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[PATCH 2/3] tracing: Record task flag NEED_RESCHED_LAZY.

Sebastian Andrzej Siewior posted 3 patches 1 year, 4 months ago
There is a newer version of this series
[PATCH 2/3] tracing: Record task flag NEED_RESCHED_LAZY.
Posted by Sebastian Andrzej Siewior 1 year, 4 months ago 
The scheduler added NEED_RESCHED_LAZY scheduling. Record this state as
part of trace flags and expose it in the need_resched field.

Record and expose NEED_RESCHED_LAZY.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 include/linux/trace_events.h |  1 +
 kernel/trace/trace.c         |  2 ++
 kernel/trace/trace_output.c  | 14 +++++++++++++-
 3 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
index d5c0fcf20f024..4cae6f2581379 100644
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -185,6 +185,7 @@ unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status);
 enum trace_flag_type {
 	TRACE_FLAG_IRQS_OFF		= 0x01,
 	TRACE_FLAG_NEED_RESCHED		= 0x02,
+	TRACE_FLAG_NEED_RESCHED_LAZY	= 0x04,
 	TRACE_FLAG_HARDIRQ		= 0x08,
 	TRACE_FLAG_SOFTIRQ		= 0x10,
 	TRACE_FLAG_PREEMPT_RESCHED	= 0x20,
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 1c69ca1f10886..29d7703751aa9 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2544,6 +2544,8 @@ unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status)
 		trace_flags |= TRACE_FLAG_NEED_RESCHED;
 	if (test_preempt_need_resched())
 		trace_flags |= TRACE_FLAG_PREEMPT_RESCHED;
+	if (tif_test_bit(TIF_NEED_RESCHED_LAZY))
+		trace_flags |= TRACE_FLAG_NEED_RESCHED_LAZY;
 	return (trace_flags << 16) | (min_t(unsigned int, pc & 0xff, 0xf)) |
 		(min_t(unsigned int, migration_disable_value(), 0xf)) << 4;
 }
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 829daa0764dd9..23ca2155306b1 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -463,17 +463,29 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 		!IS_ENABLED(CONFIG_TRACE_IRQFLAGS_SUPPORT) ? 'X' :
 		'.';
 
-	switch (entry->flags & (TRACE_FLAG_NEED_RESCHED |
+	switch (entry->flags & (TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY |
 				TRACE_FLAG_PREEMPT_RESCHED)) {
+	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY | TRACE_FLAG_PREEMPT_RESCHED:
+		need_resched = 'B';
+		break;
 	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED:
 		need_resched = 'N';
 		break;
+	case TRACE_FLAG_NEED_RESCHED_LAZY | TRACE_FLAG_PREEMPT_RESCHED:
+		need_resched = 'L';
+		break;
+	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY:
+		need_resched = 'b';
+		break;
 	case TRACE_FLAG_NEED_RESCHED:
 		need_resched = 'n';
 		break;
 	case TRACE_FLAG_PREEMPT_RESCHED:
 		need_resched = 'p';
 		break;
+	case TRACE_FLAG_NEED_RESCHED_LAZY:
+		need_resched = 'l';
+		break;
 	default:
 		need_resched = '.';
 		break;
-- 
2.45.2
Re: [PATCH 2/3] tracing: Record task flag NEED_RESCHED_LAZY.
Posted by Shrikanth Hegde 1 year, 3 months ago 

