| From: Kaitao Cheng <pilgrimtao@gmail.com> |
| Date: Tue, 31 Dec 2019 05:35:30 -0800 |
| Subject: kernel/trace: Fix do not unregister tracepoints when register |
| sched_migrate_task fail |
| |
| commit 50f9ad607ea891a9308e67b81f774c71736d1098 upstream. |
| |
| In the function, if register_trace_sched_migrate_task() returns error, |
| sched_switch/sched_wakeup_new/sched_wakeup won't unregister. That is |
| why fail_deprobe_sched_switch was added. |
| |
| Link: http://lkml.kernel.org/r/20191231133530.2794-1-pilgrimtao@gmail.com |
| |
| Fixes: 478142c39c8c2 ("tracing: do not grab lock in wakeup latency function tracing") |
| Signed-off-by: Kaitao Cheng <pilgrimtao@gmail.com> |
| Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> |
| Signed-off-by: Ben Hutchings <ben@decadent.org.uk> |
| --- |
| kernel/trace/trace_sched_wakeup.c | 4 +++- |
| 1 file changed, 3 insertions(+), 1 deletion(-) |
| |
| --- a/kernel/trace/trace_sched_wakeup.c |
| +++ b/kernel/trace/trace_sched_wakeup.c |
| @@ -567,7 +567,7 @@ static void start_wakeup_tracer(struct t |
| if (ret) { |
| pr_info("wakeup trace: Couldn't activate tracepoint" |
| " probe to kernel_sched_migrate_task\n"); |
| - return; |
| + goto fail_deprobe_sched_switch; |
| } |
| |
| wakeup_reset(tr); |
| @@ -585,6 +585,8 @@ static void start_wakeup_tracer(struct t |
| printk(KERN_ERR "failed to start wakeup tracer\n"); |
| |
| return; |
| +fail_deprobe_sched_switch: |
| + unregister_trace_sched_switch(probe_wakeup_sched_switch, NULL); |
| fail_deprobe_wake_new: |
| unregister_trace_sched_wakeup_new(probe_wakeup, NULL); |
| fail_deprobe: |
