Add new kernel probes instrumentation

[lttng-modules.git] / probes / lttng-probe-writeback.c

diff --git a/probes/lttng-probe-writeback.c b/probes/lttng-probe-writeback.c
new file mode 100644 (file)
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+++ b/probes/lttng-probe-writeback.c
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+/*
+ * probes/lttng-probe-writeback.c
+ *
+ * LTTng writeback probes.
+ *
+ * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * Copyright (C) 2012 Mentor Graphics Corp.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; only
+ * version 2.1 of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/mm.h>
+
+/*
+ * Create the tracepoint static inlines from the kernel to validate that our
+ * trace event macros match the kernel we run on.
+ */
+#include <trace/events/writeback.h>
+
+#include "../lttng-kernel-version.h"
+
+/* #if <check version number if global_dirty_limit will be exported> */
+#ifdef CONFIG_KALLSYMS
+#include "../wrapper/kallsyms.h"
+
+static unsigned long *wrapper_global_dirty_limit_sym = 0;
+static inline
+unsigned long wrapper_global_dirty_limit(void)
+{
+       if (!wrapper_global_dirty_limit_sym)
+               wrapper_global_dirty_limit_sym =
+                       (void *)kallsyms_lookup_funcptr("global_dirty_limit");
+       if (wrapper_global_dirty_limit_sym)
+               return *wrapper_global_dirty_limit_sym;
+       else {
+               printk(KERN_WARNING "LTTng: global_dirty_limit symbol lookup failed.\n");
+               return 0;
+       }
+}
+#define global_dirty_limit wrapper_global_dirty_limit()
+#endif
+/* #endif <check version number> */
+
+/*
+ * Create LTTng tracepoint probes.
+ */
+#define LTTNG_PACKAGE_BUILD
+#define CREATE_TRACE_POINTS
+#define TRACE_INCLUDE_PATH ../instrumentation/events/lttng-module
+
+#include "../instrumentation/events/lttng-module/writeback.h"
+
+MODULE_LICENSE("GPL and additional rights");
+MODULE_AUTHOR("Andrew Gabbasov <andrew_gabbasov@mentor.com>");
+MODULE_DESCRIPTION("LTTng writeback probes");