From: Rob Herring Date: Mon, 26 Aug 2019 22:33:12 +0000 (-0500) Subject: drm/panfrost: Remove unnecessary mmu->lock mutex X-Git-Tag: v5.4-rc1~32^2~4^2~6 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=e316f08f1abf5f1116118e25dce7bc3e9ab03246;p=platform%2Fkernel%2Flinux-rpi.git drm/panfrost: Remove unnecessary mmu->lock mutex There's no need to serialize io-pgtable calls and the as_lock is sufficient to serialize flush operations, so we can remove the per page table lock. Fixes: 7282f7645d06 ("drm/panfrost: Implement per FD address spaces") Suggested-by: Robin Murphy Cc: Tomeu Vizoso Cc: David Airlie Cc: Daniel Vetter Signed-off-by: Rob Herring Acked-by: Alyssa Rosenzweig Reviewed-by: Robin Murphy Reviewed-by: Steven Price Link: https://patchwork.freedesktop.org/patch/msgid/20190826223317.28509-4-robh@kernel.org --- diff --git a/drivers/gpu/drm/panfrost/panfrost_device.h b/drivers/gpu/drm/panfrost/panfrost_device.h index f503c56..b7fa08e 100644 --- a/drivers/gpu/drm/panfrost/panfrost_device.h +++ b/drivers/gpu/drm/panfrost/panfrost_device.h @@ -104,7 +104,6 @@ struct panfrost_device { struct panfrost_mmu { struct io_pgtable_cfg pgtbl_cfg; struct io_pgtable_ops *pgtbl_ops; - struct mutex lock; int as; atomic_t as_count; struct list_head list; diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c index 842bdd7..3a8bcfa 100644 --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c @@ -228,8 +228,6 @@ static int mmu_map_sg(struct panfrost_device *pfdev, struct panfrost_mmu *mmu, struct io_pgtable_ops *ops = mmu->pgtbl_ops; u64 start_iova = iova; - mutex_lock(&mmu->lock); - for_each_sg(sgt->sgl, sgl, sgt->nents, count) { unsigned long paddr = sg_dma_address(sgl); size_t len = sg_dma_len(sgl); @@ -249,8 +247,6 @@ static int mmu_map_sg(struct panfrost_device *pfdev, struct panfrost_mmu *mmu, mmu_hw_do_operation(pfdev, mmu, start_iova, iova - start_iova, AS_COMMAND_FLUSH_PT); - mutex_unlock(&mmu->lock); - return 0; } @@ -304,8 +300,6 @@ void panfrost_mmu_unmap(struct panfrost_gem_object *bo) if (ret < 0) return; - mutex_lock(&bo->mmu->lock); - while (unmapped_len < len) { size_t unmapped_page; size_t pgsize = get_pgsize(iova, len - unmapped_len); @@ -321,8 +315,6 @@ void panfrost_mmu_unmap(struct panfrost_gem_object *bo) mmu_hw_do_operation(pfdev, bo->mmu, bo->node.start << PAGE_SHIFT, bo->node.size << PAGE_SHIFT, AS_COMMAND_FLUSH_PT); - mutex_unlock(&bo->mmu->lock); - pm_runtime_mark_last_busy(pfdev->dev); pm_runtime_put_autosuspend(pfdev->dev); bo->is_mapped = false; @@ -356,7 +348,6 @@ int panfrost_mmu_pgtable_alloc(struct panfrost_file_priv *priv) struct panfrost_mmu *mmu = &priv->mmu; struct panfrost_device *pfdev = priv->pfdev; - mutex_init(&mmu->lock); INIT_LIST_HEAD(&mmu->list); mmu->as = -1;