[RFC PATCH v6 3/5] sched, tracing: reorganize fields of switch event struct
From: Ze Gao <hidden>
Date: 2023-08-03 08:36:53
Also in:
linux-perf-users, lkml
Subsystem:
the rest, tracing · Maintainers:
Linus Torvalds, Steven Rostedt, Masami Hiramatsu
Report prioritiy and prev_state in 'short' 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@goodmis.org> Signed-off-by: Ze Gao <redacted> --- include/trace/events/sched.h | 26 +++++++++++++------------- 1 file changed, 13 insertions(+), 13 deletions(-)
diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h
index fbb99a61f714..43492daefa6f 100644
--- a/include/trace/events/sched.h
+++ b/include/trace/events/sched.h@@ -187,14 +187,14 @@ 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 short __trace_sched_switch_state(bool preempt, unsigned int prev_state, struct task_struct *p) { unsigned int state; #ifdef CONFIG_SCHED_DEBUG - BUG_ON(p != current); + WARN_ON_ONCE(p != current); #endif /* CONFIG_SCHED_DEBUG */ /*
@@ -229,23 +229,23 @@ 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 ) - __array( char, next_comm, TASK_COMM_LEN ) __field( pid_t, next_pid ) - __field( int, next_prio ) + __field( short, prev_prio ) + __field( short, next_prio ) + __array( char, prev_comm, TASK_COMM_LEN ) + __array( char, next_comm, TASK_COMM_LEN ) + __field( short, prev_state ) ), TP_fast_assign( - memcpy(__entry->next_comm, next->comm, TASK_COMM_LEN); - __entry->prev_pid = prev->pid; - __entry->prev_prio = prev->prio; - __entry->prev_state = __trace_sched_switch_state(preempt, prev_state, prev); + __entry->prev_pid = prev->pid; + __entry->next_pid = next->pid; + __entry->prev_prio = (short) prev->prio; + __entry->next_prio = (short) next->prio; 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); + __entry->prev_state = __trace_sched_switch_state(preempt, prev_state, prev); /* XXX SCHED_DEADLINE */ ),
--
2.41.0