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
10 #include <afsconfig.h>
11 #include "afs/param.h"
14 #include "afs/sysincludes.h" /* Standard vendor system headers */
15 #include "afsincludes.h" /* Afs-based standard headers */
16 #include "afs/afs_stats.h" /* afs statistics */
18 #if defined(HAVE_LINUX_FREEZER_H)
19 #include <linux/freezer.h>
22 static char waitV, dummyV;
25 afs_osi_InitWaitHandle(struct afs_osi_WaitHandle *achandle)
27 AFS_STATCNT(osi_InitWaitHandle);
28 achandle->proc = (caddr_t) 0;
33 afs_osi_CancelWait(struct afs_osi_WaitHandle *achandle)
37 AFS_STATCNT(osi_CancelWait);
38 proc = achandle->proc;
41 achandle->proc = (caddr_t) 0; /* so dude can figure out he was signalled */
42 afs_osi_Wakeup(&waitV);
46 * Waits for data on ahandle, or ams ms later. ahandle may be null.
47 * Returns 0 if timeout and EINTR if signalled.
50 afs_osi_Wait(afs_int32 ams, struct afs_osi_WaitHandle *ahandle, int aintok)
55 AFS_STATCNT(osi_Wait);
56 endTime = osi_Time() + (ams / 1000);
58 ahandle->proc = (caddr_t) current;
62 code = afs_osi_TimedSleep(&waitV, ams, 1);
65 if (ahandle && (ahandle->proc == (caddr_t) 0)) {
66 /* we've been signalled */
69 } while (osi_Time() < endTime);
76 afs_event_t *afs_evhasht[AFS_EVHASHSIZE]; /* Hash table for events */
77 #define afs_evhash(event) (afs_uint32) ((((long)event)>>2) & (AFS_EVHASHSIZE-1));
78 int afs_evhashcnt = 0;
80 /* Get and initialize event structure corresponding to lwp event (i.e. address)
83 afs_getevent(char *event)
85 afs_event_t *evp, *newp = 0;
89 hashcode = afs_evhash(event);
90 evp = afs_evhasht[hashcode];
92 if (evp->event == event) {
96 if (evp->refcount == 0)
108 /* afs_addevent -- allocates a new event for the address. It isn't returned;
109 * instead, afs_getevent should be called again. Thus, the real effect of
110 * this routine is to add another event to the hash bucket for this
114 * Called with GLOCK held. However the function might drop
115 * GLOCK when it calls osi_AllocSmallSpace for allocating
116 * a new event (In Linux, the allocator drops GLOCK to avoid
121 afs_addevent(char *event)
127 hashcode = afs_evhash(event);
128 newp = osi_linux_alloc(sizeof(afs_event_t), 0);
130 newp->next = afs_evhasht[hashcode];
131 afs_evhasht[hashcode] = newp;
132 #if defined(AFS_LINUX24_ENV)
133 init_waitqueue_head(&newp->cond);
135 init_waitqueue(&newp->cond);
138 newp->event = &dummyV; /* Dummy address for new events */
142 #ifndef set_current_state
143 #define set_current_state(x) current->state = (x);
146 /* Release the specified event */
147 #define relevent(evp) ((evp)->refcount--)
151 * Waits for an event to be notified, returning early if a signal
152 * is received. Returns EINTR if signaled, and 0 otherwise.
155 afs_osi_SleepSig(void *event)
157 struct afs_event *evp;
159 #ifdef DECLARE_WAITQUEUE
160 DECLARE_WAITQUEUE(wait, current);
162 struct wait_queue wait = { current, NULL };
165 evp = afs_getevent(event);
168 evp = afs_getevent(event);
174 add_wait_queue(&evp->cond, &wait);
175 while (seq == evp->seq) {
176 set_current_state(TASK_INTERRUPTIBLE);
181 if (signal_pending(current)) {
186 remove_wait_queue(&evp->cond, &wait);
187 set_current_state(TASK_RUNNING);
193 /* afs_osi_Sleep -- waits for an event to be notified, ignoring signals.
194 * - NOTE: that on Linux, there are circumstances in which TASK_INTERRUPTIBLE
195 * can wake up, even if all signals are blocked
196 * - TODO: handle signals correctly by passing an indication back to the
197 * caller that the wait has been interrupted and the stack should be cleaned
198 * up preparatory to signal delivery
201 afs_osi_Sleep(void *event)
206 saved_set = current->blocked;
207 sigfillset(¤t->blocked);
208 RECALC_SIGPENDING(current);
211 afs_osi_SleepSig(event);
214 current->blocked = saved_set;
215 RECALC_SIGPENDING(current);
219 /* afs_osi_TimedSleep
222 * event - event to sleep on
223 * ams --- max sleep time in milliseconds
224 * aintok - 1 if should sleep interruptibly
226 * Returns 0 if timeout, EINTR if signalled, and EGAIN if it might
230 afs_osi_TimedSleep(void *event, afs_int32 ams, int aintok)
233 long ticks = (ams * HZ / 1000) + 1;
234 struct afs_event *evp;
235 #ifdef DECLARE_WAITQUEUE
236 DECLARE_WAITQUEUE(wait, current);
238 struct wait_queue wait = { current, NULL };
241 evp = afs_getevent(event);
244 evp = afs_getevent(event);
247 add_wait_queue(&evp->cond, &wait);
248 set_current_state(TASK_INTERRUPTIBLE);
249 /* always sleep TASK_INTERRUPTIBLE to keep load average
250 * from artifically increasing. */
254 if (schedule_timeout(ticks))
257 schedule_timeout(ticks);
260 remove_wait_queue(&evp->cond, &wait);
261 set_current_state(TASK_RUNNING);
270 afs_osi_Wakeup(void *event)
273 struct afs_event *evp;
275 evp = afs_getevent(event);
276 if (!evp) /* No sleepers */
279 if (evp->refcount > 1) {