[MIPS] Protect more of timer_interrupt() by xtime_lock.

From Dave Johnson <djohnson+linuxmips@sw.starentnetworks.com>:

* do_timer() expects the arch-specific handler to take the lock as it
  modifies jiffies[_64] and xtime.
* writing timerhi/lo in timer_interrupt() will mess up
  fixed_rate_gettimeoffset() which reads timerhi/lo.
    
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This commit is contained in:
Ralf Baechle 2006-03-14 23:46:58 +00:00
parent 966f4406d9
commit d6bd0e6b32

View File

@ -424,6 +424,8 @@ irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
unsigned long j;
unsigned int count;
write_seqlock(&xtime_lock);
count = mips_hpt_read();
mips_timer_ack();
@ -441,7 +443,6 @@ irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
* CMOS clock accordingly every ~11 minutes. rtc_set_time() has to be
* called as close as possible to 500 ms before the new second starts.
*/
write_seqlock(&xtime_lock);
if (ntp_synced() &&
xtime.tv_sec > last_rtc_update + 660 &&
(xtime.tv_nsec / 1000) >= 500000 - ((unsigned) TICK_SIZE) / 2 &&
@ -453,7 +454,6 @@ irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
last_rtc_update = xtime.tv_sec - 600;
}
}
write_sequnlock(&xtime_lock);
/*
* If jiffies has overflown in this timer_interrupt, we must
@ -496,6 +496,8 @@ irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
}
}
write_sequnlock(&xtime_lock);
/*
* In UP mode, we call local_timer_interrupt() to do profiling
* and process accouting.