trace = tr;
start_sched_trace(tr);
return 0;
}
static void sched_switch_trace_reset(struct trace_array *tr)

3
kernel/trace/trace_sched_wakeup.c
View file

@ -331,10 +331,11 @@ static void stop_wakeup_tracer(struct trace_array *tr)
unregister_trace_sched_wakeup(probe_wakeup);
}
static void wakeup_tracer_init(struct trace_array *tr)
static int wakeup_tracer_init(struct trace_array *tr)
{
wakeup_trace = tr;
start_wakeup_tracer(tr);
return 0;
}
static void wakeup_tracer_reset(struct trace_array *tr)

66
kernel/trace/trace_selftest.c
View file

@ -71,6 +71,11 @@ static int trace_test_buffer(struct trace_array *tr, unsigned long *count)
return ret;
}
static inline void warn_failed_init_tracer(struct tracer *trace, int init_ret)
{
printk(KERN_WARNING "Failed to init %s tracer, init returned %d\n",
trace->name, init_ret);
}
#ifdef CONFIG_FUNCTION_TRACER
#ifdef CONFIG_DYNAMIC_FTRACE
@ -111,7 +116,11 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
ftrace_set_filter(func_name, strlen(func_name), 1);
/* enable tracing */
trace->init(tr);
ret = trace->init(tr);
if (ret) {
warn_failed_init_tracer(trace, ret);
goto out;
}
/* Sleep for a 1/10 of a second */
msleep(100);
@ -181,7 +190,12 @@ trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr)
ftrace_enabled = 1;
tracer_enabled = 1;
trace->init(tr);
ret = trace->init(tr);
if (ret) {
warn_failed_init_tracer(trace, ret);
goto out;
}
/* Sleep for a 1/10 of a second */
msleep(100);
/* stop the tracing. */
@ -223,7 +237,12 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr)
int ret;
/* start the tracing */
trace->init(tr);
ret = trace->init(tr);
if (ret) {
warn_failed_init_tracer(trace, ret);
return ret;
}
/* reset the max latency */
tracing_max_latency = 0;
/* disable interrupts for a bit */
@ -272,7 +291,12 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr)
}
/* start the tracing */
trace->init(tr);
ret = trace->init(tr);
if (ret) {
warn_failed_init_tracer(trace, ret);
return ret;
}
/* reset the max latency */
tracing_max_latency = 0;
/* disable preemption for a bit */
@ -321,7 +345,11 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *
}
/* start the tracing */
trace->init(tr);
ret = trace->init(tr);
if (ret) {
warn_failed_init_tracer(trace, ret);
goto out;
}
/* reset the max latency */
tracing_max_latency = 0;
@ -449,7 +477,12 @@ trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr)
wait_for_completion(&isrt);
/* start the tracing */
trace->init(tr);
ret = trace->init(tr);
if (ret) {
warn_failed_init_tracer(trace, ret);
return ret;
}
/* reset the max latency */
tracing_max_latency = 0;
@ -505,7 +538,12 @@ trace_selftest_startup_sched_switch(struct tracer *trace, struct trace_array *tr
int ret;
/* start the tracing */
trace->init(tr);
ret = trace->init(tr);
if (ret) {
warn_failed_init_tracer(trace, ret);
return ret;
}
/* Sleep for a 1/10 of a second */
msleep(100);
/* stop the tracing. */
@ -532,7 +570,12 @@ trace_selftest_startup_sysprof(struct tracer *trace, struct trace_array *tr)
int ret;
/* start the tracing */
trace->init(tr);
ret = trace->init(tr);
if (ret) {
warn_failed_init_tracer(trace, ret);
return 0;
}
/* Sleep for a 1/10 of a second */
msleep(100);
/* stop the tracing. */
@ -554,7 +597,12 @@ trace_selftest_startup_branch(struct tracer *trace, struct trace_array *tr)
int ret;
/* start the tracing */
trace->init(tr);
ret = trace->init(tr);
if (ret) {
warn_failed_init_tracer(trace, ret);
return ret;
}
/* Sleep for a 1/10 of a second */
msleep(100);
/* stop the tracing. */

3
kernel/trace/trace_sysprof.c
View file

@ -261,11 +261,12 @@ static void stop_stack_trace(struct trace_array *tr)
mutex_unlock(&sample_timer_lock);
}
static void stack_trace_init(struct trace_array *tr)
static int stack_trace_init(struct trace_array *tr)
{
sysprof_trace = tr;
start_stack_trace(tr);
return 0;
}
static void stack_trace_reset(struct trace_array *tr)