Replace the three nearly identical copies of the code with a single function. And take advantage of the opportunity to do some micro-optimisation: avoid the vmalloc if at all possible and also avoid dropping the lock unless we are forced to acquire the mm semaphore.
Signed-off-by: Chris Wilson <[email protected]> --- drivers/gpu/drm/i915/i915_gem.c | 132 ++++++++++++++++++++++----------------- 1 files changed, 75 insertions(+), 57 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 33830c9..0028f3b 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -257,6 +257,56 @@ static int i915_gem_object_needs_bit17_swizzle(struct drm_i915_gem_object *obj) obj->tiling_mode != I915_TILING_NONE; } +static int +i915_gem_get_user_pages(struct drm_device *dev, + unsigned long addr, + bool write, + int *num_pages, + struct page ***pages_out) +{ + struct page **pages; + int pinned, ret; + int n = *num_pages; + + pages = kmalloc(n*sizeof(struct page *), + GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN); + if (pages == NULL) { + pages = drm_malloc_ab(n, sizeof(struct page *)); + if (pages == NULL) { + *pages_out = NULL; + *num_pages = 0; + return -ENOMEM; + } + } + + pinned = __get_user_pages_fast(addr, n, write, pages); + if (pinned < n) { + struct mm_struct *mm = current->mm; + + mutex_unlock(&dev->struct_mutex); + down_read(&mm->mmap_sem); + ret = get_user_pages(current, mm, + addr + (pinned << PAGE_SHIFT), + n - pinned, + write, 0, + pages + pinned, + NULL); + up_read(&mm->mmap_sem); + mutex_lock(&dev->struct_mutex); + if (ret > 0) + pinned += ret; + } + + ret = 0; + if (pinned < n) + ret = -EFAULT; + + *num_pages = pinned; + *pages_out = pages; + return ret; +} + + static inline void slow_shmem_copy(struct page *dst_page, int dst_offset, @@ -398,11 +448,11 @@ i915_gem_shmem_pread_slow(struct drm_device *dev, struct drm_file *file) { struct address_space *mapping = obj->base.filp->f_path.dentry->d_inode->i_mapping; - struct mm_struct *mm = current->mm; struct page **user_pages; ssize_t remain; - loff_t offset, pinned_pages, i; - loff_t first_data_page, last_data_page, num_pages; + loff_t offset; + loff_t first_data_page, last_data_page; + int num_pages, i; int shmem_page_offset; int data_page_index, data_page_offset; int page_length; @@ -420,20 +470,10 @@ i915_gem_shmem_pread_slow(struct drm_device *dev, last_data_page = (data_ptr + args->size - 1) / PAGE_SIZE; num_pages = last_data_page - first_data_page + 1; - user_pages = drm_malloc_ab(num_pages, sizeof(struct page *)); - if (user_pages == NULL) - return -ENOMEM; - - mutex_unlock(&dev->struct_mutex); - down_read(&mm->mmap_sem); - pinned_pages = get_user_pages(current, mm, (uintptr_t)args->data_ptr, - num_pages, 1, 0, user_pages, NULL); - up_read(&mm->mmap_sem); - mutex_lock(&dev->struct_mutex); - if (pinned_pages < num_pages) { - ret = -EFAULT; + ret = i915_gem_get_user_pages(dev, data_ptr, true, + &num_pages, &user_pages); + if (ret) goto out; - } ret = i915_gem_object_set_cpu_read_domain_range(obj, args->offset, @@ -494,7 +534,7 @@ i915_gem_shmem_pread_slow(struct drm_device *dev, } out: - for (i = 0; i < pinned_pages; i++) { + for (i = 0; i < num_pages; i++) { SetPageDirty(user_pages[i]); mark_page_accessed(user_pages[i]); page_cache_release(user_pages[i]); @@ -679,10 +719,9 @@ i915_gem_gtt_pwrite_slow(struct drm_device *dev, drm_i915_private_t *dev_priv = dev->dev_private; ssize_t remain; loff_t gtt_page_base, offset; - loff_t