-/* $Id: fasttimer.c,v 1.9 2005/03/04 08:16:16 starvik Exp $
+/*
* linux/arch/cris/kernel/fasttimer.c
*
* Fast timers for ETRAX100/ETRAX100LX
- * This may be useful in other OS than Linux so use 2 space indentation...
*
- * $Log: fasttimer.c,v $
- * Revision 1.9 2005/03/04 08:16:16 starvik
- * Merge of Linux 2.6.11.
- *
- * Revision 1.8 2005/01/05 06:09:29 starvik
- * cli()/sti() will be obsolete in 2.6.11.
- *
- * Revision 1.7 2005/01/03 13:35:46 starvik
- * Removed obsolete stuff.
- * Mark fast timer IRQ as not shared.
- *
- * Revision 1.6 2004/05/14 10:18:39 starvik
- * Export fast_timer_list
- *
- * Revision 1.5 2004/05/14 07:58:01 starvik
- * Merge of changes from 2.4
- *
- * Revision 1.4 2003/07/04 08:27:41 starvik
- * Merge of Linux 2.5.74
- *
- * Revision 1.3 2002/12/12 08:26:32 starvik
- * Don't use C-comments inside CVS comments
- *
- * Revision 1.2 2002/12/11 15:42:02 starvik
- * Extracted v10 (ETRAX 100LX) specific stuff from arch/cris/kernel/
- *
- * Revision 1.1 2002/11/18 07:58:06 starvik
- * Fast timers (from Linux 2.4)
- *
- * Revision 1.5 2002/10/15 06:21:39 starvik
- * Added call to init_waitqueue_head
- *
- * Revision 1.4 2002/05/28 17:47:59 johana
- * Added del_fast_timer()
- *
- * Revision 1.3 2002/05/28 16:16:07 johana
- * Handle empty fast_timer_list
- *
- * Revision 1.2 2002/05/27 15:38:42 johana
- * Made it compile without warnings on Linux 2.4.
- * (includes, wait_queue, PROC_FS and snprintf)
- *
- * Revision 1.1 2002/05/27 15:32:25 johana
- * arch/etrax100/kernel/fasttimer.c v1.8 from the elinux tree.
- *
- * Revision 1.8 2001/11/27 13:50:40 pkj
- * Disable interrupts while stopping the timer and while modifying the
- * list of active timers in timer1_handler() as it may be interrupted
- * by other interrupts (e.g., the serial interrupt) which may add fast
- * timers.
- *
- * Revision 1.7 2001/11/22 11:50:32 pkj
- * * Only store information about the last 16 timers.
- * * proc_fasttimer_read() now uses an allocated buffer, since it
- * requires more space than just a page even for only writing the
- * last 16 timers. The buffer is only allocated on request, so
- * unless /proc/fasttimer is read, it is never allocated.
- * * Renamed fast_timer_started to fast_timers_started to match
- * fast_timers_added and fast_timers_expired.
- * * Some clean-up.
- *
- * Revision 1.6 2000/12/13 14:02:08 johana
- * Removed volatile for fast_timer_list
- *
- * Revision 1.5 2000/12/13 13:55:35 johana
- * Added DEBUG_LOG, added som cli() and cleanup
- *
- * Revision 1.4 2000/12/05 13:48:50 johana
- * Added range check when writing proc file, modified timer int handling
- *
- * Revision 1.3 2000/11/23 10:10:20 johana
- * More debug/logging possibilities.
- * Moved GET_JIFFIES_USEC() to timex.h and time.c
- *
- * Revision 1.2 2000/11/01 13:41:04 johana
- * Clean up and bugfixes.
- * Created new do_gettimeofday_fast() that gets a timeval struct
- * with time based on jiffies and *R_TIMER0_DATA, uses a table
- * for fast conversion of timer value to microseconds.
- * (Much faster the standard do_gettimeofday() and we don't really
- * want to use the true time - we want the "uptime" so timers don't screw up
- * when we change the time.
- * TODO: Add efficient support for continuous timers as well.
- *
- * Revision 1.1 2000/10/26 15:49:16 johana
- * Added fasttimer, highresolution timers.
