Sebastian Andrzej Siewior <[email protected]> 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 <[email protected]>
> ---
>  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 <[email protected]>

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

Reply via email to