[patch V3 06/29] latency_top: Simplify stack trace handling

From: Thomas Gleixner
Date: Thu Apr 25 2019 - 06:00:04 EST


Replace the indirection through struct stack_trace with an invocation of
the storage array based interface.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
kernel/latencytop.c | 17 ++---------------
1 file changed, 2 insertions(+), 15 deletions(-)

--- a/kernel/latencytop.c
+++ b/kernel/latencytop.c
@@ -141,20 +141,6 @@ account_global_scheduler_latency(struct
memcpy(&latency_record[i], lat, sizeof(struct latency_record));
}

-/*
- * Iterator to store a backtrace into a latency record entry
- */
-static inline void store_stacktrace(struct task_struct *tsk,
- struct latency_record *lat)
-{
- struct stack_trace trace;
-
- memset(&trace, 0, sizeof(trace));
- trace.max_entries = LT_BACKTRACEDEPTH;
- trace.entries = &lat->backtrace[0];
- save_stack_trace_tsk(tsk, &trace);
-}
-
/**
* __account_scheduler_latency - record an occurred latency
* @tsk - the task struct of the task hitting the latency
@@ -191,7 +177,8 @@ void __sched
lat.count = 1;
lat.time = usecs;
lat.max = usecs;
- store_stacktrace(tsk, &lat);
+
+ stack_trace_save_tsk(tsk, lat.backtrace, LT_BACKTRACEDEPTH, 0);

raw_spin_lock_irqsave(&latency_lock, flags);