- *
- * Copyright (C) 2000,2001 2002 Axis Communications AB, Lund, Sweden
+ * Copyright (C) 2000-2007 Axis Communications AB, Lund, Sweden
*/
#include <linux/errno.h>
#ifdef FAST_TIMER_SANITY_CHECKS
#define SANITYCHECK(x) x
-static int sanity_failed = 0;
+static int sanity_failed;
#else
#define SANITYCHECK(x)
#endif
#define __INLINE__ inline
-static int fast_timer_running = 0;
-static int fast_timers_added = 0;
-static int fast_timers_started = 0;
-static int fast_timers_expired = 0;
-static int fast_timers_deleted = 0;
-static int fast_timer_is_init = 0;
-static int fast_timer_ints = 0;
+static unsigned int fast_timer_running;
+static unsigned int fast_timers_added;
+static unsigned int fast_timers_started;
+static unsigned int fast_timers_expired;
+static unsigned int fast_timers_deleted;
+static unsigned int fast_timer_is_init;
+static unsigned int fast_timer_ints;
struct fast_timer *fast_timer_list = NULL;
#define DEBUG_LOG_MAX 128
static const char * debug_log_string[DEBUG_LOG_MAX];
static unsigned long debug_log_value[DEBUG_LOG_MAX];
-static int debug_log_cnt = 0;
-static int debug_log_cnt_wrapped = 0;
+static unsigned int debug_log_cnt;
+static unsigned int debug_log_cnt_wrapped;
#define DEBUG_LOG(string, value) \
{ \
int timer_delay_settings[NUM_TIMER_STATS];
/* Not true gettimeofday, only checks the jiffies (uptime) + useconds */
-void __INLINE__ do_gettimeofday_fast(struct timeval *tv)
+void __INLINE__ do_gettimeofday_fast(struct fasttime_t *tv)
{
- unsigned long sec = jiffies;
- unsigned long usec = GET_JIFFIES_USEC();
-
- usec += (sec % HZ) * (1000000 / HZ);
- sec = sec / HZ;
-
- if (usec > 1000000)
- {
- usec -= 1000000;
- sec++;
- }
- tv->tv_sec = sec;
- tv->tv_usec = usec;
+ tv->tv_jiff = jiffies;
+ tv->tv_usec = GET_JIFFIES_USEC();
}
-int __INLINE__ timeval_cmp(struct timeval *t0, struct timeval *t1)
+int __INLINE__ timeval_cmp(struct fasttime_t *t0, struct fasttime_t *t1)
{
- if (t0->tv_sec < t1->tv_sec)
- {
- return -1;
- }
- else if (t0->tv_sec > t1->tv_sec)
- {
- return 1;
- }
- if (t0->tv_usec < t1->tv_usec)
- {
- return -1;
- }
- else if (t0->tv_usec > t1->tv_usec)
- {
- return 1;
- }
- return 0;
+ /* Compare jiffies. Takes care of wrapping */
+ if (time_before(t0->tv_jiff, t1->tv_jiff))
+ return -1;
+ else if (time_after(t0->tv_jiff, t1->tv_jiff))
+ return 1;
+
+ /* Compare us */
+ if (t0->tv_usec < t1->tv_usec)
+ return -1;
+ else if (t0->tv_usec > t1->tv_usec)
+ return 1;
+ return 0;
}
void __INLINE__ start_timer1(unsigned long delay_us)
timer_freq_settings[fast_timers_started % NUM_TIMER_STATS] = freq_index;
timer_delay_settings[fast_timers_started % NUM_TIMER_STATS] = delay_us;
- D1(printk("start_timer1 : %d us freq: %i div: %i\n",
+ D1(printk(KERN_DEBUG "start_timer1 : %d us freq: %i div: %i\n",
delay_us, freq_index, div));
/* Clear timer1 irq */
*R_IRQ_MASK0_CLR = IO_STATE(R_IRQ_MASK0_CLR, timer1, clr);
