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Diffstat (limited to 'drivers/s390/cio/css.c')
-rw-r--r--drivers/s390/cio/css.c26
1 files changed, 19 insertions, 7 deletions
diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c
index 8c2cb87..0268e5f 100644
--- a/drivers/s390/cio/css.c
+++ b/drivers/s390/cio/css.c
@@ -69,7 +69,8 @@ static int call_fn_known_sch(struct device *dev, void *data)
struct cb_data *cb = data;
int rc = 0;
- idset_sch_del(cb->set, sch->schid);
+ if (cb->set)
+ idset_sch_del(cb->set, sch->schid);
if (cb->fn_known_sch)
rc = cb->fn_known_sch(sch, cb->data);
return rc;
@@ -115,6 +116,13 @@ int for_each_subchannel_staged(int (*fn_known)(struct subchannel *, void *),
cb.fn_known_sch = fn_known;
cb.fn_unknown_sch = fn_unknown;
+ if (fn_known && !fn_unknown) {
+ /* Skip idset allocation in case of known-only loop. */
+ cb.set = NULL;
+ return bus_for_each_dev(&css_bus_type, NULL, &cb,
+ call_fn_known_sch);
+ }
+
cb.set = idset_sch_new();
if (!cb.set)
/* fall back to brute force scanning in case of oom */
@@ -553,6 +561,9 @@ static int slow_eval_unknown_fn(struct subchannel_id schid, void *data)
default:
rc = 0;
}
+ /* Allow scheduling here since the containing loop might
+ * take a while. */
+ cond_resched();
}
return rc;
}
@@ -572,7 +583,7 @@ static void css_slow_path_func(struct work_struct *unused)
spin_unlock_irqrestore(&slow_subchannel_lock, flags);
}
-static DECLARE_WORK(slow_path_work, css_slow_path_func);
+static DECLARE_DELAYED_WORK(slow_path_work, css_slow_path_func);
struct workqueue_struct *cio_work_q;
void css_schedule_eval(struct subchannel_id schid)
@@ -582,7 +593,7 @@ void css_schedule_eval(struct subchannel_id schid)
spin_lock_irqsave(&slow_subchannel_lock, flags);
idset_sch_add(slow_subchannel_set, schid);
atomic_set(&css_eval_scheduled, 1);
- queue_work(cio_work_q, &slow_path_work);
+ queue_delayed_work(cio_work_q, &slow_path_work, 0);
spin_unlock_irqrestore(&slow_subchannel_lock, flags);
}
@@ -593,7 +604,7 @@ void css_schedule_eval_all(void)
spin_lock_irqsave(&slow_subchannel_lock, flags);
idset_fill(slow_subchannel_set);
atomic_set(&css_eval_scheduled, 1);
- queue_work(cio_work_q, &slow_path_work);
+ queue_delayed_work(cio_work_q, &slow_path_work, 0);
spin_unlock_irqrestore(&slow_subchannel_lock, flags);
}
@@ -606,7 +617,7 @@ static int __unset_registered(struct device *dev, void *data)
return 0;
}
-static void css_schedule_eval_all_unreg(void)
+void css_schedule_eval_all_unreg(unsigned long delay)
{
unsigned long flags;
struct idset *unreg_set;
@@ -624,7 +635,7 @@ static void css_schedule_eval_all_unreg(void)
spin_lock_irqsave(&slow_subchannel_lock, flags);
idset_add_set(slow_subchannel_set, unreg_set);
atomic_set(&css_eval_scheduled, 1);
- queue_work(cio_work_q, &slow_path_work);
+ queue_delayed_work(cio_work_q, &slow_path_work, delay);
spin_unlock_irqrestore(&slow_subchannel_lock, flags);
idset_free(unreg_set);
}
@@ -637,7 +648,8 @@ void css_wait_for_slow_path(void)
/* Schedule reprobing of all unregistered subchannels. */
void css_schedule_reprobe(void)
{
- css_schedule_eval_all_unreg();
+ /* Schedule with a delay to allow merging of subsequent calls. */
+ css_schedule_eval_all_unreg(1 * HZ);
}
EXPORT_SYMBOL_GPL(css_schedule_reprobe);
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