From ecdcc0234b27472b561378ac59e2beeea06ec6ff Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Fri, 27 Apr 2007 16:01:58 +0200 Subject: [PATCH] [S390] Switch etr from tasklet to workqueue. The clock synchronization of the ETR code requires an smp_call_function to synchronize all cpus. Calling smp_call_function from a tasklet is illegal. Replace the tasklet with a job on the global workqueue. ETR work is rare and can be postponed to a be done by a kernel thread. Signed-off-by: Martin Schwidefsky --- arch/s390/kernel/time.c | 34 +++++++++++++++++----------------- 1 file changed, 17 insertions(+), 17 deletions(-) diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c index e1ad464b6f20..711dae8da7ad 100644 --- a/arch/s390/kernel/time.c +++ b/arch/s390/kernel/time.c @@ -280,7 +280,6 @@ static void clock_comparator_interrupt(__u16 code) } static void etr_reset(void); -static void etr_init(void); static void etr_ext_handler(__u16); /* @@ -355,7 +354,6 @@ void __init time_init(void) #ifdef CONFIG_VIRT_TIMER vtime_init(); #endif - etr_init(); } /* @@ -426,11 +424,11 @@ static struct etr_aib etr_port1; static int etr_port1_uptodate; static unsigned long etr_events; static struct timer_list etr_timer; -static struct tasklet_struct etr_tasklet; static DEFINE_PER_CPU(atomic_t, etr_sync_word); static void etr_timeout(unsigned long dummy); -static void etr_tasklet_fn(unsigned long dummy); +static void etr_work_fn(struct work_struct *work); +static DECLARE_WORK(etr_work, etr_work_fn); /* * The etr get_clock function. It will write the current clock value @@ -507,29 +505,31 @@ static void etr_reset(void) } } -static void etr_init(void) +static int __init etr_init(void) { struct etr_aib aib; if (test_bit(ETR_FLAG_ENOSYS, &etr_flags)) - return; + return 0; /* Check if this machine has the steai instruction. */ if (etr_steai(&aib, ETR_STEAI_STEPPING_PORT) == 0) set_bit(ETR_FLAG_STEAI, &etr_flags); setup_timer(&etr_timer, etr_timeout, 0UL); - tasklet_init(&etr_tasklet, etr_tasklet_fn, 0); if (!etr_port0_online && !etr_port1_online) set_bit(ETR_FLAG_EACCES, &etr_flags); if (etr_port0_online) { set_bit(ETR_EVENT_PORT0_CHANGE, &etr_events); - tasklet_hi_schedule(&etr_tasklet); + schedule_work(&etr_work); } if (etr_port1_online) { set_bit(ETR_EVENT_PORT1_CHANGE, &etr_events); - tasklet_hi_schedule(&etr_tasklet); + schedule_work(&etr_work); } + return 0; } +arch_initcall(etr_init); + /* * Two sorts of ETR machine checks. The architecture reads: * "When a machine-check niterruption occurs and if a switch-to-local or @@ -549,7 +549,7 @@ void etr_switch_to_local(void) return; etr_disable_sync_clock(NULL); set_bit(ETR_EVENT_SWITCH_LOCAL, &etr_events); - tasklet_hi_schedule(&etr_tasklet); + schedule_work(&etr_work); } /* @@ -564,7 +564,7 @@ void etr_sync_check(void) return; etr_disable_sync_clock(NULL); set_bit(ETR_EVENT_SYNC_CHECK, &etr_events); - tasklet_hi_schedule(&etr_tasklet); + schedule_work(&etr_work); } /* @@ -591,13 +591,13 @@ static void etr_ext_handler(__u16 code) * Both ports are not up-to-date now. */ set_bit(ETR_EVENT_PORT_ALERT, &etr_events); - tasklet_hi_schedule(&etr_tasklet); + schedule_work(&etr_work); } static void etr_timeout(unsigned long dummy) { set_bit(ETR_EVENT_UPDATE, &etr_events); - tasklet_hi_schedule(&etr_tasklet); + schedule_work(&etr_work); } /* @@ -927,7 +927,7 @@ static struct etr_eacr etr_handle_update(struct etr_aib *aib, if (!eacr.e0 && !eacr.e1) return eacr; - /* Update port0 or port1 with aib stored in etr_tasklet_fn. */ + /* Update port0 or port1 with aib stored in etr_work_fn. */ if (aib->esw.q == 0) { /* Information for port 0 stored. */ if (eacr.p0 && !etr_port0_uptodate) { @@ -1007,7 +1007,7 @@ static void etr_update_eacr(struct etr_eacr eacr) * particular this is the only function that calls etr_update_eacr(), * it "controls" the etr control register. */ -static void etr_tasklet_fn(unsigned long dummy) +static void etr_work_fn(struct work_struct *work) { unsigned long long now; struct etr_eacr eacr; @@ -1220,13 +1220,13 @@ static ssize_t etr_online_store(struct sys_device *dev, return count; /* Nothing to do. */ etr_port0_online = value; set_bit(ETR_EVENT_PORT0_CHANGE, &etr_events); - tasklet_hi_schedule(&etr_tasklet); + schedule_work(&etr_work); } else { if (etr_port1_online == value) return count; /* Nothing to do. */ etr_port1_online = value; set_bit(ETR_EVENT_PORT1_CHANGE, &etr_events); - tasklet_hi_schedule(&etr_tasklet); + schedule_work(&etr_work); } return count; } -- 2.39.2