diff options
Diffstat (limited to 'kernel/trace/trace.c')
-rw-r--r-- | kernel/trace/trace.c | 40 |
1 files changed, 25 insertions, 15 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 24c1f2382557..922657f30723 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1091,13 +1091,13 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) } #endif /* CONFIG_TRACER_MAX_TRACE */ -static void default_wait_pipe(struct trace_iterator *iter) +static int default_wait_pipe(struct trace_iterator *iter) { /* Iterators are static, they should be filled or empty */ if (trace_buffer_iter(iter, iter->cpu_file)) - return; + return 0; - ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file); + return ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file); } #ifdef CONFIG_FTRACE_STARTUP_TEST @@ -1355,7 +1355,6 @@ void tracing_start(void) arch_spin_unlock(&ftrace_max_lock); - ftrace_start(); out: raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); } @@ -1402,7 +1401,6 @@ void tracing_stop(void) struct ring_buffer *buffer; unsigned long flags; - ftrace_stop(); raw_spin_lock_irqsave(&global_trace.start_lock, flags); if (global_trace.stop_count++) goto out; @@ -1449,12 +1447,12 @@ static void tracing_stop_tr(struct trace_array *tr) void trace_stop_cmdline_recording(void); -static void trace_save_cmdline(struct task_struct *tsk) +static int trace_save_cmdline(struct task_struct *tsk) { unsigned pid, idx; if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) - return; + return 0; /* * It's not the end of the world if we don't get @@ -1463,7 +1461,7 @@ static void trace_save_cmdline(struct task_struct *tsk) * so if we miss here, then better luck next time. */ if (!arch_spin_trylock(&trace_cmdline_lock)) - return; + return 0; idx = map_pid_to_cmdline[tsk->pid]; if (idx == NO_CMDLINE_MAP) { @@ -1488,6 +1486,8 @@ static void trace_save_cmdline(struct task_struct *tsk) memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); arch_spin_unlock(&trace_cmdline_lock); + + return 1; } void trace_find_cmdline(int pid, char comm[]) @@ -1529,9 +1529,8 @@ void tracing_record_cmdline(struct task_struct *tsk) if (!__this_cpu_read(trace_cmdline_save)) return; - __this_cpu_write(trace_cmdline_save, false); - - trace_save_cmdline(tsk); + if (trace_save_cmdline(tsk)) + __this_cpu_write(trace_cmdline_save, false); } void @@ -4161,17 +4160,19 @@ tracing_poll_pipe(struct file *filp, poll_table *poll_table) * * Anyway, this is really very primitive wakeup. */ -void poll_wait_pipe(struct trace_iterator *iter) +int poll_wait_pipe(struct trace_iterator *iter) { set_current_state(TASK_INTERRUPTIBLE); /* sleep for 100 msecs, and try again. */ schedule_timeout(HZ / 10); + return 0; } /* Must be called with trace_types_lock mutex held. */ static int tracing_wait_pipe(struct file *filp) { struct trace_iterator *iter = filp->private_data; + int ret; while (trace_empty(iter)) { @@ -4181,10 +4182,13 @@ static int tracing_wait_pipe(struct file *filp) mutex_unlock(&iter->mutex); - iter->trace->wait_pipe(iter); + ret = iter->trace->wait_pipe(iter); mutex_lock(&iter->mutex); + if (ret) + return ret; + if (signal_pending(current)) return -EINTR; @@ -5112,8 +5116,12 @@ tracing_buffers_read(struct file *filp, char __user *ubuf, goto out_unlock; } mutex_unlock(&trace_types_lock); - iter->trace->wait_pipe(iter); + ret = iter->trace->wait_pipe(iter); mutex_lock(&trace_types_lock); + if (ret) { + size = ret; + goto out_unlock; + } if (signal_pending(current)) { size = -EINTR; goto out_unlock; @@ -5325,8 +5333,10 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos, goto out; } mutex_unlock(&trace_types_lock); - iter->trace->wait_pipe(iter); + ret = iter->trace->wait_pipe(iter); mutex_lock(&trace_types_lock); + if (ret) + goto out; if (signal_pending(current)) { ret = -EINTR; goto out; |