On 10/9/24 16:20, Sebastian Andrzej Siewior wrote:
> The scheduler added NEED_RESCHED_LAZY scheduling. Record this state as
> part of trace flags and expose it in the need_resched field.
> 
> Record and expose NEED_RESCHED_LAZY.
> 
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
> ---
>   include/linux/trace_events.h |  1 +
>   kernel/trace/trace.c         |  2 ++
>   kernel/trace/trace_output.c  | 14 +++++++++++++-
>   3 files changed, 16 insertions(+), 1 deletion(-)
> 
> diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
> index d5c0fcf20f024..4cae6f2581379 100644
> --- a/include/linux/trace_events.h
> +++ b/include/linux/trace_events.h
> @@ -185,6 +185,7 @@ unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status);
>   enum trace_flag_type {
>   	TRACE_FLAG_IRQS_OFF		= 0x01,
>   	TRACE_FLAG_NEED_RESCHED		= 0x02,
> +	TRACE_FLAG_NEED_RESCHED_LAZY	= 0x04,
>   	TRACE_FLAG_HARDIRQ		= 0x08,
>   	TRACE_FLAG_SOFTIRQ		= 0x10,
>   	TRACE_FLAG_PREEMPT_RESCHED	= 0x20,
> diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
> index 1c69ca1f10886..29d7703751aa9 100644
> --- a/kernel/trace/trace.c
> +++ b/kernel/trace/trace.c
> @@ -2544,6 +2544,8 @@ unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status)
>   		trace_flags |= TRACE_FLAG_NEED_RESCHED;
>   	if (test_preempt_need_resched())
>   		trace_flags |= TRACE_FLAG_PREEMPT_RESCHED;
> +	if (tif_test_bit(TIF_NEED_RESCHED_LAZY))
> +		trace_flags |= TRACE_FLAG_NEED_RESCHED_LAZY;
>   	return (trace_flags << 16) | (min_t(unsigned int, pc & 0xff, 0xf)) |
>   		(min_t(unsigned int, migration_disable_value(), 0xf)) << 4;
>   }
> diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
> index 829daa0764dd9..23ca2155306b1 100644
> --- a/kernel/trace/trace_output.c
> +++ b/kernel/trace/trace_output.c
> @@ -463,17 +463,29 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
>   		!IS_ENABLED(CONFIG_TRACE_IRQFLAGS_SUPPORT) ? 'X' :
>   		'.';
>   
> -	switch (entry->flags & (TRACE_FLAG_NEED_RESCHED |
> +	switch (entry->flags & (TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY |
>   				TRACE_FLAG_PREEMPT_RESCHED)) {
> +	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY | TRACE_FLAG_PREEMPT_RESCHED:
> +		need_resched = 'B';
> +		break;
>   	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED:
>   		need_resched = 'N';
>   		break;
> +	case TRACE_FLAG_NEED_RESCHED_LAZY | TRACE_FLAG_PREEMPT_RESCHED:
> +		need_resched = 'L';
> +		break;
> +	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY:
> +		need_resched = 'b';
> +		break;
>   	case TRACE_FLAG_NEED_RESCHED:
>   		need_resched = 'n';
>   		break;
>   	case TRACE_FLAG_PREEMPT_RESCHED:
>   		need_resched = 'p';
>   		break;
> +	case TRACE_FLAG_NEED_RESCHED_LAZY:
> +		need_resched = 'l';
> +		break;
>   	default:
>   		need_resched = '.';
>   		break;


Could you please update in Documentation/trace/ftrace.rst as well?
Re: [PATCH 2/3] tracing: Record task flag NEED_RESCHED_LAZY.
Posted by Ankur Arora 1 year, 4 months ago 
Sebastian Andrzej Siewior <bigeasy@linutronix.de> writes:

> The scheduler added NEED_RESCHED_LAZY scheduling. Record this state as
> part of trace flags and expose it in the need_resched field.
>
> Record and expose NEED_RESCHED_LAZY.
>
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
> ---
>  include/linux/trace_events.h |  1 +
>  kernel/trace/trace.c         |  2 ++
>  kernel/trace/trace_output.c  | 14 +++++++++++++-
>  3 files changed, 16 insertions(+), 1 deletion(-)
>
> diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
> index d5c0fcf20f024..4cae6f2581379 100644
> --- a/include/linux/trace_events.h
> +++ b/include/linux/trace_events.h
> @@ -185,6 +185,7 @@ unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status);
>  enum trace_flag_type {
>  	TRACE_FLAG_IRQS_OFF		= 0x01,
>  	TRACE_FLAG_NEED_RESCHED		= 0x02,
> +	TRACE_FLAG_NEED_RESCHED_LAZY	= 0x04,
>  	TRACE_FLAG_HARDIRQ		= 0x08,
>  	TRACE_FLAG_SOFTIRQ		= 0x10,
>  	TRACE_FLAG_PREEMPT_RESCHED	= 0x20,
> diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
> index 1c69ca1f10886..29d7703751aa9 100644
> --- a/kernel/trace/trace.c
> +++ b/kernel/trace/trace.c
> @@ -2544,6 +2544,8 @@ unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status)
>  		trace_flags |= TRACE_FLAG_NEED_RESCHED;
>  	if (test_preempt_need_resched())
>  		trace_flags |= TRACE_FLAG_PREEMPT_RESCHED;
> +	if (tif_test_bit(TIF_NEED_RESCHED_LAZY))

TIF_NEED_RESCHED_LAZY falls back to TIF_NEED_RESCHED without
CONFIG_ARCH_HAS_PREEMPT_LAZY. So, you might need to add an explicit
check for that as well.