printk(KERN_WARNING
"timer name: %s data: 0x%08lX already in list!\n", name, data);
sanity_failed++;
- return;
+ goto done;
}
else
{
t->name = name;
t->tv_expires.tv_usec = t->tv_set.tv_usec + delay_us % 1000000;
- t->tv_expires.tv_sec = t->tv_set.tv_sec + delay_us / 1000000;
+ t->tv_expires.tv_jiff = t->tv_set.tv_jiff + delay_us / 1000000 / HZ;
if (t->tv_expires.tv_usec > 1000000)
{
t->tv_expires.tv_usec -= 1000000;
- t->tv_expires.tv_sec++;
+ t->tv_expires.tv_jiff += HZ;
}
#ifdef FAST_TIMER_LOG
timer_added_log[fast_timers_added % NUM_TIMER_STATS] = *t;
D2(printk("start_one_shot_timer: %d us done\n", delay_us));
+done:
local_irq_restore(flags);
} /* start_one_shot_timer */
/* Timer 1 interrupt handler */
static irqreturn_t
-timer1_handler(int irq, void *dev_id, struct pt_regs *regs)
+timer1_handler(int irq, void *dev_id)
{
struct fast_timer *t;
unsigned long flags;
+ /* We keep interrupts disabled not only when we modify the
+ * fast timer list, but any time we hold a reference to a
+ * timer in the list, since del_fast_timer may be called
+ * from (another) interrupt context. Thus, the only time
+ * when interrupts are enabled is when calling the timer
+ * callback function.
+ */
local_irq_save(flags);
/* Clear timer1 irq */
fast_timer_running = 0;
fast_timer_ints++;
- local_irq_restore(flags);
-
t = fast_timer_list;
while (t)
{
- struct timeval tv;
+ struct fasttime_t tv;
+ fast_timer_function_type *f;
+ unsigned long d;
/* Has it really expired? */
do_gettimeofday_fast(&tv);
- D1(printk("t: %is %06ius\n", tv.tv_sec, tv.tv_usec));
+ D1(printk(KERN_DEBUG "t: %is %06ius\n",
+ tv.tv_jiff, tv.tv_usec));
if (timeval_cmp(&t->tv_expires, &tv) <= 0)
{
fast_timers_expired++;
/* Remove this timer before call, since it may reuse the timer */
- local_irq_save(flags);
if (t->prev)
{
t->prev->next = t->next;
}
t->prev = NULL;
t->next = NULL;
- local_irq_restore(flags);
- if (t->function != NULL)
- {
- t->function(t->data);
- }
- else
- {
+ /* Save function callback data before enabling
+ * interrupts, since the timer may be removed and
+ * we don't know how it was allocated
+ * (e.g. ->function and ->data may become overwritten
+ * after deletion if the timer was stack-allocated).
+ */
+ f = t->function;
+ d = t->data;
+
+ if (f != NULL) {
+ /* Run callback with interrupts enabled. */
+ local_irq_restore(flags);
+ f(d);
+ local_irq_save(flags);
+ } else
DEBUG_LOG("!timer1 %i function==NULL!\n", fast_timer_ints);
- }
}
else
{
D1(printk(".\n"));
}
- local_irq_save(flags);
if ((t = fast_timer_list) != NULL)
{
/* Start next timer.. */
- long us;
- struct timeval tv;
+ long us = 0;
+ struct fasttime_t tv;
do_gettimeofday_fast(&tv);
- us = ((t->tv_expires.tv_sec - tv.tv_sec) * 1000000 +
- t->tv_expires.tv_usec - tv.tv_usec);
+
+ /* time_after_eq takes care of wrapping */
+ if (time_after_eq(t->tv_expires.tv_jiff, tv.tv_jiff))
