Commit 1155de47 authored by Paul Mundt's avatar Paul Mundt Committed by Ingo Molnar
Browse files

ring-buffer: Make it generally available 



In hunting down the cause for the hwlat_detector ring buffer spew in
my failed -next builds it became obvious that folks are now treating
ring_buffer as something that is generic independent of tracing and thus,
suitable for public driver consumption.

Given that there are only a few minor areas in ring_buffer that have any
reliance on CONFIG_TRACING or CONFIG_FUNCTION_TRACER, provide stubs for
those and make it generally available.

Signed-off-by: default avatarPaul Mundt <lethal@linux-sh.org>
Cc: Jon Masters <jcm@jonmasters.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20090625053012.GB19944@linux-sh.org>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 00e54d08

kernel/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -96,6 +96,7 @@ obj-$(CONFIG_HAVE_GENERIC_DMA_COHERENT) += dma-coherent.o 
obj-$(CONFIG_FUNCTION_TRACER) += trace/

obj-$(CONFIG_TRACING) += trace/

obj-$(CONFIG_X86_DS) += trace/

obj-$(CONFIG_RING_BUFFER) += trace/

obj-$(CONFIG_SMP) += sched_cpupri.o

obj-$(CONFIG_SLOW_WORK) += slow-work.o

obj-$(CONFIG_PERF_COUNTERS) += perf_counter.o

kernel/trace/ring_buffer.c

+11 −0
Original line number Diff line number Diff line
@@ -1563,6 +1563,8 @@ rb_reserve_next_event(struct ring_buffer_per_cpu *cpu_buffer, 
	return NULL;

}



#ifdef CONFIG_TRACING



#define TRACE_RECURSIVE_DEPTH 16



static int trace_recursive_lock(void)
@@ -1593,6 +1595,13 @@ static void trace_recursive_unlock(void) 
	current->trace_recursion--;

}



#else



#define trace_recursive_lock()		(0)

#define trace_recursive_unlock()	do { } while (0)



#endif



static DEFINE_PER_CPU(int, rb_need_resched);



/**
@@ -3104,6 +3113,7 @@ int ring_buffer_read_page(struct ring_buffer *buffer, 
}

EXPORT_SYMBOL_GPL(ring_buffer_read_page);



#ifdef CONFIG_TRACING

static ssize_t

rb_simple_read(struct file *filp, char __user *ubuf,

	       size_t cnt, loff_t *ppos)
@@ -3171,6 +3181,7 @@ static __init int rb_init_debugfs(void) 
}



fs_initcall(rb_init_debugfs);

#endif



#ifdef CONFIG_HOTPLUG_CPU

static int rb_cpu_notify(struct notifier_block *self,

kernel/trace/trace.h

+7 −0
Original line number Diff line number Diff line
@@ -597,6 +597,7 @@ print_graph_function(struct trace_iterator *iter) 


extern struct pid *ftrace_pid_trace;



#ifdef CONFIG_FUNCTION_TRACER

static inline int ftrace_trace_task(struct task_struct *task)

{

	if (!ftrace_pid_trace)
@@ -604,6 +605,12 @@ static inline int ftrace_trace_task(struct task_struct *task) 


	return test_tsk_trace_trace(task);

}

#else

static inline int ftrace_trace_task(struct task_struct *task)

{

	return 1;

}

#endif



/*

 * trace_iterator_flags is an enumeration that defines bit

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