diff options
Diffstat (limited to 'kernel/trace/trace_benchmark.c')
| -rw-r--r-- | kernel/trace/trace_benchmark.c | 26 |
1 files changed, 24 insertions, 2 deletions
diff --git a/kernel/trace/trace_benchmark.c b/kernel/trace/trace_benchmark.c index 0f109c4130d3..e3b488825ae3 100644 --- a/kernel/trace/trace_benchmark.c +++ b/kernel/trace/trace_benchmark.c @@ -21,6 +21,8 @@ static u64 bm_stddev; static unsigned int bm_avg; static unsigned int bm_std; +static bool ok_to_run; + /* * This gets called in a loop recording the time it took to write * the tracepoint. What it writes is the time statistics of the last @@ -164,11 +166,21 @@ static int benchmark_event_kthread(void *arg) * When the benchmark tracepoint is enabled, it calls this * function and the thread that calls the tracepoint is created. */ -void trace_benchmark_reg(void) +int trace_benchmark_reg(void) { + if (!ok_to_run) { + pr_warning("trace benchmark cannot be started via kernel command line\n"); + return -EBUSY; + } + bm_event_thread = kthread_run(benchmark_event_kthread, NULL, "event_benchmark"); - WARN_ON(!bm_event_thread); + if (!bm_event_thread) { + pr_warning("trace benchmark failed to create kernel thread\n"); + return -ENOMEM; + } + + return 0; } /* @@ -182,6 +194,7 @@ void trace_benchmark_unreg(void) return; kthread_stop(bm_event_thread); + bm_event_thread = NULL; strcpy(bm_str, "START"); bm_total = 0; @@ -196,3 +209,12 @@ void trace_benchmark_unreg(void) bm_avg = 0; bm_stddev = 0; } + +static __init int ok_to_run_trace_benchmark(void) +{ + ok_to_run = true; + + return 0; +} + +early_initcall(ok_to_run_trace_benchmark); |