Move all sources to 'src/'

[lttng-ust.git] / src / libringbuffer / smp.h

diff --git a/src/libringbuffer/smp.h b/src/libringbuffer/smp.h
new file mode 100644 (file)
index 0000000..028a66f
--- /dev/null
+++ b/src/libringbuffer/smp.h
@@ -0,0 +1,35 @@
+/*
+ * SPDX-License-Identifier: LGPL-2.1-only
+ *
+ * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ */
+
+#ifndef _LIBRINGBUFFER_SMP_H
+#define _LIBRINGBUFFER_SMP_H
+
+#include "getcpu.h"
+
+/*
+ * 4kB of per-cpu data available. Enough to hold the control structures,
+ * but not ring buffers.
+ */
+#define PER_CPU_MEM_SIZE       4096
+
+extern int __num_possible_cpus
+       __attribute__((visibility("hidden")));
+
+extern void _get_num_possible_cpus(void)
+       __attribute__((visibility("hidden")));
+
+static inline
+int num_possible_cpus(void)
+{
+       if (!__num_possible_cpus)
+               _get_num_possible_cpus();
+       return __num_possible_cpus;
+}
+
+#define for_each_possible_cpu(cpu)             \
+       for ((cpu) = 0; (cpu) < num_possible_cpus(); (cpu)++)
+
+#endif /* _LIBRINGBUFFER_SMP_H */