+/*
+ * This file is part of the SPL: Solaris Porting Layer.
+ *
+ * Copyright (c) 2008 Lawrence Livermore National Security, LLC.
+ * Produced at Lawrence Livermore National Laboratory
+ * Written by:
+ * Brian Behlendorf <behlendorf1@llnl.gov>,
+ * Herb Wartens <wartens2@llnl.gov>,
+ * Jim Garlick <garlick@llnl.gov>
+ * UCRL-CODE-235197
+ *
+ * This 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 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.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
#ifndef _SPL_CONDVAR_H
#define _SPL_CONDVAR_H
#include <linux/module.h>
#include <linux/wait.h>
+#include <sys/kmem.h>
+#include <sys/mutex.h>
/* The kcondvar_t struct is protected by mutex taken externally before
* calling any of the wait/signal funs, and passed into the wait funs.
typedef struct {
int cv_magic;
char *cv_name;
+ int cv_name_size;
wait_queue_head_t cv_event;
atomic_t cv_waiters;
- kmutex_t *cv_mutex; /* only for verification purposes */
+ kmutex_t *cv_mutex;
+ spinlock_t cv_lock;
} kcondvar_t;
typedef enum { CV_DEFAULT=0, CV_DRIVER } kcv_type_t;
-static __inline__ void
-cv_init(kcondvar_t *cvp, char *name, kcv_type_t type, void *arg)
-{
- BUG_ON(cvp == NULL);
- BUG_ON(type != CV_DEFAULT);
- BUG_ON(arg != NULL);
-
- cvp->cv_magic = CV_MAGIC;
- init_waitqueue_head(&cvp->cv_event);
- atomic_set(&cvp->cv_waiters, 0);
- cvp->cv_mutex = NULL;
- cvp->cv_name = NULL;
-
- if (name) {
- cvp->cv_name = kmalloc(strlen(name) + 1, GFP_KERNEL);
- if (cvp->cv_name)
- strcpy(cvp->cv_name, name);
- }
-}
-
-static __inline__ void
-cv_destroy(kcondvar_t *cvp)
-{
- BUG_ON(cvp == NULL);
- BUG_ON(cvp->cv_magic != CV_MAGIC);
- BUG_ON(atomic_read(&cvp->cv_waiters) != 0);
- BUG_ON(waitqueue_active(&cvp->cv_event));
-
- if (cvp->cv_name)
- kfree(cvp->cv_name);
-
- memset(cvp, CV_POISON, sizeof(*cvp));
-}
-
-static __inline__ void
-cv_wait(kcondvar_t *cvp, kmutex_t *mtx)
-{
- DEFINE_WAIT(wait);
- int flag = 1;
-
- BUG_ON(cvp == NULL || mtx == NULL);
- BUG_ON(cvp->cv_magic != CV_MAGIC);
- BUG_ON(!mutex_owned(mtx));
-
- if (cvp->cv_mutex == NULL)
- cvp->cv_mutex = mtx;
-
- /* Ensure the same mutex is used by all callers */
- BUG_ON(cvp->cv_mutex != mtx);
-
- for (;;) {
- prepare_to_wait_exclusive(&cvp->cv_event, &wait,
- TASK_INTERRUPTIBLE);
- /* Must occur after we are added to the list but only once */
- if (flag) {
- atomic_inc(&cvp->cv_waiters);
- flag = 0;
- }
-
- /* XXX - The correct thing to do here may be to wake up and
- * force the caller to handle the signal. Spurious wakeups
- * should already be safely handled by the caller. */
- if (signal_pending(current))
- flush_signals(current);
-
- /* Mutex should be dropped after prepare_to_wait() this
- * ensures we're linked in to the waiters list and avoids the
- * race where 'cvp->cv_waiters > 0' but the list is empty. */
- mutex_exit(mtx);
- schedule();
- mutex_enter(mtx);
-
- /* XXX - The correct thing to do here may be to wake up and
- * force the caller to handle the signal. Spurious wakeups
- * should already be safely handled by the caller. */
- if (signal_pending(current))
- continue;
-
- break;
- }
-
- atomic_dec(&cvp->cv_waiters);
- finish_wait(&cvp->cv_event, &wait);
-}
-
-/* 'expire_time' argument is an absolute wall clock time in jiffies.
