diff options
| -rw-r--r-- | kernel/trace/trace.c | 36 | ||||
| -rw-r--r-- | kernel/trace/trace.h | 1 | ||||
| -rw-r--r-- | kernel/trace/trace_events.c | 3 |
3 files changed, 38 insertions, 2 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index a5411b7414b..b90a827a464 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1559,10 +1559,10 @@ static int alloc_percpu_trace_buffer(void) return -ENOMEM; } +static int buffers_allocated; + void trace_printk_init_buffers(void) { - static int buffers_allocated; - if (buffers_allocated) return; @@ -1575,6 +1575,34 @@ void trace_printk_init_buffers(void) tracing_update_buffers(); buffers_allocated = 1; + + /* + * trace_printk_init_buffers() can be called by modules. + * If that happens, then we need to start cmdline recording + * directly here. If the global_trace.buffer is already + * allocated here, then this was called by module code. + */ + if (global_trace.buffer) + tracing_start_cmdline_record(); +} + +void trace_printk_start_comm(void) +{ + /* Start tracing comms if trace printk is set */ + if (!buffers_allocated) + return; + tracing_start_cmdline_record(); +} + +static void trace_printk_start_stop_comm(int enabled) +{ + if (!buffers_allocated) + return; + + if (enabled) + tracing_start_cmdline_record(); + else + tracing_stop_cmdline_record(); } /** @@ -2797,6 +2825,9 @@ static void set_tracer_flags(unsigned int mask, int enabled) if (mask == TRACE_ITER_OVERWRITE) ring_buffer_change_overwrite(global_trace.buffer, enabled); + + if (mask == TRACE_ITER_PRINTK) + trace_printk_start_stop_comm(enabled); } static ssize_t @@ -5099,6 +5130,7 @@ __init static int tracer_alloc_buffers(void) /* Only allocate trace_printk buffers if a trace_printk exists */ if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) + /* Must be called before global_trace.buffer is allocated */ trace_printk_init_buffers(); /* To save memory, keep the ring buffer size to its minimum */ diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index c56a233c006..7824a55bd3f 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -841,6 +841,7 @@ extern const char *__start___trace_bprintk_fmt[]; extern const char *__stop___trace_bprintk_fmt[]; void trace_printk_init_buffers(void); +void trace_printk_start_comm(void); #undef FTRACE_ENTRY #define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter) \ diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index d608d09d08c..dec47e70e25 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -1489,6 +1489,9 @@ static __init int event_trace_enable(void) if (ret) pr_warn("Failed to enable trace event: %s\n", token); } + + trace_printk_start_comm(); + return 0; } |