On Tue, 1 Aug 2023 17:01:22 +0800
Ze Gao <zegao2021@xxxxxxxxx> wrote:
> Report priorities in 'short' and prev_state in 'int' to save
> some buffer space. And also reorder the fields so that we take
> struct alignment into consideration to make the record compact.
>
> Suggested-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
> Signed-off-by: Ze Gao <zegao@xxxxxxxxxxx>
I'd swap this patch with patch 3. That is, make the field changes first.
I'd like this to get in regardless of if the state_char is accepted. We may
want to get this in first to see if there's any regressions before we add a
state_char.
-- Steve
> ---
> include/trace/events/sched.h | 22 +++++++++++-----------
> 1 file changed, 11 insertions(+), 11 deletions(-)
>
> diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h
> index e507901bcab8..36863ffb00c6 100644
> --- a/include/trace/events/sched.h
> +++ b/include/trace/events/sched.h
> @@ -188,7 +188,7 @@ DEFINE_EVENT(sched_wakeup_template, sched_wakeup_new,
> TP_ARGS(p));
>
> #ifdef CREATE_TRACE_POINTS
> -static inline long __trace_sched_switch_state(bool preempt,
> +static inline int __trace_sched_switch_state(bool preempt,
> unsigned int prev_state,
> struct task_struct *p)
> {
> @@ -251,25 +251,25 @@ TRACE_EVENT(sched_switch,
> TP_ARGS(preempt, prev, next, prev_state),
>
> TP_STRUCT__entry(
> - __array( char, prev_comm, TASK_COMM_LEN )
> __field( pid_t, prev_pid )
> - __field( int, prev_prio )
> - __field( long, prev_state )
> - __field( char, prev_state_char )
> - __array( char, next_comm, TASK_COMM_LEN )
> __field( pid_t, next_pid )
> - __field( int, next_prio )
> + __field( short, prev_prio )
> + __field( short, next_prio )
> + __field( int, prev_state )
> + __array( char, prev_comm, TASK_COMM_LEN )
> + __array( char, next_comm, TASK_COMM_LEN )
> + __field( char, prev_state_char )
> ),
>
> TP_fast_assign(
> - memcpy(__entry->next_comm, next->comm, TASK_COMM_LEN);
> __entry->prev_pid = prev->pid;
> - __entry->prev_prio = prev->prio;
> + __entry->next_pid = next->pid;
> + __entry->prev_prio = (short) prev->prio;
> + __entry->next_prio = (short) next->prio;
> __entry->prev_state = __trace_sched_switch_state(preempt, prev_state, prev);
> __entry->prev_state_char = __trace_sched_switch_state_char(preempt, prev_state, prev);
> memcpy(__entry->prev_comm, prev->comm, TASK_COMM_LEN);
> - __entry->next_pid = next->pid;
> - __entry->next_prio = next->prio;
> + memcpy(__entry->next_comm, next->comm, TASK_COMM_LEN);
> /* XXX SCHED_DEADLINE */
> ),
>
|