From c521efd1700a8c0f7ce26f011f5eaecca17fabfa Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Mon, 7 Dec 2009 09:06:24 -0500 Subject: tracing: Add pipe_close interface An ftrace plugin can add a pipe_open interface when the user opens trace_pipe. But if the plugin allocates something within the pipe_open it can not free it because there exists no pipe_close. The hook to the trace file open has a corresponding close. The closing of the trace_pipe file should also have a corresponding close. Signed-off-by: Steven Rostedt --- kernel/trace/trace.c | 4 ++++ kernel/trace/trace.h | 2 ++ 2 files changed, 6 insertions(+) (limited to 'kernel') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 874f2893cff..f804b407d43 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -2898,6 +2898,10 @@ static int tracing_release_pipe(struct inode *inode, struct file *file) else cpumask_clear_cpu(iter->cpu_file, tracing_reader_cpumask); + + if (iter->trace->pipe_open) + iter->trace->pipe_close(iter); + mutex_unlock(&trace_types_lock); free_cpumask_var(iter->started); diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 1d7f4830a80..7fa33cab696 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -272,6 +272,7 @@ struct tracer_flags { * @pipe_open: called when the trace_pipe file is opened * @wait_pipe: override how the user waits for traces on trace_pipe * @close: called when the trace file is released + * @pipe_close: called when the trace_pipe file is released * @read: override the default read callback on trace_pipe * @splice_read: override the default splice_read callback on trace_pipe * @selftest: selftest to run on boot (see trace_selftest.c) @@ -290,6 +291,7 @@ struct tracer { void (*pipe_open)(struct trace_iterator *iter); void (*wait_pipe)(struct trace_iterator *iter); void (*close)(struct trace_iterator *iter); + void (*pipe_close)(struct trace_iterator *iter); ssize_t (*read)(struct trace_iterator *iter, struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos); -- cgit v1.2.3