[PATCHv2 1/2] trace/hwlat: Do not wipe the contents of per-cpu thread data

From: Tero Kristo
Date: Fri Mar 10 2023 - 05:05:15 EST


Do not wipe the contents of the per-cpu kthread data when starting the
tracer, as this will completely forget about already running instances
and can later start new additional per-cpu threads.

Signed-off-by: Tero Kristo <tero.kristo@xxxxxxxxxxxxxxx>
---
v2:
* split into separate patch

kernel/trace/trace_hwlat.c | 3 ---
1 file changed, 3 deletions(-)

diff --git a/kernel/trace/trace_hwlat.c b/kernel/trace/trace_hwlat.c
index d440ddd5fd8b..edc26dc22c3f 100644
--- a/kernel/trace/trace_hwlat.c
+++ b/kernel/trace/trace_hwlat.c
@@ -584,9 +584,6 @@ static int start_per_cpu_kthreads(struct trace_array *tr)
*/
cpumask_and(current_mask, cpu_online_mask, tr->tracing_cpumask);

- for_each_online_cpu(cpu)
- per_cpu(hwlat_per_cpu_data, cpu).kthread = NULL;
-
for_each_cpu(cpu, current_mask) {
retval = start_cpu_kthread(cpu);
if (retval)
--
2.25.1