With that,
 Reviewed-by: Ankur Arora <ankur.a.arora@oracle.com>

Ankur

> +		trace_flags |= TRACE_FLAG_NEED_RESCHED_LAZY;
>  	return (trace_flags << 16) | (min_t(unsigned int, pc & 0xff, 0xf)) |
>  		(min_t(unsigned int, migration_disable_value(), 0xf)) << 4;
>  }
> diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
> index 829daa0764dd9..23ca2155306b1 100644
> --- a/kernel/trace/trace_output.c
> +++ b/kernel/trace/trace_output.c
> @@ -463,17 +463,29 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
>  		!IS_ENABLED(CONFIG_TRACE_IRQFLAGS_SUPPORT) ? 'X' :
>  		'.';
>
> -	switch (entry->flags & (TRACE_FLAG_NEED_RESCHED |
> +	switch (entry->flags & (TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY |
>  				TRACE_FLAG_PREEMPT_RESCHED)) {
> +	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY | TRACE_FLAG_PREEMPT_RESCHED:
> +		need_resched = 'B';
> +		break;
>  	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED:
>  		need_resched = 'N';
>  		break;
> +	case TRACE_FLAG_NEED_RESCHED_LAZY | TRACE_FLAG_PREEMPT_RESCHED:
> +		need_resched = 'L';
> +		break;
> +	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY:
> +		need_resched = 'b';
> +		break;
>  	case TRACE_FLAG_NEED_RESCHED:
>  		need_resched = 'n';
>  		break;
>  	case TRACE_FLAG_PREEMPT_RESCHED:
>  		need_resched = 'p';
>  		break;
> +	case TRACE_FLAG_NEED_RESCHED_LAZY:
> +		need_resched = 'l';
> +		break;
>  	default:
>  		need_resched = '.';
>  		break;


--
ankur
Re: [PATCH 2/3] tracing: Record task flag NEED_RESCHED_LAZY.
Posted by Steven Rostedt 1 year, 4 months ago 
On Wed, 09 Oct 2024 10:30:28 -0700
Ankur Arora <ankur.a.arora@oracle.com> wrote:

> > +++ b/kernel/trace/trace.c
> > @@ -2544,6 +2544,8 @@ unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status)
> >  		trace_flags |= TRACE_FLAG_NEED_RESCHED;
> >  	if (test_preempt_need_resched())
> >  		trace_flags |= TRACE_FLAG_PREEMPT_RESCHED;
> > +	if (tif_test_bit(TIF_NEED_RESCHED_LAZY))  
> 
> TIF_NEED_RESCHED_LAZY falls back to TIF_NEED_RESCHED without
> CONFIG_ARCH_HAS_PREEMPT_LAZY. So, you might need to add an explicit
> check for that as well.
> 
> With that,
>  Reviewed-by: Ankur Arora <ankur.a.arora@oracle.com>
> 
> Ankur
> 

So this should be:

	if (IS_ENABLED(CONFIG_ARCH_HAS_PREEMPT_LAZY) &&
	    tif_test_bit(TIF_NEED_RESCHED_LAZY))

?

-- Steve


> > +		trace_flags |= TRACE_FLAG_NEED_RESCHED_LAZY;
> >  	return (trace_flags << 16) | (min_t(unsigned int, pc & 0xff, 0xf)) |
> >  		(min_t(unsigned int, migration_disable_value(), 0xf)) << 4;
> >  }
> > diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
> > index 829daa0764dd9..23ca2155306b1 100644
> > --- a/kernel/trace/trace_output.c
> > +++ b/kernel/trace/trace_output.c
> > @@ -463,17 +463,29 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
> >  		!IS_ENABLED(CONFIG_TRACE_IRQFLAGS_SUPPORT) ? 'X' :
> >  		'.';
> >
> > -	switch (entry->flags & (TRACE_FLAG_NEED_RESCHED |
> > +	switch (entry->flags & (TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY |
> >  				TRACE_FLAG_PREEMPT_RESCHED)) {
> > +	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY | TRACE_FLAG_PREEMPT_RESCHED:
> > +		need_resched = 'B';
> > +		break;
> >  	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED:
> >  		need_resched = 'N';
> >  		break;
> > +	case TRACE_FLAG_NEED_RESCHED_LAZY | TRACE_FLAG_PREEMPT_RESCHED:
> > +		need_resched = 'L';
> > +		break;
> > +	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY:
> > +		need_resched = 'b';
> > +		break;
> >  	case TRACE_FLAG_NEED_RESCHED:
> >  		need_resched = 'n';
> >  		break;
> >  	case TRACE_FLAG_PREEMPT_RESCHED:
> >  		need_resched = 'p';
> >  		break;
> > +	case TRACE_FLAG_NEED_RESCHED_LAZY:
> > +		need_resched = 'l';
> > +		break;
> >  	default:
> >  		need_resched = '.';
> >  		break;
Re: [PATCH 2/3] tracing: Record task flag NEED_RESCHED_LAZY.
Posted by Ankur Arora 1 year, 4 months ago 
Steven Rostedt <rostedt@goodmis.org> writes:

> On Wed, 09 Oct 2024 10:30:28 -0700
> Ankur Arora <ankur.a.arora@oracle.com> wrote:
>
>> > +++ b/kernel/trace/trace.c
>> > @@ -2544,6 +2544,8 @@ unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status)
>> >  		trace_flags |= TRACE_FLAG_NEED_RESCHED;
>> >  	if (test_preempt_need_resched())
>> >  		trace_flags |= TRACE_FLAG_PREEMPT_RESCHED;
>> > +	if (tif_test_bit(TIF_NEED_RESCHED_LAZY))
>>
>> TIF_NEED_RESCHED_LAZY falls back to TIF_NEED_RESCHED without
>> CONFIG_ARCH_HAS_PREEMPT_LAZY. So, you might need to add an explicit
>> check for that as well.
>>
>> With that,
>>  Reviewed-by: Ankur Arora <ankur.a.arora@oracle.com>
>>
>> Ankur
>>
>
> So this should be:
>
> 	if (IS_ENABLED(CONFIG_ARCH_HAS_PREEMPT_LAZY) &&
> 	    tif_test_bit(TIF_NEED_RESCHED_LAZY))
>
> ?

Yeah, exactly that.

--
ankur
Re: [PATCH 2/3] tracing: Record task flag NEED_RESCHED_LAZY.
Posted by Sebastian Andrzej Siewior 1 year, 4 months ago 
On 2024-10-09 11:49:41 [-0700], Ankur Arora wrote:
> > So this should be:
> >
> > 	if (IS_ENABLED(CONFIG_ARCH_HAS_PREEMPT_LAZY) &&
> > 	    tif_test_bit(TIF_NEED_RESCHED_LAZY))
> >
> > ?
> 
> Yeah, exactly that.

Okay, this makes sense, this is what I ended up with:

diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
index d5c0fcf20f024..4cae6f2581379 100644
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -185,6 +185,7 @@ unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status);
 enum trace_flag_type {
 	TRACE_FLAG_IRQS_OFF		= 0x01,
 	TRACE_FLAG_NEED_RESCHED		= 0x02,
+	TRACE_FLAG_NEED_RESCHED_LAZY	= 0x04,
 	TRACE_FLAG_HARDIRQ		= 0x08,
 	TRACE_FLAG_SOFTIRQ		= 0x10,
 	TRACE_FLAG_PREEMPT_RESCHED	= 0x20,
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 1c69ca1f10886..fb839d00aad12 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2544,6 +2544,8 @@ unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status)
 		trace_flags |= TRACE_FLAG_NEED_RESCHED;
 	if (test_preempt_need_resched())
 		trace_flags |= TRACE_FLAG_PREEMPT_RESCHED;
+	if (IS_ENABLED(CONFIG_ARCH_HAS_PREEMPT_LAZY) && tif_test_bit(TIF_NEED_RESCHED_LAZY))
+		trace_flags |= TRACE_FLAG_NEED_RESCHED_LAZY;
 	return (trace_flags << 16) | (min_t(unsigned int, pc & 0xff, 0xf)) |
 		(min_t(unsigned int, migration_disable_value(), 0xf)) << 4;
 }
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 829daa0764dd9..23ca2155306b1 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -463,17 +463,29 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 		!IS_ENABLED(CONFIG_TRACE_IRQFLAGS_SUPPORT) ? 'X' :
 		'.';
 
