Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / staging / lustre / lustre / libcfs / fail.c

diff --git a/kernel/drivers/staging/lustre/lustre/libcfs/fail.c b/kernel/drivers/staging/lustre/lustre/libcfs/fail.c
new file mode 100644 (file)
index 0000000..92444b0
--- /dev/null
+++ b/kernel/drivers/staging/lustre/lustre/libcfs/fail.c
@@ -0,0 +1,138 @@
+/*
+ * GPL HEADER START
+ *
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 only,
+ * as published by the Free Software Foundation.
+ *
+ * This program 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
+ * General Public License version 2 for more details (a copy is included
+ * in the LICENSE file that accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License
+ * version 2 along with this program; If not, see http://www.gnu.org/licenses
+ *
+ * Please contact Oracle Corporation, Inc., 500 Oracle Parkway, Redwood Shores,
+ * CA 94065 USA or visit www.oracle.com if you need additional information or
+ * have any questions.
+ *
+ * GPL HEADER END
+ */
+/*
+ * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Use is subject to license terms.
+ *
+ * Copyright (c) 2011, 2012, Intel Corporation.
+ */
+/*
+ * This file is part of Lustre, http://www.lustre.org/
+ * Lustre is a trademark of Oracle Corporation, Inc.
+ */
+
+#include "../../include/linux/libcfs/libcfs.h"
+
+unsigned long cfs_fail_loc = 0;
+EXPORT_SYMBOL(cfs_fail_loc);
+
+unsigned int cfs_fail_val = 0;
+EXPORT_SYMBOL(cfs_fail_val);
+
+wait_queue_head_t cfs_race_waitq;
+EXPORT_SYMBOL(cfs_race_waitq);
+
+int cfs_race_state;
+EXPORT_SYMBOL(cfs_race_state);
+
+int __cfs_fail_check_set(__u32 id, __u32 value, int set)
+{
+       static atomic_t cfs_fail_count = ATOMIC_INIT(0);
+
+       LASSERT(!(id & CFS_FAIL_ONCE));
+
+       if ((cfs_fail_loc & (CFS_FAILED | CFS_FAIL_ONCE)) ==
+           (CFS_FAILED | CFS_FAIL_ONCE)) {
+               atomic_set(&cfs_fail_count, 0); /* paranoia */
+               return 0;
+       }
+
+       /* Fail 1/cfs_fail_val times */
+       if (cfs_fail_loc & CFS_FAIL_RAND) {
+               if (cfs_fail_val < 2 || cfs_rand() % cfs_fail_val > 0)
+                       return 0;
+       }
+
+       /* Skip the first cfs_fail_val, then fail */
+       if (cfs_fail_loc & CFS_FAIL_SKIP) {
+               if (atomic_inc_return(&cfs_fail_count) <= cfs_fail_val)
+                       return 0;
+       }
+
+       /* check cfs_fail_val... */
+       if (set == CFS_FAIL_LOC_VALUE) {
+               if (cfs_fail_val != -1 && cfs_fail_val != value)
+                       return 0;
+       }
+
+       /* Fail cfs_fail_val times, overridden by FAIL_ONCE */
+       if (cfs_fail_loc & CFS_FAIL_SOME &&
+           (!(cfs_fail_loc & CFS_FAIL_ONCE) || cfs_fail_val <= 1)) {
+               int count = atomic_inc_return(&cfs_fail_count);
+
+               if (count >= cfs_fail_val) {
+                       set_bit(CFS_FAIL_ONCE_BIT, &cfs_fail_loc);
+                       atomic_set(&cfs_fail_count, 0);
+                       /* we are lost race to increase  */
+                       if (count > cfs_fail_val)
+                               return 0;
+               }
+       }
+
+       if ((set == CFS_FAIL_LOC_ORSET || set == CFS_FAIL_LOC_RESET) &&
+           (value & CFS_FAIL_ONCE))
+               set_bit(CFS_FAIL_ONCE_BIT, &cfs_fail_loc);
+       /* Lost race to set CFS_FAILED_BIT. */
+       if (test_and_set_bit(CFS_FAILED_BIT, &cfs_fail_loc)) {
+               /* If CFS_FAIL_ONCE is valid, only one process can fail,
+                * otherwise multi-process can fail at the same time. */
+               if (cfs_fail_loc & CFS_FAIL_ONCE)
+                       return 0;
+       }
+
+       switch (set) {
+       case CFS_FAIL_LOC_NOSET:
+       case CFS_FAIL_LOC_VALUE:
+               break;
+       case CFS_FAIL_LOC_ORSET:
+               cfs_fail_loc |= value & ~(CFS_FAILED | CFS_FAIL_ONCE);
+               break;
+       case CFS_FAIL_LOC_RESET:
+               cfs_fail_loc = value;
+               break;
+       default:
+               LASSERTF(0, "called with bad set %u\n", set);
+               break;
+       }
+
+       return 1;
+}
+EXPORT_SYMBOL(__cfs_fail_check_set);
+
+int __cfs_fail_timeout_set(__u32 id, __u32 value, int ms, int set)
+{
+       int ret = 0;
+
+       ret = __cfs_fail_check_set(id, value, set);
+       if (ret) {
+               CERROR("cfs_fail_timeout id %x sleeping for %dms\n",
+                      id, ms);
+               set_current_state(TASK_UNINTERRUPTIBLE);
+               schedule_timeout(cfs_time_seconds(ms) / 1000);
+               CERROR("cfs_fail_timeout id %x awake\n", id);
+       }
+       return ret;
+}
+EXPORT_SYMBOL(__cfs_fail_timeout_set);