dm-stats can be used with very large number of entries (it is only limited by 1/4 of total system memory), so we should add rescheduling points to the loops that iterate over the entries.
Signed-off-by: Mikulas Patocka <[email protected]> Cc: [email protected] --- drivers/md/dm-stats.c | 8 ++++++++ 1 file changed, 8 insertions(+) Index: linux-2.6/drivers/md/dm-stats.c =================================================================== --- linux-2.6.orig/drivers/md/dm-stats.c 2022-04-24 18:51:25.000000000 +0200 +++ linux-2.6/drivers/md/dm-stats.c 2022-04-24 18:51:25.000000000 +0200 @@ -225,6 +225,7 @@ 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); } @@ -330,6 +331,7 @@ 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) { @@ -342,6 +344,7 @@ 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(); } } @@ -362,6 +365,7 @@ 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(); } } } @@ -497,6 +501,7 @@ static int dm_stats_list(struct dm_stats } DMEMIT("\n"); } + cond_resched(); } mutex_unlock(&stats->mutex); @@ -774,6 +779,7 @@ static void __dm_stat_clear(struct dm_st local_irq_enable(); } } + cond_resched(); } } @@ -889,6 +895,8 @@ static int dm_stats_print(struct dm_stat if (unlikely(sz + 1 >= maxlen)) goto buffer_overflow; + + cond_resched(); } if (clear) -- dm-devel mailing list [email protected] https://listman.redhat.com/mailman/listinfo/dm-devel
