The code to update the print formats for events requires a vprintf
format in the trace_seq. This patch adds that interface.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Due to a cut and paste error, the trace_seq_putc had a semicolon
after the prototype but before the stub function when tracing is
disabled.
[Impact: fix compile error ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Due to a cut and paste error, I added the gcc attribute for printf
format to the static inline stub of trace_seq_printf.
This will cause a compile failure.
[ Impact: fix compiler error when CONFIG_TRACING is off ]
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: =?ISO-8859-15?Q?Fr=E9d=E9ric_Weisbecker?= <fweisbec@gmail.com>
LKML-Reference: <alpine.DEB.2.00.0904171717080.1016@gandalf.stny.rr.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: allow modules to add TRACE_EVENTS on load
This patch adds the final hooks to allow modules to use the TRACE_EVENT
macro. A notifier and a data structure are used to link the TRACE_EVENTs
defined in the module to connect them with the ftrace event tracing system.
It also adds the necessary automated clean ups to the trace events when a
module is removed.
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
In the process to make TRACE_EVENT macro work for modules, the trace_seq
operations must be available for core kernel code.
These operations are quite useful and can be used for other implementations.
The main idea is that we create a trace_seq handle that acts very much
like the seq_file handle.
struct trace_seq *s = kmalloc(sizeof(*s, GFP_KERNEL);
trace_seq_init(s);
trace_seq_printf(s, "some data %d\n", variable);
printk("%s", s->buffer);
The main use is to allow a top level function call several other functions
that may store printf like data into the buffer. Then at the end, the top
level function can process all the data with any method it would like to.
It could be passed to userspace, output via printk or even use seq_file:
trace_seq_to_user(s, ubuf, cnt);
seq_puts(m, s->buffer);
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Steven Rostedt