first_data_page, last_data_page, num_pages; - loff_t pinned_pages, i; + loff_t first_data_page, last_data_page; + int num_pages, i; struct page **user_pages; - struct mm_struct *mm = current->mm; int gtt_page_offset, data_page_offset, data_page_index, page_length; int ret; uint64_t data_ptr = args->data_ptr; @@ -697,28 +736,18 @@ i915_gem_gtt_pwrite_slow(struct drm_device *dev, last_data_page = (data_ptr + args->size - 1) / PAGE_SIZE; num_pages = last_data_page - first_data_page + 1; - user_pages = drm_malloc_ab(num_pages, sizeof(struct page *)); - if (user_pages == NULL) - return -ENOMEM; - - mutex_unlock(&dev->struct_mutex); - down_read(&mm->mmap_sem); - pinned_pages = get_user_pages(current, mm, (uintptr_t)args->data_ptr, - num_pages, 0, 0, user_pages, NULL); - up_read(&mm->mmap_sem); - mutex_lock(&dev->struct_mutex); - if (pinned_pages < num_pages) { - ret = -EFAULT; - goto out_unpin_pages; - } + ret = i915_gem_get_user_pages(dev, data_ptr, false, + &num_pages, &user_pages); + if (ret) + goto out; ret = i915_gem_object_set_to_gtt_domain(obj, true); if (ret) - goto out_unpin_pages; + goto out; ret = i915_gem_object_put_fence(obj); if (ret) - goto out_unpin_pages; + goto out; offset = obj->gtt_offset + args->offset; @@ -753,8 +782,8 @@ i915_gem_gtt_pwrite_slow(struct drm_device *dev, data_ptr += page_length; } -out_unpin_pages: - for (i = 0; i < pinned_pages; i++) +out: + for (i = 0; i < num_pages; i++) page_cache_release(user_pages[i]); drm_free_large(user_pages); @@ -803,11 +832,11 @@ i915_gem_shmem_pwrite_fast(struct drm_device *dev, if (IS_ERR(page)) return PTR_ERR(page); - vaddr = kmap_atomic(page, KM_USER0); + vaddr = kmap_atomic(page); ret = __copy_from_user_inatomic(vaddr + page_offset, user_data, page_length); - kunmap_atomic(vaddr, KM_USER0); + kunmap_atomic(vaddr); set_page_dirty(page); mark_page_accessed(page); @@ -842,11 +871,10 @@ i915_gem_shmem_pwrite_slow(struct drm_device *dev, struct drm_file *file) { struct address_space *mapping = obj->base.filp->f_path.dentry->d_inode->i_mapping; - struct mm_struct *mm = current->mm; struct page **user_pages; ssize_t remain; - loff_t offset, pinned_pages, i; - loff_t first_data_page, last_data_page, num_pages; + loff_t first_data_page, last_data_page, offset; + int num_pages, i; int shmem_page_offset; int data_page_index, data_page_offset; int page_length; @@ -864,20 +892,10 @@ i915_gem_shmem_pwrite_slow(struct drm_device *dev, last_data_page = (data_ptr + args->size - 1) / PAGE_SIZE; num_pages = last_data_page - first_data_page + 1; - user_pages = drm_malloc_ab(num_pages, sizeof(struct page *)); - if (user_pages == NULL) - return -ENOMEM; - - mutex_unlock(&dev->struct_mutex); - down_read(&mm->mmap_sem); - pinned_pages = get_user_pages(current, mm, (uintptr_t)args->data_ptr, - num_pages, 0, 0, user_pages, NULL); - up_read(&mm->mmap_sem); - mutex_lock(&dev->struct_mutex); - if (pinned_pages < num_pages) { - ret = -EFAULT; + ret = i915_gem_get_user_pages(dev, data_ptr, false, + &num_pages, &user_pages); + if (ret) goto out; - } ret = i915_gem_object_set_to_cpu_domain(obj, 1); if (ret) @@ -940,7 +958,7 @@ i915_gem_shmem_pwrite_slow(struct drm_device *dev, } out: - for (i = 0; i < pinned_pages; i++) + for (i = 0; i < num_pages; i++) page_cache_release(user_pages[i]); drm_free_large(user_pages); -- 1.7.4.1 _______________________________________________ Intel-gfx mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/intel-gfx
