systemtap-common 1.6-1ubuntu1 / usr / share / systemtap / tapset / atomic.stp

// Atomic functions.
// Copyright (C) 2010 Red Hat Inc.
//
// This file is part of systemtap, and is free software.  You can
// redistribute it and/or modify it under the terms of the GNU General
// Public License (GPL); either version 2, or (at your option) any
// later version.

function atomic_read:long(addr:long)
%{ /* pure */
	atomic_t *a = (atomic_t *)(long)THIS->addr;

	/* We call deref() here to ensure the memory is valid to read.
	 * Note the result is thrown away, then we use the "real"
	 * atomic read function now that we know the address is safe. */
	(void)deref(sizeof(*a), a);
	THIS->__retvalue = atomic_read(a);
	CATCH_DEREF_FAULT();
%}

function atomic_long_read:long(addr:long)
%{ /* pure */
#ifdef ATOMIC_LONG_INIT
	atomic_long_t *a = (atomic_long_t *)(long)THIS->addr;

	/* We call deref() here to ensure the memory is valid to read.
	 * Note the result is thrown away, then we use the "real"
	 * atomic read function now that we know the address is safe. */
	(void)deref(sizeof(*a), a);
	THIS->__retvalue = atomic_long_read(a);
	CATCH_DEREF_FAULT();
#endif
%}