From: Francis Giraldeau <francis.giraldeau@gmail.com>
Date: Wed, 3 Sep 2014 19:47:21 +0000 (-0400)
Subject: Define max nesting count constant
X-Git-Tag: v2.11.0-rc1~34
X-Git-Url: http://git.lttng.org/?p=lttng-modules.git;a=commitdiff_plain;h=b055caba03c71b621bff8ec9caa0e041ac6489a9

Define max nesting count constant

Extract the constant within the code as #define. The define is added to
frontend.h in order to be included in other source files.

Signed-off-by: Francis Giraldeau <francis.giraldeau@gmail.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---

diff --git a/lib/ringbuffer/frontend.h b/lib/ringbuffer/frontend.h
index 1450cb7f..ba96d9a6 100644
--- a/lib/ringbuffer/frontend.h
+++ b/lib/ringbuffer/frontend.h
@@ -51,6 +51,9 @@
 /* Internal helpers */
 #include <wrapper/ringbuffer/frontend_internal.h>
 
+/* Max ring buffer nesting count, see lib_ring_buffer_get_cpu(). */
+#define RING_BUFFER_MAX_NESTING 4
+
 /* Buffer creation/removal and setup operations */
 
 /*
diff --git a/lib/ringbuffer/frontend_api.h b/lib/ringbuffer/frontend_api.h
index 23118c46..b4a8db89 100644
--- a/lib/ringbuffer/frontend_api.h
+++ b/lib/ringbuffer/frontend_api.h
@@ -58,7 +58,7 @@ int lib_ring_buffer_get_cpu(const struct lib_ring_buffer_config *config)
 	nesting = ++per_cpu(lib_ring_buffer_nesting, cpu);
 	barrier();
 
-	if (unlikely(nesting > 4)) {
+	if (unlikely(nesting > RING_BUFFER_MAX_NESTING)) {
 		WARN_ON_ONCE(1);
 		per_cpu(lib_ring_buffer_nesting, cpu)--;
 		rcu_read_unlock_sched_notrace();