-	switch (entry->flags & (TRACE_FLAG_NEED_RESCHED |
+	switch (entry->flags & (TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY |
 				TRACE_FLAG_PREEMPT_RESCHED)) {
+	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY | TRACE_FLAG_PREEMPT_RESCHED:
+		need_resched = 'B';
+		break;
 	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED:
 		need_resched = 'N';
 		break;
+	case TRACE_FLAG_NEED_RESCHED_LAZY | TRACE_FLAG_PREEMPT_RESCHED:
+		need_resched = 'L';
+		break;
+	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY:
+		need_resched = 'b';
+		break;
 	case TRACE_FLAG_NEED_RESCHED:
 		need_resched = 'n';
 		break;
 	case TRACE_FLAG_PREEMPT_RESCHED:
 		need_resched = 'p';
 		break;
+	case TRACE_FLAG_NEED_RESCHED_LAZY:
+		need_resched = 'l';
+		break;
 	default:
 		need_resched = '.';
 		break;
-- 
2.45.2


Sebastian
Re: [PATCH 2/3] tracing: Record task flag NEED_RESCHED_LAZY.
Posted by Steven Rostedt 1 year, 4 months ago 
On Thu, 10 Oct 2024 12:56:11 +0200
Sebastian Andrzej Siewior <bigeasy@linutronix.de> wrote:

> +++ b/kernel/trace/trace.c
> @@ -2544,6 +2544,8 @@ unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status)
>  		trace_flags |= TRACE_FLAG_NEED_RESCHED;
>  	if (test_preempt_need_resched())
>  		trace_flags |= TRACE_FLAG_PREEMPT_RESCHED;
> +	if (IS_ENABLED(CONFIG_ARCH_HAS_PREEMPT_LAZY) && tif_test_bit(TIF_NEED_RESCHED_LAZY))
> +		trace_flags |= TRACE_FLAG_NEED_RESCHED_LAZY;
>  	return (trace_flags << 16) | (min_t(unsigned int, pc & 0xff, 0xf)) |
>  		(min_t(unsigned int, migration_disable_value(), 0xf)) << 4;
>  }

This is the only update you made from your previous version right?

If so, my reviewed-by stands.

-- Steve
Re: [PATCH 2/3] tracing: Record task flag NEED_RESCHED_LAZY.
Posted by Sebastian Andrzej Siewior 1 year, 4 months ago 
On 2024-10-10 10:52:14 [-0400], Steven Rostedt wrote:
> On Thu, 10 Oct 2024 12:56:11 +0200
> Sebastian Andrzej Siewior <bigeasy@linutronix.de> wrote:
> 
> > +++ b/kernel/trace/trace.c
> > @@ -2544,6 +2544,8 @@ unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status)
> >  		trace_flags |= TRACE_FLAG_NEED_RESCHED;
> >  	if (test_preempt_need_resched())
> >  		trace_flags |= TRACE_FLAG_PREEMPT_RESCHED;
> > +	if (IS_ENABLED(CONFIG_ARCH_HAS_PREEMPT_LAZY) && tif_test_bit(TIF_NEED_RESCHED_LAZY))
> > +		trace_flags |= TRACE_FLAG_NEED_RESCHED_LAZY;
> >  	return (trace_flags << 16) | (min_t(unsigned int, pc & 0xff, 0xf)) |
> >  		(min_t(unsigned int, migration_disable_value(), 0xf)) << 4;
> >  }
> 
> This is the only update you made from your previous version right?

Yes.

> If so, my reviewed-by stands.

Let me add your's and Ankur's.

> -- Steve

Sebastian
Re: [PATCH 2/3] tracing: Record task flag NEED_RESCHED_LAZY.
Posted by Steven Rostedt 1 year, 4 months ago 
On Wed,  9 Oct 2024 12:50:56 +0200
Sebastian Andrzej Siewior <bigeasy@linutronix.de> wrote:

> The scheduler added NEED_RESCHED_LAZY scheduling. Record this state as
> part of trace flags and expose it in the need_resched field.
> 
> Record and expose NEED_RESCHED_LAZY.
> 
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>

-- Steve

> ---
>  include/linux/trace_events.h |  1 +
>  kernel/trace/trace.c         |  2 ++
>  kernel/trace/trace_output.c  | 14 +++++++++++++-
>  3 files changed, 16 insertions(+), 1 deletion(-)

Patchew 2.1-devel-b67e4c2

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