2022-07-23 07:02:45

by Anand Je Saipureddy

[permalink] [raw]
Subject: [PATCH] ftrace: Fix improper usage of __trace_stack() function.

In kernel/trace/trace_events_trigger.c --> stacktrace_trigger() -->
__trace_stack() is not defined as per the function definition.

With commit edbaaa13a660
("tracing: Merge irqflags + preemt counter, add RT bits")
the irqflags(flags) and preemption counter(preempt_count()) are
now should be evaluated early by tracing_gen_ctx().

This patch replaces the irqflags and preemption counter
with tracing_gen_ctx().

Fixes: 5e8446e3820c ("tracing: Dump stacktrace trigger to the corresponding instance")
Signed-off-by: Anand Je Saipureddy <[email protected]>
Reviewed-by: Corey Minyard <[email protected]>
---
kernel/trace/trace_events_trigger.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
index 75fef9fcfd0f..3c6229f16e81 100644
--- a/kernel/trace/trace_events_trigger.c
+++ b/kernel/trace/trace_events_trigger.c
@@ -1220,12 +1220,10 @@ stacktrace_trigger(struct event_trigger_data *data, void *rec,
struct ring_buffer_event *event)
{
struct trace_event_file *file = data->private_data;
- unsigned long flags;

- if (file) {
- local_save_flags(flags);
- __trace_stack(file->tr, STACK_SKIP, preempt_count());
- } else
+ if (file)
+ __trace_stack(file->tr, tracing_gen_ctx(), STACK_SKIP);
+ else
trace_dump_stack(STACK_SKIP);
}

--
2.25.1
This patch is applicable only for linux-stable-rt kernel of branch
v5.10-rt


Subject: Re: [PATCH] ftrace: Fix improper usage of __trace_stack() function.

On 2022-07-23 12:19:43 [+0530], Anand Je Saipureddy wrote:
> In kernel/trace/trace_events_trigger.c --> stacktrace_trigger() -->
> __trace_stack() is not defined as per the function definition.
>
> With commit edbaaa13a660
> ("tracing: Merge irqflags + preemt counter, add RT bits")
> the irqflags(flags) and preemption counter(preempt_count()) are
> now should be evaluated early by tracing_gen_ctx().
>
> This patch replaces the irqflags and preemption counter
> with tracing_gen_ctx().
>
> Fixes: 5e8446e3820c ("tracing: Dump stacktrace trigger to the corresponding instance")
> Signed-off-by: Anand Je Saipureddy <[email protected]>
> Reviewed-by: Corey Minyard <[email protected]>

Please use [PATCH RT v5.10] in the future.
Luis, could you please pick it up?

> ---
> kernel/trace/trace_events_trigger.c | 8 +++-----
> 1 file changed, 3 insertions(+), 5 deletions(-)
>
> diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
> index 75fef9fcfd0f..3c6229f16e81 100644
> --- a/kernel/trace/trace_events_trigger.c
> +++ b/kernel/trace/trace_events_trigger.c
> @@ -1220,12 +1220,10 @@ stacktrace_trigger(struct event_trigger_data *data, void *rec,
> struct ring_buffer_event *event)
> {
> struct trace_event_file *file = data->private_data;
> - unsigned long flags;
>
> - if (file) {
> - local_save_flags(flags);
> - __trace_stack(file->tr, STACK_SKIP, preempt_count());
> - } else
> + if (file)
> + __trace_stack(file->tr, tracing_gen_ctx(), STACK_SKIP);
> + else
> trace_dump_stack(STACK_SKIP);
> }
>

Sebastian

Subject: Re: [PATCH] ftrace: Fix improper usage of __trace_stack() function.

On Wed, Aug 03, 2022 at 09:50:17AM +0200, Sebastian Andrzej Siewior wrote:
> On 2022-07-23 12:19:43 [+0530], Anand Je Saipureddy wrote:
> > In kernel/trace/trace_events_trigger.c --> stacktrace_trigger() -->
> > __trace_stack() is not defined as per the function definition.
> >
> > With commit edbaaa13a660
> > ("tracing: Merge irqflags + preemt counter, add RT bits")
> > the irqflags(flags) and preemption counter(preempt_count()) are
> > now should be evaluated early by tracing_gen_ctx().
> >
> > This patch replaces the irqflags and preemption counter
> > with tracing_gen_ctx().
> >
> > Fixes: 5e8446e3820c ("tracing: Dump stacktrace trigger to the corresponding instance")
> > Signed-off-by: Anand Je Saipureddy <[email protected]>
> > Reviewed-by: Corey Minyard <[email protected]>
>
> Please use [PATCH RT v5.10] in the future.
> Luis, could you please pick it up?

Added to the list.

And thank you for spotting this change, I missed that in my earlier sweep.

Luis

> > ---
> > kernel/trace/trace_events_trigger.c | 8 +++-----
> > 1 file changed, 3 insertions(+), 5 deletions(-)
> >
> > diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
> > index 75fef9fcfd0f..3c6229f16e81 100644
> > --- a/kernel/trace/trace_events_trigger.c
> > +++ b/kernel/trace/trace_events_trigger.c
> > @@ -1220,12 +1220,10 @@ stacktrace_trigger(struct event_trigger_data *data, void *rec,
> > struct ring_buffer_event *event)
> > {
> > struct trace_event_file *file = data->private_data;
> > - unsigned long flags;
> >
> > - if (file) {
> > - local_save_flags(flags);
> > - __trace_stack(file->tr, STACK_SKIP, preempt_count());
> > - } else
> > + if (file)
> > + __trace_stack(file->tr, tracing_gen_ctx(), STACK_SKIP);
> > + else
> > trace_dump_stack(STACK_SKIP);
> > }
> >
>
> Sebastian
>
---end quoted text---