diff options
Diffstat (limited to 'drivers/dahdi/dahdi_dummy.c')
| -rw-r--r-- | drivers/dahdi/dahdi_dummy.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/drivers/dahdi/dahdi_dummy.c b/drivers/dahdi/dahdi_dummy.c index 97949e3..590cc9b 100644 --- a/drivers/dahdi/dahdi_dummy.c +++ b/drivers/dahdi/dahdi_dummy.c @@ -161,12 +161,31 @@ static void dahdi_dummy_timer(unsigned long param) unsigned long ms_since_start; struct timespec now; const unsigned long MAX_INTERVAL = 100000L; + const unsigned long MS_LIMIT = 3000; if (!atomic_read(&shutdown)) mod_timer(&timer, jiffies + JIFFIES_INTERVAL); now = current_kernel_time(); ms_since_start = timespec_diff_ms(&ztd->start_interval, &now); + + /* + * If the system time has changed, it is possible for us to be far + * behind. If we are more than MS_LIMIT milliseconds behind, just + * reset our time base and continue so that we do not hang the system + * here. + * + */ + if (unlikely((ms_since_start - ztd->calls_since_start) > MS_LIMIT)) { + if (printk_ratelimit()) { + printk(KERN_INFO + "dahdi_dummy: Detected time shift.\n"); + } + ztd->calls_since_start = 0; + ztd->start_interval = now; + return; + } + while (ms_since_start > ztd->calls_since_start) { ztd->calls_since_start++; dahdi_receive(&ztd->span); |