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MTK 平台：wd_common_drv.c
static int kwdt_thread(void *arg)
{
struct sched_param param = {.sched_priority = 99 };
struct rtc_time tm;
struct timeval tv = { 0 };
/* android time */
struct rtc_time tm_android;
struct timeval tv_android = { 0 };
int cpu = 0;
int local_bit = 0, loc_need_config = 0, loc_timeout = 0;
struct wd_api *loc_wk_wdt = NULL;
sched_setscheduler(current, SCHED_FIFO, ¶m);
set_current_state(TASK_INTERRUPTIBLE);
for (;;) {
if (kthread_should_stop()) {
pr_err("[WDK] kthread_should_stop do !!\n");
break;
}
spin_lock(&lock);
cpu = smp_processor_id();
loc_wk_wdt = g_wd_api;
loc_need_config = g_need_config;
loc_timeout = g_timeout;
spin_unlock(&lock);
/* printk("fwq loc_wk_wdt(%x),loc_wk_wdt->ready(%d)\n",loc_wk_wdt ,loc_wk_wdt->ready); */
if (loc_wk_wdt && loc_wk_wdt->ready && g_enable) {
if (loc_need_config) {
/* daul mode */
loc_wk_wdt->wd_config(WDT_DUAL_MODE, loc_timeout);
spin_lock(&lock);
g_need_config = 0;
spin_unlock(&lock);
}
/* pr_debug("[WDK] cpu-task=%d, current_pid=%d\n", wk_tsk[cpu]->pid, current->pid); */
/*to avoid wk_tsk[cpu] had not created out */
if (wk_tsk[cpu] != 0) {
if (wk_tsk[cpu]->pid == current->pid) {
/* only process WDT info if thread-x is on cpu-x */
spin_lock(&lock);
local_bit = kick_bit;
printk_deferred("[WDK], local_bit:0x%x, cpu:%d,RT[%lld]\n",
local_bit, cpu, sched_clock());
if ((local_bit & (1 << cpu)) == 0) {
/* printk("[WDK]: set WDT kick_bit\n"); */
local_bit |= (1 << cpu);
/* aee_rr_rec_wdk_kick_jiffies(jiffies); */
}
printk_deferred
("[WDK], local_bit:0x%x, cpu:%d, check bit0x:%x, lasthpg_cpu:%d, lasthpg_act:%d, lasthpg_t:%lld, RT[%lld]\n",
local_bit, cpu, wk_check_kick_bit(), lasthpg_cpu, lasthpg_act, lasthpg_t, sched_clock());
if (local_bit == wk_check_kick_bit()) {
printk_deferred("[WDK]: kick Ex WDT,RT[%lld]\n",
sched_clock());
mtk_wdt_restart(WD_TYPE_NORMAL); /* for KICK external wdt */
local_bit = 0;
}
kick_bit = local_bit;
spin_unlock(&lock); if (local_bit == wk_check_kick_bit()) {
printk_deferred("[WDK]: kick Ex WDT,RT[%lld]\n",
sched_clock());
mtk_wdt_restart(WD_TYPE_NORMAL); /* for KICK external wdt */
local_bit = 0;
}
}
}
} else if (0 == g_enable) {
pr_debug("WDK stop to kick\n");
} else {
pr_err("No watch dog driver is hooked\n");
BUG();
}
/*to avoid wk_tsk[cpu] had not created out */
if (wk_tsk[cpu] != 0) {
if (wk_tsk[cpu]->pid == current->pid) {
#if (DEBUG_WDK == 1)
msleep_interruptible(debug_sleep * 1000);
pr_debug("WD kicker woke up %d\n", debug_sleep);
#endif
do_gettimeofday(&tv);
tv_android = tv;
rtc_time_to_tm(tv.tv_sec, &tm);
tv_android.tv_sec -= sys_tz.tz_minuteswest * 60;
rtc_time_to_tm(tv_android.tv_sec, &tm_android);
printk_deferred
("[thread:%d][RT:%lld] %d-%02d-%02d %02d:%02d:%02d.%u UTC;"
"android time %d-%02d-%02d %02d:%02d:%02d.%03d\n",
current->pid, sched_clock(), tm.tm_year + 1900, tm.tm_mon + 1,
tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec,
(unsigned int)tv.tv_usec, tm_android.tm_year + 1900,
tm_android.tm_mon + 1, tm_android.tm_mday, tm_android.tm_hour,
tm_android.tm_min, tm_android.tm_sec,
(unsigned int)tv_android.tv_usec);
}
}
msleep_interruptible((g_kinterval) * 1000);
#ifdef CONFIG_MTK_AEE_POWERKEY_HANG_DETECT
if ((cpu == 0) && (wk_tsk[cpu]->pid == current->pid)) { /* only effect at cpu0 */
if (aee_kernel_wdt_kick_api(g_kinterval) == WDT_PWK_HANG_FORCE_HWT) {
printk_deferred("power key trigger HWT\n");
cpus_kick_bit = 0xFFFF; /* Try to force to HWT */
}
}
#endif
}
pr_debug("[WDK] WDT kicker thread stop, cpu:%d, pid:%d\n", cpu, current->pid);
return 0;
}log信息：
03-22 19:32:48.433 <4>[ 1243.156500] (0)[184:wdtk-0][WDK], local_bit:0x1, cpu:0, check bit0x:f, lasthpg_cpu:3, lasthpg_act:1, lasthpg_t:1241783575417, RT[1243156495036]
03-22 19:40:14.882 <4>[ 1243.166510] (1)[186:wdtk-1][WDK], local_bit:0x3, cpu:1, check bit0x:f, lasthpg_cpu:3, lasthpg_act:1, lasthpg_t:1241783575417, RT[1243166504728]
03-22 19:40:14.891 <4>[ 1243.176509] (2)[187:wdtk-2][WDK], local_bit:0x7, cpu:2, check bit0x:f, lasthpg_cpu:3, lasthpg_act:1, lasthpg_t:1241783575417, RT[1243176503959]
03-22 19:40:14.921 <4>[ 1243.206501] (3)[188:wdtk-3][WDK], local_bit:0xf, cpu:3, check bit0x:f, lasthpg_cpu:3, lasthpg_act:1, lasthpg_t:1241783575417, RT[1243206495498]
03-22 19:40:34.881 <4>[ 1263.166505] (0)[184:wdtk-0][WDK], local_bit:0x1, cpu:0, check bit0x:f, lasthpg_cpu:3, lasthpg_act:1, lasthpg_t:1245090018348, RT[1263166500007]
03-22 19:40:34.891 <4>[ 1263.176500] (1)[186:wdtk-1][WDK], local_bit:0x3, cpu:1, check bit0x:f, lasthpg_cpu:3, lasthpg_act:1, lasthpg_t:1245090018348, RT[1263176491084]
03-22 19:40:34.902 <4>[ 1263.186523] (2)[187:wdtk-2][WDK], local_bit:0x7, cpu:2, check bit0x:f, lasthpg_cpu:3, lasthpg_act:1, lasthpg_t:1245090018348, RT[1263186517314]
03-22 19:40:34.931 <4>[ 1263.216497] (3)[188:wdtk-3][WDK], local_bit:0xf, cpu:3, check bit0x:f, lasthpg_cpu:3, lasthpg_act:1, lasthpg_t:1245090018348, RT[1263216491930]
从log 看每个CPU喂狗时间间隔（RT）大概在20s