habanalabs: share a single ctx-mutex between all MMUs

Multiple locks are usually a source of problems, which in the MMU
case can be avoided since it is relatively rare that both MMU
tables are updated at the same time.

Therefore, use a single shared lock instead of two separate ones.

Signed-off-by: Moti Haimovski <mhaimovski@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>

diff --git a/drivers/misc/habanalabs/common/mmu.c b/drivers/misc/habanalabs/common/mmu.c
index 6f535c8..f4b3d02 100644 (file)
--- a/drivers/misc/habanalabs/common/mmu.c
+++ b/drivers/misc/habanalabs/common/mmu.c
@@ -81,6 +81,8 @@ int hl_mmu_ctx_init(struct hl_ctx *ctx)
        if (!hdev->mmu_enable)
                return 0;
 
+       mutex_init(&ctx->mmu_lock);
+
        if (hdev->mmu_func[MMU_DR_PGT].ctx_init != NULL) {
                rc = hdev->mmu_func[MMU_DR_PGT].ctx_init(ctx);
                if (rc)
@@ -115,6 +117,8 @@ void hl_mmu_ctx_fini(struct hl_ctx *ctx)
 
        if (hdev->mmu_func[MMU_HR_PGT].ctx_fini != NULL)
                hdev->mmu_func[MMU_HR_PGT].ctx_fini(ctx);
+
+       mutex_destroy(&ctx->mmu_lock);
 }
 
 /*

diff --git a/drivers/misc/habanalabs/common/mmu_v1.c b/drivers/misc/habanalabs/common/mmu_v1.c
index 5f62cb1..92b2229 100644 (file)
--- a/drivers/misc/habanalabs/common/mmu_v1.c
+++ b/drivers/misc/habanalabs/common/mmu_v1.c
@@ -481,9 +481,7 @@ static void hl_mmu_v1_fini(struct hl_device *hdev)
  */
 static int hl_mmu_v1_ctx_init(struct hl_ctx *ctx)
 {
-       mutex_init(&ctx->mmu_lock);
        hash_init(ctx->mmu_shadow_hash);
-
        return dram_default_mapping_init(ctx);
 }
 
@@ -516,8 +514,6 @@ static void hl_mmu_v1_ctx_fini(struct hl_ctx *ctx)
                        pgt_info->phys_addr, ctx->asid, pgt_info->num_of_ptes);
                _free_hop(ctx, pgt_info);
        }
-
-       mutex_destroy(&ctx->mmu_lock);
 }
 
 static int _hl_mmu_v1_unmap(struct hl_ctx *ctx,