+ us = ((t->tv_expires.tv_jiff - tv.tv_jiff) *
+ 1000000 / HZ + t->tv_expires.tv_usec -
+ tv.tv_usec);
+
if (us > 0)
{
if (!fast_timer_running)
#endif
start_timer1(us);
}
- local_irq_restore(flags);
break;
}
else
D1(printk("e! %d\n", us));
}
}
- local_irq_restore(flags);
}
+ local_irq_restore(flags);
+
if (!t)
{
D1(printk("t1 stop!\n"));
void schedule_usleep(unsigned long us)
{
struct fast_timer t;
-#ifdef DECLARE_WAITQUEUE
wait_queue_head_t sleep_wait;
init_waitqueue_head(&sleep_wait);
- {
- DECLARE_WAITQUEUE(wait, current);
-#else
- struct wait_queue *sleep_wait = NULL;
- struct wait_queue wait = { current, NULL };
-#endif
D1(printk("schedule_usleep(%d)\n", us));
- add_wait_queue(&sleep_wait, &wait);
- set_current_state(TASK_INTERRUPTIBLE);
start_one_shot_timer(&t, wake_up_func, (unsigned long)&sleep_wait, us,
"usleep");
- schedule();
- set_current_state(TASK_RUNNING);
- remove_wait_queue(&sleep_wait, &wait);
+ /* Uninterruptible sleep on the fast timer. (The condition is somewhat
+ * redundant since the timer is what wakes us up.) */
+ wait_event(sleep_wait, !fast_timer_pending(&t));
+
D1(printk("done schedule_usleep(%d)\n", us));
-#ifdef DECLARE_WAITQUEUE
- }
-#endif
}
#ifdef CONFIG_PROC_FS
unsigned long flags;
int i = 0;
int num_to_show;
- struct timeval tv;
+ struct fasttime_t tv;
struct fast_timer *t, *nextt;
static char *bigbuf = NULL;
static unsigned long used;
if (!bigbuf && !(bigbuf = vmalloc(BIG_BUF_SIZE)))
{
used = 0;
- bigbuf[0] = '\0';
+ if (buf)
+ buf[0] = '\0';
return 0;
}
used += sprintf(bigbuf + used, "Fast timer running: %s\n",
fast_timer_running ? "yes" : "no");
used += sprintf(bigbuf + used, "Current time: %lu.%06lu\n",
- (unsigned long)tv.tv_sec,
+ (unsigned long)tv.tv_jiff,
(unsigned long)tv.tv_usec);
#ifdef FAST_TIMER_SANITY_CHECKS
used += sprintf(bigbuf + used, "Sanity failed: %i\n",
"d: %6li us data: 0x%08lX"
"\n",
t->name,
- (unsigned long)t->tv_set.tv_sec,
+ (unsigned long)t->tv_set.tv_jiff,
(unsigned long)t->tv_set.tv_usec,
- (unsigned long)t->tv_expires.tv_sec,
+ (unsigned long)t->tv_expires.tv_jiff,
(unsigned long)t->tv_expires.tv_usec,
t->delay_us,
t->data
"d: %6li us data: 0x%08lX"
"\n",
t->name,
- (unsigned long)t->tv_set.tv_sec,
+ (unsigned long)t->tv_set.tv_jiff,
(unsigned long)t->tv_set.tv_usec,
- (unsigned long)t->tv_expires.tv_sec,
+ (unsigned long)t->tv_expires.tv_jiff,
(unsigned long)t->tv_expires.tv_usec,
t->delay_us,
t->data
"d: %6li us data: 0x%08lX"
"\n",
t->name,
- (unsigned long)t->tv_set.tv_sec,
+ (unsigned long)t->tv_set.tv_jiff,
(unsigned long)t->tv_set.tv_usec,
- (unsigned long)t->tv_expires.tv_sec,
+ (unsigned long)t->tv_expires.tv_jiff,
(unsigned long)t->tv_expires.tv_usec,
t->delay_us,
t->data
/* " func: 0x%08lX" */
"\n",
t->name,
- (unsigned long)t->tv_set.tv_sec,
+ (unsigned long)t->tv_set.tv_jiff,
(unsigned long)t->tv_set.tv_usec,
