The number of master->num_streams per master device is typically very
small in practice. Sorting this array takes a very small amount of
time, so there is no practical risk of triggering a soft lockup that
would necessitate calling cond_resched() during the sort.
Replace sort_nonatomic() with the standard sort(). Since this is the
only remaining in-tree caller of sort_nonatomic(), this change paves
the way to eventually remove the unused sort_nonatomic() API from the
core library.
Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
---
Build-tested only.
I'm not really familiar with this driver or smmu internals.
Based on my limited knowledge, master->num_streams should be small
enough to safely switch from sort_nonatomic() to sort(), but I could be
wrong.
Please review carefully and let me know if there are any cases where
num_streams could actually be large enough to cause issues.
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index a10affb483a4..dcb6be2df95e 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -4047,9 +4047,9 @@ static int arm_smmu_insert_master(struct arm_smmu_device *smmu,
}
/* Put the ids into order for sorted to_merge/to_unref arrays */
- sort_nonatomic(master->streams, master->num_streams,
- sizeof(master->streams[0]), arm_smmu_stream_id_cmp,
- NULL);
+ sort(master->streams, master->num_streams,
+ sizeof(master->streams[0]), arm_smmu_stream_id_cmp,
+ NULL);
mutex_lock(&smmu->streams_mutex);
for (i = 0; i < fwspec->num_ids; i++) {--
2.55.0.508.g3f0d502094-goog