2 * Copyright 2000, International Business Machines Corporation and others.
5 * This software has been released under the terms of the IBM Public
6 * License. For details, see the LICENSE file in the top-level source
7 * directory or online at http://www.openafs.org/dl/license10.html
11 * rx_kmutex.c - mutex and condition variable macros for kernel environment.
13 * Linux implementation.
16 #include <afsconfig.h>
17 #include "afs/param.h"
22 #include "rx/rx_kcommon.h"
23 #include "rx_kmutex.h"
24 #include "rx/rx_kernel.h"
27 afs_mutex_init(afs_kmutex_t * l)
29 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,16)
30 mutex_init(&l->mutex);
31 #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,0)
40 afs_mutex_enter(afs_kmutex_t * l)
42 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,16)
43 mutex_lock(&l->mutex);
48 osi_Panic("mutex_enter: 0x%x held by %d", l, l->owner);
49 l->owner = current->pid;
53 afs_mutex_tryenter(afs_kmutex_t * l)
55 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,16)
56 if (mutex_trylock(&l->mutex) == 0)
58 if (down_trylock(&l->sem))
61 l->owner = current->pid;
66 afs_mutex_exit(afs_kmutex_t * l)
68 if (l->owner != current->pid)
69 osi_Panic("mutex_exit: 0x%x held by %d", l, l->owner);
71 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,16)
72 mutex_unlock(&l->mutex);
78 /* CV_WAIT and CV_TIMEDWAIT sleep until the specified event occurs, or, in the
79 * case of CV_TIMEDWAIT, until the specified timeout occurs.
80 * - NOTE: that on Linux, there are circumstances in which TASK_INTERRUPTIBLE
81 * can wake up, even if all signals are blocked
82 * - TODO: handle signals correctly by passing an indication back to the
83 * caller that the wait has been interrupted and the stack should be cleaned
84 * up preparatory to signal delivery
87 afs_cv_wait(afs_kcondvar_t * cv, afs_kmutex_t * l, int sigok)
89 int seq, isAFSGlocked = ISAFS_GLOCK();
91 #ifdef DECLARE_WAITQUEUE
92 DECLARE_WAITQUEUE(wait, current);
94 struct wait_queue wait = { current, NULL };
99 set_current_state(TASK_INTERRUPTIBLE);
100 add_wait_queue(&cv->waitq, &wait);
108 saved_set = current->blocked;
109 sigfillset(¤t->blocked);
110 RECALC_SIGPENDING(current);
114 while(seq == cv->seq) {
116 #ifdef AFS_LINUX26_ENV
120 current->flags & PF_FREEZE
125 #ifdef LINUX_REFRIGERATOR_TAKES_PF_FREEZE
126 refrigerator(PF_FREEZE);
130 set_current_state(TASK_INTERRUPTIBLE);
135 remove_wait_queue(&cv->waitq, &wait);
136 set_current_state(TASK_RUNNING);
140 current->blocked = saved_set;
141 RECALC_SIGPENDING(current);
149 return (sigok && signal_pending(current)) ? EINTR : 0;
153 afs_cv_timedwait(afs_kcondvar_t * cv, afs_kmutex_t * l, int waittime)
155 int seq, isAFSGlocked = ISAFS_GLOCK();
156 long t = waittime * HZ / 1000;
157 #ifdef DECLARE_WAITQUEUE
158 DECLARE_WAITQUEUE(wait, current);
160 struct wait_queue wait = { current, NULL };
164 set_current_state(TASK_INTERRUPTIBLE);
165 add_wait_queue(&cv->waitq, &wait);
171 while(seq == cv->seq) {
172 t = schedule_timeout(t);
173 if (!t) /* timeout */
177 remove_wait_queue(&cv->waitq, &wait);
178 set_current_state(TASK_RUNNING);