[PATCH 1/2] habanalabs: remove dead code from free_device_memory()

From: Oded Gabbay
Date: Sun Jun 26 2022 - 06:33:20 EST


From: Tomer Tayar <ttayar@xxxxxxxxx>

free_device_memory() ends with if and else, each has a return statement,
followed by another return statement that can never be reached.
Restructure the function and remove this dead code.

Signed-off-by: Tomer Tayar <ttayar@xxxxxxxxx>
Reviewed-by: Oded Gabbay <ogabbay@xxxxxxxxxx>
Signed-off-by: Oded Gabbay <ogabbay@xxxxxxxxxx>
---
drivers/misc/habanalabs/common/memory.c | 50 +++++++++++--------------
1 file changed, 22 insertions(+), 28 deletions(-)

diff --git a/drivers/misc/habanalabs/common/memory.c b/drivers/misc/habanalabs/common/memory.c
index 4f35a5668fcb..bc921f32716a 100644
--- a/drivers/misc/habanalabs/common/memory.c
+++ b/drivers/misc/habanalabs/common/memory.c
@@ -359,41 +359,35 @@ static int free_device_memory(struct hl_ctx *ctx, struct hl_mem_in *args)

spin_lock(&vm->idr_lock);
phys_pg_pack = idr_find(&vm->phys_pg_pack_handles, handle);
- if (phys_pg_pack) {
- if (atomic_read(&phys_pg_pack->mapping_cnt) > 0) {
- dev_err(hdev->dev, "handle %u is mapped, cannot free\n",
- handle);
- spin_unlock(&vm->idr_lock);
- return -EINVAL;
- }
-
- if (phys_pg_pack->exporting_cnt) {
- dev_dbg(hdev->dev, "handle %u is exported, cannot free\n", handle);
- spin_unlock(&vm->idr_lock);
- return -EINVAL;
- }
-
- /*
- * must remove from idr before the freeing of the physical
- * pages as the refcount of the pool is also the trigger of the
- * idr destroy
- */
- idr_remove(&vm->phys_pg_pack_handles, handle);
+ if (!phys_pg_pack) {
spin_unlock(&vm->idr_lock);
+ dev_err(hdev->dev, "free device memory failed, no match for handle %u\n", handle);
+ return -EINVAL;
+ }

- atomic64_sub(phys_pg_pack->total_size, &ctx->dram_phys_mem);
- atomic64_sub(phys_pg_pack->total_size, &hdev->dram_used_mem);
+ if (atomic_read(&phys_pg_pack->mapping_cnt) > 0) {
+ spin_unlock(&vm->idr_lock);
+ dev_err(hdev->dev, "handle %u is mapped, cannot free\n", handle);
+ return -EINVAL;
+ }

- free_phys_pg_pack(hdev, phys_pg_pack);
- return 0;
- } else {
+ if (phys_pg_pack->exporting_cnt) {
spin_unlock(&vm->idr_lock);
- dev_err(hdev->dev,
- "free device memory failed, no match for handle %u\n",
- handle);
+ dev_dbg(hdev->dev, "handle %u is exported, cannot free\n", handle);
return -EINVAL;
}

+ /* must remove from idr before the freeing of the physical pages as the refcount of the pool
+ * is also the trigger of the idr destroy
+ */
+ idr_remove(&vm->phys_pg_pack_handles, handle);
+ spin_unlock(&vm->idr_lock);
+
+ atomic64_sub(phys_pg_pack->total_size, &ctx->dram_phys_mem);
+ atomic64_sub(phys_pg_pack->total_size, &hdev->dram_used_mem);
+
+ free_phys_pg_pack(hdev, phys_pg_pack);
+
return 0;
}

--
2.25.1