sh: fix xtime_lock deadlocking.
move update_process_times() out from under xtime_lock.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/kernel/time_64.c b/arch/sh/kernel/time_64.c
index f819ba3..898977e 100644
--- a/arch/sh/kernel/time_64.c
+++ b/arch/sh/kernel/time_64.c
@@ -229,15 +229,22 @@
static inline void do_timer_interrupt(void)
{
unsigned long long current_ctc;
+
+ if (current->pid)
+ profile_tick(CPU_PROFILING);
+
+ /*
+ * Here we are in the timer irq handler. We just have irqs locally
+ * disabled but we don't know if the timer_bh is running on the other
+ * CPU. We need to avoid to SMP race with it. NOTE: we don' t need
+ * the irq version of write_lock because as just said we have irq
+ * locally disabled. -arca
+ */
+ write_lock(&xtime_lock);
asm ("getcon cr62, %0" : "=r" (current_ctc));
ctc_last_interrupt = (unsigned long) current_ctc;
do_timer(1);
-#ifndef CONFIG_SMP
- update_process_times(user_mode(get_irq_regs()));
-#endif
- if (current->pid)
- profile_tick(CPU_PROFILING);
#ifdef CONFIG_HEARTBEAT
if (sh_mv.mv_heartbeat != NULL)
@@ -259,6 +266,11 @@
/* do it again in 60 s */
last_rtc_update = xtime.tv_sec - 600;
}
+ write_unlock(&xtime_lock);
+
+#ifndef CONFIG_SMP
+ update_process_times(user_mode(get_irq_regs()));
+#endif
}
/*
@@ -275,16 +287,7 @@
timer_status &= ~0x100;
ctrl_outw(timer_status, TMU0_TCR);
- /*
- * Here we are in the timer irq handler. We just have irqs locally
- * disabled but we don't know if the timer_bh is running on the other
- * CPU. We need to avoid to SMP race with it. NOTE: we don' t need
- * the irq version of write_lock because as just said we have irq
- * locally disabled. -arca
- */
- write_lock(&xtime_lock);
do_timer_interrupt();
- write_unlock(&xtime_lock);
return IRQ_HANDLED;
}