1 files changed, 121 insertions, 0 deletions

diff --git a/include/linux/delayacct.h b/include/linux/delayacct.h
new file mode 100644
index 000000000000..561e2a77805c
--- /dev/null
+++ b/include/linux/delayacct.h
@@ -0,0 +1,121 @@
+/* delayacct.h - per-task delay accounting
+ *
+ * Copyright (C) Shailabh Nagar, IBM Corp. 2006
+ *
+ * This program is free software;  you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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 for more details.
+ *
+ */
+
+#ifndef _LINUX_DELAYACCT_H
+#define _LINUX_DELAYACCT_H
+
+#include <linux/sched.h>
+#include <linux/taskstats_kern.h>
+
+/*
+ * Per-task flags relevant to delay accounting
+ * maintained privately to avoid exhausting similar flags in sched.h:PF_*
+ * Used to set current->delays->flags
+ */
+#define DELAYACCT_PF_SWAPIN     0x00000001      /* I am doing a swapin */
+
+#ifdef CONFIG_TASK_DELAY_ACCT
+
+extern int delayacct_on;        /* Delay accounting turned on/off */
+extern kmem_cache_t *delayacct_cache;
+extern void delayacct_init(void);
+extern void __delayacct_tsk_init(struct task_struct *);
+extern void __delayacct_tsk_exit(struct task_struct *);
+extern void __delayacct_blkio_start(void);
+extern void __delayacct_blkio_end(void);
+extern int __delayacct_add_tsk(struct taskstats *, struct task_struct *);
+extern __u64 __delayacct_blkio_ticks(struct task_struct *);
+
+static inline void delayacct_set_flag(int flag)
+{
+        if (current->delays)
+                current->delays->flags |= flag;
+}
+
+static inline void delayacct_clear_flag(int flag)
+{
+        if (current->delays)
+                current->delays->flags &= ~flag;
+}
+
+static inline void delayacct_tsk_init(struct task_struct *tsk)
+{
+        /* reinitialize in case parent's non-null pointer was dup'ed*/
+        tsk->delays = NULL;
+        if (delayacct_on)
+                __delayacct_tsk_init(tsk);
+}
+
+/* Free tsk->delays. Called from bad fork and __put_task_struct
+ * where there's no risk of tsk->delays being accessed elsewhere
+ */
+static inline void delayacct_tsk_free(struct task_struct *tsk)
+{
+        if (tsk->delays)
+                kmem_cache_free(delayacct_cache, tsk->delays);
+        tsk->delays = NULL;
+}
+
+static inline void delayacct_blkio_start(void)
+{
+        if (current->delays)
+                __delayacct_blkio_start();
+}
+
+static inline void delayacct_blkio_end(void)
+{
+        if (current->delays)
+                __delayacct_blkio_end();
+}
+
+static inline int delayacct_add_tsk(struct taskstats *d,
+                                        struct task_struct *tsk)
+{
+        if (!delayacct_on || !tsk->delays)
+                return 0;
+        return __delayacct_add_tsk(d, tsk);
+}
+
+static inline __u64 delayacct_blkio_ticks(struct task_struct *tsk)
+{
+        if (tsk->delays)
+                return __delayacct_blkio_ticks(tsk);
+        return 0;
+}
+
+#else
+static inline void delayacct_set_flag(int flag)
+{}
+static inline void delayacct_clear_flag(int flag)
+{}
+static inline void delayacct_init(void)
+{}
+static inline void delayacct_tsk_init(struct task_struct *tsk)
+{}
+static inline void delayacct_tsk_free(struct task_struct *tsk)
+{}
+static inline void delayacct_blkio_start(void)
+{}
+static inline void delayacct_blkio_end(void)
+{}
+static inline int delayacct_add_tsk(struct taskstats *d,
+                                        struct task_struct *tsk)
+{ return 0; }
+static inline __u64 delayacct_blkio_ticks(struct task_struct *tsk)
+{ return 0; }
+#endif /* CONFIG_TASK_DELAY_ACCT */
+
+#endif