diff options
Diffstat (limited to 'arch/cris')
| -rw-r--r-- | arch/cris/arch-v10/kernel/fasttimer.c | 315 |
1 files changed, 114 insertions, 201 deletions
diff --git a/arch/cris/arch-v10/kernel/fasttimer.c b/arch/cris/arch-v10/kernel/fasttimer.c index d3ea052e5ee..645d7059b40 100644 --- a/arch/cris/arch-v10/kernel/fasttimer.c +++ b/arch/cris/arch-v10/kernel/fasttimer.c @@ -1,97 +1,9 @@ -/* $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> @@ -125,7 +37,7 @@ #ifdef FAST_TIMER_SANITY_CHECKS #define SANITYCHECK(x) x -static int sanity_failed = 0; +static int sanity_failed; #else #define SANITYCHECK(x) #endif @@ -136,13 +48,13 @@ static int sanity_failed = 0; #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; @@ -150,8 +62,8 @@ 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) \ { \ @@ -206,42 +118,26 @@ int timer_freq_settings[NUM_TIMER_STATS]; 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) @@ -285,7 +181,7 @@ 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); @@ -340,7 +236,7 @@ void start_one_shot_timer(struct fast_timer *t, printk(KERN_WARNING "timer name: %s data: 0x%08lX already in list!\n", name, data); sanity_failed++; - return; + goto done; } else { @@ -356,11 +252,11 @@ void start_one_shot_timer(struct fast_timer *t, 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; @@ -401,6 +297,7 @@ void start_one_shot_timer(struct fast_timer *t, D2(printk("start_one_shot_timer: %d us done\n", delay_us)); +done: local_irq_restore(flags); } /* start_one_shot_timer */ @@ -444,11 +341,18 @@ int del_fast_timer(struct fast_timer * t) /* 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 */ @@ -466,16 +370,17 @@ timer1_handler(int irq, void *dev_id, struct pt_regs *regs) 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) { @@ -486,7 +391,6 @@ timer1_handler(int irq, void *dev_id, struct pt_regs *regs) 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; @@ -501,16 +405,23 @@ timer1_handler(int irq, void *dev_id, struct pt_regs *regs) } 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 { @@ -518,16 +429,20 @@ timer1_handler(int irq, void *dev_id, struct pt_regs *regs) 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) @@ -537,7 +452,6 @@ timer1_handler(int irq, void *dev_id, struct pt_regs *regs) #endif start_timer1(us); } - local_irq_restore(flags); break; } else @@ -548,9 +462,10 @@ timer1_handler(int irq, void *dev_id, struct pt_regs *regs) D1(printk("e! %d\n", us)); } } - local_irq_restore(flags); } + local_irq_restore(flags); + if (!t) { D1(printk("t1 stop!\n")); @@ -575,28 +490,17 @@ static void wake_up_func(unsigned long data) 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 @@ -616,7 +520,7 @@ static int proc_fasttimer_read(char *buf, char **start, off_t offset, int len 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; @@ -624,7 +528,8 @@ static int proc_fasttimer_read(char *buf, char **start, off_t offset, int len if (!bigbuf && !(bigbuf = vmalloc(BIG_BUF_SIZE))) { used = 0; - bigbuf[0] = '\0'; + if (buf) + buf[0] = '\0'; return 0; } @@ -646,7 +551,7 @@ static int proc_fasttimer_read(char *buf, char **start, off_t offset, int len 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", @@ -696,9 +601,9 @@ static int proc_fasttimer_read(char *buf, char **start, off_t offset, int len "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 @@ -718,9 +623,9 @@ static int proc_fasttimer_read(char *buf, char **start, off_t offset, int len "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 @@ -738,9 +643,9 @@ static int proc_fasttimer_read(char *buf, char **start, off_t offset, int len "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 @@ -761,15 +666,15 @@ static int proc_fasttimer_read(char *buf, char **start, off_t offset, int len /* " 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"); @@ -798,7 +703,7 @@ static volatile int num_test_timeout = 0; 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) { @@ -836,7 +741,7 @@ static void fast_timer_test(void) 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); @@ -849,7 +754,8 @@ static void fast_timer_test(void) { 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++) { @@ -858,12 +764,12 @@ static void fast_timer_test(void) } 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); @@ -895,9 +801,12 @@ static void fast_timer_test(void) } } 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"); @@ -919,9 +828,9 @@ static void fast_timer_test(void) 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 @@ -929,10 +838,12 @@ static void fast_timer_test(void) 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"); @@ -942,7 +853,7 @@ static void fast_timer_test(void) #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) @@ -975,4 +886,6 @@ void fast_timer_init(void) fast_timer_test(); #endif } + return 0; } +__initcall(fast_timer_init); |