- * Return value is time left (expire_time - now) or -1 if timeout occurred.
- */
-static __inline__ clock_t
-cv_timedwait(kcondvar_t *cvp, kmutex_t *mtx, clock_t expire_time)
-{
- DEFINE_WAIT(wait);
- clock_t time_left;
- int flag = 1;
-
- BUG_ON(cvp == NULL || mtx == NULL);
- BUG_ON(cvp->cv_magic != CV_MAGIC);
- BUG_ON(!mutex_owned(mtx));
-
- if (cvp->cv_mutex == NULL)
- cvp->cv_mutex = mtx;
-
- /* XXX - Does not handle jiffie wrap properly */
- time_left = expire_time - jiffies;
- if (time_left <= 0)
- return -1;
-
- /* Ensure the same mutex is used by all callers */
- BUG_ON(cvp->cv_mutex != mtx);
-
- for (;;) {
- prepare_to_wait_exclusive(&cvp->cv_event, &wait,
- TASK_INTERRUPTIBLE);
- if (flag) {
- atomic_inc(&cvp->cv_waiters);
- flag = 0;
- }
-
- /* XXX - The correct thing to do here may be to wake up and
- * force the caller to handle the signal. Spurious wakeups
- * should already be safely handled by the caller. */
- if (signal_pending(current))
- flush_signals(current);
-
- /* Mutex should be dropped after prepare_to_wait() this
- * ensures we're linked in to the waiters list and avoids the
- * race where 'cvp->cv_waiters > 0' but the list is empty. */
- mutex_exit(mtx);
- time_left = schedule_timeout(time_left);
- mutex_enter(mtx);
-
- /* XXX - The correct thing to do here may be to wake up and
- * force the caller to handle the signal. Spurious wakeups
- * should already be safely handled by the caller. */
- if (signal_pending(current)) {
- if (time_left > 0)
- continue;
-
- flush_signals(current);
- }
-
- break;
- }
-
- atomic_dec(&cvp->cv_waiters);
- finish_wait(&cvp->cv_event, &wait);
-
- return (time_left > 0 ? time_left : -1);
-}
-
-static __inline__ void
-cv_signal(kcondvar_t *cvp)
-{
- BUG_ON(cvp == NULL);
- BUG_ON(cvp->cv_magic != CV_MAGIC);
-
- /* All waiters are added with WQ_FLAG_EXCLUSIVE so only one
- * waiter will be set runable with each call to wake_up().
- * Additionally wake_up() holds a spin_lock assoicated with
- * the wait queue to ensure we don't race waking up processes. */
- if (atomic_read(&cvp->cv_waiters) > 0)
- wake_up(&cvp->cv_event);
-}
-
-static __inline__ void
-cv_broadcast(kcondvar_t *cvp)
-{
- BUG_ON(cvp == NULL);
- BUG_ON(cvp->cv_magic != CV_MAGIC);
+extern void __cv_init(kcondvar_t *cvp, char *name, kcv_type_t type, void *arg);
+extern void __cv_destroy(kcondvar_t *cvp);
+extern void __cv_wait(kcondvar_t *cvp, kmutex_t *mp);
+extern clock_t __cv_timedwait(kcondvar_t *cvp, kmutex_t *mp,
+ clock_t expire_time);
+extern void __cv_signal(kcondvar_t *cvp);
+extern void __cv_broadcast(kcondvar_t *cvp);
+
+#define cv_init(cvp, name, type, arg) \
+({ \
+ if ((name) == NULL) \
+ __cv_init(cvp, #cvp, type, arg); \
+ else \
+ __cv_init(cvp, name, type, arg); \
+})
+#define cv_destroy(cvp) __cv_destroy(cvp)
+#define cv_wait(cvp, mp) __cv_wait(cvp, mp)
+#define cv_timedwait(cvp, mp, t) __cv_timedwait(cvp, mp, t)
+#define cv_signal(cvp) __cv_signal(cvp)
+#define cv_broadcast(cvp) __cv_broadcast(cvp)
- /* Wake_up_all() will wake up all waiters even those which
- * have the WQ_FLAG_EXCLUSIVE flag set. */
- if (atomic_read(&cvp->cv_waiters) > 0)
- wake_up_all(&cvp->cv_event);
-}
#endif /* _SPL_CONDVAR_H */
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