From: Mikulas Patocka <mpatocka@xxxxxxxxxx>
commit bfe2b0146c4d0230b68f5c71a64380ff8d361f8b upstream.
dm-stats can be used with a very large number of entries (it is only
limited by 1/4 of total system memory), so add rescheduling points to
the loops that iterate over the entries.
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/md/dm-stats.c | 8 ++++++++
1 file changed, 8 insertions(+)
--- a/drivers/md/dm-stats.c
+++ b/drivers/md/dm-stats.c
@@ -228,6 +228,7 @@ void dm_stats_cleanup(struct dm_stats *s
atomic_read(&shared->in_flight[READ]),
atomic_read(&shared->in_flight[WRITE]));
}
+ cond_resched();
}
dm_stat_free(&s->rcu_head);
}
@@ -316,6 +317,7 @@ static int dm_stats_create(struct dm_sta
for (ni = 0; ni < n_entries; ni++) {
atomic_set(&s->stat_shared[ni].in_flight[READ], 0);
atomic_set(&s->stat_shared[ni].in_flight[WRITE], 0);
+ cond_resched();
}
if (s->n_histogram_entries) {
@@ -328,6 +330,7 @@ static int dm_stats_create(struct dm_sta
for (ni = 0; ni < n_entries; ni++) {
s->stat_shared[ni].tmp.histogram = hi;
hi += s->n_histogram_entries + 1;
+ cond_resched();
}
}
@@ -348,6 +351,7 @@ static int dm_stats_create(struct dm_sta
for (ni = 0; ni < n_entries; ni++) {
p[ni].histogram = hi;
hi += s->n_histogram_entries + 1;
+ cond_resched();
}
}
}
@@ -477,6 +481,7 @@ static int dm_stats_list(struct dm_stats
}
DMEMIT("\n");
}
+ cond_resched();
}
mutex_unlock(&stats->mutex);
@@ -753,6 +758,7 @@ static void __dm_stat_clear(struct dm_st
local_irq_enable();
}
}
+ cond_resched();
}
}
@@ -868,6 +874,8 @@ static int dm_stats_print(struct dm_stat
if (unlikely(sz + 1 >= maxlen))
goto buffer_overflow;
+
+ cond_resched();
}
if (clear)