- (unsigned long)t->tv_expires.tv_sec,
+ (unsigned long)t->tv_expires.tv_jiff,
(unsigned long)t->tv_expires.tv_usec,
t->delay_us,
t->data
/* , t->function */
);
- local_irq_disable();
+ local_irq_save(flags);
if (t->next != nextt)
{
printk(KERN_WARNING "timer removed!\n");
static struct fast_timer tr[10];
static int exp_num[10];
-static struct timeval tv_exp[100];
+static struct fasttime_t tv_exp[100];
static void test_timeout(unsigned long data)
{
int prev_num;
int j;
- struct timeval tv, tv0, tv1, tv2;
+ struct fasttime_t tv, tv0, tv1, tv2;
printk("fast_timer_test() start\n");
do_gettimeofday_fast(&tv);
{
do_gettimeofday_fast(&tv_exp[j]);
}
- printk("fast_timer_test() %is %06i\n", tv.tv_sec, tv.tv_usec);
+ printk(KERN_DEBUG "fast_timer_test() %is %06i\n",
+ tv.tv_jiff, tv.tv_usec);
for (j = 0; j < 1000; j++)
{
}
for (j = 0; j < 100; j++)
{
- printk("%i.%i %i.%i %i.%i %i.%i %i.%i\n",
- tv_exp[j].tv_sec,tv_exp[j].tv_usec,
- tv_exp[j+1].tv_sec,tv_exp[j+1].tv_usec,
- tv_exp[j+2].tv_sec,tv_exp[j+2].tv_usec,
- tv_exp[j+3].tv_sec,tv_exp[j+3].tv_usec,
- tv_exp[j+4].tv_sec,tv_exp[j+4].tv_usec);
+ printk(KERN_DEBUG "%i.%i %i.%i %i.%i %i.%i %i.%i\n",
+ tv_exp[j].tv_jiff, tv_exp[j].tv_usec,
+ tv_exp[j+1].tv_jiff, tv_exp[j+1].tv_usec,
+ tv_exp[j+2].tv_jiff, tv_exp[j+2].tv_usec,
+ tv_exp[j+3].tv_jiff, tv_exp[j+3].tv_usec,
+ tv_exp[j+4].tv_jiff, tv_exp[j+4].tv_usec);
j += 4;
}
do_gettimeofday_fast(&tv0);
}
}
do_gettimeofday_fast(&tv2);
- printk("Timers started %is %06i\n", tv0.tv_sec, tv0.tv_usec);
- printk("Timers started at %is %06i\n", tv1.tv_sec, tv1.tv_usec);
- printk("Timers done %is %06i\n", tv2.tv_sec, tv2.tv_usec);
+ printk(KERN_DEBUG "Timers started %is %06i\n",
+ tv0.tv_jiff, tv0.tv_usec);
+ printk(KERN_DEBUG "Timers started at %is %06i\n",
+ tv1.tv_jiff, tv1.tv_usec);
+ printk(KERN_DEBUG "Timers done %is %06i\n",
+ tv2.tv_jiff, tv2.tv_usec);
DP(printk("buf0:\n");
printk(buf0);
printk("buf1:\n");
printk("%-10s set: %6is %06ius exp: %6is %06ius "
"data: 0x%08X func: 0x%08X\n",
t->name,
- t->tv_set.tv_sec,
+ t->tv_set.tv_jiff,
t->tv_set.tv_usec,
- t->tv_expires.tv_sec,
+ t->tv_expires.tv_jiff,
t->tv_expires.tv_usec,
t->data,
t->function
printk(" del: %6ius did exp: %6is %06ius as #%i error: %6li\n",
t->delay_us,
- tv_exp[j].tv_sec,
+ tv_exp[j].tv_jiff,
tv_exp[j].tv_usec,
exp_num[j],
- (tv_exp[j].tv_sec - t->tv_expires.tv_sec)*1000000 + tv_exp[j].tv_usec - t->tv_expires.tv_usec);
+ (tv_exp[j].tv_jiff - t->tv_expires.tv_jiff) *
+ 1000000 + tv_exp[j].tv_usec -
+ t->tv_expires.tv_usec);
}
proc_fasttimer_read(buf5, NULL, 0, 0, 0);
printk("buf5 after all done:\n");
#endif
-void fast_timer_init(void)
+int fast_timer_init(void)
{
/* For some reason, request_irq() hangs when called froom time_init() */
if (!fast_timer_is_init)
fast_timer_test();
#endif
}
+ return 0;
}
+__initcall(fast_timer_init);
projects / linux-2.6 / commitdiff